Commit Graph

390 Commits

Author SHA1 Message Date
Ingo Molnar
4d39c89f0b perf tools: Fix various typos in comments
Fix ~124 single-word typos and a few spelling errors in the perf tooling code,
accumulated over the years.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210321113734.GA248990@gmail.com
Link: http://lore.kernel.org/lkml/20210323160915.GA61903@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-03-23 17:13:43 -03:00
Arnaldo Carvalho de Melo
c1bd8a2b9f Merge branch 'perf/urgent' into perf/core
To get some fixes that didn't made into 5.11.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-02-16 11:52:16 -03:00
Jianlin Lv
105f75ebf9 perf probe: Fix kretprobe issue caused by GCC bug
Perf failed to add a kretprobe event with debuginfo of vmlinux which is
compiled by gcc with -fpatchable-function-entry option enabled.  The
same issue with kernel module.

Issue:

  # perf probe  -v 'kernel_clone%return $retval'
  ......
  Writing event: r:probe/kernel_clone__return _text+599624 $retval
  Failed to write event: Invalid argument
    Error: Failed to add events. Reason: Invalid argument (Code: -22)

  # cat /sys/kernel/debug/tracing/error_log
  [156.75] trace_kprobe: error: Retprobe address must be an function entry
  Command: r:probe/kernel_clone__return _text+599624 $retval
                                        ^

  # llvm-dwarfdump  vmlinux |grep  -A 10  -w 0x00df2c2b
  0x00df2c2b:   DW_TAG_subprogram
                DW_AT_external  (true)
                DW_AT_name      ("kernel_clone")
                DW_AT_decl_file ("/home/code/linux-next/kernel/fork.c")
                DW_AT_decl_line (2423)
                DW_AT_decl_column       (0x07)
                DW_AT_prototyped        (true)
                DW_AT_type      (0x00dcd492 "pid_t")
                DW_AT_low_pc    (0xffff800010092648)
                DW_AT_high_pc   (0xffff800010092b9c)
                DW_AT_frame_base        (DW_OP_call_frame_cfa)

  # cat /proc/kallsyms |grep kernel_clone
  ffff800010092640 T kernel_clone
  # readelf -s vmlinux |grep -i kernel_clone
  183173: ffff800010092640  1372 FUNC    GLOBAL DEFAULT    2 kernel_clone

  # objdump -d vmlinux |grep -A 10  -w \<kernel_clone\>:
  ffff800010092640 <kernel_clone>:
  ffff800010092640:       d503201f        nop
  ffff800010092644:       d503201f        nop
  ffff800010092648:       d503233f        paciasp
  ffff80001009264c:       a9b87bfd        stp     x29, x30, [sp, #-128]!
  ffff800010092650:       910003fd        mov     x29, sp
  ffff800010092654:       a90153f3        stp     x19, x20, [sp, #16]

The entry address of kernel_clone converted by debuginfo is _text+599624
(0x92648), which is consistent with the value of DW_AT_low_pc attribute.
But the symbolic address of kernel_clone from /proc/kallsyms is
ffff800010092640.

This issue is found on arm64, -fpatchable-function-entry=2 is enabled when
CONFIG_DYNAMIC_FTRACE_WITH_REGS=y;
Just as objdump displayed the assembler contents of kernel_clone,
GCC generate 2 NOPs  at the beginning of each function.

kprobe_on_func_entry detects that (_text+599624) is not the entry address
of the function, which leads to the failure of adding kretprobe event.

  kprobe_on_func_entry
  ->_kprobe_addr
  ->kallsyms_lookup_size_offset
  ->arch_kprobe_on_func_entry		// FALSE

The cause of the issue is that the first instruction in the compile unit
indicated by DW_AT_low_pc does not include NOPs.
This issue exists in all gcc versions that support
-fpatchable-function-entry option.

I have reported it to the GCC community:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98776

Currently arm64 and PA-RISC may enable fpatchable-function-entry option.
The kernel compiled with clang does not have this issue.

FIX:

This GCC issue only cause the registration failure of the kretprobe event
which doesn't need debuginfo. So, stop using debuginfo for retprobe.
map will be used to query the probe function address.

Signed-off-by: Jianlin Lv <Jianlin.Lv@arm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: clang-built-linux@googlegroups.com
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20210210062646.2377995-1-Jianlin.Lv@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-02-12 18:34:25 -03:00
Jin Yao
94253393df perf intlist: Change 'struct intlist' int member to 'unsigned long'
This is to let intlist support addresses as its payload.

One potential problem is it can't support negative number. But so far,
there is no such kind of use case.

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210207080935.31784-1-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-02-08 17:02:00 -03:00
Jiri Olsa
bf5411695a perf tools: Pass build_id object to build_id__sprintf()
Passing build_id object to build_id__sprintf function, so it can operate
with the proper size of build id.

This will create proper md5 build id readable names,
like following:

  a50e350e97c43b4708d09bcd85ebfff7

instead of:

  a50e350e97c43b4708d09bcd85ebfff700000000

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20201013192441.1299447-5-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-10-14 08:46:22 -03:00
Jiri Olsa
0aba7f036a perf tools: Use build_id object in dso
Replace build_id byte array with struct build_id object and all the code
that references it.

The objective is to carry size together with build id array, so it's
better to keep both together.

This is preparatory change for following patches, and there's no
functional change.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20201013192441.1299447-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-10-14 08:44:47 -03:00
Masami Hiramatsu
7cd5738d0d perf probe: Fall back to debuginfod query if debuginfo and source not found locally
Since 'perf probe' heavily depends on debuginfo, debuginfod gives us
many benefits on the 'perf probe' command on remote machine.

Especially, this will be helpful for the embedded devices which will not
have enough storage, or boot with a cross-build kernel whose source code
is in the host machine.

This will work as similar to commit c7a14fdcb3 ("perf build-ids:
Fall back to debuginfod query if debuginfo not found")

Tested with:

  (host) $ cd PATH/TO/KBUILD/DIR/
  (host) $ debuginfod -F .
  ...

  (remote) # perf probe -L vfs_read
  Failed to find the path for the kernel: No such file or directory
    Error: Failed to show lines.

  (remote) # export DEBUGINFOD_URLS="http://$HOST_IP:8002/"
  (remote) # perf probe -L vfs_read
  <vfs_read@...>
        0  ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos)
           {
        2         ssize_t ret;

                  if (!(file->f_mode & FMODE_READ))
                          return -EBADF;
        6         if (!(file->f_mode & FMODE_CAN_READ))
                          return -EINVAL;
        8         if (unlikely(!access_ok(buf, count)))
                          return -EFAULT;

       11         ret = rw_verify_area(READ, file, pos, count);
       12         if (ret)
                          return ret;
                  if (count > MAX_RW_COUNT)
  ...

  (remote) # perf probe -a "vfs_read count"
  Added new event:
    probe:vfs_read       (on vfs_read with count)

  (remote) # perf probe -l
    probe:vfs_read       (on vfs_read@ksrc/linux/fs/read_write.c with count)

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Frank Ch. Eigler <fche@redhat.com>
Cc: Aaron Merey <amerey@redhat.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Link: http://lore.kernel.org/lkml/160041610083.912668.13659563860278615846.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-09-18 09:20:47 -03:00
Masami Hiramatsu
ac7a75d1fb perf probe: Fix to adjust symbol address with correct reloc_sym address
'perf probe' uses ref_reloc_sym to adjust symbol offset address from
debuginfo address or ref_reloc_sym based address, but that is misusing
reloc_sym->addr and reloc_sym->unrelocated_addr.  If map is not
relocated (map->reloc == 0), we can use reloc_sym->addr as unrelocated
address instead of reloc_sym->unrelocated_addr.

This usually does not happen. If we have a non-stripped ELF binary, we
will use it for map and debuginfo, if not, we use only kallsyms without
debuginfo. Thus, the map is always relocated (ELF and DWARF binary) or
not relocated (kallsyms).

However, if we allow the combination of debuginfo and kallsyms based map
(like using debuginfod), we have to check the map->reloc and choose the
collect address of reloc_sym.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Frank Ch. Eigler <fche@redhat.com>
Cc: Aaron Merey <amerey@redhat.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Link: http://lore.kernel.org/lkml/160041609047.912668.14314639291419159274.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-09-18 09:19:03 -03:00
Masami Hiramatsu
3de2bf9dfb perf probe: Warn if the target function is a GNU indirect function
Warn if the probe target function is a GNU indirect function (GNU_IFUNC)
because it may not be what the user wants to probe.

The GNU indirect function ( https://sourceware.org/glibc/wiki/GNU_IFUNC )
is the dynamic symbol solved at runtime. An IFUNC function is a selector
which is invoked from the ELF loader, but the symbol address of the
function which will be modified by the IFUNC is the same as the IFUNC in
the symbol table. This can confuse users trying to probe such functions.

For example, memcpy is an IFUNC.

  probe_libc:memcpy    (on __new_memcpy_ifunc@x86_64/multiarch/memcpy.c in /usr/lib64/libc-2.30.so)

the probe is put on an IFUNC.

  perf  1742 [000] 26201.715632: probe_libc:memcpy: (7fdaa53824c0)
              7fdaa53824c0 __new_memcpy_ifunc+0x0 (inlined)
              7fdaa5d4a980 elf_machine_rela+0x6c0 (inlined)
              7fdaa5d4a980 elf_dynamic_do_Rela+0x6c0 (inlined)
              7fdaa5d4a980 _dl_relocate_object+0x6c0 (/usr/lib64/ld-2.30.so)
              7fdaa5d42155 dl_main+0x1cc5 (/usr/lib64/ld-2.30.so)
              7fdaa5d5831a _dl_sysdep_start+0x54a (/usr/lib64/ld-2.30.so)
              7fdaa5d3ffeb _dl_start_final+0x25b (inlined)
              7fdaa5d3ffeb _dl_start+0x25b (/usr/lib64/ld-2.30.so)
              7fdaa5d3f117 .annobin_rtld.c+0x7 (inlined)

And the event is invoked from the ELF loader instead of the target
program's main code.

Moreover, at this moment, we can not probe on the function which will
be selected by the IFUNC, because it is determined at runtime. But
uprobe will be prepared before running the target binary.

Thus, I decided to warn user when 'perf probe' detects that the probe
point is on an GNU IFUNC symbol. Someone who wants to probe an IFUNC
symbol to debug the IFUNC function can ignore this warning.

Committer notes:

I.e., this warning will be emitted if the probe point is an IFUNC:

  "Warning: The probe function (%s) is a GNU indirect function.\n"
  "Consider identifying the final function used at run time and set the probe directly on that.\n"

Complete set of steps:

  # readelf -sW /lib64/libc-2.29.so  | grep IFUNC | tail
   22196: 0000000000109a80   183 IFUNC   GLOBAL DEFAULT   14 __memcpy_chk
   22214: 00000000000b7d90   191 IFUNC   GLOBAL DEFAULT   14 __gettimeofday
   22336: 000000000008b690    60 IFUNC   GLOBAL DEFAULT   14 memchr
   22350: 000000000008b9b0    89 IFUNC   GLOBAL DEFAULT   14 __stpcpy
   22420: 000000000008bb10    76 IFUNC   GLOBAL DEFAULT   14 __strcasecmp_l
   22582: 000000000008a970    60 IFUNC   GLOBAL DEFAULT   14 strlen
   22585: 00000000000a54d0    92 IFUNC   WEAK   DEFAULT   14 wmemset
   22600: 000000000010b030    92 IFUNC   GLOBAL DEFAULT   14 __wmemset_chk
   22618: 000000000008b8a0   183 IFUNC   GLOBAL DEFAULT   14 __mempcpy
   22675: 000000000008ba70    76 IFUNC   WEAK   DEFAULT   14 strcasecmp
  #
  # perf probe -x /lib64/libc-2.29.so strlen
  Warning: The probe function (strlen) is a GNU indirect function.
  Consider identifying the final function used at run time and set the probe directly on that.
  Added new event:
    probe_libc:strlen    (on strlen in /usr/lib64/libc-2.29.so)

  You can now use it in all perf tools, such as:

  	perf record -e probe_libc:strlen -aR sleep 1

  #

Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lore.kernel.org/lkml/159438669349.62703.5978345670436126948.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-07-17 09:09:47 -03:00
Masami Hiramatsu
26bbf45fc8 perf probe: Avoid setting probes on the same address for the same event
There is a case that several same-name symbols points to the same
address.  In that case, 'perf probe' returns an error.

E.g.

  # perf probe -x /lib64/libc-2.30.so -v -a "memcpy arg1=%di"
  probe-definition(0): memcpy arg1=%di
  symbol:memcpy file:(null) line:0 offset:0 return:0 lazy:(null)
  parsing arg: arg1=%di into name:arg1 %di
  1 arguments
  symbol:setjmp file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:longjmp file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:longjmp_target file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:lll_lock_wait_private file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_arena_max file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_arena_test file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_tunable_tcache_max_bytes file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_tunable_tcache_count file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_tunable_tcache_unsorted_limit file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_trim_threshold file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_top_pad file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_mmap_threshold file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_mmap_max file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_perturb file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_mxfast file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_heap_new file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_arena_reuse_free_list file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_arena_reuse file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_arena_reuse_wait file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_arena_new file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_arena_retry file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_sbrk_less file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_heap_free file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_heap_less file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_tcache_double_free file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_heap_more file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_sbrk_more file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_malloc_retry file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_memalign_retry file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_free_dyn_thresholds file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_realloc_retry file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_calloc_retry file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt file:(null) line:0 offset:0 return:0 lazy:(null)
  Open Debuginfo file: /usr/lib/debug/usr/lib64/libc-2.30.so.debug
  Try to find probe point from debuginfo.
  Opening /sys/kernel/debug/tracing//README write=0
  Failed to find the location of the '%di' variable at this address.
   Perhaps it has been optimized out.
   Use -V with the --range option to show '%di' location range.
  An error occurred in debuginfo analysis (-2).
  Trying to use symbols.
  Opening /sys/kernel/debug/tracing//uprobe_events write=1
  Writing event: p:probe_libc/memcpy /usr/lib64/libc-2.30.so:0x914c0 arg1=%di
  Writing event: p:probe_libc/memcpy /usr/lib64/libc-2.30.so:0x914c0 arg1=%di
  Failed to write event: File exists
    Error: Failed to add events. Reason: File exists (Code: -17)

You can see that perf tried to write completely the same probe
definition twice, which caused an error.

