Introduce a new option to record PERF_RECORD_NAMESPACES events emitted
by the kernel when fork, clone, setns or unshare are invoked. And update
perf-record documentation with the new option to record namespace
events.
Committer notes:
Combined it with a later patch to allow printing it via 'perf report -D'
and be able to test the feature introduced in this patch. Had to move
here also perf_ns__name(), that was introduced in another later patch.
Also used PRIu64 and PRIx64 to fix the build in some enfironments wrt:
util/event.c:1129:39: error: format '%lx' expects argument of type 'long unsigned int', but argument 6 has type 'long long unsigned int' [-Werror=format=]
ret += fprintf(fp, "%u/%s: %lu/0x%lx%s", idx
^
Testing it:
# perf record --namespaces -a
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 1.083 MB perf.data (423 samples) ]
#
# perf report -D
<SNIP>
3 2028902078892 0x115140 [0xa0]: PERF_RECORD_NAMESPACES 14783/14783 - nr_namespaces: 7
[0/net: 3/0xf0000081, 1/uts: 3/0xeffffffe, 2/ipc: 3/0xefffffff, 3/pid: 3/0xeffffffc,
4/user: 3/0xeffffffd, 5/mnt: 3/0xf0000000, 6/cgroup: 3/0xeffffffb]
0x1151e0 [0x30]: event: 9
.
. ... raw event: size 48 bytes
. 0000: 09 00 00 00 02 00 30 00 c4 71 82 68 0c 7f 00 00 ......0..q.h....
. 0010: a9 39 00 00 a9 39 00 00 94 28 fe 63 d8 01 00 00 .9...9...(.c....
. 0020: 03 00 00 00 00 00 00 00 ce c4 02 00 00 00 00 00 ................
<SNIP>
NAMESPACES events: 1
<SNIP>
#
Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Aravinda Prasad <aravinda@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sargun Dhillon <sargun@sargun.me>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/148891930386.25309.18412039920746995488.stgit@hbathini.in.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
As this is a GNU extension and while harmless in this case, we can do
the same thing in a more clearer way by using a existing thread_map and
cpu_map constructors:
With this we avoid this while compiling with clang:
util/evsel.c:1659:17: error: field 'map' with variable sized type 'struct cpu_map' not at the end of a struct or class is a GNU extension
[-Werror,-Wgnu-variable-sized-type-not-at-end]
struct cpu_map map;
^
util/evsel.c:1667:20: error: field 'map' with variable sized type 'struct thread_map' not at the end of a struct or class is a GNU extension
[-Werror,-Wgnu-variable-sized-type-not-at-end]
struct thread_map map;
^
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-207juvrqjiar7uvas2s83v5i@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When a tool can't open counters due to the kernel.perf_event_paranoit
sysctl setting, we inform how to tweak it to allow the operation to
succeed, in addition to that, suggest setting /etc/sysctl.conf to
make the setting permanent.
Suggested-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-4gwe99k4a6p12d4u8bbyttj2@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding perf_evsel::ignore_missing_cpu_thread bool.
When set true, it allows perf to ignore error of missing pid of perf
event syscall.
We remove missing thread id from the thread_map, so the rest of the
processing like ioctl and mmap won't get disturbed with -1 fd.
The reason for supporting this is to ease up monitoring group of pids,
that 'disappear' before perf opens their event. This currently leads
perf to report error and exit and makes perf record's -u option unusable
under certain setup.
With this change we will allow this race and ignore such failure with
following warning:
WARNING: Ignored open failure for pid 8605
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20161213074622.GA3084@krava
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It's more readable and will ease up following patches.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1481538943-21874-3-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It is useful for debug to see file descriptors for each event.
Before:
$ perf stat -vvv -e cycles,cache-misses ls
...
sys_perf_event_open: pid 12146 cpu -1 group_fd -1 flags 0x8
...
sys_perf_event_open: pid 12146 cpu -1 group_fd 3 flags 0x8
sys_perf_event_open failed, error -13
Now:
$ perf stat -vvv -e cycles,cache-misses ls
...
sys_perf_event_open: pid 12858 cpu -1 group_fd -1 flags 0x8 = 3
...
sys_perf_event_open: pid 12858 cpu -1 group_fd 3 flags 0x8
sys_perf_event_open failed, error -13
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Joe Mario <jmario@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1479764011-10732-2-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It can be useful to specify branch type state per event, for example if
we want to collect both software trace points and last branch PMU events
in a single collection. Currently this doesn't work because the software
trace point errors out with -b.
