linux.git/tools/perf/util/parse-events.c, branch for-next

perf tools: Do not set exclude_guest for precise_ip

2024-10-22T16:52:11+00:00

It seems perf sets the exclude_guest bit because of Intel PEBS
implementation which uses a virtual address.  IIUC now kernel disables
PEBS when it goes to the guest mode regardless of this bit so we don't
need to set it explicitly.  At least for the other archs/vendors.

I found the commit 1342798cc13e set the exclude_guest for precise_ip
in the tool and the commit 20b279ddb38c added kernel side enforcement
which was reverted by commit a706d965dcfd later.

Actually it doesn't set the exclude_guest for the default event
(cycles:P) already.

  $ grep -m1 vendor /proc/cpuinfo
  vendor_id	: GenuineIntel

  $ perf record -e cycles:P true
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.002 MB perf.data (9 samples) ]

  $ perf evlist -v | tr ',' '\n' | grep -e exclude -e precise
   precise_ip: 3

But having lower 'p' modifier set the bit for some reason.

  $ perf record -e cycles:pp true
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.002 MB perf.data (9 samples) ]

  $ perf evlist -v | tr ',' '\n' | grep -e exclude -e precise
   precise_ip: 2
   exclude_guest: 1

Actually AMD IBS suffers from this because it doesn't support excludes
and having this bit effectively disables new features in the current
implementation (due to the missing feature check).

  $ grep -m1 vendor /proc/cpuinfo
  vendor_id	: AuthenticAMD

  $ perf record -W -e cycles:p -vv true 2>&1 | grep switching
  switching off PERF_FORMAT_LOST support
  switching off weight struct support
  switching off bpf_event
  switching off ksymbol
  switching off cloexec flag
  switching off mmap2
  switching off exclude_guest, exclude_host

By not setting exclude_guest, we can fix this inconsistency and the
troubles.

Reviewed-by: Ian Rogers 
Reviewed-by: James Clark 
Reviewed-by: Ravi Bangoria 
Acked-by: Kan Liang 
Cc: James Clark 
Cc: Atish Patra 
Cc: Mingwei Zhang 
Cc: Kajol Jain 
Cc: Thomas Richter 
Cc: Palmer Dabbelt 
Link: https://lore.kernel.org/r/20241016062359.264929-5-namhyung@kernel.org
Signed-off-by: Namhyung Kim

perf tools: Don't set attr.exclude_guest by default

2024-10-22T16:52:11+00:00

The exclude_guest in the event attribute is to limit profiling in the
host environment.  But I'm not sure why we want to set it by default
cause we don't care about it in most cases and I feel like it just
makes new PMU implementation complicated.

Of course it's useful for perf kvm command so I added the
exclude_GH_default variable to preserve the old behavior for perf kvm
and other commands like perf record and stat won't set the exclude bit.
This is helpful for AMD IBS case since having exclude_guest bit will
clear new feature bit due to the missing feature check logic.

  $ sysctl kernel.perf_event_paranoid
  kernel.perf_event_paranoid = 0

  $ perf record -W -e ibs_op// -vv true 2>&1 | grep switching
  switching off PERF_FORMAT_LOST support
  switching off weight struct support
  switching off bpf_event
  switching off ksymbol
  switching off cloexec flag
  switching off mmap2
  switching off exclude_guest, exclude_host

Intestingly, I found it sets the exclude_bit if "u" modifier is used.
I don't know why but it's neither intuitive nor consistent.  Let's
remove the bit there too.

Reviewed-by: Ian Rogers 
Reviewed-by: James Clark 
Reviewed-by: Ravi Bangoria 
Acked-by: Kan Liang 
Cc: James Clark 
Cc: Atish Patra 
Cc: Mingwei Zhang 
Cc: Kajol Jain 
Cc: Thomas Richter 
Cc: Palmer Dabbelt 
Link: https://lore.kernel.org/r/20241016062359.264929-3-namhyung@kernel.org
Signed-off-by: Namhyung Kim

perf tool_pmu: Factor tool events into their own PMU

2024-10-11T06:40:32+00:00

Rather than treat tool events as a special kind of event, create a
tool only PMU where the events/aliases match the existing
duration_time, user_time and system_time events. Remove special
parsing and printing support for the tool events, but add function
calls for when PMU functions are called on a tool_pmu.

Move the tool PMU code in evsel into tool_pmu.c to better encapsulate
the tool event behavior in that file.

Signed-off-by: Ian Rogers 
Acked-by: Namhyung Kim 
Link: https://lore.kernel.org/r/20241002032016.333748-5-irogers@google.com
Signed-off-by: Namhyung Kim

perf parse-events: Expose/rename config_term_name

2024-10-11T06:40:32+00:00

Expose config_term_name as parse_events__term_type_str so that PMUs not
in pmu.c may access it.

Signed-off-by: Ian Rogers 
Acked-by: Namhyung Kim 
Link: https://lore.kernel.org/r/20241002032016.333748-4-irogers@google.com
Signed-off-by: Namhyung Kim

perf pmu: Allow hardcoded terms to be applied to attributes

2024-10-11T06:40:32+00:00

Hard coded terms like "config=10" are skipped by perf_pmu__config
assuming they were already applied to a perf_event_attr by parse
event's config_attr function. When doing a reverse number to name
lookup in perf_pmu__name_from_config, as the hardcoded terms aren't
applied the config value is incorrect leading to misses or false
matches. Fix this by adding a parameter to have perf_pmu__config apply
hardcoded terms too (not just in parse event's config_term_common).

