The perf tools annotation code used for a long time parsing the output
of binutils's objdump (or its reimplementations, like llvm's) to then
parse and augment it with samples, allow navigation, etc.
More recently disassemblers from the capstone and llvm (libraries, not
parsing the output of tools using those libraries to mimic binutils's
objdump output) were introduced.
So when all those methods are available, there is a static preference
for a series of attempts of disassembling a binary, with the 'llvm,
capstone, objdump' sequence being hard coded.
This patch allows users to change that sequence, specifying via a 'perf
config' 'annotate.disassemblers' entry which and in what order
disassemblers should be attempted.
As alluded to in the comments in the source code of this series, this
flexibility is useful for users and developers alike, elliminating the
requirement to rebuild the tool with some specific set of libraries to
see how the output of disassembling would be for one of these methods.
root@x1:~# rm -f ~/.perfconfig
root@x1:~# perf annotate -v --stdio2 update_load_avg
<SNIP>
symbol__disassemble:
filename=/usr/lib/debug/lib/modules/6.11.4-201.fc40.x86_64/vmlinux,
sym=update_load_avg, start=0xffffffffb6148fe0, en>
annotating [0x6ff7170]
/usr/lib/debug/lib/modules/6.11.4-201.fc40.x86_64/vmlinux :
[0x7407ca0] update_load_avg
Disassembled with llvm
annotate.disassemblers=llvm,capstone,objdump
Samples: 66 of event 'cpu_atom/cycles/P', 10000 Hz,
Event count (approx.): 5185444, [percent: local period]
update_load_avg()
/usr/lib/debug/lib/modules/6.11.4-201.fc40.x86_64/vmlinux
Percent 0xffffffff81148fe0 <update_load_avg>:
1.61 pushq %r15
pushq %r14
1.00 pushq %r13
movl %edx,%r13d
1.90 pushq %r12
pushq %rbp
movq %rsi,%rbp
pushq %rbx
movq %rdi,%rbx
subq $0x18,%rsp
15.14 movl 0x1a4(%rdi),%eax
root@x1:~# perf config annotate.disassemblers=capstone
root@x1:~# cat ~/.perfconfig
# this file is auto-generated.
[annotate]
disassemblers = capstone
root@x1:~#
root@x1:~# perf annotate -v --stdio2 update_load_avg
<SNIP>
Disassembled with capstone
annotate.disassemblers=capstone
Samples: 66 of event 'cpu_atom/cycles/P', 10000 Hz,
Event count (approx.): 5185444, [percent: local period]
update_load_avg()
/usr/lib/debug/lib/modules/6.11.4-201.fc40.x86_64/vmlinux
Percent 0xffffffff81148fe0 <update_load_avg>:
1.61 pushq %r15
pushq %r14
1.00 pushq %r13
movl %edx,%r13d
1.90 pushq %r12
pushq %rbp
movq %rsi,%rbp
pushq %rbx
movq %rdi,%rbx
subq $0x18,%rsp
15.14 movl 0x1a4(%rdi),%eax
root@x1:~# perf config annotate.disassemblers=objdump,capstone
root@x1:~# perf config annotate.disassemblers
annotate.disassemblers=objdump,capstone
root@x1:~# cat ~/.perfconfig
# this file is auto-generated.
[annotate]
disassemblers = objdump,capstone
root@x1:~# perf annotate -v --stdio2 update_load_avg
Executing: objdump --start-address=0xffffffff81148fe0 \
--stop-address=0xffffffff811497aa \
-d --no-show-raw-insn -S -C "$1"
Disassembled with objdump
annotate.disassemblers=objdump,capstone
Samples: 66 of event 'cpu_atom/cycles/P', 10000 Hz,
Event count (approx.): 5185444, [percent: local period]
update_load_avg()
/usr/lib/debug/lib/modules/6.11.4-201.fc40.x86_64/vmlinux
Percent
Disassembly of section .text:
ffffffff81148fe0 <update_load_avg>:
#define DO_ATTACH 0x4
ffffffff81148fe0 <update_load_avg>:
#define DO_ATTACH 0x4
#define DO_DETACH 0x8
/* Update task and its cfs_rq load average */
static inline void update_load_avg(struct cfs_rq *cfs_rq,
struct sched_entity *se,
int flags)
{
1.61 push %r15
push %r14
1.00 push %r13
mov %edx,%r13d
1.90 push %r12
push %rbp
mov %rsi,%rbp
push %rbx
mov %rdi,%rbx
sub $0x18,%rsp
}
/* rq->task_clock normalized against any time
this cfs_rq has spent throttled */
static inline u64 cfs_rq_clock_pelt(struct cfs_rq *cfs_rq)
{
if (unlikely(cfs_rq->throttle_count))
15.14 mov 0x1a4(%rdi),%eax
root@x1:~#
After adding a way to select the disassembler from the command line a
'perf test' comparing the output of the various diassemblers should be
introduced, to test these codebases.
Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Steinar H. Gunderson <sesse@google.com>
Link: https://lore.kernel.org/r/20241111151734.1018476-4-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add a few paragraphs on tool and hwmon events.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Yoshihiro Furudera <fj5100bi@fujitsu.com>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Ze Gao <zegao2021@gmail.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Junhao He <hejunhao3@huawei.com>
Cc: Weilin Wang <weilin.wang@intel.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Link: https://lore.kernel.org/r/20241109003759.473460-8-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Wasn't documented so far, mention that it is mostly used in the shell
regression tests.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Reviewed-by: James Clark <james.clark@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Clark Williams <williams@redhat.com>
Link: https://lore.kernel.org/r/20241020021842.1752770-4-acme@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
In Makefile.config for unwinding the name dwarf implies either
libunwind or libdw. Make it clearer that HAVE_DWARF_SUPPORT is really
just defined when libdw is present by renaming to HAVE_LIBDW_SUPPORT.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Leo Yan <leo.yan@arm.com>
Cc: Anup Patel <anup@brainfault.org>
Cc: Yang Jihong <yangjihong@bytedance.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Shenlin Liang <liangshenlin@eswincomputing.com>
Cc: Nick Terrell <terrelln@fb.com>
Cc: Guilherme Amadio <amadio@gentoo.org>
Cc: Steinar H. Gunderson <sesse@google.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Alexander Lobakin <aleksander.lobakin@intel.com>
Cc: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: James Clark <james.clark@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Chen Pei <cp0613@linux.alibaba.com>
Cc: Leo Yan <leo.yan@linux.dev>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Aditya Gupta <adityag@linux.ibm.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-riscv@lists.infradead.org
Cc: Bibo Mao <maobibo@loongson.cn>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Atish Patra <atishp@rivosinc.com>
Cc: Dima Kogan <dima@secretsauce.net>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Dr. David Alan Gilbert <linux@treblig.org>
Cc: linux-csky@vger.kernel.org
Link: https://lore.kernel.org/r/20241017001354.56973-11-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
As HAVE_DWARF_GETLOCATIONS_SUPPORT and HAVE_DWARF_CFI_SUPPORT always
match HAVE_DWARF_SUPPORT remove the macros and use
HAVE_DWARF_SUPPORT. If building the file is guarded by CONFIG_DWARF
then remove all ifs.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Anup Patel <anup@brainfault.org>
Cc: Yang Jihong <yangjihong@bytedance.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Shenlin Liang <liangshenlin@eswincomputing.com>
Cc: Nick Terrell <terrelln@fb.com>
Cc: Guilherme Amadio <amadio@gentoo.org>
Cc: Steinar H. Gunderson <sesse@google.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Alexander Lobakin <aleksander.lobakin@intel.com>
Cc: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: James Clark <james.clark@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Chen Pei <cp0613@linux.alibaba.com>
Cc: Leo Yan <leo.yan@linux.dev>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Aditya Gupta <adityag@linux.ibm.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-riscv@lists.infradead.org
Cc: Bibo Mao <maobibo@loongson.cn>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Atish Patra <atishp@rivosinc.com>
Cc: Dima Kogan <dima@secretsauce.net>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Dr. David Alan Gilbert <linux@treblig.org>
Cc: linux-csky@vger.kernel.org
Link: https://lore.kernel.org/r/20241017001354.56973-10-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
pre-migration wait time is the time that a task unnecessarily spends
on the runqueue of a CPU but doesn't get switched-in there. In terms
of tracepoints, it is the time between sched:sched_wakeup and
sched:sched_migrate_task.
Let's say a task woke up on CPU2, then it got migrated to CPU4 and
then it's switched-in to CPU4. So, here pre-migration wait time is
time that it was waiting on runqueue of CPU2 after it is woken up.
The general pattern for pre-migration to occur is:
sched:sched_wakeup
sched:sched_migrate_task
sched:sched_switch
The sched:sched_waking event is used to capture the wakeup time,
as it aligns with the existing code and only introduces a negligible
time difference.
pre-migrations are generally not useful and it increases migrations.
This metric would be helpful in testing patches mainly related to wakeup
and load-balancer code paths as better wakeup logic would choose an
optimal CPU where task would be switched-in and thereby reducing pre-
migrations.