There was already a branch-type parameter to configure branch sample
types per event in the parser, but it was stubbed out. This patch
implements the necessary plumbing to actually enable it.
Now:
$ perf record -e sched:sched_switch,cpu/cpu-cycles,branch_type=any/ ...
works.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1476306127-19721-1-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Experimenting a bit using cppcheck[1], a static checker brought to my
attention by Colin, reducing the scope of some variables, reducing the
line of source code lines in the process:
$ cppcheck --enable=style tools/perf/util/thread.c
Checking tools/perf/util/thread.c...
[tools/perf/util/thread.c:17]: (style) The scope of the variable 'leader' can be reduced.
[tools/perf/util/thread.c:133]: (style) The scope of the variable 'err' can be reduced.
[tools/perf/util/thread.c:273]: (style) The scope of the variable 'err' can be reduced.
Will continue later, but these are already useful, keep them.
1: https://sourceforge.net/p/cppcheck/wiki/Home/
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-ixws7lbycihhpmq9cc949ti6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch makes it possible to use the current filter framework with
address filters. That way address filters for HW tracers such as
CoreSight and Intel PT can be communicated to the kernel drivers.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1474037045-31730-4-git-send-email-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Making function perf_evsel__append_filter() static and introducing a new
tracepoint specific function to append filters. That way we eliminate
redundant code and avoid formatting mistake.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1474037045-31730-3-git-send-email-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
By making function perf_evsel__append_filter() take a format rather than
an operator it is possible to reuse the code for other purposes (ex.
Intel PT and CoreSight) than tracepoints.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1474037045-31730-2-git-send-email-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Removing superfluous initialization of weight, it's already set to 0 via
memset.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Joe Mario <jmario@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1474290610-23241-3-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We have to check if the values are >= *_MAX, not just >, fix it.
From the bugzilla report:
''In file /tools/perf/util/evsel.c function __perf_evsel__hw_cache_name
it appears that there is a bug that reads beyond the end of the buffer.
The statement "if (type > PERF_COUNT_HW_CACHE_MAX)" allows type to be
equal to the maximum value. Later, when statement "if
(!perf_evsel__is_cache_op_valid(type, op))" is executed, the function
can access array perf_evsel__hw_cache_stat[type] beyond the end of the
buffer.
It appears to me that the statement "if (type > PERF_COUNT_HW_CACHE_MAX)"
should be "if (type >= PERF_COUNT_HW_CACHE_MAX)"
Bug found with Coverity and manual code review. No attempts were made to
execute the code with a maximum type value.''
Committer note:
Testing it:
$ perf record -e $(echo $(perf list cache | cut -d \[ -f1) | sed 's/ /,/g') usleep 1
[ perf record: Woken up 16 times to write data ]
[ perf record: Captured and wrote 0.023 MB perf.data (34 samples) ]
$ perf evlist
L1-dcache-load-misses
L1-dcache-loads
L1-dcache-stores
L1-icache-load-misses
LLC-load-misses
LLC-loads
LLC-store-misses
LLC-stores
branch-load-misses
branch-loads
dTLB-load-misses
dTLB-loads
dTLB-store-misses
dTLB-stores
iTLB-load-misses
iTLB-loads
node-load-misses
node-loads
node-store-misses
node-stores
$ perf list cache
List of pre-defined events (to be used in -e):
L1-dcache-load-misses [Hardware cache event]
L1-dcache-loads [Hardware cache event]
L1-dcache-stores [Hardware cache event]
L1-icache-load-misses [Hardware cache event]
LLC-load-misses [Hardware cache event]
LLC-loads [Hardware cache event]
LLC-store-misses [Hardware cache event]
LLC-stores [Hardware cache event]
branch-load-misses [Hardware cache event]
branch-loads [Hardware cache event]
dTLB-load-misses [Hardware cache event]
dTLB-loads [Hardware cache event]
dTLB-store-misses [Hardware cache event]
dTLB-stores [Hardware cache event]
iTLB-load-misses [Hardware cache event]
iTLB-loads [Hardware cache event]
node-load-misses [Hardware cache event]
node-loads [Hardware cache event]
node-store-misses [Hardware cache event]
node-stores [Hardware cache event]
$
Reported-by: Brian Sweeney <bsweeney@lgsinnovations.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=153351
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding --sample-cpu option to be able to explicitly enable CPU sample
type. Currently it's only enable implicitly in case the target is cpu
related.