To fix this issue, check the symbol list and drop duplicated symbols
(which has the same symbol name and address) from it.

With this patch:

  # perf probe -x /lib64/libc-2.30.so -a "memcpy arg1=%di"
  Failed to find the location of the '%di' variable at this address.
   Perhaps it has been optimized out.
   Use -V with the --range option to show '%di' location range.
  Added new events:
    probe_libc:memcpy    (on memcpy in /usr/lib64/libc-2.30.so with arg1=%di)
    probe_libc:memcpy    (on memcpy in /usr/lib64/libc-2.30.so with arg1=%di)

  You can now use it in all perf tools, such as:

  	perf record -e probe_libc:memcpy -aR sleep 1

Committer notes:

Fix this build error on 32-bit arches by using PRIx64 for symbol->start,
that is an u64:

  In file included from util/probe-event.c:27:
  util/probe-event.c: In function 'find_probe_trace_events_from_map':
  util/probe-event.c:2978:14: error: format '%lx' expects argument of type 'long unsigned int', but argument 5 has type 'u64' {aka 'long long unsigned int'} [-Werror=format=]
       pr_debug("Found duplicated symbol %s @ %lx\n",
                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  util/debug.h:17:21: note: in definition of macro 'pr_fmt'
   #define pr_fmt(fmt) fmt
                       ^~~
  util/probe-event.c:2978:5: note: in expansion of macro 'pr_debug'
       pr_debug("Found duplicated symbol %s @ %lx\n",
       ^~~~~~~~

Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Link: http://lore.kernel.org/lkml/159438666401.62703.15196394835032087840.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-07-17 09:07:34 -03:00
Sumanth Korikkar
9256c3031e perf probe: Fix user attribute access in kprobes
Issue:

  # perf probe -a 'do_sched_setscheduler pid policy param->sched_priority@user'

did not work before.

Fix:

Make:

  # perf probe -a 'do_sched_setscheduler pid policy param->sched_priority@user'

output equivalent to ftrace:

  # echo 'p:probe/do_sched_setscheduler _text+517384 pid=%r2:s32 policy=%r3:s32 sched_priority=+u0(%r4):s32' > /sys/kernel/debug/tracing/kprobe_events

Other:

1. Right now, __match_glob() does not handle [u]<offset>. For now, use
  *u]<offset>.

2. @user attribute was introduced in commit 1e032f7cfa ("perf-probe:
   Add user memory access attribute support")

Test:
1. perf probe -a 'do_sched_setscheduler  pid policy
   param->sched_priority@user'

2 ./perf script
   sched 305669 [000] 1614458.838675: perf_bpf_probe:func: (2904e508)
   pid=261614 policy=2 sched_priority=1

3. cat /sys/kernel/debug/tracing/trace
   <...>-309956 [006] .... 1616098.093957: 0: prio: 1

Committer testing:

Before:

  # perf probe -a 'do_sched_setscheduler pid policy param->sched_priority@user'
  param(type:sched_param) has no member sched_priority@user.
    Error: Failed to add events.
  # pahole sched_param
  struct sched_param {
  	int                        sched_priority;       /*     0     4 */

  	/* size: 4, cachelines: 1, members: 1 */
  	/* last cacheline: 4 bytes */
  };
  #

After:

  # perf probe -a 'do_sched_setscheduler pid policy param->sched_priority@user'
  Added new event:
    probe:do_sched_setscheduler (on do_sched_setscheduler with pid policy sched_priority=param->sched_priority)

  You can now use it in all perf tools, such as:

  	perf record -e probe:do_sched_setscheduler -aR sleep 1

  # cat /sys/kernel/debug/tracing/kprobe_events
  p:probe/do_sched_setscheduler _text+1113792 pid=%di:s32 policy=%si:s32 sched_priority=+u0(%dx):s32
  #

Fixes: 1e032f7cfa ("perf-probe: Add user memory access attribute support")
Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Reviewed-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: bpf@vger.kernel.org
LPU-Reference: 20200609081019.60234-2-sumanthk@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-06-09 12:40:04 -03:00
Masami Hiramatsu
2ae5d0d7d8 perf probe: Check address correctness by map instead of _etext
Since commit 03db8b583d ("perf tools: Fix
maps__find_symbol_by_name()") introduced map address range check in
maps__find_symbol_by_name(), we can not get "_etext" from kernel map
because _etext is placed on the edge of the kernel .text section (=
kernel map in perf.)

To fix this issue, this checks the address correctness by map address
range information (map->start and map->end) instead of using _etext
address.

This can cause an error if the target inlined function is embedded in
both __init function and normal function.

For exaample, request_resource() is a normal function but also embedded
in __init reserve_setup(). In this case, the probe point in
reserve_setup() must be skipped.

However, without this fix, it failes to setup all probe points:

  # ./perf probe -v request_resource
  probe-definition(0): request_resource
  symbol:request_resource file:(null) line:0 offset:0 return:0 lazy:(null)
  0 arguments
  Looking at the vmlinux_path (8 entries long)
  Using /usr/lib/debug/lib/modules/5.5.17-200.fc31.x86_64/vmlinux for symbols
  Open Debuginfo file: /usr/lib/debug/lib/modules/5.5.17-200.fc31.x86_64/vmlinux
  Try to find probe point from debuginfo.
  Matched function: request_resource [15e29ad]
  found inline addr: 0xffffffff82fbf892
  Probe point found: reserve_setup+204
  found inline addr: 0xffffffff810e9790
  Probe point found: request_resource+0
  Found 2 probe_trace_events.
  Opening /sys/kernel/debug/tracing//kprobe_events write=1
  Opening /sys/kernel/debug/tracing//README write=0
  Writing event: p:probe/request_resource _text+33290386
  Failed to write event: Invalid argument
    Error: Failed to add events. Reason: Invalid argument (Code: -22)
  #

With this fix,

  # ./perf probe request_resource
  reserve_setup is out of .text, skip it.
  Added new events:
    (null):(null)        (on request_resource)
    probe:request_resource (on request_resource)

  You can now use it in all perf tools, such as:

  	perf record -e probe:request_resource -aR sleep 1

  #

Fixes: 03db8b583d ("perf tools: Fix maps__find_symbol_by_name()")
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/158763967332.30755.4922496724365529088.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-05-28 10:03:24 -03:00
Masami Hiramatsu
80526491c2 perf probe: Fix to check blacklist address correctly
Fix to check kprobe blacklist address correctly with relocated address
by adjusting debuginfo address.

Since the address in the debuginfo is same as objdump, it is different
from relocated kernel address with KASLR.  Thus, 'perf probe' always
misses to catch the blacklisted addresses.

Without this patch, 'perf probe' can not detect the blacklist addresses
on a KASLR enabled kernel.

  # perf probe kprobe_dispatcher
  Failed to write event: Invalid argument
    Error: Failed to add events.
  #

With this patch, it correctly shows the error message.

  # perf probe kprobe_dispatcher
  kprobe_dispatcher is blacklisted function, skip it.
  Probe point 'kprobe_dispatcher' not found.
    Error: Failed to add events.
  #

Fixes: 9aaf5a5f47 ("perf probe: Check kprobes blacklist when adding new events")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/158763966411.30755.5882376357738273695.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-05-28 10:03:24 -03:00
Masami Hiramatsu
c6aab66a72 perf probe: Accept the instance number of kretprobe event
Since the commit 6a13a0d7b4 ("ftrace/kprobe: Show the maxactive number
on kprobe_events") introduced to show the instance number of kretprobe
events, the length of the 1st format of the kprobe event will not 1, but
it can be longer.  This caused a parser error in perf-probe.

Skip the length check the 1st format of the kprobe event to accept this
instance number.

Without this fix:

  # perf probe -a vfs_read%return
  Added new event:
    probe:vfs_read__return (on vfs_read%return)

  You can now use it in all perf tools, such as:

  	perf record -e probe:vfs_read__return -aR sleep 1

  # perf probe -l
  Semantic error :Failed to parse event name: r16:probe/vfs_read__return
    Error: Failed to show event list.

And with this fixes:

  # perf probe -a vfs_read%return
  ...
  # perf probe -l
    probe:vfs_read__return (on vfs_read%return)

Fixes: 6a13a0d7b4 ("ftrace/kprobe: Show the maxactive number on kprobe_events")
Reported-by: Yuxuan Shui <yshuiv7@gmail.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Yuxuan Shui <yshuiv7@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=207587
Link: http://lore.kernel.org/lkml/158877535215.26469.1113127926699134067.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-05-28 10:03:24 -03:00
Arnaldo Carvalho de Melo
c54d241b35 perf maps: Rename map_groups.h to maps.h
One more step in the merge of 'struct maps' with 'struct map_groups'.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-9ibtn3vua76f934t7woyf26w@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-11-26 11:07:46 -03:00
Arnaldo Carvalho de Melo
79b6bb73f8 perf maps: Merge 'struct maps' with 'struct map_groups'
And pick the shortest name: 'struct maps'.

The split existed because we used to have two groups of maps, one for
functions and one for variables, but that only complicated things,
sometimes we needed to figure out what was at some address and then had
to first try it on the functions group and if that failed, fall back to
the variables one.

That split is long gone, so for quite a while we had only one struct
maps per struct map_groups, simplify things by combining those structs.

First patch is the minimum needed to merge both, follow up patches will
rename 'thread->mg' to 'thread->maps', etc.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-hom6639ro7020o708trhxh59@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-11-26 11:07:46 -03:00
Masami Hiramatsu
cb40273085 perf probe: Trace a magic number if variable is not found
Trace a magic number as immediate value if the target variable is not
found at some probe points which is based on one probe event.

This feature is good for the case if you trace a source code line with
some local variables, which is compiled into several instructions and
some of the variables are optimized out on some instructions.

Even if so, with this feature, perf probe trace a magic number instead
of such disappeared variables and fold those probes on one event.

E.g. without this patch:

  # perf probe -D "pud_page_vaddr pud"
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  p:probe/pud_page_vaddr _text+23480787 pud=%ax:x64
  p:probe/pud_page_vaddr _text+23808453 pud=%bp:x64
  p:probe/pud_page_vaddr _text+23558082 pud=%ax:x64
  p:probe/pud_page_vaddr _text+328373 pud=%r8:x64
  p:probe/pud_page_vaddr _text+348448 pud=%bx:x64
  p:probe/pud_page_vaddr _text+23816818 pud=%bx:x64

With this patch:

  # perf probe -D "pud_page_vaddr pud" | head
  spurious_kernel_fault is blacklisted function, skip it.
  vmalloc_fault is blacklisted function, skip it.
  p:probe/pud_page_vaddr _text+23480787 pud=%ax:x64
  p:probe/pud_page_vaddr _text+149051 pud=\deade12d:x64
  p:probe/pud_page_vaddr _text+23808453 pud=%bp:x64
  p:probe/pud_page_vaddr _text+315926 pud=\deade12d:x64
  p:probe/pud_page_vaddr _text+23807209 pud=\deade12d:x64
  p:probe/pud_page_vaddr _text+23557365 pud=%ax:x64
  p:probe/pud_page_vaddr _text+314097 pud=%di:x64
  p:probe/pud_page_vaddr _text+314015 pud=\deade12d:x64
  p:probe/pud_page_vaddr _text+313893 pud=\deade12d:x64
  p:probe/pud_page_vaddr _text+324083 pud=\deade12d:x64

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Link: http://lore.kernel.org/lkml/157406476931.24476.6261475888681844285.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-11-18 19:09:23 -03:00
Masami Hiramatsu
72363540c0 perf probe: Support multiprobe event
Support multiprobe event if the event is based on function and lines and
kernel supports it. In this case, perf probe creates the first probe
with an event, and tries to append following probes on that event, since
those probes must be on the same source code line.

Before this patch;

  # perf probe -a vfs_read:18
  Added new events:
    probe:vfs_read_L18   (on vfs_read:18)
    probe:vfs_read_L18_1 (on vfs_read:18)

  You can now use it in all perf tools, such as:

  	perf record -e probe:vfs_read_L18_1 -aR sleep 1

  #

After this patch (on multiprobe supported kernel)
  # perf probe -a vfs_read:18
  Added new events:
    probe:vfs_read_L18   (on vfs_read:18)
    probe:vfs_read_L18   (on vfs_read:18)

  You can now use it in all perf tools, such as:

  	perf record -e probe:vfs_read_L18 -aR sleep 1

  #

Committer testing:

On a kernel that doesn't support multiprobe events, after this patch:

  # uname -a
  Linux quaco 5.3.8-200.fc30.x86_64 #1 SMP Tue Oct 29 14:46:22 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
  # grep append /sys/kernel/debug/tracing/README
  	    be modified by appending '.descending' or '.ascending' to a
  	    can be modified by appending any of the following modifiers
  #
  # perf probe -a vfs_read:18
  Added new events:
    probe:vfs_read_L18   (on vfs_read:18)
    probe:vfs_read_L18_1 (on vfs_read:18)

  You can now use it in all perf tools, such as:

  	perf record -e probe:vfs_read_L18_1 -aR sleep 1

  # perf probe -l
    probe:vfs_read_L18   (on vfs_read:18@fs/read_write.c)
    probe:vfs_read_L18_1 (on vfs_read:18@fs/read_write.c)
  #

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Link: http://lore.kernel.org/lkml/157406475010.24476.586290752591512351.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-11-18 19:03:38 -03:00
Masami Hiramatsu
15354d5469 perf probe: Generate event name with line number
Generate event name from function name with line number as
<function>_L<line_number>. Note that this is only for the new event
which is defined by the line number of function (except for line 0).

