When displaying sizes of various sorts, tc commonly uses the function
sprint_size() to format the size into a buffer as a human-readable string.
This string is then displayed either using print_string(), or in some code
even fprintf(). As a result, a typical sequence of code when formatting a
size is something like the following:
SPRINT_BUF(b);
print_uint(PRINT_JSON, "foo", NULL, foo);
print_string(PRINT_FP, NULL, "foo %s ", sprint_size(foo, b));
For a concept as broadly useful as size, it would be better to have a
dedicated function in json_print.
To that end, move sprint_size() from tc_util to json_print. Add helpers
print_size() and print_color_size() that wrap arount sprint_size() and
provide the JSON dispatch as appropriate.
Since print_size() should be the preferred interface, convert vast majority
of uses of sprint_size() to print_size(). Two notable exceptions are:
- q_tbf, which does not show the size as such, but uses the string
"$human_readable_size/$cell_size" even in JSON. There is simply no way to
have print_size() emit the same text, because print_size() in JSON mode
should of course just use the raw number, without human-readable frills.
- q_cake, which relies on the existence of sprint_size() in its macro-based
formatting helpers. There might be ways to convert this particular case,
but given q_tbf simply cannot be converted, leave it as is.
Signed-off-by: Petr Machata <me@pmachata.org>
Signed-off-by: David Ahern <dsahern@gmail.com>
Enable proper JSON output for the SFQ Qdisc.
Use the long double format specifier to print the value of
"probability".
Also, fix the indentation in the online output of the contents in the
tc_sfqred_stats structure.
Signed-off-by: Leslie Monis <lesliemonis@gmail.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Every tool in the iproute2 package have one or more function to show
an help message to the user. Some of these functions print the help
line by line with a series of printf call, e.g. ip/xfrm_state.c does
60 fprintf calls.
If we group all the calls to a single one and just concatenate strings,
we save a lot of libc calls and thus object size. The size difference
of the compiled binaries calculated with bloat-o-meter is:
ip/ip:
add/remove: 0/0 grow/shrink: 5/15 up/down: 103/-4796 (-4693)
Total: Before=672591, After=667898, chg -0.70%
ip/rtmon:
add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-54 (-54)
Total: Before=48879, After=48825, chg -0.11%
tc/tc:
add/remove: 0/2 grow/shrink: 31/10 up/down: 882/-6133 (-5251)
Total: Before=351912, After=346661, chg -1.49%
bridge/bridge:
add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-459 (-459)
Total: Before=70502, After=70043, chg -0.65%
misc/lnstat:
add/remove: 0/1 grow/shrink: 1/0 up/down: 48/-486 (-438)
Total: Before=9960, After=9522, chg -4.40%
tipc/tipc:
add/remove: 0/0 grow/shrink: 1/1 up/down: 18/-62 (-44)
Total: Before=79182, After=79138, chg -0.06%
While at it, indent some strings which were starting at column 0,
and use tabs where possible, to have a consistent style across helps.
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Number of qdiscs use the same set of flags to control shared RED
implementation. Add a helper for printing those flags.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
This patch adapts the tc command line interface to allow bandwidth limits
to be specified as a percentage of the interface's capacity.
Adding this functionality requires passing the specified device string to
each class/qdisc which changes the prototype for a couple of functions: the
.parse_qopt and .parse_copt interfaces. The device string is a required
parameter for tc-qdisc and tc-class, and when not specified, the kernel
returns ENODEV. In this patch, if the user tries to specify a bandwidth
percentage without naming the device, we return an error from userspace.
Signed-off-by: Nishanth Devarajan<ndev2021@gmail.com>
This big patch was compiled by vimgrepping for memset calls and changing
to C99 initializer if applicable. One notable exception is the
initialization of union bpf_attr in tc/tc_bpf.c: changing it would break
for older gcc versions (at least <=3.4.6).
Calls to memset for struct rtattr pointer fields for parse_rtattr*()
were just dropped since they are not needed.
The changes here allowed the compiler to discover some unused variables,
so get rid of them, too.
Signed-off-by: Phil Sutter <phil@nwl.cc>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Adds an optional Random Early Detection on each SFQ flow queue.
Traditional SFQ limits count of packets, while RED permits to also
control number of bytes per flow, and adds ECN capability as well.
1) We dont handle the idle time management in this RED implementation,
since each 'new flow' begins with a null qavg. We really want to address
backlogged flows.
2) if headdrop is selected, we try to ecn mark first packet instead of
currently enqueued packet. This gives faster feedback for tcp flows
compared to traditional RED [ marking the last packet in queue ]
Example of use :
tc qdisc add dev $DEV parent 1:1 handle 10: est 1sec 4sec sfq \
limit 3000 headdrop flows 512 divisor 16384 \
redflowlimit 100000 min 8000 max 60000 probability 0.20 ecn
qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop
flows 512/16384 divisor 16384
ewma 6 min 8000b max 60000b probability 0.2 ecn
prob_mark 0 prob_mark_head 4876 prob_drop 6131
forced_mark 0 forced_mark_head 0 forced_drop 0
Sent 1175211782 bytes 777537 pkt (dropped 6131, overlimits 11007
requeues 0)
rate 99483Kbit 8219pps backlog 689392b 456p requeues 0
In this test, with 64 netperf TCP_STREAM sessions, 50% using ECN enabled
flows, we can see number of packets CE marked is smaller than number of
drops (for non ECN flows)
If same test is run, without RED, we can check backlog is much bigger.
qdisc sfq 10: parent 1:1 limit 3000p quantum 1514b depth 127 headdrop
flows 512/16384 divisor 16384
Sent 1148683617 bytes 795006 pkt (dropped 0, overlimits 0 requeues 0)
rate 98429Kbit 8521pps backlog 1221290b 841p requeues 0
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