It will be useful for following c2c record tool.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1470074555-24889-8-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
That is the default used when no events is specified in tools, separate
it so that simpler tools that need no evlist can use it directly.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-67mwuthscwroz88x9pswcqyv@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch allows following config terms and option:
Globally setting events to overwrite;
# perf record --overwrite ...
Set specific events to be overwrite or no-overwrite.
# perf record --event cycles/overwrite/ ...
# perf record --event cycles/no-overwrite/ ...
Add missing config terms and update the config term array size because
the longest string length has changed.
For overwritable events, it automatically selects attr.write_backward
since perf requires it to be backward for reading.
Test result:
# perf record --overwrite -e syscalls:*enter_nanosleep* usleep 1
[ perf record: Woken up 2 times to write data ]
[ perf record: Captured and wrote 0.011 MB perf.data (1 samples) ]
# perf evlist -v
syscalls:sys_enter_nanosleep: type: 2, size: 112, config: 0x134, { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|CPU|PERIOD|RAW, disabled: 1, inherit: 1, mmap: 1, comm: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, write_backward: 1
# Tip: use 'perf evlist --trace-fields' to show fields for tracepoint events
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1468485287-33422-14-git-send-email-wangnan0@huawei.com
Signed-off-by: He Kuang <hekuang@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
evsel->overwrite indicator means an event should be put into
overwritable ring buffer. In current implementation, it equals to
evsel->attr.write_backward. To reduce compliexity, remove
evsel->overwrite, use evsel->attr.write_backward instead.
In addition, in __perf_evsel__open(), if kernel doesn't support
write_backward and user explicitly set it in evsel, don't fallback
like other missing feature, since it is meaningless to fall back to
a forward ring buffer in this case: we are unable to stably read
from an forward overwritable ring buffer.
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1468485287-33422-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
So that we don't have to carry a string.h header in evsel.h
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-2lwpm2aytdvvgo626zuat6et@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The tools so far have been using the strerror_r() GNU variant, that
returns a string, be it the buffer passed or something else.
But that, besides being tricky in cases where we expect that the
function using strerror_r() returns the error formatted in a provided
buffer (we have to check if it returned something else and copy that
instead), breaks the build on systems not using glibc, like Alpine
Linux, where musl libc is used.
So, introduce yet another wrapper, str_error_r(), that has the GNU
interface, but uses the portable XSI variant of strerror_r(), so that
users rest asured that the provided buffer is used and it is what is
returned.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-d4t42fnf48ytlk8rjxs822tf@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add Utility function to fetch arch using evsel. (evsel->env->arch)
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Blanchard <anton@ozlabs.org>
Cc: Daniel Axtens <dja@axtens.net>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1467267262-4589-2-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit b90dc17a5d "perf evsel: Add overwrite attribute and check
write_backward" misunderstood the 'order' should be obeyed in
__perf_evsel__open.
But the way this was done for attr.write_backwards was buggy, as we need
to check features in the inverse order of their introduction to the
kernel, so that a newer tool checks first the newest perf_event_attr
fields, detecting that the older kernel doesn't have support for them.
Also, we can avoid calling sys_perf_event_open() if we have already
detected the missing of write_backward.