If there is another event on same line, you have to use
"-f" option. In that case, the new event has "_1" suffix.

 e.g.
  # perf probe -a kernel_read:2
  Added new event:
    probe:kernel_read_L2 (on kernel_read:2)

  You can now use it in all perf tools, such as:

  	perf record -e probe:kernel_read_L2 -aR sleep 1

But if we omit the line number or 0th line, it will
have no suffix.

  # perf probe -a kernel_read:0
  Added new event:
    probe:kernel_read (on kernel_read)

  You can now use it in all perf tools, such as:

  	perf record -e probe:kernel_read -aR sleep 1

  probe:kernel_read    (on kernel_read@linux-5.0.0/fs/read_write.c)
  probe:kernel_read_L2 (on kernel_read:2@linux-5.0.0/fs/read_write.c)

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Link: http://lore.kernel.org/lkml/157406474026.24476.2828897745502059569.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-11-18 19:02:00 -03:00
Arnaldo Carvalho de Melo
8efc4f0568 perf maps: Add for_each_entry()/_safe() iterators
To reduce boilerplate, provide a more compact form using an idiom
present in other trees of data structures.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-59gmq4kg1r68ou1wknyjl78x@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-11-06 15:49:25 -03:00
Masami Hiramatsu
9e6124d9d6 perf probe: Fix to clear tev->nargs in clear_probe_trace_event()
Since add_probe_trace_event() can reuse tf->tevs[i] after calling
clear_probe_trace_event(), this can make perf-probe crash if the 1st
attempt of probe event finding fails to find an event argument, and the
2nd attempt fails to find probe point.

E.g.
  $ perf probe -D "task_pid_nr tsk"
  Failed to find 'tsk' in this function.
  Failed to get entry address of warn_bad_vsyscall
  Segmentation fault (core dumped)

Committer testing:

After the patch:

  $ perf probe -D "task_pid_nr tsk"
  Failed to find 'tsk' in this function.
  Failed to get entry address of warn_bad_vsyscall
  Failed to get entry address of signal_fault
  Failed to get entry address of show_signal
  Failed to get entry address of umip_printk
  Failed to get entry address of __bad_area_nosemaphore
  <SNIP>
  Failed to get entry address of sock_set_timeout
  Failed to get entry address of tcp_recvmsg
  Probe point 'task_pid_nr' not found.
    Error: Failed to add events.
  $

Fixes: 092b1f0b5f ("perf probe: Clear probe_trace_event when add_probe_trace_event() fails")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lore.kernel.org/lkml/156856587999.25775.5145779959474477595.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-09-20 15:30:09 -03:00
Arnaldo Carvalho de Melo
fa0d98462f perf tools: Remove needless evlist.h include directives
Remove the last unneeded use of cache.h in a header, we can check where
it is really needed, i.e. we can remove it and be sure that it isn't
being obtained indirectly.

This is an old file, used by now incorrectly in many places, so it was
providing includes needed indirectly, fixup this fallout.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-3x3l8gihoaeh7714os861ia7@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-08-31 22:24:10 -03:00
Arnaldo Carvalho de Melo
4becb2395f perf tools: Remove needless thread.h include directives
Now that thread.h isn't included by any other header, we can check where
it is really needed, i.e. we can remove it and be sure that it isn't
being obtained indirectly.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-kh333ivjbw05wsggckpziu86@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-08-31 22:24:10 -03:00
Arnaldo Carvalho de Melo
4a3cec8494 perf dsos: Move the dsos struct and its methods to separate source files
So that we can reduce the header dependency tree further, in the process
noticed that lots of places were getting even things like build-id
routines and 'struct perf_tool' definition indirectly, so fix all those
too.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-ti0btma9ow5ndrytyoqdk62j@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-08-31 22:24:10 -03:00
Ingo Molnar
49902052fc perf/urgent fixes:
perf.data:
 
   Alexey Budankov:
 
   - Fix loading of compressed data split across adjacent records
 
   Jiri Olsa:
 
   - Fix buffer size setting for processing CPU topology perf.data header.
 
 perf stat:
 
   Jiri Olsa:
 
   - Fix segfault for event group in repeat mode
 
   Cong Wang:
 
   - Always separate "stalled cycles per insn" line, it was being appended to
     the "instructions" line.
 
 perf script:
 
   Andi Kleen:
 
   - Fix --max-blocks man page description.
 
   - Improve man page description of metrics.
 
   - Fix off by one in brstackinsn IPC computation.
 
 perf probe:
 
   Arnaldo Carvalho de Melo:
 
   - Avoid calling freeing routine multiple times for same pointer.
 
 perf build:
 
   - Do not use -Wshadow on gcc < 4.8, avoiding too strict warnings
     treated as errors, breaking the build.
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-urgent-for-mingo-5.3-20190723' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/urgent fixes from Arnaldo Carvalho de Melo:

perf.data:

  Alexey Budankov:

  - Fix loading of compressed data split across adjacent records

  Jiri Olsa:

  - Fix buffer size setting for processing CPU topology perf.data header.

perf stat:

  Jiri Olsa:

  - Fix segfault for event group in repeat mode

  Cong Wang:

  - Always separate "stalled cycles per insn" line, it was being appended to
    the "instructions" line.

perf script:

  Andi Kleen:

  - Fix --max-blocks man page description.

  - Improve man page description of metrics.

  - Fix off by one in brstackinsn IPC computation.

perf probe:

  Arnaldo Carvalho de Melo:

  - Avoid calling freeing routine multiple times for same pointer.

perf build:

  - Do not use -Wshadow on gcc < 4.8, avoiding too strict warnings
    treated as errors, breaking the build.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-23 23:41:33 +02:00
Arnaldo Carvalho de Melo
df8350ed56 perf probe: Set pev->nargs to zero after freeing pev->args entries
So that, when perf_add_probe_events() fails, like in:

  # perf probe icmp_rcv:64 "type=icmph->type"
  Failed to find 'icmph' in this function.
    Error: Failed to add events.
  Segmentation fault (core dumped)
  #

We don't segfault.

clear_perf_probe_event() was zeroing the whole pev, and since the switch
to zfree() for the members in the pev, that memset() was removed, which
left nargs with its original value, in the above case 1.

With the memset the same pev could be passed to clear_perf_probe_event()
multiple times, since all it would have would be zeroes, and free()
accepts zero, the loop would not happen and we would just memset it
again to zeroes.

Without it we got that segfault, so zero nargs to keep it like it was,
next cset will avoid calling clear_perf_probe_event() for the same pevs
in case of failure.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Fixes: d8f9da2404 ("perf tools: Use zfree() where applicable")
Link: https://lkml.kernel.org/n/tip-802f2jypnwqsvyavvivs8464@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-23 09:04:25 -03:00
Linus Torvalds
818e95c768 The main changes in this release include:
- Add user space specific memory reading for kprobes
  - Allow kprobes to be executed earlier in boot
 
 The rest are mostly just various clean ups and small fixes.
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Merge tag 'trace-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "The main changes in this release include:

   - Add user space specific memory reading for kprobes

   - Allow kprobes to be executed earlier in boot

  The rest are mostly just various clean ups and small fixes"

* tag 'trace-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (33 commits)
  tracing: Make trace_get_fields() global
  tracing: Let filter_assign_type() detect FILTER_PTR_STRING
  tracing: Pass type into tracing_generic_entry_update()
  ftrace/selftest: Test if set_event/ftrace_pid exists before writing
  ftrace/selftests: Return the skip code when tracing directory not configured in kernel
  tracing/kprobe: Check registered state using kprobe
  tracing/probe: Add trace_event_call accesses APIs
  tracing/probe: Add probe event name and group name accesses APIs
  tracing/probe: Add trace flag access APIs for trace_probe
  tracing/probe: Add trace_event_file access APIs for trace_probe
  tracing/probe: Add trace_event_call register API for trace_probe
  tracing/probe: Add trace_probe init and free functions
  tracing/uprobe: Set print format when parsing command
  tracing/kprobe: Set print format right after parsed command
  kprobes: Fix to init kprobes in subsys_initcall
  tracepoint: Use struct_size() in kmalloc()
  ring-buffer: Remove HAVE_64BIT_ALIGNED_ACCESS
  ftrace: Enable trampoline when rec count returns back to one
  tracing/kprobe: Do not run kprobe boot tests if kprobe_event is on cmdline
  tracing: Make a separate config for trace event self tests
  ...
2019-07-18 11:51:00 -07:00
Arnaldo Carvalho de Melo
e56fbc9dc7 perf tools: Use list_del_init() more thorougly
To allow for destructors to check if they're operating on a object still
in a list, and to avoid going from use after free list entries into
still valid, or even also other already removed from list entries.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-deh17ub44atyox3j90e6rksu@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-09 10:13:27 -03:00
Arnaldo Carvalho de Melo
d8f9da2404 perf tools: Use zfree() where applicable
In places where the equivalent was already being done, i.e.:

   free(a);
   a = NULL;

And in placs where struct members are being freed so that if we have
some erroneous reference to its struct, then accesses to freed members
will result in segfaults, which we can detect faster than use after free
to areas that may still have something seemingly valid.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-jatyoofo5boc1bsvoig6bb6i@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-09 10:13:27 -03:00
Arnaldo Carvalho de Melo
7f7c536f23 tools lib: Adopt zalloc()/zfree() from tools/perf
Eroding a bit more the tools/perf/util/util.h hodpodge header.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-natazosyn9rwjka25tvcnyi0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-09 10:13:26 -03:00
Arnaldo Carvalho de Melo
3052ba56bc tools perf: Move from sane_ctype.h obtained from git to the Linux's original
We got the sane_ctype.h headers from git and kept using it so far, but
since that code originally came from the kernel sources to the git
sources, perhaps its better to just use the one in the kernel, so that
we can leverage tools/perf/check_headers.sh to be notified when our copy
gets out of sync, i.e. when fixes or goodies are added to the code we've
copied.

This will help with things like tools/lib/string.c where we want to have
more things in common with the kernel, such as strim(), skip_spaces(),
etc so as to go on removing the things that we have in tools/perf/util/
and instead using the code in the kernel, indirectly and removing things
like EXPORT_SYMBOL(), etc, getting notified when fixes and improvements
are made to the original code.

Hopefully this also should help with reducing the difference of code
hosted in tools/ to the one in the kernel proper.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-7k9868l713wqtgo01xxygn12@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-06-25 21:02:47 -03:00
Thomas Gleixner
1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00
Masami Hiramatsu
1e032f7cfa perf-probe: Add user memory access attribute support
Add user memory access attribute for kprobe event arguments.
If a given 'local variable' is in user-space, User can
specify memory access method by '@user' suffix. This is
not only for string but also for data structure.

If we access a field of data structure in user memory from
kernel on some arch, it will fail. e.g.

 perf probe -a "sched_setscheduler param->sched_priority"

This will fail to access the "param->sched_priority" because
the param is __user pointer. Instead, we can now specify
@user suffix for such argument.

 perf probe -a "sched_setscheduler param->sched_priority@user"

Note that kernel memory access with "@user" must always fail
on any arch.

Link: http://lkml.kernel.org/r/155789874562.26965.10836126971405890891.stgit@devnote2

Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-05-25 23:04:42 -04:00
Adrian Hunter
eaeffeb983 perf probe: Fix getting the kernel map
Since commit 4d99e41365 ("perf machine: Workaround missing maps for
x86 PTI entry trampolines"), perf tools has been creating more than one
kernel map, however 'perf probe' assumed there could be only one.

Fix by using machine__kernel_map() to get the main kernel map.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiufei Xue <jiufei.xue@linux.alibaba.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Cc: Xu Yu <xuyu@linux.alibaba.com>
Fixes: 4d99e41365 ("perf machine: Workaround missing maps for x86 PTI entry trampolines")
Fixes: d83212d5dd ("kallsyms, x86: Export addresses of PTI entry trampolines")
Link: http://lkml.kernel.org/r/2ed432de-e904-85d2-5c36-5897ddc5b23b@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-03-11 11:56:03 -03:00
Arnaldo Carvalho de Melo
4d6101f5fd perf probe: Clarify error message about not finding kernel modules debuginfo
'perf probe' supports using just the kernel module name, but that will
work only when the module is loaded, or using the full pathname to the
file with the DWARF debug info, but the warning was cryptic:

Before:

  # perf probe -m cls_flower -L fl_change
  Failed to find the path for cls_flower: No such file or directory
    Error: Failed to show lines.
  #

After:

  # perf probe -m cls_flower -L fl_change
  Module cls_flower is not loaded, please specify its full path name.
    Error: Failed to show lines.
  # perf probe -m /lib/modules/5.0.0-rc7+/kernel/net/sched/cls_flower.ko -L fl_change | head -7
  <fl_change@/home/acme/git/linux/net/sched/cls_flower.c:0>
        0  static int fl_change(struct net *net, struct sk_buff *in_skb,
         		       struct tcf_proto *tp, unsigned long base,
         		       u32 handle, struct nlattr **tca,
         		       void **arg, bool ovr, struct netlink_ext_ack *extack)
        4  {
        5  	struct cls_fl_head *head = rtnl_dereference(tp->root);
  #

The behaviour doesn't change when the module is loaded:

  # modprobe cls_flower
  # perf probe -m cls_flower -L fl_change | head -7
  <fl_change@/home/acme/git/linux/net/sched/cls_flower.c:0>
        0  static int fl_change(struct net *net, struct sk_buff *in_skb,
                               struct tcf_proto *tp, unsigned long base,
                               u32 handle, struct nlattr **tca,
                               void **arg, bool ovr, struct netlink_ext_ack *extack)
        4  {
        5         struct cls_fl_head *head = rtnl_dereference(tp->root);
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Marcelo Ricardo Leitner <mleitner@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-q4njvk9mshra00jacqjbzfn5@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-02-28 14:20:35 -03:00
Arnaldo Carvalho de Melo
41f30914fc perf map: Move structs and prototypes for map groups to a separate header
And since machine.h only needs what is in there, make it stop including
map.h and instead include this newly introduced map_groups.h instead.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-dbob25fv5rp2rjpwlnterf38@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-02-06 10:00:38 -03:00
Arnaldo Carvalho de Melo
1101f69af5 pref tools: Add missing map.h includes
Lots of places get the map.h file indirectly, and since we're going to
remove it from machine.h, then those need to include it directly, do it
now, before we remove that dep.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-ob8jehdjda8h5jsrv9dqj9tf@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-02-06 10:00:38 -03:00
Davidlohr Bueso
7137ff50b6 perf symbols: Use cached rbtrees
At the cost of an extra pointer, we can avoid the O(logN) cost of
finding the first element in the tree (smallest node).