The sample output(s) when -P or --pre-migrations is used:
=================
time cpu task name wait time sch delay run time pre-mig time
[tid/pid] (msec) (msec) (msec) (msec)
--------------- ------ ------------------------------ --------- --------- --------- ---------
38456.720806 [0001] schbench[28634/28574] 4.917 4.768 1.004 0.000
38456.720810 [0001] rcu_preempt[18] 3.919 0.003 0.004 0.000
38456.721800 [0006] schbench[28779/28574] 23.465 23.465 1.999 0.000
38456.722800 [0002] schbench[28773/28574] 60.371 60.237 3.955 60.197
38456.722806 [0001] schbench[28634/28574] 0.004 0.004 1.996 0.000
38456.722811 [0001] rcu_preempt[18] 1.996 0.005 0.005 0.000
38456.723800 [0000] schbench[28833/28574] 4.000 4.000 3.999 0.000
38456.723800 [0004] schbench[28762/28574] 42.951 42.839 3.999 39.867
38456.723802 [0007] schbench[28812/28574] 43.947 43.817 3.999 40.866
38456.723804 [0001] schbench[28587/28574] 7.935 7.822 0.993 0.000
Signed-off-by: Madadi Vineeth Reddy <vineethr@linux.ibm.com>
Reviewed-by: Tim Chen <tim.c.chen@linux.intel.com>
Link: https://lore.kernel.org/r/20241004170756.18064-1-vineethr@linux.ibm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
The original commit message:
"
Use current sort mechanism but the real .se_cmp() just returns 0 so
that new columns "Predicted", "Abort" and "Cycles" are created in display
but actually these keys are not the sort keys.
For example:
Overhead Source:Line Symbol Shared Object Predicted Abort Cycles
........ ............ ........ ............. ......... ..... ......
38.25% div.c:45 [.] main div 97.6% 0 3
"
Update missed commit from series "perf report: Show branch flags/cycles
in --branch-history callgraph view" to apply to current repository so that
new columns described above are visible.
Link to original series:
https://lore.kernel.org/lkml/1477876794-30749-1-git-send-email-yao.jin@linux.intel.com/
Reported-by: Dr. David Alan Gilbert <linux@treblig.org>
Suggested-by: Kan Liang <kan.liang@linux.intel.com>
Co-developed-by: Jin Yao <yao.jin@linux.intel.com>
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Tested-by: Thomas Falcon <thomas.falcon@intel.com>
Signed-off-by: Thomas Falcon <thomas.falcon@intel.com>
Link: https://lore.kernel.org/r/20241010184046.203822-1-thomas.falcon@intel.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
There is a difference between the SYNOPSIS section of the help message
and the man page (tools/perf/Documentation/perf-list.txt) for the perf
list command. After checking, we found that the help message reflected
the latest specifications. Therefore, revised the SYNOPSIS section of
the man page to match the help message.
Signed-off-by: Yoshihiro Furudera <fj5100bi@fujitsu.com>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Weilin Wang <weilin.wang@intel.com>
Cc: Liang
Link: https://lore.kernel.org/r/20241003002404.2592094-1-fj5100bi@fujitsu.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
This can be used to get config values like which objdump Perf uses for
disassembly.
Reviewed-by: Leo Yan <leo.yan@arm.com>
Signed-off-by: James Clark <james.clark@linaro.org>
Tested-by: Ganapatrao Kulkarni <gankulkarni@os.amperecomputing.com>
Cc: Ben Gainey <ben.gainey@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Ruidong Tian <tianruidong@linux.alibaba.com>
Cc: Leo Yan <leo.yan@linux.dev>
Cc: Benjamin Gray <bgray@linux.ibm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: coresight@lists.linaro.org
Cc: John Garry <john.g.garry@oracle.com>
Cc: scclevenger@os.amperecomputing.com
Link: https://lore.kernel.org/r/20240916135743.1490403-4-james.clark@linaro.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Fix two inconsistencies in feature names as discussed in [1]:
1. Rename "dwarf-unwind-support" to "dwarf-unwind"
2. 'get_cpuid' feature and 'HAVE_AUXTRACE_SUPPORT' names don't
look related, change the feature name to 'auxtrace' to match the
macro name, as 'get_cpuid' string is not used anywhere to check the
feature presence
[1]: https://lore.kernel.org/linux-perf-users/ZoRw5we4HLSTZND6@x1/
Suggested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Aditya Gupta <adityag@linux.ibm.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Disha Goel <disgoel@linux.vnet.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240904190132.415212-7-adityag@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently the presence of a feature is checked with a combination of
perf version --build-options and greps, such as:
perf version --build-options | grep " on .* HAVE_FEATURE"
Instead of this, introduce a subcommand "perf check feature", with which
scripts can test for presence of a feature, such as:
perf check feature HAVE_FEATURE
'perf check feature' command is expected to have exit status of 0 if
feature is built-in, and 1 if it's not built-in or if feature is not known.
Multiple features can also be passed as a comma-separated list, in which
case the exit status will be 1 only if all of the passed features are
built-in. For example, with below command, it will have exit status of 0
only if both libtraceevent and bpf are enabled, else 1 in all other cases
perf check feature libtraceevent,bpf
The arguments are case-insensitive.