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Fixes: b90dc17a5d ("perf evsel: Add overwrite attribute and check write_backward")
Link: http://lkml.kernel.org/r/1466419645-75551-2-git-send-email-wangnan0@huawei.com
Link: http://lkml.kernel.org/r/20160616214724.GI13337@kernel.org
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
User visible:
- Tooling support for TopDown counters, recently added to the kernel (Andi Kleen)
- Show call graphs in 'perf script' when 1st event doesn't have it but some other has (He Kuang)
- Fix terminal cleanup when handling invalid .perfconfig files in 'perf top' (Taeung Song)
Build fixes:
- Respect CROSS_COMPILE for the linker in libapi (Lucas Stach)
Infrastructure:
- Fix perf_evlist__alloc_mmap() failure path (Wang Nan)
- Provide way to extract integer value from format_field (Arnaldo Carvalho de Melo)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo-20160606' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
User visible changes:
- Tooling support for TopDown counters, recently added to the kernel (Andi Kleen)
- Show call graphs in 'perf script' when 1st event doesn't have it but some other has (He Kuang)
- Fix terminal cleanup when handling invalid .perfconfig files in 'perf top' (Taeung Song)
Build fixes:
- Respect CROSS_COMPILE for the linker in libapi (Lucas Stach)
Infrastructure changes:
- Fix perf_evlist__alloc_mmap() failure path (Wang Nan)
- Provide way to extract integer value from format_field (Arnaldo Carvalho de Melo)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Out of perf_evsel__intval(), that requires passing the variable name,
that will then be searched in the list of tracepoint variables for the
given evsel.
In cases such as syscall file descriptor ("fd") tracking, this is
wasteful, we need just to use perf_evsel__field() and cache the
format_field.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-r6f89jx9j5nkx037d0naviqy@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This allows (with a previous change to the perf error return ABI) for
calling out in userspace the exact reason for perf record failing
when PMU doesn't support overflow interrupts.
Note that this needs to be put ahead of existing precise_ip check as
that gets hit otherwise for the sampling fail case as well.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <acme@redhat.com>
Cc: <linux-snps-arc@lists.infradead.org>
Cc: <vincent.weaver@maine.edu>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Link: http://lkml.kernel.org/r/1462786660-2900-2-git-send-email-vgupta@synopsys.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull perf updates from Ingo Molnar:
"Mostly tooling and PMU driver fixes, but also a number of late updates
such as the reworking of the call-chain size limiting logic to make
call-graph recording more robust, plus tooling side changes for the
new 'backwards ring-buffer' extension to the perf ring-buffer"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits)
perf record: Read from backward ring buffer
perf record: Rename variable to make code clear
perf record: Prevent reading invalid data in record__mmap_read
perf evlist: Add API to pause/resume
perf trace: Use the ptr->name beautifier as default for "filename" args
perf trace: Use the fd->name beautifier as default for "fd" args
perf report: Add srcline_from/to branch sort keys
perf evsel: Record fd into perf_mmap
perf evsel: Add overwrite attribute and check write_backward
perf tools: Set buildid dir under symfs when --symfs is provided
perf trace: Only auto set call-graph to "dwarf" when syscalls are being traced
perf annotate: Sort list of recognised instructions
perf annotate: Fix identification of ARM blt and bls instructions
perf tools: Fix usage of max_stack sysctl
perf callchain: Stop validating callchains by the max_stack sysctl
perf trace: Fix exit_group() formatting
perf top: Use machine->kptr_restrict_warned
perf trace: Warn when trying to resolve kernel addresses with kptr_restrict=1
perf machine: Do not bail out if not managing to read ref reloc symbol
perf/x86/intel/p4: Trival indentation fix, remove space
...
Add 'overwrite' attribute to evsel to mark whether this event is
overwritable. The following commits will support syntax like:
# perf record -e cycles/overwrite/ ...
An overwritable evsel requires kernel support for the
perf_event_attr.write_backward ring buffer feature.
Add it to perf_missing_feature.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1463762315-155689-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull perf updates from Ingo Molnar:
"Bigger kernel side changes:
- Add backwards writing capability to the perf ring-buffer code,
which is preparation for future advanced features like robust
'overwrite support' and snapshot mode. (Wang Nan)
- Add pause and resume ioctls for the perf ringbuffer (Wang Nan)
- x86 Intel cstate code cleanups and reorgnization (Thomas Gleixner)
- x86 Intel uncore and CPU PMU driver updates (Kan Liang, Peter
Zijlstra)
- x86 AUX (Intel PT) related enhancements and updates (Alexander
Shishkin)
- x86 MSR PMU driver enhancements and updates (Huang Rui)
- ... and lots of other changes spread out over 40+ commits.