Signed-off-by: Ian Rogers 
Acked-by: Namhyung Kim 
Link: https://lore.kernel.org/r/20241002032016.333748-3-irogers@google.com
Signed-off-by: Namhyung Kim

perf evsel: Remove pmu_name

2024-09-26T20:26:11+00:00

"evsel->pmu_name" is only ever assigned a strdup of "pmu->name", a
strdup of "evsel->pmu_name" or NULL. As such, prefer to use
"pmu->name" directly and even to directly compare PMUs than PMU
names. For safety, add some additional NULL tests.

Acked-by: Namhyung Kim 
Signed-off-by: Ian Rogers 
[ Fix arm-spe.c usage of pmu_name and empty PMU name ]
Acked-by: Kan Liang 
Signed-off-by: James Clark 
Cc: Yang Jihong 
Cc: Dominique Martinet 
Cc: Howard Chu 
Cc: Ze Gao 
Cc: Yicong Yang 
Cc: Weilin Wang 
Cc: Will Deacon 
Cc: Mike Leach 
Cc: Jing Zhang 
Cc: Yang Li 
Cc: Leo Yan 
Cc: ak@linux.intel.com
Cc: Athira Rajeev 
Cc: linux-arm-kernel@lists.infradead.org
Cc: Sun Haiyong 
Cc: John Garry 
Link: https://lore.kernel.org/r/20240926144851.245903-6-james.clark@linaro.org
Signed-off-by: Namhyung Kim

perf evsel: Add alternate_hw_config and use in evsel__match

2024-09-26T20:26:11+00:00

There are cases where we want to match events like instructions and
cycles with legacy hardware values, in particular in stat-shadow's
hard coded metrics. An evsel's name isn't a good point of reference as
it gets altered, strstr would be too imprecise and re-parsing the
event from its name is silly. Instead, hold the legacy hardware event
name, determined during parsing, in the evsel for this matching case.

Inline evsel__match2 that is only used in builtin-diff.

Acked-by: Namhyung Kim 
Signed-off-by: Ian Rogers 
Acked-by: Kan Liang 
Signed-off-by: James Clark 
Cc: Yang Jihong 
Cc: Dominique Martinet 
Cc: Colin Ian King 
Cc: Howard Chu 
Cc: Yunseong Kim 
Cc: Ze Gao 
Cc: Yicong Yang 
Cc: Weilin Wang 
Cc: Will Deacon 
Cc: Mike Leach 
Cc: Jing Zhang 
Cc: Yang Li 
Cc: Leo Yan 
Cc: ak@linux.intel.com
Cc: Athira Rajeev 
Cc: linux-arm-kernel@lists.infradead.org
Cc: Sun Haiyong 
Cc: John Garry 
Link: https://lore.kernel.org/r/20240926144851.245903-2-james.clark@linaro.org
Signed-off-by: Namhyung Kim

perf pmus: Fake PMU clean up

2024-09-11T14:27:42+00:00

Rather than passing a fake PMU around, just pass that the fake PMU
should be used - true when doing testing. Move the fake PMU into
pmus.[ch] and try to abstract the PMU's properties in pmu.c, ie so
there is less "if fake_pmu" in non-PMU code. Give the fake PMU a made
up type number.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Athira Rajeev 
Cc: Benjamin Gray 
Cc: Changbin Du 
Cc: Clément Le Goffic 
Cc: Colin Ian King 
Cc: Dominique Martinet 
Cc: Dr. David Alan Gilbert 
Cc: Howard Chu 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jing Zhang 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Junhao He 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Mike Leach 
Cc: Namhyung Kim 
Cc: Oliver Upton 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Sandipan Das 
Cc: Sun Haiyong 
Cc: Tiezhu Yang 
Cc: Veronika Molnarova 
Cc: Weilin Wang 
Cc: Will Deacon 
Cc: Xu Yang 
Cc: Yang Jihong 
Cc: Yicong Yang 
Cc: Ze Gao 
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20240907050830.6752-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf parse-events: Vary default_breakpoint_len on i386 and arm64

2024-09-04T12:50:46+00:00

On arm64 the breakpoint length should be 4-bytes but 8-bytes is
tolerated as perf passes that as sizeof(long). Just pass the correct
value.

On i386 the sizeof(long) check in the kernel needs to match the
kernel's long size. Check using an environment (uname checks) whether
4 or 8 bytes needs to be passed. Cache the value in a static.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Athira Rajeev 
Cc: Chaitanya S Prakash 
Cc: Colin Ian King 
Cc: Dominique Martinet 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Junhao He 
Cc: Kan Liang 
Cc: Mark Rutland 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Yang Jihong 
Link: https://lore.kernel.org/r/20240904050606.752788-6-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf parse-events: Add default_breakpoint_len helper

2024-09-04T12:49:09+00:00

The default breakpoint length is "sizeof(long)" however this is
incorrect on platforms like Aarch64 where sizeof(long) is 8 but the
breakpoint length is 4. Add a helper function that can be used to
determine the correct breakpoint length, in this change it just
returns the existing default sizeof(long) value.

Use the helper in the bp_account test so that, when modifying the
event from a watchpoint to a breakpoint, the breakpoint length is
appropriate for the architecture and not just sizeof(long).

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Athira Rajeev 
Cc: Chaitanya S Prakash 
Cc: Colin Ian King 
Cc: Dominique Martinet 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Junhao He 
Cc: Kan Liang 
Cc: Mark Rutland 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Yang Jihong 
Link: https://lore.kernel.org/r/20240904050606.752788-5-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo