Commit Graph

13 Commits

Author SHA1 Message Date
Linus Torvalds
9c5968db9e The various patchsets are summarized below. Plus of course many
indivudual patches which are described in their changelogs.
 
 - "Allocate and free frozen pages" from Matthew Wilcox reorganizes the
   page allocator so we end up with the ability to allocate and free
   zero-refcount pages.  So that callers (ie, slab) can avoid a refcount
   inc & dec.
 
 - "Support large folios for tmpfs" from Baolin Wang teaches tmpfs to use
   large folios other than PMD-sized ones.
 
 - "Fix mm/rodata_test" from Petr Tesarik performs some maintenance and
   fixes for this small built-in kernel selftest.
 
 - "mas_anode_descend() related cleanup" from Wei Yang tidies up part of
   the mapletree code.
 
 - "mm: fix format issues and param types" from Keren Sun implements a
   few minor code cleanups.
 
 - "simplify split calculation" from Wei Yang provides a few fixes and a
   test for the mapletree code.
 
 - "mm/vma: make more mmap logic userland testable" from Lorenzo Stoakes
   continues the work of moving vma-related code into the (relatively) new
   mm/vma.c.
 
 - "mm/page_alloc: gfp flags cleanups for alloc_contig_*()" from David
   Hildenbrand cleans up and rationalizes handling of gfp flags in the page
   allocator.
 
 - "readahead: Reintroduce fix for improper RA window sizing" from Jan
   Kara is a second attempt at fixing a readahead window sizing issue.  It
   should reduce the amount of unnecessary reading.
 
 - "synchronously scan and reclaim empty user PTE pages" from Qi Zheng
   addresses an issue where "huge" amounts of pte pagetables are
   accumulated
   (https://lore.kernel.org/lkml/cover.1718267194.git.zhengqi.arch@bytedance.com/).
   Qi's series addresses this windup by synchronously freeing PTE memory
   within the context of madvise(MADV_DONTNEED).
 
 - "selftest/mm: Remove warnings found by adding compiler flags" from
   Muhammad Usama Anjum fixes some build warnings in the selftests code
   when optional compiler warnings are enabled.
 
 - "mm: don't use __GFP_HARDWALL when migrating remote pages" from David
   Hildenbrand tightens the allocator's observance of __GFP_HARDWALL.
 
 - "pkeys kselftests improvements" from Kevin Brodsky implements various
   fixes and cleanups in the MM selftests code, mainly pertaining to the
   pkeys tests.
 
 - "mm/damon: add sample modules" from SeongJae Park enhances DAMON to
   estimate application working set size.
 
 - "memcg/hugetlb: Rework memcg hugetlb charging" from Joshua Hahn
   provides some cleanups to memcg's hugetlb charging logic.
 
 - "mm/swap_cgroup: remove global swap cgroup lock" from Kairui Song
   removes the global swap cgroup lock.  A speedup of 10% for a tmpfs-based
   kernel build was demonstrated.
 
 - "zram: split page type read/write handling" from Sergey Senozhatsky
   has several fixes and cleaups for zram in the area of zram_write_page().
   A watchdog softlockup warning was eliminated.
 
 - "move pagetable_*_dtor() to __tlb_remove_table()" from Kevin Brodsky
   cleans up the pagetable destructor implementations.  A rare
   use-after-free race is fixed.
 
 - "mm/debug: introduce and use VM_WARN_ON_VMG()" from Lorenzo Stoakes
   simplifies and cleans up the debugging code in the VMA merging logic.
 
 - "Account page tables at all levels" from Kevin Brodsky cleans up and
   regularizes the pagetable ctor/dtor handling.  This results in
   improvements in accounting accuracy.
 
 - "mm/damon: replace most damon_callback usages in sysfs with new core
   functions" from SeongJae Park cleans up and generalizes DAMON's sysfs
   file interface logic.
 
 - "mm/damon: enable page level properties based monitoring" from
   SeongJae Park increases the amount of information which is presented in
   response to DAMOS actions.
 
 - "mm/damon: remove DAMON debugfs interface" from SeongJae Park removes
   DAMON's long-deprecated debugfs interfaces.  Thus the migration to sysfs
   is completed.
 