Biggest tooling side changes:
- 'perf trace' features and enhancements. (Arnaldo Carvalho de Melo)
- BPF tooling updates (Wang Nan)
- 'perf sched' updates (Jiri Olsa)
- 'perf probe' updates (Masami Hiramatsu)
- ... plus 200+ other enhancements, fixes and cleanups to tools/
The merge commits, the shortlog and the changelogs contain a lot more
details"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (249 commits)
perf/core: Disable the event on a truncated AUX record
perf/x86/intel/pt: Generate PMI in the STOP region as well
perf buildid-cache: Use lsdir() for looking up buildid caches
perf symbols: Use lsdir() for the search in kcore cache directory
perf tools: Use SBUILD_ID_SIZE where applicable
perf tools: Fix lsdir to set errno correctly
perf trace: Move seccomp args beautifiers to tools/perf/trace/beauty/
perf trace: Move flock op beautifier to tools/perf/trace/beauty/
perf build: Add build-test for debug-frame on arm/arm64
perf build: Add build-test for libunwind cross-platforms support
perf script: Fix export of callchains with recursion in db-export
perf script: Fix callchain addresses in db-export
perf script: Fix symbol insertion behavior in db-export
perf symbols: Add dso__insert_symbol function
perf scripting python: Use Py_FatalError instead of die()
perf tools: Remove xrealloc and ALLOC_GROW
perf help: Do not use ALLOC_GROW in add_cmd_list
perf pmu: Make pmu_formats_string to check return value of strbuf
perf header: Make topology checkers to check return value of strbuf
perf tools: Make alias handler to check return value of strbuf
...
Now with the default for the kernel.perf_event_paranoid sysctl being 2 [1]
we need to fall back to :u, i.e. to set perf_event_attr.exclude_kernel
to 1.
Before:
[acme@jouet linux]$ perf record usleep 1
Error:
You may not have permission to collect stats.
Consider tweaking /proc/sys/kernel/perf_event_paranoid,
which controls use of the performance events system by
unprivileged users (without CAP_SYS_ADMIN).
The current value is 2:
-1: Allow use of (almost) all events by all users
>= 0: Disallow raw tracepoint access by users without CAP_IOC_LOCK
>= 1: Disallow CPU event access by users without CAP_SYS_ADMIN
>= 2: Disallow kernel profiling by users without CAP_SYS_ADMIN
[acme@jouet linux]$
After:
[acme@jouet linux]$ perf record usleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.016 MB perf.data (7 samples) ]
[acme@jouet linux]$ perf evlist
cycles:u
[acme@jouet linux]$ perf evlist -v
cycles:u: size: 112, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|PERIOD, disabled: 1, inherit: 1, exclude_kernel: 1, mmap: 1, comm: 1, freq: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1
[acme@jouet linux]$
And if the user turns on verbose mode, an explanation will appear:
[acme@jouet linux]$ perf record -v usleep 1
Warning:
kernel.perf_event_paranoid=2, trying to fall back to excluding kernel samples
mmap size 528384B
[ perf record: Woken up 1 times to write data ]
Looking at the vmlinux_path (8 entries long)
Using /lib/modules/4.6.0-rc7+/build/vmlinux for symbols
[ perf record: Captured and wrote 0.016 MB perf.data (7 samples) ]
[acme@jouet linux]$
[1] 0161028b7c ("perf/core: Change the default paranoia level to 2")
Reported-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-b20jmx4dxt5hpaa9t2rroi0o@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We were showing a hardcoded default value for the kernel.perf_event_paranoid
sysctl, now that it became more paranoid (1 -> 2 [1]), this would need to be
updated, instead show the current value:
[acme@jouet linux]$ perf record ls
Error:
You may not have permission to collect stats.
Consider tweaking /proc/sys/kernel/perf_event_paranoid,
which controls use of the performance events system by
unprivileged users (without CAP_SYS_ADMIN).