An array 'supported_features' has also been introduced that can be used by
other commands like 'perf version --build-options', so that new features
can be added in one place, with the array
Committer testing:
$ perf check feature libtraceevent,bpf
libtraceevent: [ on ] # HAVE_LIBTRACEEVENT
bpf: [ on ] # HAVE_LIBBPF_SUPPORT
$ perf check feature libtraceevent
libtraceevent: [ on ] # HAVE_LIBTRACEEVENT
$ perf check feature bpf
bpf: [ on ] # HAVE_LIBBPF_SUPPORT
$ perf check -q feature bpf && echo "BPF support is present"
BPF support is present
$ perf check -q feature Bogus && echo "Bogus support is present"
$
Reviewed-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Aditya Gupta <adityag@linux.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Disha Goel <disgoel@linux.vnet.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240904061836.55873-3-adityag@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The --show-prio option is used to display the priority of task.
It is disabled by default, which is consistent with original behavior.
The display format is xxx (priority does not change during task running)
or xxx->yyy (priority changes during task running)
Testcase:
# perf sched record nice -n 9 true
[ perf record: Woken up 0 times to write data ]
[ perf record: Captured and wrote 0.497 MB perf.data ]
# perf sched timehist -h
Usage: perf sched timehist [<options>]
-C, --cpu <cpu> list of cpus to profile
-D, --dump-raw-trace dump raw trace in ASCII
-f, --force don't complain, do it
-g, --call-graph Display call chains if present (default on)
-I, --idle-hist Show idle events only
-i, --input <file> input file name
-k, --vmlinux <file> vmlinux pathname
-M, --migrations Show migration events
-n, --next Show next task
-p, --pid <pid[,pid...]>
analyze events only for given process id(s)
-s, --summary Show only syscall summary with statistics
-S, --with-summary Show all syscalls and summary with statistics
-t, --tid <tid[,tid...]>
analyze events only for given thread id(s)
-V, --cpu-visual Add CPU visual
-v, --verbose be more verbose (show symbol address, etc)
-w, --wakeups Show wakeup events
--kallsyms <file>
kallsyms pathname
--max-stack <n> Maximum number of functions to display backtrace.
--show-prio Show task priority
--state Show task state when sched-out
--symfs <directory>
Look for files with symbols relative to this directory
--time <str> Time span for analysis (start,stop)
# perf sched timehist
Samples of sched_switch event do not have callchains.
time cpu task name wait time sch delay run time
[tid/pid] (msec) (msec) (msec)
--------------- ------ ------------------------------ --------- --------- ---------
23952.006537 [0000] perf[534] 0.000 0.000 0.000
23952.006593 [0000] migration/0[19] 0.000 0.014 0.056
23952.006899 [0001] perf[534] 0.000 0.000 0.000
23952.006947 [0001] migration/1[22] 0.000 0.015 0.047
23952.007138 [0002] perf[534] 0.000 0.000 0.000
<SNIP>
# perf sched timehist --show-prio
Samples of sched_switch event do not have callchains.
time cpu task name prio wait time sch delay run time
[tid/pid] (msec) (msec) (msec)
--------------- ------ ------------------------------ -------- --------- --------- ---------
23952.006537 [0000] perf[534] 120 0.000 0.000 0.000
23952.006593 [0000] migration/0[19] 0 0.000 0.014 0.056
23952.006899 [0001] perf[534] 120 0.000 0.000 0.000
<SNIP>
23952.034843 [0003] nice[535] 120->129 0.189 0.024 23.314
<SNIP>
23952.053838 [0005] rcu_preempt[16] 120 3.993 0.000 0.023
23952.053990 [0005] <idle> 120 0.023 0.023 0.152
23952.054137 [0006] <idle> 120 1.427 1.427 17.855
23952.054278 [0007] <idle> 120 0.506 0.506 1.650
Signed-off-by: Yang Jihong <yangjihong@bytedance.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240819033016.2427235-2-yangjihong@bytedance.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
TPEBS (Timed PEBS(Precise Event-Based Sampling)) is a new feature Intel
PMU from Granite Rapids microarchitecture.
It will be used in new TMA (Top-Down Microarchitecture Analysis)
releases.
Add related introduction to documents while adding new code to support
it in 'perf stat'.
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Weilin Wang <weilin.wang@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Caleb Biggers <caleb.biggers@intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Perry Taylor <perry.taylor@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Samantha Alt <samantha.alt@intel.com>
Link: https://lore.kernel.org/r/20240720062102.444578-8-weilin.wang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Current description for the AUX trace buffer size is misleading. When a
user specifies the option '-m,512M', it represents a size value in bytes
(512MiB) but not 512M pages (512M x 4KiB regard to a page of 4KiB).
Make the document clear that the normal buffer and the AUX tracing
buffer share the same semantics. Syncs the documents for consistent
text.
Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Leo Yan <leo.yan@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240812093459.2575278-1-leo.yan@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Similarly to other subcommands (like report, top), it would be handy to
provide a path for addr2line command.