 - "mm/hugetlb: Refactor hugetlb allocation resv accounting" from Peter
   Xu cleans up and generalizes the hugetlb reservation accounting.
 
 - "mm: alloc_pages_bulk: small API refactor" from Luiz Capitulino
   removes a never-used feature of the alloc_pages_bulk() interface.
 
 - "mm/damon: extend DAMOS filters for inclusion" from SeongJae Park
   extends DAMOS filters to support not only exclusion (rejecting), but
   also inclusion (allowing) behavior.
 
 - "Add zpdesc memory descriptor for zswap.zpool" from Alex Shi
   "introduces a new memory descriptor for zswap.zpool that currently
   overlaps with struct page for now.  This is part of the effort to reduce
   the size of struct page and to enable dynamic allocation of memory
   descriptors."
 
 - "mm, swap: rework of swap allocator locks" from Kairui Song redoes and
   simplifies the swap allocator locking.  A speedup of 400% was
   demonstrated for one workload.  As was a 35% reduction for kernel build
   time with swap-on-zram.
 
 - "mm: update mips to use do_mmap(), make mmap_region() internal" from
   Lorenzo Stoakes reworks MIPS's use of mmap_region() so that
   mmap_region() can be made MM-internal.
 
 - "mm/mglru: performance optimizations" from Yu Zhao fixes a few MGLRU
   regressions and otherwise improves MGLRU performance.
 
 - "Docs/mm/damon: add tuning guide and misc updates" from SeongJae Park
   updates DAMON documentation.
 
 - "Cleanup for memfd_create()" from Isaac Manjarres does that thing.
 
 - "mm: hugetlb+THP folio and migration cleanups" from David Hildenbrand
   provides various cleanups in the areas of hugetlb folios, THP folios and
   migration.
 
 - "Uncached buffered IO" from Jens Axboe implements the new
   RWF_DONTCACHE flag which provides synchronous dropbehind for pagecache
   reading and writing.  To permite userspace to address issues with
   massive buildup of useless pagecache when reading/writing fast devices.
 
 - "selftests/mm: virtual_address_range: Reduce memory" from Thomas
   Weißschuh fixes and optimizes some of the MM selftests.
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Merge tag 'mm-stable-2025-01-26-14-59' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:
 "The various patchsets are summarized below. Plus of course many
  indivudual patches which are described in their changelogs.

   - "Allocate and free frozen pages" from Matthew Wilcox reorganizes
     the page allocator so we end up with the ability to allocate and
     free zero-refcount pages. So that callers (ie, slab) can avoid a
     refcount inc & dec

   - "Support large folios for tmpfs" from Baolin Wang teaches tmpfs to
     use large folios other than PMD-sized ones

   - "Fix mm/rodata_test" from Petr Tesarik performs some maintenance
     and fixes for this small built-in kernel selftest

   - "mas_anode_descend() related cleanup" from Wei Yang tidies up part
     of the mapletree code

   - "mm: fix format issues and param types" from Keren Sun implements a
     few minor code cleanups

   - "simplify split calculation" from Wei Yang provides a few fixes and
     a test for the mapletree code

   - "mm/vma: make more mmap logic userland testable" from Lorenzo
     Stoakes continues the work of moving vma-related code into the
     (relatively) new mm/vma.c

   - "mm/page_alloc: gfp flags cleanups for alloc_contig_*()" from David
     Hildenbrand cleans up and rationalizes handling of gfp flags in the
     page allocator

   - "readahead: Reintroduce fix for improper RA window sizing" from Jan
     Kara is a second attempt at fixing a readahead window sizing issue.
     It should reduce the amount of unnecessary reading

   - "synchronously scan and reclaim empty user PTE pages" from Qi Zheng
     addresses an issue where "huge" amounts of pte pagetables are
     accumulated:

       https://lore.kernel.org/lkml/cover.1718267194.git.zhengqi.arch@bytedance.com/

     Qi's series addresses this windup by synchronously freeing PTE
     memory within the context of madvise(MADV_DONTNEED)

   - "selftest/mm: Remove warnings found by adding compiler flags" from
     Muhammad Usama Anjum fixes some build warnings in the selftests
     code when optional compiler warnings are enabled

   - "mm: don't use __GFP_HARDWALL when migrating remote pages" from
     David Hildenbrand tightens the allocator's observance of
     __GFP_HARDWALL

   - "pkeys kselftests improvements" from Kevin Brodsky implements
     various fixes and cleanups in the MM selftests code, mainly
     pertaining to the pkeys tests

   - "mm/damon: add sample modules" from SeongJae Park enhances DAMON to
     estimate application working set size

   - "memcg/hugetlb: Rework memcg hugetlb charging" from Joshua Hahn
     provides some cleanups to memcg's hugetlb charging logic

   - "mm/swap_cgroup: remove global swap cgroup lock" from Kairui Song
     removes the global swap cgroup lock. A speedup of 10% for a
     tmpfs-based kernel build was demonstrated

   - "zram: split page type read/write handling" from Sergey Senozhatsky
     has several fixes and cleaups for zram in the area of
     zram_write_page(). A watchdog softlockup warning was eliminated

   - "move pagetable_*_dtor() to __tlb_remove_table()" from Kevin
     Brodsky cleans up the pagetable destructor implementations. A rare
     use-after-free race is fixed

   - "mm/debug: introduce and use VM_WARN_ON_VMG()" from Lorenzo Stoakes
     simplifies and cleans up the debugging code in the VMA merging
     logic

   - "Account page tables at all levels" from Kevin Brodsky cleans up
     and regularizes the pagetable ctor/dtor handling. This results in
     improvements in accounting accuracy

   - "mm/damon: replace most damon_callback usages in sysfs with new
     core functions" from SeongJae Park cleans up and generalizes
     DAMON's sysfs file interface logic

   - "mm/damon: enable page level properties based monitoring" from
     SeongJae Park increases the amount of information which is
     presented in response to DAMOS actions

   - "mm/damon: remove DAMON debugfs interface" from SeongJae Park
     removes DAMON's long-deprecated debugfs interfaces. Thus the
     migration to sysfs is completed

   - "mm/hugetlb: Refactor hugetlb allocation resv accounting" from
     Peter Xu cleans up and generalizes the hugetlb reservation
     accounting

   - "mm: alloc_pages_bulk: small API refactor" from Luiz Capitulino
     removes a never-used feature of the alloc_pages_bulk() interface

   - "mm/damon: extend DAMOS filters for inclusion" from SeongJae Park
     extends DAMOS filters to support not only exclusion (rejecting),
     but also inclusion (allowing) behavior

   - "Add zpdesc memory descriptor for zswap.zpool" from Alex Shi
     introduces a new memory descriptor for zswap.zpool that currently
     overlaps with struct page for now. This is part of the effort to
     reduce the size of struct page and to enable dynamic allocation of
     memory descriptors

   - "mm, swap: rework of swap allocator locks" from Kairui Song redoes
     and simplifies the swap allocator locking. A speedup of 400% was
     demonstrated for one workload. As was a 35% reduction for kernel
     build time with swap-on-zram

   - "mm: update mips to use do_mmap(), make mmap_region() internal"
     from Lorenzo Stoakes reworks MIPS's use of mmap_region() so that
     mmap_region() can be made MM-internal

   - "mm/mglru: performance optimizations" from Yu Zhao fixes a few
     MGLRU regressions and otherwise improves MGLRU performance

   - "Docs/mm/damon: add tuning guide and misc updates" from SeongJae
     Park updates DAMON documentation

   - "Cleanup for memfd_create()" from Isaac Manjarres does that thing

   - "mm: hugetlb+THP folio and migration cleanups" from David
     Hildenbrand provides various cleanups in the areas of hugetlb
     folios, THP folios and migration

   - "Uncached buffered IO" from Jens Axboe implements the new
     RWF_DONTCACHE flag which provides synchronous dropbehind for
     pagecache reading and writing. To permite userspace to address
     issues with massive buildup of useless pagecache when
     reading/writing fast devices

   - "selftests/mm: virtual_address_range: Reduce memory" from Thomas
     Weißschuh fixes and optimizes some of the MM selftests"

