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perf doc: Document new IBS capabilities in man page

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Include examples of:

o Privilege filter with Fetch and Op PMUs, including swfilt approach on
  Zen5 and older platforms and hardware assisted filter on Zen6 and newer
  platforms

o Streaming store filter with Op PMU

o Fetch latency filter with Fetch PMU

Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ananth Narayan <ananth.narayan@amd.com>
Cc: Dapeng Mi <dapeng1.mi@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Manali Shukla <manali.shukla@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Santosh Shukla <santosh.shukla@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Ravi Bangoria 2026-05-08 06:00:04 +00:00 committed by Arnaldo Carvalho de Melo
parent 873f232d09
commit a31423e67c
1 changed files with 39 additions and 0 deletions
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39
tools/perf/Documentation/perf-amd-ibs.txt
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@ -69,6 +69,14 @@ Per-cpu profile (cpu10), cycles event, sampling period: 100000
# perf record -e ibs_op// -c 100000 -C 10
Userspace only, per-cpu profile (cpu10), cycles event, sampling period: 100000
Zen6 onward (See NOTES):
# perf record -e ibs_op//u -c 100000 -C 10
Until Zen5:
# perf record -e ibs_op/swfilt=1/u -c 100000 -C 10
Per-cpu profile (cpu10), cycles event, sampling freq: 1000
# perf record -e ibs_op// -F 1000 -C 10
@ -94,6 +102,11 @@ onward)
Latency value which is a multiple of 128 incurs a little less profiling
overhead compared to other values.
System-wide profile, cycles event, sampling period: 100000, streaming store
filter (Zen6 onward)
# perf record -e ibs_op/strmst=1/ -c 100000 -a
Per process(upstream v6.2 onward), uOps event, sampling period: 100000
# perf record -e ibs_op/cnt_ctl=1/ -c 100000 -p 1234
@ -150,6 +163,14 @@ System-wide profile, fetch ops event, sampling period: 100000
# perf record -e ibs_fetch// -c 100000 -a
Userspace only, system-wide profile, fetch ops event, sampling period: 100000
Zen6 onward (See NOTES):
# perf record -e ibs_fetch//u -c 100000 -a
Until Zen5:
# perf record -e ibs_fetch/swfilt=1/u -c 100000 -a
System-wide profile, fetch ops event, sampling period: 100000, Random enable
# perf record -e ibs_fetch/rand_en=1/ -c 100000 -a
@ -158,6 +179,15 @@ System-wide profile, fetch ops event, sampling period: 100000, Random enable
helps in cases like long running loops where PMU is tagging the same
instruction over and over because of fixed sample period.
System-wide profile, fetch ops event, sampling period: 10000, fetch latency
filter (Zen6 onward)
# perf record -e ibs_fetch/fetchlat=128/ -c 10000 -a
Supported fetch latency threshold values are 128 to 1920 (both inclusive).
Latency value which is a multiple of 128 incurs a little less profiling
overhead compared to other values.
etc.
PERF MEM AND PERF C2C
@ -216,6 +246,15 @@ sort keys. For example:
Please refer to their man page for more detail.
NOTES
-----
Hardware privilege filtering uses bit 63 to distinguish between kernel
and userspace addresses. Hardware privilege filtering is not supported
on 32-bit systems. Also, the bit 63 convention is not universal and can
fail in specific environments, such as, using 64-bit host IBS to profile
a 32-bit guest, using 64-bit host IBS to profile non-Linux 64-bit guests
that do not adhere to the bit 63 privilege standard etc.
SEE ALSO
--------