Signed-off-by: Martin Liska <martin.liska@hey.com>
Cc: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/eadc3e36-029d-4848-9d69-272fe5a83a26@foxlink.cz
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add a common options section and move some items to the section. Also
add description of new options to report options.
Suggested-by: Ian Rogers <irogers@google.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/lkml/20240802180913.1023886-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To allow BPF filters for unprivileged users it needs to pin the BPF
objects to BPF-fs first. Let's add a new option to pin and unpin the
objects easily. I'm not sure 'perf record' is a right place to do this
but I don't have a better idea right now.
$ sudo perf record --setup-filter pin
The above command would pin BPF program and maps for the filter when the
system has BPF-fs (usually at /sys/fs/bpf/). To unpin the objects,
users can run the following command (as root).
$ sudo perf record --setup-filter unpin
Committer testing:
root@number:~# perf record --setup-filter pin
root@number:~# ls -la /sys/fs/bpf/perf_filter/
total 0
drwxr-xr-x. 2 root root 0 Jul 31 10:43 .
drwxr-xr-t. 3 root root 0 Jul 31 10:43 ..
-rw-rw-rw-. 1 root root 0 Jul 31 10:43 dropped
-rw-rw-rw-. 1 root root 0 Jul 31 10:43 filters
-rwxrwxrwx. 1 root root 0 Jul 31 10:43 perf_sample_filter
-rw-rw-rw-. 1 root root 0 Jul 31 10:43 pid_hash
-rw-------. 1 root root 0 Jul 31 10:43 sample_f_rodata
root@number:~# ls -la /sys/fs/bpf/perf_filter/perf_sample_filter
-rwxrwxrwx. 1 root root 0 Jul 31 10:43 /sys/fs/bpf/perf_filter/perf_sample_filter
root@number:~#
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20240703223035.2024586-8-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The 'perf ftrace profile' command is to get function execution profiles
using function-graph tracer so that users can see the total, average,
max execution time as well as the number of invocations easily.
The following is a profile for the perf_event_open syscall.
$ sudo perf ftrace profile -G __x64_sys_perf_event_open -- \
perf stat -e cycles -C1 true 2> /dev/null | head
# Total (us) Avg (us) Max (us) Count Function
65.611 65.611 65.611 1 __x64_sys_perf_event_open
30.527 30.527 30.527 1 anon_inode_getfile
30.260 30.260 30.260 1 __anon_inode_getfile
29.700 29.700 29.700 1 alloc_file_pseudo
17.578 17.578 17.578 1 d_alloc_pseudo
17.382 17.382 17.382 1 __d_alloc
16.738 16.738 16.738 1 kmem_cache_alloc_lru
15.686 15.686 15.686 1 perf_event_alloc
14.012 7.006 11.264 2 obj_cgroup_charge
#
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Changbin Du <changbin.du@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lore.kernel.org/lkml/20240729004127.238611-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The 'graph-tail' option is to print function name as a comment at the end.
This is useful when a large function is mixed with other functions
(possibly from different CPUs).
For example,
$ sudo perf ftrace -- perf stat true
...
1) | get_unused_fd_flags() {
1) | alloc_fd() {
1) 0.178 us | _raw_spin_lock();
1) 0.187 us | expand_files();
1) 0.169 us | _raw_spin_unlock();
1) 1.211 us | }
1) 1.503 us | }
$ sudo perf ftrace --graph-opts tail -- perf stat true
...
1) | get_unused_fd_flags() {
1) | alloc_fd() {
1) 0.099 us | _raw_spin_lock();
1) 0.083 us | expand_files();
1) 0.081 us | _raw_spin_unlock();
1) 0.601 us | } /* alloc_fd */
1) 0.751 us | } /* get_unused_fd_flags */
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Changbin Du <changbin.du@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lore.kernel.org/lkml/20240729004127.238611-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Records the commands for cross compilation with two methods.
The first method relies on Multiarch. The second approach is to explicitly
specify the PKG_CONFIG variables, which is widely used in build system
(like Buildroot, Yocto, etc).
Co-developed-by: James Clark <james.clark@arm.com>
Signed-off-by: James Clark <james.clark@arm.com>
Signed-off-by: Leo Yan <leo.yan@arm.com>
Tested-by: Ian Rogers <irogers@google.com>
Cc: amadio@gentoo.org
Cc: Thomas Richter <tmricht@linux.ibm.com>
Link: https://lore.kernel.org/r/20240717082211.524826-7-leo.yan@arm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
By default, perf sched map prints sched-in events for all the tasks
which may not be required all the time as it prints lot of symbols
and rows to the terminal.
With --task-name option, one could specify the specific task name
for which the map has to be shown. This would help in analyzing the
CPU usage patterns easier for that specific task. Since multiple
PID's might have the same task name, using task-name filter
would be more useful for debugging.