* tag 'mm-stable-2025-01-26-14-59' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits)
  mm/compaction: fix UBSAN shift-out-of-bounds warning
  s390/mm: add missing ctor/dtor on page table upgrade
  kasan: sw_tags: use str_on_off() helper in kasan_init_sw_tags()
  tools: add VM_WARN_ON_VMG definition
  mm/damon/core: use str_high_low() helper in damos_wmark_wait_us()
  seqlock: add missing parameter documentation for raw_seqcount_try_begin()
  mm/page-writeback: consolidate wb_thresh bumping logic into __wb_calc_thresh
  mm/page_alloc: remove the incorrect and misleading comment
  zram: remove zcomp_stream_put() from write_incompressible_page()
  mm: separate move/undo parts from migrate_pages_batch()
  mm/kfence: use str_write_read() helper in get_access_type()
  selftests/mm/mkdirty: fix memory leak in test_uffdio_copy()
  kasan: hw_tags: Use str_on_off() helper in kasan_init_hw_tags()
  selftests/mm: virtual_address_range: avoid reading from VM_IO mappings
  selftests/mm: vm_util: split up /proc/self/smaps parsing
  selftests/mm: virtual_address_range: unmap chunks after validation
  selftests/mm: virtual_address_range: mmap() without PROT_WRITE
  selftests/memfd/memfd_test: fix possible NULL pointer dereference
  mm: add FGP_DONTCACHE folio creation flag
  mm: call filemap_fdatawrite_range_kick() after IOCB_DONTCACHE issue
  ...
2025-01-26 18:36:23 -08:00
Luiz Capitulino
6bf9b5b40a mm: alloc_pages_bulk: rename API
The previous commit removed the page_list argument from
alloc_pages_bulk_noprof() along with the alloc_pages_bulk_list() function.

Now that only the *_array() flavour of the API remains, we can do the
following renaming (along with the _noprof() ones):

  alloc_pages_bulk_array -> alloc_pages_bulk
  alloc_pages_bulk_array_mempolicy -> alloc_pages_bulk_mempolicy
  alloc_pages_bulk_array_node -> alloc_pages_bulk_node

Link: https://lkml.kernel.org/r/275a3bbc0be20fbe9002297d60045e67ab3d4ada.1734991165.git.luizcap@redhat.com
Signed-off-by: Luiz Capitulino <luizcap@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-01-25 20:22:31 -08:00
Chen Linxuan
41fb0fabc4 erofs: return SHRINK_EMPTY if no objects to free
Comments in file include/linux/shrinker.h says that
`count_objects` of `struct shrinker` should return SHRINK_EMPTY
when there are no objects to free.

> If there are no objects to free, it should return SHRINK_EMPTY,
> while 0 is returned in cases of the number of freeable items cannot
> be determined or shrinker should skip this cache for this time
> (e.g., their number is below shrinkable limit).

Signed-off-by: Chen Linxuan <chenlinxuan@uniontech.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/149E6E64B5B6B5E8+20250116083303.199817-1-chenlinxuan@uniontech.com
[ Gao Xiang: should have no impact since it's not memcg-aware. ]
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2025-01-17 03:24:30 +08:00
Gao Xiang
b10a1e5643 erofs: fix rare pcluster memory leak after unmounting
There may still exist some pcluster with valid reference counts
during unmounting.  Instead of introducing another synchronization
primitive, just try again as unmounting is relatively rare.  This
approach is similar to z_erofs_cache_invalidate_folio().

It was also reported by syzbot as a UAF due to commit f5ad9f9a60
("erofs: free pclusters if no cached folio is attached"):

BUG: KASAN: slab-use-after-free in do_raw_spin_trylock+0x72/0x1f0 kernel/locking/spinlock_debug.c:123
..
 queued_spin_trylock include/asm-generic/qspinlock.h:92 [inline]
 do_raw_spin_trylock+0x72/0x1f0 kernel/locking/spinlock_debug.c:123
 __raw_spin_trylock include/linux/spinlock_api_smp.h:89 [inline]
 _raw_spin_trylock+0x20/0x80 kernel/locking/spinlock.c:138
 spin_trylock include/linux/spinlock.h:361 [inline]
 z_erofs_put_pcluster fs/erofs/zdata.c:959 [inline]
 z_erofs_decompress_pcluster fs/erofs/zdata.c:1403 [inline]
 z_erofs_decompress_queue+0x3798/0x3ef0 fs/erofs/zdata.c:1425
 z_erofs_decompressqueue_work+0x99/0xe0 fs/erofs/zdata.c:1437
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa68/0x1840 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f2/0x390 kernel/kthread.c:389
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

However, it seems a long outstanding memory leak.  Fix it now.

Fixes: f5ad9f9a60 ("erofs: free pclusters if no cached folio is attached")
Reported-by: syzbot+7ff87b095e7ca0c5ac39@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/r/674c1235.050a0220.ad585.0032.GAE@google.com
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241203072821.1885740-1-hsiangkao@linux.alibaba.com
2024-12-13 00:24:12 +08:00
Gao Xiang
9c91f95962 erofs: move erofs_workgroup operations into zdata.c
Move related helpers into zdata.c as an intermediate step of getting
rid of `struct erofs_workgroup`, and rename:

 erofs_workgroup_put => z_erofs_put_pcluster
 erofs_workgroup_get => z_erofs_get_pcluster
 erofs_try_to_release_workgroup => erofs_try_to_release_pcluster
 erofs_shrink_workstation => z_erofs_shrink_scan

Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241021035323.3280682-2-hsiangkao@linux.alibaba.com
2024-11-18 18:50:12 +08:00
Gao Xiang
b091e8ed24 erofs: get rid of erofs_{find,insert}_workgroup
Just fold them into the only two callers since
they are simple enough.

Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241021035323.3280682-1-hsiangkao@linux.alibaba.com
2024-11-18 18:50:03 +08:00
Gao Xiang
0005e01e1e erofs: fix out-of-bound access when z_erofs_gbuf_growsize() partially fails
If z_erofs_gbuf_growsize() partially fails on a global buffer due to
memory allocation failure or fault injection (as reported by syzbot [1]),
new pages need to be freed by comparing to the existing pages to avoid
memory leaks.

However, the old gbuf->pages[] array may not be large enough, which can
lead to null-ptr-deref or out-of-bound access.

Fix this by checking against gbuf->nrpages in advance.

[1] https://lore.kernel.org/r/000000000000f7b96e062018c6e3@google.com

Reported-by: syzbot+242ee56aaa9585553766@syzkaller.appspotmail.com
Fixes: d6db47e571 ("erofs: do not use pagepool in z_erofs_gbuf_growsize()")
Cc: <stable@vger.kernel.org> # 6.10+
Reviewed-by: Chunhai Guo <guochunhai@vivo.com>
Reviewed-by: Sandeep Dhavale <dhavale@google.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240820085619.1375963-1-hsiangkao@linux.alibaba.com
2024-08-21 08:12:05 +08:00
Gao Xiang
7dc5537c3f erofs: fix race in z_erofs_get_gbuf()
In z_erofs_get_gbuf(), the current task may be migrated to another
CPU between `z_erofs_gbuf_id()` and `spin_lock(&gbuf->lock)`.

Therefore, z_erofs_put_gbuf() will trigger the following issue
which was found by stress test:

<2>[772156.434168] kernel BUG at fs/erofs/zutil.c:58!
..
<4>[772156.435007]
<4>[772156.439237] CPU: 0 PID: 3078 Comm: stress Kdump: loaded Tainted: G            E      6.10.0-rc7+ #2
<4>[772156.439239] Hardware name: Alibaba Cloud Alibaba Cloud ECS, BIOS 1.0.0 01/01/2017
<4>[772156.439241] pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
<4>[772156.439243] pc : z_erofs_put_gbuf+0x64/0x70 [erofs]
<4>[772156.439252] lr : z_erofs_lz4_decompress+0x600/0x6a0 [erofs]
..
<6>[772156.445958] stress (3127): drop_caches: 1
<4>[772156.446120] Call trace:
<4>[772156.446121]  z_erofs_put_gbuf+0x64/0x70 [erofs]
<4>[772156.446761]  z_erofs_lz4_decompress+0x600/0x6a0 [erofs]
<4>[772156.446897]  z_erofs_decompress_queue+0x740/0xa10 [erofs]
<4>[772156.447036]  z_erofs_runqueue+0x428/0x8c0 [erofs]
<4>[772156.447160]  z_erofs_readahead+0x224/0x390 [erofs]
..

