This patch modifies the -I/--int-regs option to enablepassing the name
of the registers to sample on interrupt. Registers can be specified by
their symbolic names. For instance on x86, --intr-regs=ax,si.
The motivation is to reduce the size of the perf.data file and the
overhead of sampling by only collecting the registers useful to a
specific analysis. For instance, for value profiling, sampling only the
registers used to passed arguements to functions.
With no parameter, the --intr-regs still records all possible registers
based on the architecture.
To name registers, it is necessary to use the long form of the option,
i.e., --intr-regs:
$ perf record --intr-regs=si,di,r8,r9 .....
To record any possible registers:
$ perf record -I .....
$ perf report --intr-regs ...
To display the register, one can use perf report -D
To list the available registers:
$ perf record --intr-regs=\?
available registers: AX BX CX DX SI DI BP SP IP FLAGS CS SS R8 R9 R10 R11 R12 R13 R14 R15
Signed-off-by: Stephane Eranian <eranian@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1441039273-16260-4-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch allows 'perf record' to exclude events issued by perf itself
by '--exclude-perf' option.
Before this patch, when doing something like:
# perf record -a -e syscalls:sys_enter_write <cmd>
One could easily get result like this:
# /tmp/perf report --stdio
...
# Overhead Command Shared Object Symbol
# ........ ....... .................. ....................
#
99.99% perf libpthread-2.18.so [.] __write_nocancel
0.01% ls libc-2.18.so [.] write
0.01% sshd libc-2.18.so [.] write
...
Where most events are generated by perf itself.
A shell trick can be done to filter perf itself out:
# cat << EOF > ./tmp
> #!/bin/sh
> exec perf record -e ... --filter="common_pid != \$\$" -a sleep 10
> EOF
# chmod a+x ./tmp
# ./tmp
However, doing so is user unfriendly.
This patch extracts evsel iteration framework introduced by patch 'perf
record: Apply filter to all events in a glob matching' into
foreach_evsel_in_last_glob(), and makes exclude_perf() function append
new filter expression to each evsel selected by a '-e' selector.
To avoid losing filters if user pass '--filter' after '--exclude-perf',
this patch uses perf_evsel__append_filter() in both case, instead of
perf_evsel__set_filter() which removes old filter. As a side effect, now
it is possible to use multiple '--filter' option for one selector. They
are combinded with '&&'.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1436513770-8896-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Because there's too many options and I cannot read, I frequently get
confused between -c and -P, and try to do things like:
perf record -P 50000 -- foo
Which does not work; try and make the option description slightly longer
and hopefully less confusing.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150610144850.GP19282@twins.programming.kicks-ass.net
[ Do those changes on the man page as well ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The size of perf.data is missing update in no-buildid mode, which gives
wrong output result.
Before this patch:
$ perf.perf record -B -e syscalls:sys_enter_open uname
Linux
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.000 MB perf.data ]
After this patch:
$ perf.perf record -B -e syscalls:sys_enter_open uname
Linux
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.001 MB perf.data ]
Signed-off-by: He Kuang <hekuang@huawei.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1432819050-30511-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add an index of AUX area tracing events within a perf.data file.
perf record uses a special user event PERF_RECORD_FINISHED_ROUND to
enable sorting of events in chunks instead of having to sort all events
altogether.
AUX area tracing events contain data that can span back to the very
beginning of the recording period. i.e. they do not obey the rules of
PERF_RECORD_FINISHED_ROUND.
By adding an index, AUX area tracing events can be found in advance and
the PERF_RECORD_FINISHED_ROUND approach works as usual.
The index is recorded with the auxtrace feature in the perf.data file.
A session reads the index but does not process it. An AUX area decoder
can queue all the AUX area data in advance using
auxtrace_queues__process_index() or otherwise process the index in some
custom manner.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1430404667-10593-3-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Use of a bad filter currently generates the message:
Error: failed to set filter with 22 (Invalid argument)
Add the event name to make it clear to which event the filter
failed to apply:
Error: Failed to set filter "foo" on event sched:sg_lb_stats: 22: Invalid argument
To test it use something like:
# perf record -e sched:sched_switch -e sched:*fork --filter parent_pid==1 -e sched:*wait* --filter bla usleep 1
Error: failed to set filter "bla" on event sched:sched_stat_iowait with 22 (Invalid argument)
#
Based-on-a-patch-by: David Ahern <dsahern@gmail.com>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-d7gq2fjvaecozp9o2i0siifu@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
After perf record finishes, it prints file size and number of samples in
the file but this info is wrong since it assumes typical sample size of
24 bytes and divides file size by the value.
However as we post-process recorded samples for build-id, it can show
correct number like below. If build-id post-processing is not requested
just omit the wrong number of samples.
$ perf record noploop 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.159 MB perf.data (3989 samples) ]
$ perf report --stdio -n
# To display the perf.data header info, please use --header/--header-only options.
#
# Samples: 3K of event 'cycles'
# Event count (approx.): 3771330663
#
# Overhead Samples Command Shared Object Symbol
# ........ ............ ....... ................ ..........................
#
99.90% 3982 noploop noploop [.] main
0.09% 1 noploop ld-2.17.so [.] _dl_check_map_versions
0.01% 1 noploop [kernel.vmlinux] [k] setup_arg_pages
0.00% 5 noploop [kernel.vmlinux] [k] intel_pmu_enable_all
Reported-by: Milian Wolff <mail@milianw.de>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1422518843-25818-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When perf record finishes a session, it pre-processes samples in order
to write build-id info from DSOs that had samples.