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20181206191819.30182-6-dave@stgolabs.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-01-25 15:12:10 +01:00
Arnaldo Carvalho de Melo
40f3b2d20b perf namespaces: Remove namespaces.h from .h headers
There we need just forward declarations, so remove it and add it just on
the .c files that actually touch the struct definitions.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-wsjxzt99p83jubt6hu0med0f@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-01-25 15:12:09 +01:00
Ingo Molnar
adba163441 perf tools: Fix diverse comment typos
Go over the tools/ files that are maintained in Arnaldo's tree and
fix common typos: half of them were in comments, the other half
in JSON files.

No change in functionality intended.

Committer notes:

This was split from a larger patch as there are code that is,
additionally, maintained outside the kernel tree, so to ease
cherry-picking and/or backporting, split this into multiple patches.

Just typos in comments, no need to backport, reducing the possibility of
possible backporting artifacts.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20181203102200.GA104797@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-12-17 14:56:47 -03:00
Ravi Bangoria
5a5e3d3cea perf probe: Support SDT markers having reference counter (semaphore)
With this, perf buildid-cache will save SDT markers with reference
counter in probe cache. Perf probe will be able to probe markers
having reference counter. Ex,

  # readelf -n /tmp/tick | grep -A1 loop2
    Name: loop2
    ... Semaphore: 0x0000000010020036

  # ./perf buildid-cache --add /tmp/tick
  # ./perf probe sdt_tick:loop2
  # ./perf stat -e sdt_tick:loop2 /tmp/tick
    hi: 0
    hi: 1
    hi: 2
    ^C
     Performance counter stats for '/tmp/tick':
                 3      sdt_tick:loop2
       2.561851452 seconds time elapsed

Link: http://lkml.kernel.org/r/20180820044250.11659-5-ravi.bangoria@linux.ibm.com

Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reviewed-by: Song Liu <songliubraving@fb.com>
Tested-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-09-24 04:44:54 -04:00
Arnaldo Carvalho de Melo
f622df5ed7 perf probe: Use return of map__get() to make code more compact
The __get() idiom returns a reference count for the object passed, i.e.
all functions of this type return the object passed, so take advantage
of that to make the code more compact.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-ds6vdm7clh070512rpydidsc@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-06-04 10:28:50 -03:00
Arnaldo Carvalho de Melo
107cad95ff perf machine: Ditch find_kernel_function variants
Since we do not have split symtabs anymore, no need to have explicit
find_kernel_function variants, use the find_kernel_symbol ones.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-hiw2ryflju000f6wl62128it@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-30 12:20:54 -03:00
Arnaldo Carvalho de Melo
3183f8ca30 perf symbols: Unify symbol maps
Remove the split of symbol tables for data (MAP__VARIABLE) and for
functions (MAP__FUNCTION), its unneeded and there were various places
doing two lookups to find a symbol, so simplify this.

We still will consider only the symbols that matched the filters in
place, i.e. see the (elf_(sec,sym)|symbol_type)__filter() routines in
the patch, just so that we consider only the same symbols as before,
to reduce the possibility of regressions.

All the tests on 50-something build environments, in varios versions
of lots of distros and cross build environments were performed without
build regressions, as usual with all pull requests the other tests were
also performed: 'perf test' and 'make -C tools/perf build-test'.

Also this was done at a great granularity so that regressions can be
bisected more easily.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-hiq0fy2rsleupnqqwuojo1ne@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-27 10:47:06 -03:00
Arnaldo Carvalho de Melo
68a741868a perf machine: Introduce machine__kernel_maps()
That returns the a data structure contained the ordered list of kernel
modules + the main kernel maps, one more step in removing the
MAP__{FUNCTION,VARIABLE} split.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-qsgbxfyaohc80c9ma049dubm@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-26 13:47:10 -03:00
Arnaldo Carvalho de Melo
83cf774b02 perf map: Shorten map_groups__find_by_name() signature
Another step in the road to elliminate the MAP_{FUNCTION,VARIABLE}
separation, reducing the exposure to these details in the tools using
the symbol APIs.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-8a1hvrqe3r5i0kw865u3uxwt@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-26 13:47:09 -03:00
Masami Hiramatsu
c588d15812 perf probe: Support escaped character in parser
Support the special characters escaped by '\' in parser.  This allows
user to specify versions directly like below.

  =====
  # ./perf probe -x /lib64/libc-2.25.so malloc_get_state\\@GLIBC_2.2.5
  Added new event:
    probe_libc:malloc_get_state (on malloc_get_state@GLIBC_2.2.5 in /usr/lib64/libc-2.25.so)

  You can now use it in all perf tools, such as:

	  perf record -e probe_libc:malloc_get_state -aR sleep 1

  =====

Or, you can use separators in source filename, e.g.

  =====
  # ./perf probe -x /opt/test/a.out foo+bar.c:3
  Semantic error :There is non-digit character in offset.
    Error: Command Parse Error.
  =====

Usually "+" in source file cause parser error, but

  =====
  # ./perf probe -x /opt/test/a.out foo\\+bar.c:4
  Added new event:
    probe_a:main         (on @foo+bar.c:4 in /opt/test/a.out)

  You can now use it in all perf tools, such as:

	  perf record -e probe_a:main -aR sleep 1
  =====

escaped "\+" allows you to specify that.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Acked-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: bhargavb <bhargavaramudu@gmail.com>
Cc: linux-rt-users@vger.kernel.org
Link: http://lkml.kernel.org/r/151309111236.18107.5634753157435343410.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-12-27 12:15:55 -03:00
Masami Hiramatsu
4b3a2716dd perf probe: Find versioned symbols from map
Commit d80406453a ("perf symbols: Allow user probes on versioned
symbols") allows user to find default versioned symbols (with "@@") in
map. However, it did not enable normal versioned symbol (with "@") for
perf-probe.  E.g.

  =====
  # ./perf probe -x /lib64/libc-2.25.so malloc_get_state
  Failed to find symbol malloc_get_state in /usr/lib64/libc-2.25.so
    Error: Failed to add events.
  =====

This solves above issue by improving perf-probe symbol search function,
as below.

  =====
  # ./perf probe -x /lib64/libc-2.25.so malloc_get_state
  Added new event:
    probe_libc:malloc_get_state (on malloc_get_state in /usr/lib64/libc-2.25.so)

  You can now use it in all perf tools, such as:

	  perf record -e probe_libc:malloc_get_state -aR sleep 1

  # ./perf probe -l
    probe_libc:malloc_get_state (on malloc_get_state@GLIBC_2.2.5 in /usr/lib64/libc-2.25.so)
  =====

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Acked-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: bhargavb <bhargavaramudu@gmail.com>
Cc: linux-rt-users@vger.kernel.org
Link: http://lkml.kernel.org/r/151275049269.24652.1639103455496216255.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-12-27 12:15:54 -03:00
Masami Hiramatsu
e63c625a1e perf probe: Add __return suffix for return events
Add __return suffix for function return events automatically. Without
this, user have to give --force option and will see the number suffix
for each event like "function_1", which is not easy to recognize.
Instead, this adds __return suffix to it automatically.  E.g.

  =====
  # ./perf probe -x /lib64/libc-2.25.so 'malloc*%return'
  Added new events:
    probe_libc:malloc_printerr__return (on malloc*%return in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_consolidate__return (on malloc*%return in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_check__return (on malloc*%return in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_hook_ini__return (on malloc*%return in /usr/lib64/libc-2.25.so)
    probe_libc:malloc__return (on malloc*%return in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_trim__return (on malloc*%return in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_usable_size__return (on malloc*%return in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_stats__return (on malloc*%return in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_info__return (on malloc*%return in /usr/lib64/libc-2.25.so)
    probe_libc:mallochook__return (on malloc*%return in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_get_state__return (on malloc*%return in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_set_state__return (on malloc*%return in /usr/lib64/libc-2.25.so)

  You can now use it in all perf tools, such as:

	  perf record -e probe_libc:malloc_set_state__return -aR sleep 1

  =====

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Reviewed-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: bhargavb <bhargavaramudu@gmail.com>
Cc: linux-rt-users@vger.kernel.org
Link: http://lkml.kernel.org/r/151275046418.24652.6696011972866498489.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-12-27 12:15:54 -03:00
Masami Hiramatsu
a3110cd9d0 perf probe: Cut off the version suffix from event name
Cut off the version suffix (e.g. @GLIBC_2.2.5 etc.) from automatic
generated event name. This fixes wildcard event adding like below case;

  =====
  # perf probe -x /lib64/libc-2.25.so malloc*
  Internal error: "malloc_get_state@GLIBC_2" is wrong event name.
    Error: Failed to add events.
  =====

This failure was caused by a versioned suffix symbol.

With this fix, perf probe automatically cuts the suffix after @ as
below.

  =====
  # ./perf probe -x /lib64/libc-2.25.so malloc*
  Added new events:
    probe_libc:malloc_printerr (on malloc* in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_consolidate (on malloc* in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_check (on malloc* in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_hook_ini (on malloc* in /usr/lib64/libc-2.25.so)
    probe_libc:malloc    (on malloc* in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_trim (on malloc* in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_usable_size (on malloc* in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_stats (on malloc* in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_info (on malloc* in /usr/lib64/libc-2.25.so)
    probe_libc:mallochook (on malloc* in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_get_state (on malloc* in /usr/lib64/libc-2.25.so)
    probe_libc:malloc_set_state (on malloc* in /usr/lib64/libc-2.25.so)

  You can now use it in all perf tools, such as:

	  perf record -e probe_libc:malloc_set_state -aR sleep 1

  =====

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Reported-by: bhargavb <bhargavaramudu@gmail.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Reviewed-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: linux-rt-users@vger.kernel.org
Link: http://lkml.kernel.org/r/None
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-12-27 12:15:53 -03:00
Masami Hiramatsu
9f5c6d8777 perf probe: Add warning message if there is unexpected event name
This improve the error message so that user can know event-name error
before writing new events to kprobe-events interface.

E.g.
   ======
   #./perf probe -x /lib64/libc-2.25.so malloc_get_state*
   Internal error: "malloc_get_state@GLIBC_2" is an invalid event name.
     Error: Failed to add events.
   ======

Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Reviewed-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: bhargavb <bhargavaramudu@gmail.com>
Cc: linux-rt-users@vger.kernel.org
Link: http://lkml.kernel.org/r/151275040665.24652.5188568529237584489.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-12-27 12:15:53 -03:00
Li Bin
2c29461e27 perf probe: Fix kprobe blacklist checking condition
The commit 9aaf5a5f47 ("perf probe: Check kprobes blacklist when
adding new events"), 'perf probe' supports checking the blacklist of the
fuctions which can not be probed.  But the checking condition is wrong,
that the end_addr of the symbol which is the start_addr of the next
symbol can't be included.

Committer notes:

IOW make it match its kernel counterpart in kernel/kprobes.c:

  bool within_kprobe_blacklist(unsigned long addr)

Each entry have as its end address not its end address, but the first
address _outside_ that symbol, which for related functions, is the first
address of the next symbol, like these from kernel/trace/trace_probe.c:

0xffffffffbd198df0-0xffffffffbd198e40	print_type_u8
0xffffffffbd198e40-0xffffffffbd198e90	print_type_u16
0xffffffffbd198e90-0xffffffffbd198ee0	print_type_u32
0xffffffffbd198ee0-0xffffffffbd198f30	print_type_u64
0xffffffffbd198f30-0xffffffffbd198f80	print_type_s8
0xffffffffbd198f80-0xffffffffbd198fd0	print_type_s16
0xffffffffbd198fd0-0xffffffffbd199020	print_type_s32
0xffffffffbd199020-0xffffffffbd199070	print_type_s64
0xffffffffbd199070-0xffffffffbd1990c0	print_type_x8
0xffffffffbd1990c0-0xffffffffbd199110	print_type_x16
0xffffffffbd199110-0xffffffffbd199160	print_type_x32
0xffffffffbd199160-0xffffffffbd1991b0	print_type_x64

But not always:

0xffffffffbd1997b0-0xffffffffbd1997c0	fetch_kernel_stack_address (kernel/trace/trace_probe.c)
0xffffffffbd1c57f0-0xffffffffbd1c58b0	__context_tracking_enter   (kernel/context_tracking.c)

Signed-off-by: Li Bin <huawei.libin@huawei.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: zhangmengting@huawei.com
Fixes: 9aaf5a5f47 ("perf probe: Check kprobes blacklist when adding new events")
Link: http://lkml.kernel.org/r/1504011443-7269-1-git-send-email-huawei.libin@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-08-29 11:14:12 -03:00
Krister Johansen
f045b8c4b3 perf buildid-cache: Support binary objects from other namespaces
Teach buildid-cache how to add, remove, and update binary objects from
other mount namespaces.  Allow probe events tracing binaries in
different namespaces to add their objects to the probe and build-id
caches too.  As a handy side effect, this also lets us access SDT probes
in binaries from alternate mount namespaces.

Signed-off-by: Krister Johansen <kjlx@templeofstupid.com>
Tested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1499305693-1599-5-git-send-email-kjlx@templeofstupid.com
[ Add util/namespaces.c to tools/perf/util/python-ext-sources, to fix the python binding 'perf test' ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-07-18 23:14:11 -03:00
Krister Johansen
544abd44c7 perf probe: Allow placing uprobes in alternate namespaces.
Teaches perf how to place a uprobe on a file that's in a different mount
namespace.  The user must add the probe using the --target-ns argument
to perf probe.  Once it has been placed, it may be recorded against
without further namespace-specific commands.

Signed-off-by: Krister Johansen <kjlx@templeofstupid.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
[ PPC build fixed by Ravi: ]
Link: http://lkml.kernel.org/r/1500287542-6219-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
[ Fix !HAVE_DWARF_SUPPORT build ]
Link: http://lkml.kernel.org/r/1499305693-1599-4-git-send-email-kjlx@templeofstupid.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-07-18 23:14:10 -03:00
Björn Töpel
7598f8bc13 perf probe: Fix probe definition for inlined functions
In commit 613f050d68 ("perf probe: Fix to probe on gcc generated
functions in modules"), the offset from symbol is, incorrectly, added
to the trace point address. This leads to incorrect probe trace points
for inlined functions and when using relative line number on symbols.

Prior this patch:
  $ perf probe -m nf_nat -D in_range
  p:probe/in_range nf_nat:in_range.isra.9+0
  $ perf probe -m i40e -D i40e_clean_rx_irq
  p:probe/i40e_clean_rx_irq i40e:i40e_napi_poll+2212
  $ perf probe -m i40e -D i40e_clean_rx_irq:16
  p:probe/i40e_clean_rx_irq i40e:i40e_lan_xmit_frame+626

After:
  $ perf probe -m nf_nat -D in_range
  p:probe/in_range nf_nat:in_range.isra.9+0
  $ perf probe -m i40e -D i40e_clean_rx_irq
  p:probe/i40e_clean_rx_irq i40e:i40e_napi_poll+1106
  $ perf probe -m i40e -D i40e_clean_rx_irq:16
  p:probe/i40e_clean_rx_irq i40e:i40e_napi_poll+2665

Committer testing:

Using 'pfunct', a tool found in the 'dwarves' package [1], one can ask what are
the functions that while not being explicitely marked as inline, were inlined
by the compiler:

  # pfunct --cc_inlined /lib/modules/4.12.0-rc4+/kernel/drivers/net/ethernet/intel/e1000e/e1000e.ko | head
  __ew32
  e1000_regdump
  e1000e_dump_ps_pages
  e1000_desc_unused
  e1000e_systim_to_hwtstamp
  e1000e_rx_hwtstamp
  e1000e_update_rdt_wa
  e1000e_update_tdt_wa
  e1000_put_txbuf
  e1000_consume_page

Then ask 'perf probe' to produce the kprobe_tracer probe definitions for two of
them:

  # perf probe -m e1000e -D e1000e_rx_hwtstamp
  p:probe/e1000e_rx_hwtstamp e1000e:e1000_receive_skb+74

  # perf probe -m e1000e -D e1000_consume_page
  p:probe/e1000_consume_page e1000e:e1000_clean_jumbo_rx_irq+876
  p:probe/e1000_consume_page_1 e1000e:e1000_clean_jumbo_rx_irq+1506
  p:probe/e1000_consume_page_2 e1000e:e1000_clean_rx_irq_ps+1074

Now lets concentrate on the 'e1000_consume_page' one, that was inlined twice in
e1000_clean_jumbo_rx_irq(), lets see what readelf says about the DWARF tags for
that function:

  $ readelf -wi /lib/modules/4.12.0-rc4+/kernel/drivers/net/ethernet/intel/e1000e/e1000e.ko
  <SNIP>
  <1><13e27b>: Abbrev Number: 121 (DW_TAG_subprogram)
    <13e27c>   DW_AT_name        : (indirect string, offset: 0xa8945): e1000_clean_jumbo_rx_irq
    <13e287>   DW_AT_low_pc      : 0x17a30
  <3><13e6ef>: Abbrev Number: 119 (DW_TAG_inlined_subroutine)
    <13e6f0>   DW_AT_abstract_origin: <0x13ed2c>
    <13e6f4>   DW_AT_low_pc      : 0x17be6
  <SNIP>
  <1><13ed2c>: Abbrev Number: 142 (DW_TAG_subprogram)
     <13ed2e>   DW_AT_name        : (indirect string, offset: 0xa54c3): e1000_consume_page

So, the first time in e1000_clean_jumbo_rx_irq() where e1000_consume_page() is
inlined is at PC 0x17be6, which subtracted from e1000_clean_jumbo_rx_irq()'s
address, gives us the offset we should use in the probe definition:

  0x17be6 - 0x17a30 = 438

but above we have 876, which is twice as much.

Lets see the second inline expansion of e1000_consume_page() in
e1000_clean_jumbo_rx_irq():

  <3><13e86e>: Abbrev Number: 119 (DW_TAG_inlined_subroutine)
    <13e86f>   DW_AT_abstract_origin: <0x13ed2c>
    <13e873>   DW_AT_low_pc      : 0x17d21

  0x17d21 - 0x17a30 = 753

So we where adding it at twice the offset from the containing function as we
should.

And then after this patch:

  # perf probe -m e1000e -D e1000e_rx_hwtstamp
  p:probe/e1000e_rx_hwtstamp e1000e:e1000_receive_skb+37

  # perf probe -m e1000e -D e1000_consume_page
  p:probe/e1000_consume_page e1000e:e1000_clean_jumbo_rx_irq+438
  p:probe/e1000_consume_page_1 e1000e:e1000_clean_jumbo_rx_irq+753
  p:probe/e1000_consume_page_2 e1000e:e1000_clean_jumbo_rx_irq+1353
  #

Which matches the two first expansions and shows that because we were
doubling the offset it would spill over the next function:

  readelf -sw /lib/modules/4.12.0-rc4+/kernel/drivers/net/ethernet/intel/e1000e/e1000e.ko
   673: 0000000000017a30  1626 FUNC    LOCAL  DEFAULT    2 e1000_clean_jumbo_rx_irq
   674: 0000000000018090  2013 FUNC    LOCAL  DEFAULT    2 e1000_clean_rx_irq_ps

This is the 3rd inline expansion of e1000_consume_page() in
e1000_clean_jumbo_rx_irq():

   <3><13ec77>: Abbrev Number: 119 (DW_TAG_inlined_subroutine)
    <13ec78>   DW_AT_abstract_origin: <0x13ed2c>
    <13ec7c>   DW_AT_low_pc      : 0x17f79

  0x17f79 - 0x17a30 = 1353

 So:

   0x17a30 + 2 * 1353 = 0x184c2

  And:

   0x184c2 - 0x18090 = 1074

Which explains the bogus third expansion for e1000_consume_page() to end up at:

   p:probe/e1000_consume_page_2 e1000e:e1000_clean_rx_irq_ps+1074

All fixed now :-)

[1] https://git.kernel.org/pub/scm/devel/pahole/pahole.git/

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 613f050d68 ("perf probe: Fix to probe on gcc generated functions in modules")
Link: http://lkml.kernel.org/r/20170621164134.5701-1-bjorn.topel@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-06-22 16:08:09 -03:00
Arnaldo Carvalho de Melo
8ec20b176c perf str{filter,list}: Disentangle headers
There are places where we just need a forward declaration, and others
were we need to include strlist.h and/or strfilter.h, reducing the
impact of changes in headers on the build time, do it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-zab42gbiki88y9k0csorxekb@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-19 13:01:52 -03:00
Arnaldo Carvalho de Melo
a067558e2f perf tools: Move extra string util functions to util/string2.h
Moving them from util.h, where they don't belong. Since libc already
have string.h, name it slightly differently, as string2.h.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-eh3vz5sqxsrdd8lodoro4jrw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-19 13:01:51 -03:00
Arnaldo Carvalho de Melo
3d689ed609 perf tools: Move sane ctype stuff from util.h to sane_ctype.h
More stuff that came from git, out of the hodge-podge that is util.h

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-e3lana4gctz3ub4hn4y29hkw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-19 13:01:48 -03:00
Arnaldo Carvalho de Melo
fd20e8111c perf tools: Including missing inttypes.h header
Needed to use the PRI[xu](32,64) formatting macros.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-wkbho8kaw24q67dd11q0j39f@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-19 13:01:46 -03:00
Ravi Bangoria
2e1f8f7895 perf probe: Change MAX_CMDLEN
There are many SDT markers in powerpc whose uprobe definition goes
beyond current MAX_CMDLEN, especially when target filename is long and
sdt marker has long list of arguments. For example, definition of sdt
marker

  method__compile__end: 8@17 8@9 8@10 -4@8 8@7 -4@6 8@5 -4@4 1@37(28)

from file

  /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.91-2.b14.fc22.ppc64/jre/lib/ppc64/server/libjvm.so

is

  p:sdt_hotspot/method__compile__end /usr/lib/jvm/java-1.8.0-openjdk-\
    1.8.0.91-2.b14.fc22.ppc64/jre/lib/ppc64/server/libjvm.so:0x4c4e00\
    arg1=%gpr17:u64 arg2=%gpr9:u64 arg3=%gpr10:u64 arg4=%gpr8:s32\
    arg5=%gpr7:u64 arg6=%gpr6:s32 arg7=%gpr5:u64 arg8=%gpr4:s32\
    arg9=+37(%gpr28):u8

'perf probe' fails with segfault for such markers. As the uprobe_events
file accepts definitions up to 4094 characters(4096 - 2 (\n\0)),
increase value of MAX_CMDLEN match that.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexis Berlemont <alexis.berlemont@gmail.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170207054547.3690-1-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-21 10:34:59 -03:00
Ravi Bangoria
f0a30dca5f perf probe: Fix concat_probe_trace_events
'*ntevs' contains number of elements present in 'tevs' array. If there
are no elements in array, 'tevs2' can be directly assigned to 'tevs'
without allocating more space. So the condition should be  '*ntevs == 0'
not  'ntevs == 0'.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: 42bba263eb ("perf probe: Allow wildcard for cached events")
Link: http://lkml.kernel.org/r/20170308065908.4128-1-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-20 15:01:32 -03:00
Ravi Bangoria
af9100ad14 perf probe: Introduce util func is_sdt_event()
Factor out the SDT event name checking routine as is_sdt_event().

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Taeung Song <treeze.taeung@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20170314150658.7065-2-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-15 17:48:37 -03:00
Naveen N. Rao
7ab31d94bf perf kretprobes: Offset from reloc_sym if kernel supports it
We indicate support for accepting sym+offset with kretprobes through a
line in ftrace README. Parse the same to identify support and choose the
appropriate format for kprobe_events.

As an example, without this perf patch, but with the ftrace changes:

  naveen@ubuntu:~/linux/tools/perf$ sudo cat /sys/kernel/debug/tracing/README | grep kretprobe
  place (kretprobe): [<module>:]<symbol>[+<offset>]|<memaddr>
  naveen@ubuntu:~/linux/tools/perf$
  naveen@ubuntu:~/linux/tools/perf$ sudo ./perf probe -v do_open%return
  probe-definition(0): do_open%return
  symbol:do_open file:(null) line:0 offset:0 return:1 lazy:(null)
  0 arguments
  Looking at the vmlinux_path (8 entries long)
  Using /boot/vmlinux for symbols
  Open Debuginfo file: /boot/vmlinux
  Try to find probe point from debuginfo.
  Matched function: do_open [2d0c7d8]
  Probe point found: do_open+0
  Matched function: do_open [35d76b5]
  found inline addr: 0xc0000000004ba984
  Failed to find "do_open%return",
   because do_open is an inlined function and has no return point.
  An error occurred in debuginfo analysis (-22).
  Trying to use symbols.
  Opening /sys/kernel/debug/tracing//kprobe_events write=1
  Writing event: r:probe/do_open do_open+0
  Writing event: r:probe/do_open_1 do_open+0
  Added new events:
    probe:do_open        (on do_open%return)
    probe:do_open_1      (on do_open%return)

  You can now use it in all perf tools, such as:

	  perf record -e probe:do_open_1 -aR sleep 1

  naveen@ubuntu:~/linux/tools/perf$ sudo cat /sys/kernel/debug/kprobes/list
  c000000000041370  k  kretprobe_trampoline+0x0    [OPTIMIZED]
  c0000000004433d0  r  do_open+0x0    [DISABLED]
  c0000000004433d0  r  do_open+0x0    [DISABLED]

And after this patch (and the subsequent powerpc patch):

  naveen@ubuntu:~/linux/tools/perf$ sudo ./perf probe -v do_open%return
  probe-definition(0): do_open%return
  symbol:do_open file:(null) line:0 offset:0 return:1 lazy:(null)
  0 arguments
  Looking at the vmlinux_path (8 entries long)
  Using /boot/vmlinux for symbols
  Open Debuginfo file: /boot/vmlinux
  Try to find probe point from debuginfo.
  Matched function: do_open [2d0c7d8]
  Probe point found: do_open+0
  Matched function: do_open [35d76b5]
  found inline addr: 0xc0000000004ba984
  Failed to find "do_open%return",
   because do_open is an inlined function and has no return point.
  An error occurred in debuginfo analysis (-22).
  Trying to use symbols.
  Opening /sys/kernel/debug/tracing//README write=0
  Opening /sys/kernel/debug/tracing//kprobe_events write=1
  Writing event: r:probe/do_open _text+4469712
  Writing event: r:probe/do_open_1 _text+4956248
  Added new events:
    probe:do_open        (on do_open%return)
    probe:do_open_1      (on do_open%return)