For other tasks, instead of printing the symbol, '-' is printed and
the same '.' is used to represent idle. '-' is used instead of symbol
for other tasks because it helps in clear visualization of task
of interest and secondly the symbol itself doesn't mean anything
because the sched-in of that symbol will not be printed(first sched-in
contains pid and the corresponding symbol).
When using the --task-name option, the sched-out time is represented
by a '*-'. Since not all task sched-in events are printed, the sched-out
time of the relevant task might be lost. This representation ensures
that the sched-out time of the interested task is not overlooked.
6.10.0-rc1
==========
*A0 131040.639793 secs A0 => migration/0:19
*. 131040.639801 secs . => swapper:0
. *B0 131040.639830 secs B0 => migration/1:24
. *. 131040.639836 secs
. . *C0 131040.640108 secs C0 => migration/2:30
. . *. 131040.640163 secs
. . . *D0 131040.640386 secs D0 => migration/3:36
. . . *. 131040.640395 secs
6.10.0-rc1 + patch (--task-name wdavdaemon)
=============
. *A0 . . . . - . 131040.641346 secs A0 => wdavdaemon:62509
. A0 *B0 . . . - . 131040.641378 secs B0 => wdavdaemon:62274
- *- B0 . . . - . 131040.641379 secs
*C0 . B0 . . . . . 131040.641572 secs C0 => wdavdaemon:62283
C0 . B0 . *D0 . . . 131040.641572 secs D0 => wdavdaemon:62277
C0 . B0 . D0 . *E0 . 131040.641578 secs E0 => wdavdaemon:62270
*- . B0 . D0 . E0 . 131040.641581 secs
. . B0 . D0 . *- . 131040.641583 secs
Reviewed-and-tested-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Madadi Vineeth Reddy <vineethr@linux.ibm.com>
Cc: Chen Yu <yu.c.chen@intel.com>
Link: https://lore.kernel.org/r/20240707182716.22054-2-vineethr@linux.ibm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Currently, the -r/--repeat option accepts values from 0 and complains
for -1. The help section specifies:
-r, --repeat <n> repeat the workload replay N times (-1: infinite)
The -r -1 option raises an error because replay_repeat is defined as
an unsigned int.
In the current implementation, the workload is repeated n times when
-r <n> is used, except when n is 0.
When -r is set to 0, the workload is also repeated once. This happens
because when -r=0, the run_one_test function is not called. (Note that
mutex unlocking, which is essential for child threads spawned to emulate
the workload, happens in run_one_test.) However, mutex unlocking is
still performed in the destroy_tasks function. Thus, -r=0 results in the
workload running once coincidentally.
To clarify and maintain the existing logic for -r >= 1 (which runs the
workload the specified number of times) and to fix the issue with infinite
runs, make -r=0 perform an infinite run.
Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: Madadi Vineeth Reddy <vineethr@linux.ibm.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Link: https://lore.kernel.org/r/20240628071821.15264-1-vineethr@linux.ibm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
When using perf timehist, sch delay is only computed for a waking task,
not for a pre empted task. This patches changes sch delay to account for
both. This makes sense as testing scheduling policy need to consider the
effect of scheduling delay globally, not only for waking tasks.
Example of `perf timehist` report before the patch for `stress` task
competing with each other.
First column is wait time, second column sch delay, third column
runtime.
1.492060 [0000] s stress[81] 1.999 0.000 2.000 R next: stress[83]
1.494060 [0000] s stress[83] 2.000 0.000 2.000 R next: stress[81]
1.496060 [0000] s stress[81] 2.000 0.000 2.000 R next: stress[83]
1.498060 [0000] s stress[83] 2.000 0.000 1.999 R next: stress[81]
After the patch, it looks like this (note that all wait time is not zero
anymore):
1.492060 [0000] s stress[81] 1.999 1.999 2.000 R next: stress[83]
1.494060 [0000] s stress[83] 2.000 2.000 2.000 R next: stress[81]
1.496060 [0000] s stress[81] 2.000 2.000 2.000 R next: stress[83]
1.498060 [0000] s stress[83] 2.000 2.000 1.999 R next: stress[81]
Signed-off-by: Fernand Sieber <sieberf@amazon.com>
Reviewed-by: Madadi Vineeth Reddy <vineethr@linux.ibm.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240618090339.87482-1-sieberf@amazon.com
Add a perf man page document that describes how to exploit AMD IBS with
Linux perf. Brief intro about IBS and simple one-liner examples will help
naive users to get started. This is not meant to be an exhaustive IBS
guide. User should refer latest AMD64 Architecture Programmer's Manual
for detailed description of IBS.
Usage:
$ man perf-amd-ibs
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: ananth.narayan@amd.com
Cc: sandipan.das@amd.com
Cc: santosh.shukla@amd.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240620054104.815-1-ravi.bangoria@amd.com
Change "perf lock info" argument handling to:
Display both map and thread info (rather than an error) when neither are
specified.
Display both map and thread info (rather than just thread info) when
both are requested.
Signed-off-by: Nick Forrington <nick.forrington@arm.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240513091413.738537-2-nick.forrington@arm.com
Allow filters to be added to perf top events. One use is to workaround
issues with:
```
$ perf top --uid="$(id -u)"
```
which tries to scan /proc find processes belonging to the uid and can
fail in such a pid terminates between the scan and the
perf_event_open reporting:
```
Error:
The sys_perf_event_open() syscall returned with 3 (No such process) for event (cycles:P).
/bin/dmesg | grep -i perf may provide additional information.
```
A similar filter:
```
$ perf top -e cycles:P --filter "uid == $(id -u)"
```
doesn't fail this way.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: bpf@vger.kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240524205227.244375-4-irogers@google.com
Allow the BPF filter to use the uid and gid terms determined by the
bpf_get_current_uid_gid BPF helper. For example, the following will
record the cpu-clock event system wide discarding samples that don't
belong to the current user.
$ perf record -e cpu-clock --filter "uid == $(id -u)" -a sleep 0.1
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: bpf@vger.kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240524205227.244375-3-irogers@google.com
Assorted typo fixes.
Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: James Clark <james.clark@arm.com>
Cc: Changbin Du <changbin.du@huawei.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240521223555.858859-1-irogers@google.com
Rename 'Switches' to 'Count' and document metrics shown for perf
sched latency output. Also add options possible with perf sched
latency.
Initially, after seeing the output of 'perf sched latency', the term
'Switches' seemed like it's the number of context switches-in for a
particular task, but upon going through the code, it was observed that
it's actually keeping track of number of times a delay was calculated so
that it is used in calculation of the average delay.
Actually, the switches here is a subset of number of context switches-in
because there are some cases where the count is not incremented in
switch-in handler 'add_sched_in_event'. For example when a task is
switched-in while it's state is not ready to run(!= THREAD_WAIT_CPU).
commit d9340c1db3 ("perf sched: Display time in milliseconds,
reorganize output") changed it from the original count to switches.
So, renamed switches to count to make things a bit more clearer and
added the metrics description of latency in the document.
Reviewed-by: Aditya Gupta <adityag@linux.ibm.com>
Signed-off-by: Madadi Vineeth Reddy <vineethr@linux.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240328090005.8321-1-vineethr@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We can't default to doing parallel tests as there are tests that compete
for the same resources and thus clash, for instance tests that put in
place 'perf probe' probes, that clean the probes without regard to other
tests needs, ARM64 coresight tests, Intel PT ones, etc.
So reintroduce --p/--parallel and make -S/--sequential the default.
We need to come up with infrastructure that state which tests can't run
in parallel because they need exclusive access to some resource,
something as simple as "probes" that would then avoid 'perf probe' tests
from running while other such test is running, or make the tests more
resilient, till then we can't use parallel mode as default.
While at it, document all these options in the 'perf test' man page.
Reported-by: Adrian Hunter <adrian.hunter@intel.com>
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Reported-by: James Clark <james.clark@arm.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/Ziwm18BqIn_vc1vn@x1
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Document that 'b' is used as a modifier to make an event use a BPF
counter.
Fixes: 01bd8efcec ("perf stat: Introduce ':b' modifier")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Song Liu <song@kernel.org>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Link: https://lore.kernel.org/r/20240416170014.985191-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add weight1, weight2 and weight3 fields to -F/--fields and their aliases
like 'ins_lat', 'p_stage_cyc' and 'retire_lat'. Note that they are in
the sort keys too but the difference is that output fields will sum up
the weight values and display the average.
In the sort key, users can see the distribution of weight value and I
think it's confusing we have local vs. global weight for the same weight.
For example, I experiment with mem-loads events to get the weights. On
my laptop, it seems only weight1 field is supported.
$ perf mem record -- perf test -w noploop
Let's look at the noploop function only. It has 7 samples.
$ perf script -F event,ip,sym,weight | grep noploop
# event weight ip sym
cpu/mem-loads,ldlat=30/P: 43 55b3c122bffc noploop
cpu/mem-loads,ldlat=30/P: 48 55b3c122bffc noploop
cpu/mem-loads,ldlat=30/P: 38 55b3c122bffc noploop <--- same weight
cpu/mem-loads,ldlat=30/P: 38 55b3c122bffc noploop <--- same weight
cpu/mem-loads,ldlat=30/P: 59 55b3c122bffc noploop
cpu/mem-loads,ldlat=30/P: 33 55b3c122bffc noploop
cpu/mem-loads,ldlat=30/P: 38 55b3c122bffc noploop <--- same weight
When you use the 'weight' sort key, it'd show entries with a separate
weight value separately. Also note that the first entry has 3 samples
with weight value 38, so they are displayed together and the weight
value is the sum of 3 samples (114 = 38 * 3).
$ perf report -n -s +weight | grep -e Weight -e noploop
# Overhead Samples Command Shared Object Symbol Weight
0.53% 3 perf perf [.] noploop 114
0.18% 1 perf perf [.] noploop 59
0.18% 1 perf perf [.] noploop 48
0.18% 1 perf perf [.] noploop 43
0.18% 1 perf perf [.] noploop 33
If you use 'local_weight' sort key, you can see the actual weight.
$ perf report -n -s +local_weight | grep -e Weight -e noploop
# Overhead Samples Command Shared Object Symbol Local Weight
0.53% 3 perf perf [.] noploop 38
0.18% 1 perf perf [.] noploop 59
0.18% 1 perf perf [.] noploop 48
0.18% 1 perf perf [.] noploop 43
0.18% 1 perf perf [.] noploop 33
But when you use the -F/--field option instead, you can see the average
weight for the while noploop function (as it won't group samples by
weight value and use the default 'comm,dso,sym' sort keys).
$ perf report -n -F +weight | grep -e Weight -e noploop
Warning:
--fields weight shows the average value unlike in the --sort key.
# Overhead Samples Weight1 Command Shared Object Symbol
1.23% 7 42.4 perf perf [.] noploop
The weight1 field shows the average value:
(38 * 3 + 59 + 48 + 43 + 33) / 7 = 42.4
Also it'd show the warning that 'weight' field has the average value.
Using 'weight1' can remove the warning.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20240411181718.2367948-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The question of exactly when KPTI needs to be disabled comes up a lot
because it doesn't always need to be done. Add the relevant kernel
function and some examples that describe the behavior.
Also describe the interrupt requirement and that no error message will
be printed if this isn't met.
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: James Clark <james.clark@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240312132508.423320-1-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Now perf can show assembly instructions with libcapstone for x86, and the
capstone is better in general.
Signed-off-by: Changbin Du <changbin.du@huawei.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: changbin.du@gmail.com
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240217074046.4100789-6-changbin.du@huawei.com
Some platforms have 'cluster' topology and CPUs in the cluster will
share resources like L3 Cache Tag (for HiSilicon Kunpeng SoC) or L2
cache (for Intel Jacobsville). Currently parsing and building cluster
topology have been supported since [1].
perf stat has already supported aggregation for other topologies like
die or socket, etc. It'll be useful to aggregate per-cluster to find
problems like L3T bandwidth contention.
This patch add support for "--per-cluster" option for per-cluster
aggregation. Also update the docs and related test. The output will
be like:
[root@localhost tmp]# perf stat -a -e LLC-load --per-cluster -- sleep 5
Performance counter stats for 'system wide':
S56-D0-CLS158 4 1,321,521,570 LLC-load
S56-D0-CLS594 4 794,211,453 LLC-load
S56-D0-CLS1030 4 41,623 LLC-load
S56-D0-CLS1466 4 41,646 LLC-load
S56-D0-CLS1902 4 16,863 LLC-load
S56-D0-CLS2338 4 15,721 LLC-load
S56-D0-CLS2774 4 22,671 LLC-load
[...]
On a legacy system without cluster or cluster support, the output will
be look like:
[root@localhost perf]# perf stat -a -e cycles --per-cluster -- sleep 1
Performance counter stats for 'system wide':
S56-D0-CLS0 64 18,011,485 cycles
S7182-D0-CLS0 64 16,548,835 cycles
Note that this patch doesn't mix the cluster information in the outputs
of --per-core to avoid breaking any tools/scripts using it.
Note that perf recently supports "--per-cache" aggregation, but it's not
the same with the cluster although cluster CPUs may share some cache
resources. For example on my machine all clusters within a die share the
same L3 cache:
$ cat /sys/devices/system/cpu/cpu0/cache/index3/shared_cpu_list
0-31
$ cat /sys/devices/system/cpu/cpu0/topology/cluster_cpus_list
0-3
[1] commit c5e22feffd ("topology: Represent clusters of CPUs within a die")
Tested-by: Jie Zhan <zhanjie9@hisilicon.com>
Reviewed-by: Tim Chen <tim.c.chen@linux.intel.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Cc: james.clark@arm.com
Cc: 21cnbao@gmail.com
Cc: prime.zeng@hisilicon.com
Cc: Jonathan.Cameron@huawei.com
Cc: fanghao11@huawei.com
Cc: linuxarm@huawei.com
Cc: tim.c.chen@intel.com
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240208024026.2691-1-yangyicong@huawei.com
perf script exposes the evsel_name to python scripts as part of the data
passed to the sample or tracepoint handler function, and it passes the id and
stream_id to the throttled/unthrottled handler functions. This makes matching
throttle events and samples difficult.
To make this possible, this change exposes the sample id and stream_id values
to the script.
Signed-off-by: Ben Gainey <ben.gainey@arm.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: will@kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240123103137.1890779-2-ben.gainey@arm.com