During this process it'll call map__load() for the kernel map, and it
ends up calling dso__load_vmlinux_path() which replaces dso->long_name.
But this function checks kernel's build-id before searching vmlinux path
so it'll end up with a cryptic name, the pathname for the entry in the
~/.debug cache, which can be confusing to users.
This patch adds a flag to skip the build-id check during record, so
that it'll have the original vmlinux path for the kernel dso->long_name,
not the entry in the ~/.debug cache.
Before:
# perf record -va sleep 3
mmap size 528384B
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.196 MB perf.data (~8545 samples) ]
Looking at the vmlinux_path (7 entries long)
Using /home/namhyung/.debug/.build-id/f0/6e17aa50adf4d00b88925e03775de107611551 for symbols
After:
# perf record -va sleep 3
mmap size 528384B
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.193 MB perf.data (~8432 samples) ]
Looking at the vmlinux_path (7 entries long)
Using /lib/modules/3.16.4-1-ARCH/build/vmlinux for symbols
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1415063674-17206-7-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently vmlinux_path__init() only tries to find vmlinux file from
current directory, /boot and some canonical directories with version
number of the running kernel. This can be a problem when reporting old
data recorded on a kernel version not running currently.
We can use --symfs option for this but it's annoying for user to do it
always. As we already have the info in the perf.data file, it can be
changed to use it for the search automatically.
Before:
$ perf report
...
# Samples: 4K of event 'cpu-clock'
# Event count (approx.): 1067250000
#
# Overhead Command Shared Object Symbol
# ........ .......... ................. ..............................
71.87% swapper [kernel.kallsyms] [k] recover_probed_instruction
After:
# Overhead Command Shared Object Symbol
# ........ .......... ................. ....................
71.87% swapper [kernel.kallsyms] [k] native_safe_halt
This requires to change signature of symbol__init() to receive struct
perf_session_env *.
Reported-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1407825645-24586-14-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If the perf record command is interrupted in record__mmap_read_all
function, the 'done' is set and err has the latest poll return
value, which is most likely positive number (= number of pollfds
ready to read).
This 'positive err' is then propagated to the exit code, resulting
in not finishing the perf.data header properly, causing following
error in report:
# perf record -F 50000 -a
---
make the system real busy, so there's more chance
to interrupt perf in event writing code
---
^C[ perf record: Woken up 16 times to write data ]
[ perf record: Captured and wrote 30.292 MB perf.data (~1323468 samples) ]
# perf report --stdio > /dev/null
WARNING: The perf.data file's data size field is 0 which is unexpected.
Was the 'perf record' command properly terminated?
Fixing this by checking for positive poll return value
and setting err to 0.
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1401732126-19465-1-git-send-email-jolsa@kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Currently perf record doesn't propagate the exit status of a workload
given by the command line. But sometimes it'd useful if it's
propagated so that a monitoring script can handle errors
appropriately.
To do that, it moves most of logic out of the exit handlers and run
them directly in the __cmd_record(). The only thing needs to be done
in the handler is propagating terminating signal so that the shell can
terminate its loop properly when Ctrl-C was pressed. Also it cleaned
up the resource management code in record__exit().
With this change, perf record returns the child exit status in case of
normal termination and send signal to itself when terminated by signal.
Example run of Stephane's case:
$ perf record true && echo yes || echo no
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.013 MB perf.data (~589 samples) ]
yes
$ perf record false && echo yes || echo no
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.013 MB perf.data (~589 samples) ]
no
Jiri's case (error in parent):
$ perf record -m 10G true && echo yes || echo no
rounding mmap pages size to 17179869184 bytes (4194304 pages)
failed to mmap with 12 (Cannot allocate memory)
no
$ ulimit -n 6
$ perf record sleep 1 && echo yes || echo no
failed to create 'go' pipe: Too many open files
Couldn't run the workload!
no
And Peter's case (interrupted by signal):
$ while :; do perf record sleep 1; done
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.014 MB perf.data (~593 samples) ]
Reported-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/1399855645-25815-1-git-send-email-namhyung@kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
In the current version, when using perf record, if something goes
wrong in tools/perf/builtin-record.c:375
session = perf_session__new(file, false, NULL);
The error message:
"Not enough memory for reading per file header"
is issued. This error message seems to be outdated and is not very
helpful. This patch proposes to replace this error message by
"Perf session creation failed"
I believe this issue has been brought to lkml:
https://lkml.org/lkml/2014/2/24/458
although this patch only tackles a (small) part of the issue.
Additionnaly, this patch improves error reporting in
tools/perf/util/data.c open_file_write.
Currently, if the call to open fails, the user is unaware of it.
This patch logs the error, before returning the error code to
the caller.
Reported-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Adrien BAK <adrien.bak@metascale.org>
Link: http://lkml.kernel.org/r/1397786443.3093.4.camel@beast
[ Reorganize the changelog into paragraphs ]
[ Added empty line after fd declaration in open_file_write ]
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