  You can now use it in all perf tools, such as:

	  perf record -e probe:do_open_1 -aR sleep 1

  naveen@ubuntu:~/linux/tools/perf$ sudo cat /sys/kernel/debug/kprobes/list
  c000000000041370  k  kretprobe_trampoline+0x0    [OPTIMIZED]
  c0000000004433d0  r  do_open+0x0    [DISABLED]
  c0000000004ba058  r  do_open+0x8    [DISABLED]

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/496ef9f33c1ab16286ece9dd62aa672807aef91c.1488961018.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-14 15:17:39 -03:00
Namhyung Kim
bb963e1650 perf utils: Check verbose flag properly
It now can have negative value to suppress the message entirely.  So it
needs to check it being positive.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170217081742.17417-3-namhyung@kernel.org
[ Adjust fuzz on tools/perf/util/pmu.c, add > 0 checks in many other places ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-02-20 11:35:54 -03:00
Arnaldo Carvalho de Melo
8a2efd6dd5 perf probe: Avoid accessing uninitialized 'map' variable
Genuine problem detected with clang, the warnings are spot on:

  util/probe-event.c:2079:7: error: variable 'map' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
                  if (addr) {
                      ^~~~
  util/probe-event.c:2094:6: note: uninitialized use occurs here
          if (map && !is_kprobe) {
              ^~~
  util/probe-event.c:2079:3: note: remove the 'if' if its condition is always true
                  if (addr) {
                  ^~~~~~~~~~
  util/probe-event.c:2075:8: error: variable 'map' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
                          if (kernel_get_symbol_address_by_name(tp->symbol,
                              ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  util/probe-event.c:2094:6: note: uninitialized use occurs here
          if (map && !is_kprobe) {
              ^~~
  util/probe-event.c:2075:4: note: remove the 'if' if its condition is always false
                          if (kernel_get_symbol_address_by_name(tp->symbol,
                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  util/probe-event.c:2064:17: note: initialize the variable 'map' to silence this warning
          struct map *map;
                         ^
                          = NULL

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-m3501el55i10hctfbmi2qxzr@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-02-14 15:28:41 -03:00
Ingo Molnar
e2cf00c257 New features:
- Introduce 'perf ftrace' a perf front end to the kernel's ftrace
   function and function_graph tracer, defaulting to the "function_graph"
   tracer, more work will be done in reviving this effort, forward porting
   it from its initial patch submission (Namhyung Kim)
 
 - Add 'e' and 'c' hotkeys to expand/collapse call chains for a single
   hist entry in the 'perf report' and 'perf top' TUI (Jiri Olsa)
 
 Fixes:
 
 - Fix wrong register name for arm64, used in 'perf probe' (He Kuang)
 
 - Fix map offsets in relocation in libbpf (Joe Stringer)
 
 - Fix looking up dwarf unwind stack info (Matija Glavinic Pecotic)
 
 Infrastructure:
 
 - libbpf prog functions sync with what is exported via uapi (Joe Stringer)
 
 Trivial:
 
 - Remove unnecessary checks and assignments in 'perf probe's
   try_to_find_absolute_address() (Markus Elfring)
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo-4.11-20170126' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull the latest perf/core updates from Arnaldo Carvalho de Melo:

New features:

 - Introduce 'perf ftrace' a perf front end to the kernel's ftrace
   function and function_graph tracer, defaulting to the "function_graph"
   tracer, more work will be done in reviving this effort, forward porting
   it from its initial patch submission (Namhyung Kim)

 - Add 'e' and 'c' hotkeys to expand/collapse call chains for a single
   hist entry in the 'perf report' and 'perf top' TUI (Jiri Olsa)

Fixes:

 - Fix wrong register name for arm64, used in 'perf probe' (He Kuang)

 - Fix map offsets in relocation in libbpf (Joe Stringer)

 - Fix looking up dwarf unwind stack info (Matija Glavinic Pecotic)

Infrastructure changes:

 - libbpf prog functions sync with what is exported via uapi (Joe Stringer)

Trivial changes:

 - Remove unnecessary checks and assignments in 'perf probe's
   try_to_find_absolute_address() (Markus Elfring)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-26 16:20:59 +01:00
Markus Elfring
d1d0e29cb7 perf probe: Delete an unnecessary assignment in try_to_find_absolute_address()
Remove an error code assignment which is redundant in an if branch for
the handling of a memory allocation failure because the same value was
set for the local variable "err" before.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: kernel-janitors@vger.kernel.org
Link: http://lkml.kernel.org/r/0ede09ec-79b6-c8bd-5b20-02c63ed98aab@users.sourceforge.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-26 11:42:56 -03:00
Markus Elfring
42e233cacc perf probe: Delete an unnecessary check in try_to_find_absolute_address()
Remove a condition check which is unnecessary at the end
because this source code place should usually only be reached
with a non-zero pointer.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: kernel-janitors@vger.kernel.org
Link: http://lkml.kernel.org/r/a3f2473b-6383-a326-bce0-b826423608b8@users.sourceforge.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-26 11:42:55 -03:00
Masami Hiramatsu
613f050d68 perf probe: Fix to probe on gcc generated functions in modules
Fix to probe on gcc generated functions on modules. Since
probing on a module is based on its symbol name, it should
be adjusted on actual symbols.

E.g. without this fix, perf probe shows probe definition
on non-exist symbol as below.

  $ perf probe -m build-x86_64/net/netfilter/nf_nat.ko -F in_range*
  in_range.isra.12
  $ perf probe -m build-x86_64/net/netfilter/nf_nat.ko -D in_range
  p:probe/in_range nf_nat:in_range+0

With this fix, perf probe correctly shows a probe on
gcc-generated symbol.

  $ perf probe -m build-x86_64/net/netfilter/nf_nat.ko -D in_range
  p:probe/in_range nf_nat:in_range.isra.12+0

This also fixes same problem on online module as below.

  $ perf probe -m i915 -D assert_plane
  p:probe/assert_plane i915:assert_plane.constprop.134+0

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/148411450673.9978.14905987549651656075.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-16 15:43:04 -03:00
Masami Hiramatsu
3e96dac7c9 perf probe: Add error checks to offline probe post-processing
Add error check codes on post processing and improve it for offline
probe events as:

 - post processing fails if no matched symbol found in map(-ENOENT)
   or strdup() failed(-ENOMEM).

 - Even if the symbol name is the same, it updates symbol address
   and offset.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/148411443738.9978.4617979132625405545.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-16 15:35:25 -03:00
Masami Hiramatsu
8a937a25a7 perf probe: Fix to probe on gcc generated symbols for offline kernel
Fix perf-probe to show probe definition on gcc generated symbols for
offline kernel (including cross-arch kernel image).

gcc sometimes optimizes functions and generate new symbols with suffixes
such as ".constprop.N" or ".isra.N" etc. Since those symbol names are
not recorded in DWARF, we have to find correct generated symbols from
offline ELF binary to probe on it (kallsyms doesn't correct it).  For
online kernel or uprobes we don't need it because those are rebased on
_text, or a section relative address.

E.g. Without this:

  $ perf probe -k build-arm/vmlinux -F __slab_alloc*
  __slab_alloc.constprop.9
  $ perf probe -k build-arm/vmlinux -D __slab_alloc
  p:probe/__slab_alloc __slab_alloc+0

If you put above definition on target machine, it should fail
because there is no __slab_alloc in kallsyms.

With this fix, perf probe shows correct probe definition on
__slab_alloc.constprop.9:

  $ perf probe -k build-arm/vmlinux -D __slab_alloc
  p:probe/__slab_alloc __slab_alloc.constprop.9+0

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/148350060434.19001.11864836288580083501.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-04 11:44:22 -03:00
Masami Hiramatsu
eebc509b20 perf probe: Fix --funcs to show correct symbols for offline module
Fix --funcs (-F) option to show correct symbols for offline module.
Since previous perf-probe uses machine__findnew_module_map() for offline
module, even if user passes a module file (with full path) which is for
other architecture, perf-probe always tries to load symbol map for
current kernel module.

This fix uses dso__new_map() to load the map from given binary as same
as a map for user applications.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/148350053478.19001.15435255244512631545.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-04 11:15:09 -03:00
Masami Hiramatsu
1f2ed153b9 perf probe: Fix to get correct modname from elf header
Since 'perf probe' supports cross-arch probes, it is possible to analyze
different arch kernel image which has different bits-per-long.

In that case, it fails to get the module name because it uses the
MOD_NAME_OFFSET macro based on the host machine bits-per-long, instead
of the target arch bits-per-long.

This fixes above issue by changing modname-offset based on the target
archs bit width. This is ok because linux kernel uses LP64 model on
64bit arch.

E.g. without this (on x86_64, and target module is arm32):

  $ perf probe -m build-arm/fs/configfs/configfs.ko -D configfs_lookup
  p:probe/configfs_lookup :configfs_lookup+0
                          ^-Here is an empty module name.

With this fix, you can see correct module name:

  $ perf probe -m build-arm/fs/configfs/configfs.ko -D configfs_lookup
  p:probe/configfs_lookup configfs:configfs_lookup+0

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/148337043836.6752.383495516397005695.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-01-02 14:09:17 -03:00
Colin Ian King
ead1a57457 perf probe: Check if *ptr2 is zero and not ptr2
Static anaylsis with cppcheck[1] detected an incorrect comparison:
[tools/perf/util/probe-event.c:216]: (warning) Char literal compared
with pointer 'ptr2'. Did you intend to dereference it?

Dereference ptr2 for the comparison to fix this.

1: https://sourceforge.net/p/cppcheck/wiki/Home/

Signed-off-by: Colin King <colin.king@canonical.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 35726d3a4c ("perf probe: Fix to cut off incompatible chars from group name")
Link: http://lkml.kernel.org/r/20161003103431.18534-1-colin.king@canonical.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-10-03 11:24:12 -03:00
Masami Hiramatsu
35726d3a4c perf probe: Fix to cut off incompatible chars from group name
Cut off the characters which can not use for group name of uprobes
when making it based on executable filename.

For example, if the exec name is libstdc++.so, without this fix
perf probe generates "probe_libstdc++" as the group name, but
it is failed to set because '+' can not be used for group name.

With this fix perf accepts only alphabet, number or '_' for group
name, thus perf generates "probe_libstdc" as the group name.

E.g. with this fix, you can see the event name has no "+".
  ----
  $ ./perf probe -x /usr/lib64/libstdc++.so.6 -D is_open
  p:probe_libstdc/is_open /usr/lib64/libstdc++.so.6.0.22:0x8ca80
  p:probe_libstdc/is_open_1 /usr/lib64/libstdc++.so.6.0.22:0x8ca70
  p:probe_libstdc/is_open_2 /usr/lib64/libstdc++.so.6.0.22:0x8ca60
  p:probe_libstdc/is_open_3 /usr/lib64/libstdc++.so.6.0.22:0xb0ad0
  p:probe_libstdc/is_open_4 /usr/lib64/libstdc++.so.6.0.22:0xecca9
  ----

Committer note:

Before this fix:

  # perf probe -x /usr/lib64/libstdc++.so.6 is_open
  Failed to write event: Invalid argument
    Error: Failed to add events.
  #

After the fix:

  # perf probe -x /usr/lib64/libstdc++.so.6 is_open
  Added new events:
    probe_libstdc:is_open (on is_open in /usr/lib64/libstdc++.so.6.0.22)
    probe_libstdc:is_open_1 (on is_open in /usr/lib64/libstdc++.so.6.0.22)
    probe_libstdc:is_open_2 (on is_open in /usr/lib64/libstdc++.so.6.0.22)
    probe_libstdc:is_open_3 (on is_open in /usr/lib64/libstdc++.so.6.0.22)
    probe_libstdc:is_open_4 (on is_open in /usr/lib64/libstdc++.so.6.0.22)

  You can now use it in all perf tools, such as:

	  perf record -e probe_libstdc:is_open_4 -aR sleep 1

  # perf probe -l probe_libstdc:*
    probe_libstdc:is_open (on is_open@libstdc++-v3/include/fstream in /usr/lib64/libstdc++.so.6.0.22)
    probe_libstdc:is_open_1 (on is_open@libstdc++-v3/include/fstream in /usr/lib64/libstdc++.so.6.0.22)
    probe_libstdc:is_open_2 (on is_open@libstdc++-v3/include/fstream in /usr/lib64/libstdc++.so.6.0.22)
    probe_libstdc:is_open_3 (on is_open@src/c++98/basic_file.cc in /usr/lib64/libstdc++.so.6.0.22)
    probe_libstdc:is_open_4 (on stdio_filebuf:5@include/ext/stdio_filebuf.h in /usr/lib64/libstdc++.so.6.0.22)
  #

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/147464491667.29804.9553638175441827970.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-09-29 11:17:08 -03:00
Arnaldo Carvalho de Melo
be39db9f29 perf symbols: Remove symbol_filter_t machinery
We're not using it anymore, few users were, but we really could do
without it, simplify lots of functions by removing it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-1zng8wdznn00iiz08bb7q3vn@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-09-05 11:14:50 -03:00
Ravi Bangoria
b3f33f9306 perf probe: Add helper function to check if probe with variable
Introduce helper function instead of inline code and replace hardcoded
strings "$vars" and "$params" with their corresponding macros.

perf_probe_with_var() is not declared as static since it will be called
from different file in subsequent patch.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1470214725-5023-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-09-01 12:42:25 -03:00
Masami Hiramatsu
428aff82e9 perf probe: Ignore vmlinux buildid if offline kernel is given
Ignore the buildid of running kernel when both of --definition and
--vmlinux is given because that kernel should be off-line.

This also skips post-processing of kprobe event for relocating symbol
and checking blacklist, because it can not be done on off-line kernel.

E.g. without this fix perf shows an error as below
  ----
  $ perf probe --vmlinux=./vmlinux-arm --definition do_sys_open
  ./vmlinux-arm with build id 7a1f76dd56e9c4da707cd3d6333f50748141434b not found, continuing without symbols
  Failed to find symbol do_sys_open in kernel
    Error: Failed to add events.
  ----
with this fix, we can get the definition
  ----
  $ perf probe --vmlinux=./vmlinux-arm --definition do_sys_open
  p:probe/do_sys_open do_sys_open+0
  ----

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/147214228193.23638.12581984840822162131.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-09-01 09:44:14 -03:00
Masami Hiramatsu
1c20b1d154 perf probe: Show trace event definition
Add --definition/-D option for showing the trace-event definition in
stdout. This can be useful in debugging or combined with a shell script.

e.g.
  ----
  # perf probe --definition 'do_sys_open $params'
  p:probe/do_sys_open _text+2261728 dfd=%di:s32 filename=%si:u64 flags=%dx:s32 mode=%cx:u16
  ----

Suggested-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/147214226712.23638.2240534040014013658.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-09-01 09:44:13 -03:00
Arnaldo Carvalho de Melo
fd2275984d perf probe: Do not use map_load filters for function
It is simpler to just do the loop, no need for globals and the last user
of such facility disappears.

Testing:

  # perf probe -F [a-z]*recvmsg
  aead_recvmsg
  compat_SyS_recvmsg
  compat_sys_recvmsg
  hash_recvmsg
  inet_recvmsg
  kernel_recvmsg
  netlink_recvmsg
  packet_recvmsg
  ping_recvmsg
  raw_recvmsg
  rawv6_recvmsg
  rng_recvmsg
  security_socket_recvmsg
  selinux_socket_recvmsg
  skcipher_recvmsg
  sock_common_recvmsg
  sock_no_recvmsg
  sock_recvmsg
  sys_recvmsg
  tcp_recvmsg
  udp_recvmsg
  udpv6_recvmsg
  unix_dgram_recvmsg
  unix_seqpacket_recvmsg
  unix_stream_recvmsg
  #

Without filters:

  # perf probe -F | tail -5
  zswap_pool_create
  zswap_pool_current
  zswap_update_total_size
  zswap_writeback_entry
  zswap_zpool_param_set
  #
  # perf probe -F | wc -l
  33311
  #

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20160831130427.GA13095@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-09-01 09:43:57 -03:00
Ravi Bangoria
99e608b595 perf probe ppc64le: Fix probe location when using DWARF
Powerpc has Global Entry Point and Local Entry Point for functions.  LEP
catches call from both the GEP and the LEP. Symbol table of ELF contains
GEP and Offset from which we can calculate LEP, but debuginfo does not
have LEP info.

Currently, perf prioritize symbol table over dwarf to probe on LEP for
ppc64le. But when user tries to probe with function parameter, we fall
back to using dwarf(i.e. GEP) and when function called via LEP, probe
will never hit.

For example:

  $ objdump -d vmlinux
    ...
    do_sys_open():
    c0000000002eb4a0:       e8 00 4c 3c     addis   r2,r12,232
    c0000000002eb4a4:       60 00 42 38     addi    r2,r2,96
    c0000000002eb4a8:       a6 02 08 7c     mflr    r0
    c0000000002eb4ac:       d0 ff 41 fb     std     r26,-48(r1)

  $ sudo ./perf probe do_sys_open
  $ sudo cat /sys/kernel/debug/tracing/kprobe_events
    p:probe/do_sys_open _text+3060904

  $ sudo ./perf probe 'do_sys_open filename:string'
  $ sudo cat /sys/kernel/debug/tracing/kprobe_events
    p:probe/do_sys_open _text+3060896 filename_string=+0(%gpr4):string

For second case, perf probed on GEP. So when function will be called via
LEP, probe won't hit.

  $ sudo ./perf record -a -e probe:do_sys_open ls
    [ perf record: Woken up 1 times to write data ]
    [ perf record: Captured and wrote 0.195 MB perf.data ]

To resolve this issue, let's not prioritize symbol table, let perf
decide what it wants to use. Perf is already converting GEP to LEP when
it uses symbol table. When perf uses debuginfo, let it find LEP offset
form symbol table. This way we fall back to probe on LEP for all cases.

After patch:

  $ sudo ./perf probe 'do_sys_open filename:string'
  $ sudo cat /sys/kernel/debug/tracing/kprobe_events
    p:probe/do_sys_open _text+3060904 filename_string=+0(%gpr4):string

  $ sudo ./perf record -a -e probe:do_sys_open ls
    [ perf record: Woken up 1 times to write data ]
    [ perf record: Captured and wrote 0.197 MB perf.data (11 samples) ]

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1470723805-5081-2-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-08-09 12:14:29 -03:00
Ravi Bangoria
d820456dc7 perf probe: Add function to post process kernel trace events
Instead of inline code, introduce function to post process kernel
probe trace events.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1470723805-5081-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-08-09 12:09:59 -03:00
Konstantin Khlebnikov
cb3f3378cd perf probe: Fix module name matching
If module is "module" then dso->short_name is "[module]".  Substring
comparing is't enough: "raid10" matches to "[raid1]".  This patch also
checks terminating zero in module name.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: http://lkml.kernel.org/r/147039975648.715620.12985971832789032159.stgit@buzz
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-08-09 10:48:09 -03:00
Masami Hiramatsu
8e34189b34 perf probe: Adjust map->reloc offset when finding kernel symbol from map
Adjust map->reloc offset for the unmapped address when finding
alternative symbol address from map, because KASLR can relocate the
kernel symbol address.

The same adjustment has been done when finding appropriate kernel symbol
address from map which was introduced by commit f90acac757 ("perf
probe: Find given address from offline dwarf")

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu@linaro.org>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20160806192948.e366f3fbc4b194de600f8326@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-08-09 10:47:43 -03:00
Masami Hiramatsu
e70493429b perf probe: Warn unmatched function filter correctly
Warn unmatched function filter correctly instead of warning
"symbol-loading error", since that can be a filter issue.

From the technical point of view, this adds a filter chech in map__load
and if there is a filter, it returns -2 (filter-out), instead of -1
(error), and perf-probe checks it and change message.

E.g. without this fix:

  # perf probe -F rt_sp*
  no symbols found in [kernel.kallsyms], maybe install a debug package?
  Failed to load symbols in kernel

With this fix:

  # perf probe -F rt_sp*
  no symbols passed the given filter.
  Failed to find symbols matched to "rt_sp*"
    Error: Failed to show functions.

Reported-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/146885835596.16106.2293540792775552481.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-18 19:46:34 -03:00
Masami Hiramatsu
7e9fca51fb perf probe: Support a special SDT probe format
Support a special SDT probe format which can omit the '%' prefix only if
the SDT group name starts with "sdt_". So, for example both of
"%sdt_libc:setjump" and "sdt_libc:setjump" are acceptable for perf probe
--add.

E.g. without this:

  # perf probe -a sdt_libc:setjmp
  Semantic error :There is non-digit char in line number.
  ...

With this:

  # perf probe -a sdt_libc:setjmp
  Added new event:
    sdt_libc:setjmp      (on %setjmp in /usr/lib64/libc-2.20.so)

  You can now use it in all perf tools, such as:

  	perf record -e sdt_libc:setjmp -aR sleep 1

Suggested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/146831794674.17065.13359473252168740430.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-13 23:09:09 -03:00
Masami Hiramatsu
a598180aa1 perf probe: Support @BUILDID or @FILE suffix for SDT events
Support @BUILDID or @FILE suffix for SDT events. This allows perf to add
probes on SDTs/pre-cached events on given FILE or the file which has
given BUILDID (also, this complements BUILDID.)

For example, both gcc and libstdc++ has same SDTs as below.  If you
would like to add a probe on sdt_libstdcxx:catch on gcc, you can do as
below.

  ----
  # perf list sdt | tail -n 6
    sdt_libstdcxx:catch@/usr/bin/gcc(0cc207fc4b27)     [SDT event]
    sdt_libstdcxx:catch@/usr/lib64/libstdc++.so.6.0.20(91c7a88fdf49)
    sdt_libstdcxx:rethrow@/usr/bin/gcc(0cc207fc4b27)   [SDT event]
    sdt_libstdcxx:rethrow@/usr/lib64/libstdc++.so.6.0.20(91c7a88fdf49)
    sdt_libstdcxx:throw@/usr/bin/gcc(0cc207fc4b27)     [SDT event]
    sdt_libstdcxx:throw@/usr/lib64/libstdc++.so.6.0.20(91c7a88fdf49)
  # perf probe -a %sdt_libstdcxx:catch@0cc
  Added new event:
    sdt_libstdcxx:catch  (on %catch in /usr/bin/gcc)

  You can now use it in all perf tools, such as:

  	perf record -e sdt_libstdcxx:catch -aR sleep 1
  ----

Committer note:

Doing the full sequence of steps to get the results above:

With a clean build-id cache:

  [root@jouet ~]# rm -rf ~/.debug/
  [root@jouet ~]# perf list sdt

  List of pre-defined events (to be used in -e):

  [root@jouet ~]#

No events whatsoever, then, we can add all events in gcc to the build-id
cache, doing a --add + --dry-run:

  [root@jouet ~]# perf probe --dry-run --cache -x /usr/bin/gcc --add %sdt_libstdcxx:\*
  Added new events:
    sdt_libstdcxx:throw  (on %* in /usr/bin/gcc)
    sdt_libstdcxx:rethrow (on %* in /usr/bin/gcc)
    sdt_libstdcxx:catch  (on %* in /usr/bin/gcc)

  You can now use it in all perf tools, such as:

	perf record -e sdt_libstdcxx:catch -aR sleep 1

  [root@jouet ~]#

It really didn't add any events, it just cached them:

  [root@jouet ~]# perf probe -l
  [root@jouet ~]#

We can see that it was cached as:

  [root@jouet ~]# ls -la ~/.debug/usr/bin/gcc/9a0730e2bcc6d2a2003d21ac46807e8ee6bcb7c2/
  total 976
  drwxr-xr-x. 2 root root   4096 Jul 13 21:47 .
  drwxr-xr-x. 3 root root   4096 Jul 13 21:47 ..
  -rwxr-xr-x. 4 root root 985912 Jun 22 18:52 elf
  -rw-r--r--. 1 root root    303 Jul 13 21:47 probes
  [root@jouet ~]# file ~/.debug/usr/bin/gcc/9a0730e2bcc6d2a2003d21ac46807e8ee6bcb7c2/elf
  /root/.debug/usr/bin/gcc/9a0730e2bcc6d2a2003d21ac46807e8ee6bcb7c2/elf: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 2.6.32, BuildID[sha1]=9a0730e2bcc6d2a2003d21ac46807e8ee6bcb7c2, stripped
  [root@jouet ~]# cat ~/.debug/usr/bin/gcc/9a0730e2bcc6d2a2003d21ac46807e8ee6bcb7c2/probes
  %sdt_libstdcxx:throw=throw
  p:sdt_libstdcxx/throw /usr/bin/gcc:0x71ffd
  %sdt_libstdcxx:rethrow=rethrow
  p:sdt_libstdcxx/rethrow /usr/bin/gcc:0x720b8
  %sdt_libstdcxx:catch=catch
  p:sdt_libstdcxx/catch /usr/bin/gcc:0x7307f
  %sdt_libgcc:unwind=unwind
  p:sdt_libgcc/unwind /usr/bin/gcc:0x7eec0
  #sdt_libstdcxx:*=%*
  [root@jouet ~]#

Ok, now we can use 'perf probe' to refer to those cached entries as:

  Humm, nope, doing as above we end up with:

  [root@jouet ~]# perf probe -a %sdt_libstdcxx:catch
  Semantic error :* is bad for event name -it must follow C symbol-naming rule.
    Error: Failed to add events.
  [root@jouet ~]#

But it worked at some point, lets try not using --dry-run:

Resetting everything:

  # rm -rf ~/.debug/
  # perf probe -d *:*
  # perf probe -l
  # perf list sdt

    List of pre-defined events (to be used in -e):

  #

Ok, now it cached everything, even things we haven't asked it to
(sdt_libgcc:unwind):

  [root@jouet ~]# perf probe -x /usr/bin/gcc --add %sdt_libstdcxx:\*
  Added new events:
    sdt_libstdcxx:throw  (on %* in /usr/bin/gcc)
    sdt_libstdcxx:rethrow (on %* in /usr/bin/gcc)
    sdt_libstdcxx:catch  (on %* in /usr/bin/gcc)

  You can now use it in all perf tools, such as:

	perf record -e sdt_libstdcxx:catch -aR sleep 1

  [root@jouet ~]# perf list sdt

  List of pre-defined events (to be used in -e):

    sdt_libgcc:unwind                                  [SDT event]
    sdt_libstdcxx:catch                                [SDT event]
    sdt_libstdcxx:rethrow                              [SDT event]
    sdt_libstdcxx:throw                                [SDT event]
  [root@jouet ~]#

And we have the events in place:

  [root@jouet ~]# perf probe -l
    sdt_libstdcxx:catch  (on execute_cfa_program+1551@../../../libgcc/unwind-dw2.c in /usr/bin/gcc)
    sdt_libstdcxx:rethrow (on d_print_subexpr+280@libsupc++/cp-demangle.c in /usr/bin/gcc)
    sdt_libstdcxx:throw  (on d_print_subexpr+93@libsupc++/cp-demangle.c in /usr/bin/gcc)
  [root@jouet ~]#

And trying to use them at least has 'perf trace --event sdt*:*' working.

Then, if we try to add the ones in libstdc++:

  [root@jouet ~]# perf probe -x /usr/lib64/libstdc++.so.6 -a %sdt_libstdcxx:\*
  Error: event "catch" already exists.
   Hint: Remove existing event by 'perf probe -d'
         or force duplicates by 'perf probe -f'
         or set 'force=yes' in BPF source.
    Error: Failed to add events.
  [root@jouet ~]#

Doesn't work, dups, but at least this served to, unbeknownst to the user, add
the SDT probes in /usr/lib64/libstdc++.so.6!

  [root@jouet ~]# perf list sdt

  List of pre-defined events (to be used in -e):

    sdt_libgcc:unwind                                  [SDT event]
    sdt_libstdcxx:catch@/usr/bin/gcc(9a0730e2bcc6)     [SDT event]
    sdt_libstdcxx:catch@/usr/lib64/libstdc++.so.6.0.22(ef2b7066559a) [SDT event]
    sdt_libstdcxx:rethrow@/usr/bin/gcc(9a0730e2bcc6)   [SDT event]
    sdt_libstdcxx:rethrow@/usr/lib64/libstdc++.so.6.0.22(ef2b7066559a) [SDT event]
    sdt_libstdcxx:throw@/usr/bin/gcc(9a0730e2bcc6)     [SDT event]
    sdt_libstdcxx:throw@/usr/lib64/libstdc++.so.6.0.22(ef2b7066559a) [SDT event]
  [root@jouet ~]#

Now we should be able to get to the original cset comment, if we remove all
SDTs events in place, not from the cache, from the kernel, where it was set up as:

  [root@jouet ~]# ls -la /sys/kernel/debug/tracing/events/sdt_libstdcxx/
  total 0
  drwxr-xr-x.  5 root root 0 Jul 13 22:00 .
  drwxr-xr-x. 80 root root 0 Jul 13 21:56 ..
  drwxr-xr-x.  2 root root 0 Jul 13 22:00 catch
  -rw-r--r--.  1 root root 0 Jul 13 22:00 enable
  -rw-r--r--.  1 root root 0 Jul 13 22:00 filter
  drwxr-xr-x.  2 root root 0 Jul 13 22:00 rethrow
  drwxr-xr-x.  2 root root 0 Jul 13 22:00 throw
  [root@jouet ~]#

  [root@jouet ~]# head -2 /sys/kernel/debug/tracing/events/sdt_libstdcxx/throw/format
  name: throw
  ID: 2059
  [root@jouet ~]#

Now to remove it:

  [root@jouet ~]# perf probe -d sdt_libstdc*:*
  Removed event: sdt_libstdcxx:catch
  Removed event: sdt_libstdcxx:rethrow
  Removed event: sdt_libstdcxx:throw
  [root@jouet ~]#

Which caused:

  [root@jouet ~]# ls -la /sys/kernel/debug/tracing/events/sdt_libstdcxx/
  ls: cannot access '/sys/kernel/debug/tracing/events/sdt_libstdcxx/': No such file or directory
  [root@jouet ~]#

Ok, now we can do:

  [root@jouet ~]# perf list sdt_libstdcxx:catch

  List of pre-defined events (to be used in -e):

    sdt_libstdcxx:catch@/usr/bin/gcc(9a0730e2bcc6)     [SDT event]
    sdt_libstdcxx:catch@/usr/lib64/libstdc++.so.6.0.22(ef2b7066559a) [SDT event]
  [root@jouet ~]#

So, these are not really 'pre-defined events', i.e. we can't use them with
'perf record --event':

  [root@jouet ~]# perf record --event sdt_libstdcxx:catch*
  event syntax error: 'sdt_libstdcxx:catch*'
                       \___ unknown tracepoint

  Error:	File /sys/kernel/debug/tracing/events/sdt_libstdcxx/catch* not found.
  Hint:	Perhaps this kernel misses some CONFIG_ setting to enable this feature?.
<SNIP>
  [root@jouet ~]#

To have it really pre-defined we must use perf probe to get its definition from
the cache and set it up in the kernel, creating the tracepoint to _then_ use it
with 'perf record --event':

  [root@jouet ~]# perf probe -a sdt_libstdcxx:catch
  Semantic error :There is non-digit char in line number.
  <SNIP>

Oops, there is another gotcha here, we need that pesky '%' character:

  [root@jouet ~]# perf probe -a %sdt_libstdcxx:catch
  Added new events:
    sdt_libstdcxx:catch  (on %catch in /usr/bin/gcc)
    sdt_libstdcxx:catch_1 (on %catch in /usr/lib64/libstdc++.so.6.0.22)

  You can now use it in all perf tools, such as:

	perf record -e sdt_libstdcxx:catch_1 -aR sleep 1

  [root@jouet ~]#

But then we added _two_ events, one with the name we expected, the other one
with a _ added, when doing the analysis we need to pay attention to who maps to
who.

And here is where we get to the point of this patch, which is to be able to
disambiguate those definitions for 'catch' in the build-id cache, but first we need
remove those events we just added:

[root@jouet ~]# perf probe -d %sdt_libstdcxx:catch

Oops, that didn't remove anything, we need to _remove_ that % char in this case:

  [root@jouet ~]# perf probe -d sdt_libstdcxx:catch
  Removed event: sdt_libstdcxx:catch

And we need to remove the other event added, i.e. I forgot to add a * at the end:

  [root@jouet ~]# perf probe -d sdt_libstdcxx:catch*
  Removed event: sdt_libstdcxx:catch_1
  [root@jouet ~]#

Ok, disambiguating it using what is in this patch:

  [root@jouet ~]# perf list sdt_libstdcxx:catch

  List of pre-defined events (to be used in -e):

    sdt_libstdcxx:catch@/usr/bin/gcc(9a0730e2bcc6)     [SDT event]
    sdt_libstdcxx:catch@/usr/lib64/libstdc++.so.6.0.22(ef2b7066559a) [SDT event]
  [root@jouet ~]#
  [root@jouet ~]# perf probe -a %sdt_libstdcxx:catch@9a07
  Added new event:
    sdt_libstdcxx:catch  (on %catch in /usr/bin/gcc)

  You can now use it in all perf tools, such as:

	perf record -e sdt_libstdcxx:catch -aR sleep 1

  [root@jouet ~]# perf probe -l
    sdt_libstdcxx:catch  (on execute_cfa_program+1551@../../../libgcc/unwind-dw2.c in /usr/bin/gcc)
  [root@jouet ~]#

Yeah, it works! But we need to try and simplify this :-)

Update: Some aspects of this simplification take place in the following
        patches.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/146831793746.17065.13065062753978236612.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-13 23:09:08 -03:00
Masami Hiramatsu
1de7b8bf72 perf probe: Search SDT/cached event from all probe caches
Search SDT/cached event from all probe caches if user doesn't pass any
binary. With this, we don't have to specify target binary for SDT and
named cached events (which start with %).

E.g. without this, a target binary must be passed with -x.

  # perf probe -x /usr/lib64/libc-2.20.so -a %sdt_libc:\*

With this change, we don't need it anymore.

  # perf probe -a %sdt_libc:\*

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/146831792812.17065.2353705982669445313.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-13 23:09:07 -03:00
Masami Hiramatsu
42bba263eb perf probe: Allow wildcard for cached events
Allo glob wildcard for reusing cached/SDT events. E.g.

  # perf probe -x /usr/lib64/libc-2.20.so -a %sdt_libc:\*

This example adds probes for all SDT in libc.
Note that the SDTs must have been scanned by perf buildid-cache.

Committer note:

Using it to check what of those SDT probes would take place when doing
a cargo run (rust):

  # trace --no-sys --event sdt_libc:* cargo run
     0.000 sdt_libc:setjmp:(7f326b69c4d1))
    28.423 sdt_libc:setjmp:(7f4b0a5364d1))
    29.000 sdt_libc:setjmp:(7f4b0a5364d1))
    88.597 sdt_libc:setjmp:(7fc01fd414d1))
    89.220 sdt_libc:setjmp:(7fc01fd414d1))
    95.501 sdt_libc:setjmp:(7f326b69c4d1))
     Running `target/debug/hello_world`
    97.110 sdt_libc:setjmp:(7f95e09234d1))
  Hello, world!
  #

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/146831791813.17065.17846564230840594888.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-13 23:09:07 -03:00
Masami Hiramatsu
36a009fe07 perf probe: Accept %sdt and %cached event name
To improve usability, support %[PROVIDER:]SDTEVENT format to add new
probes on SDT and cached events.

e.g.
  ----
  # perf probe -x /lib/libc-2.17.so  %lll_lock_wait_private
  Added new event:
    sdt_libc:lll_lock_wait_private (on %lll_lock_wait_private in /usr/lib/libc-2.17.so)

  You can now use it in all perf tools, such as:

          perf record -e sdt_libc:lll_lock_wait_private -aR sleep 1

  # perf probe -l | more
    sdt_libc:lll_lock_wait_private (on __lll_lock_wait_private+21 in /usr/lib/libc-2.17.so)
  ----

Note that this is not only for SDT events, but also normal
events with event-name.

e.g. define "myevent" on cache (-n doesn't add the real probe)
  ----
  # perf probe -x ./perf --cache -n --add 'myevent=dso__load $params'
  ----
  Reuse the "myevent" from cache as below.
  ----
  # perf probe -x ./perf %myevent
  ----

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/146831788372.17065.3645054540325909346.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-13 23:09:05 -03:00
Masami Hiramatsu
f6eb0518f3 perf probe: Fix to show correct error message for $vars and $params
Fix to show correct error messages for $vars and $params because
those special variables requires debug information to find the
real variables or function parameters.

E.g. without this fix;
  ----
  # perf probe -x /lib64/libc-2.23.so getaddrinfo \$params
  Failed to write event: Invalid argument
  Please upgrade your kernel to at least 3.14 to have access to feature $params
    Error: Failed to add events.
  ----

Perf ends up with an error, but the message is not correct.  With this
fix, perf shows correct error message as below.

  ----
  # perf probe -x /lib64/libc-2.23.so getaddrinfo \$params
  The /usr/lib64/libc-2.23.so file has no debug information.
  Rebuild with -g, or install an appropriate debuginfo package.
    Error: Failed to add events.
  ----

Reported-and-Tested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/146831787438.17065.6152436996780110699.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-13 23:09:04 -03:00
Arnaldo Carvalho de Melo
c8b5f2c96d tools: Introduce str_error_r()
The tools so far have been using the strerror_r() GNU variant, that
returns a string, be it the buffer passed or something else.

But that, besides being tricky in cases where we expect that the
function using strerror_r() returns the error formatted in a provided
buffer (we have to check if it returned something else and copy that
instead), breaks the build on systems not using glibc, like Alpine
Linux, where musl libc is used.

So, introduce yet another wrapper, str_error_r(), that has the GNU
interface, but uses the portable XSI variant of strerror_r(), so that
users rest asured that the provided buffer is used and it is what is
returned.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-d4t42fnf48ytlk8rjxs822tf@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-12 15:19:47 -03:00
Masami Hiramatsu
8d993d9690 perf probe: Add group name support
Allow user to set group name for adding new event.  Note that user must
ensure that the group name doesn't conflict with existing group name
carefully.

E.g. Existing group name can conflict with other events.  Especially,
using the group name reserved for kernel modules can hide kernel
embedded events when loading modules.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/146736024091.27797.9471545190066268995.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-04 19:39:00 -03:00
Masami Hiramatsu
1f3736c9c8 perf probe: Show all cached probes
perf probe --list shows all cached probes when --cache is given. Each
caches are shown with on which binary that probed. E.g.:

  -----
  # perf probe --cache vfs_read \$params
  # perf probe --cache -x /lib64/libc-2.17.so getaddrinfo \$params
  # perf probe --cache --list
  [kernel.kallsyms] (1466a0a250b5d0070c6d0f03c5fed30b237970a1):
  vfs_read $params
  /usr/lib64/libc-2.17.so (c31ffe7942bfd77b2fca8f9bd5709d387a86d3bc):
  getaddrinfo $params
  -----

Note that $params requires debuginfo.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/146736020674.27797.13488316780383460180.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-01 11:34:57 -03:00
Masami Hiramatsu
bc0622302f perf probe: Use cache entry if possible
Before analyzing debuginfo, try to find a corresponding entry from probe
cache always. This does not depend on --cache, the --cache enables to
store/update cache, but looking up the cache is always enabled.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/146736019226.27797.16366402884098398857.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-01 11:34:57 -03:00
Arnaldo Carvalho de Melo
10daf4d01b perf intlist: Rename for_each() macros to for_each_entry()
To match the semantics for list.h in the kernel, that are the
interface we use in them.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-mdp1heu9xjjc12zebh91232l@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-23 11:39:19 -03:00
Arnaldo Carvalho de Melo
602a1f4daa perf tools: Rename strlist_for_each() macros to for_each_entry()
To match the semantics for list.h in the kernel, that are the
interface we use in them.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-0b5i2ki9c3di6706fxpticsb@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-23 11:35:01 -03:00
Arnaldo Carvalho de Melo
32ca678dcd perf machine: Destructors should accept NULL
And do nothing, just like free(), to avoid having to test it in callers,
usually in error paths.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-q42gj3b3znhho9z1mrbo4jce@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-22 10:19:11 -03:00
Masami Hiramatsu
2fd457a345 perf probe: Add --cache option to cache the probe definitions
Add --cache option to cache the probe definitions. This just saves the
result of the dwarf analysis to probe cache.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20160615032840.31330.44412.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-15 14:34:42 -03:00
Masami Hiramatsu
c4ff49209b perf probe: Uncomment and export synthesize_perf_probe_point()
Uncomment and export synthesize_perf_probe_point() which had once
introduced but has been disabled for a long time. This renews the code
and re-enable it.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20160608092949.3116.21958.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-14 09:29:54 -03:00