Fixes: f36f3010f6 ("erofs: rename per-CPU buffers to global buffer pool and make it configurable")
Cc: <stable@vger.kernel.org> # 6.10+
Reviewed-by: Chunhai Guo <guochunhai@vivo.com>
Reviewed-by: Sandeep Dhavale <dhavale@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240722035110.3456740-1-hsiangkao@linux.alibaba.com
2024-07-26 18:47:33 +08:00
Sandeep Dhavale
9d01f6f6d8 erofs: fix possible memory leak in z_erofs_gbuf_exit()
Because we incorrectly reused of variable `i` in `z_erofs_gbuf_exit()`
for inner loop, we may exit early from outer loop resulting in memory
leak. Fix this by using separate variable for iterating through inner loop.

Fixes: f36f3010f6 ("erofs: rename per-CPU buffers to global buffer pool and make it configurable")
Signed-off-by: Sandeep Dhavale <dhavale@google.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20240624220206.3373197-1-dhavale@google.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2024-06-26 17:02:15 +08:00
Chunhai Guo
0f6273ab46 erofs: add a reserved buffer pool for lz4 decompression
This adds a special global buffer pool (in the end) for reserved pages.

Using a reserved pool for LZ4 decompression significantly reduces the
time spent on extra temporary page allocation for the extreme cases in
low memory scenarios.

The table below shows the reduction in time spent on page allocation for
LZ4 decompression when using a reserved pool. The results were obtained
from multi-app launch benchmarks on ARM64 Android devices running the
5.15 kernel with an 8-core CPU and 8GB of memory. In the benchmark, we
launched 16 frequently-used apps, and the camera app was the last one in
each round. The data in the table is the average time of camera app for
each round.

After using the reserved pool, there was an average improvement of 150ms
in the overall launch time of our camera app, which was obtained from
the systrace log.

+--------------+---------------+--------------+---------+
|              | w/o page pool | w/ page pool |  diff   |
+--------------+---------------+--------------+---------+
| Average (ms) |     3434      |      21      | -99.38% |
+--------------+---------------+--------------+---------+

Based on the benchmark logs, 64 pages are sufficient for 95% of
scenarios. This value can be adjusted with a module parameter
`reserved_pages`. The default value is 0.

This pool is currently only used for the LZ4 decompressor, but it can be
applied to more decompressors if needed.

Signed-off-by: Chunhai Guo <guochunhai@vivo.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240402131523.2703948-1-guochunhai@vivo.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2024-05-08 17:12:51 +08:00
Chunhai Guo
d6db47e571 erofs: do not use pagepool in z_erofs_gbuf_growsize()
Let's use alloc_pages_bulk_array() for simplicity and get rid of
unnecessary pagepool.

Signed-off-by: Chunhai Guo <guochunhai@vivo.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240402092757.2635257-1-guochunhai@vivo.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2024-05-08 17:12:50 +08:00
Chunhai Guo
f36f3010f6 erofs: rename per-CPU buffers to global buffer pool and make it configurable
It will cost more time if compressed buffers are allocated on demand for
low-latency algorithms (like lz4) so EROFS uses per-CPU buffers to keep
compressed data if in-place decompression is unfulfilled.  While it is kind
of wasteful of memory for a device with hundreds of CPUs, and only a small
number of CPUs concurrently decompress most of the time.

This patch renames it as 'global buffer pool' and makes it configurable.
This allows two or more CPUs to share a common buffer to reduce memory
occupation.

Suggested-by: Gao Xiang <xiang@kernel.org>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: Chunhai Guo <guochunhai@vivo.com>
Link: https://lore.kernel.org/r/20240402100036.2673604-1-guochunhai@vivo.com
Signed-off-by: Sandeep Dhavale <dhavale@google.com>
Link: https://lore.kernel.org/r/20240408215231.3376659-1-dhavale@google.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2024-05-08 17:12:49 +08:00
Chunhai Guo
cacd5b04e2 erofs: rename utils.c to zutil.c
Currently, utils.c is only useful if CONFIG_EROFS_FS_ZIP is on.
So let's rename it to zutil.c as well as avoid its inclusion if
CONFIG_EROFS_FS_ZIP is explicitly disabled.

Signed-off-by: Chunhai Guo <guochunhai@vivo.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240401135550.2550043-1-guochunhai@vivo.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2024-05-08 17:12:49 +08:00