The current value is 2:
-1: Allow use of (almost) all events by all users
>= 0: Disallow raw tracepoint access by users without CAP_IOC_LOCK
>= 1: Disallow CPU event access by users without CAP_SYS_ADMIN
>= 2: Disallow kernel profiling by users without CAP_SYS_ADMIN
[acme@jouet linux]$
[1] 0161028b7c ("perf/core: Change the default paranoia level to 2")
Reported-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-0gc4rdpg8d025r5not8s8028@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Now we can see if it is set when using verbose mode in various tools,
such as 'perf test':
# perf test -vv back
45: Test backward reading from ring buffer :
--- start ---
<SNIP>
------------------------------------------------------------
perf_event_attr:
type 2
size 112
config 0x98
{ sample_period, sample_freq } 1
sample_type IP|TID|TIME|CPU|PERIOD|RAW
disabled 1
mmap 1
comm 1
task 1
sample_id_all 1
exclude_guest 1
mmap2 1
comm_exec 1
write_backward 1
------------------------------------------------------------
sys_perf_event_open: pid 20911 cpu -1 group_fd -1 flags 0x8
<SNIP>
---- end ----
Test backward reading from ring buffer: Ok
#
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-kxv05kv9qwl5of7rzfeiiwbv@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The error messages returned by this method should not have an ending
newline, fix the two cases where it was.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-8af0pazzhzl3dluuh8p7ar7p@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When the kernel allows tweaking perf_event_max_stack and the event being
setup has PERF_SAMPLE_CALLCHAIN in its perf_event_attr.sample_type, tell
the user that tweaking /proc/sys/kernel/perf_event_max_stack may solve
the problem.
Before:
# echo 32000 > /proc/sys/kernel/perf_event_max_stack
# perf record -g usleep 1
Error:
The sys_perf_event_open() syscall returned with 12 (Cannot allocate memory) for event (cycles:ppp).
/bin/dmesg may provide additional information.
No CONFIG_PERF_EVENTS=y kernel support configured?
#
After:
# echo 64000 > /proc/sys/kernel/perf_event_max_stack
# perf record -g usleep 1
Error:
Not enough memory to setup event with callchain.
Hint: Try tweaking /proc/sys/kernel/perf_event_max_stack
Hint: Current value: 64000
#
Suggested-by: David Ahern <dsahern@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-ebv0orelj1s1ye857vhb82ov@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
They still use functions that would drag more stuff to the python
binding, where these fprintf methods are not used, so separate it.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-xfp0mgq3hh3px61di6ixi1jk@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Not used at all, nuke it.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-jf2w8ce8nl3wso3vuodg5jci@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This way the print routine merely does printing, not requiring access to
the resolving machinery, which helps disentangling the object files and
easing creating subsets with a limited functionality set.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-2ti2jbra8fypdfawwwm3aee3@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
# perf test -v python
16: Try 'import perf' in python, checking link problems :
--- start ---
test child forked, pid 672
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: /tmp/build/perf/python/perf.so: undefined symbol:
symbol_conf
test child finished with -1
---- end ----
Try 'import perf' in python, checking link problems: FAILED!
#
To fix it just pass a parameter to perf_evsel__fprintf_sym telling if
callchains should be printed.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-comrsr20bsnr8bg0n6rfwv12@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The recent perf_evsel__fprintf_callchain() move to evsel.c added several
new symbol requirements to the python binding, for instance:
# perf test -v python
16: Try 'import perf' in python, checking link problems :
--- start ---
test child forked, pid 18030
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: /tmp/build/perf/python/perf.so: undefined symbol:
callchain_cursor
test child finished with -1
---- end ----
Try 'import perf' in python, checking link problems: FAILED!
#
This would require linking against callchain.c to access to the global
callchain_cursor variables.
Since lots of functions already receive as a parameter a
callchain_cursor struct pointer, make that be the case for some more
function so that we can start phasing out usage of yet another global
variable.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-djko3097eyg2rn66v2qcqfvn@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Those were converted to be evsel methods long ago, move the
source to where it belongs.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-vja8rjmkw3gd5ungaeyb5s2j@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The rename is for consistency with the parameter name.
Make it public for fine grained control of which evsels should have
callchains enabled, like, for instance, will be done in the next
changesets in 'perf trace', to enable callchains just on the
"raw_syscalls:sys_exit" tracepoint.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-og8vup111rn357g4yagus3ao@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Instead receive a callchain_param pointer to configure callchain
aspects, not doing so if NULL is passed.
This will allow fine grained control over which evsels in an evlist
gets callchains enabled.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-2mupip6khc92mh5x4nw9to82@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To avoid parsing event->header.misc in many locations.
This will also allow setting perf.sample.{ip,cpumode} in a single place,
from tracepoint fields, as needed by 'perf kvm' with PPC guests, where
the guest hardware counters is not available at the host.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-qp3yradhyt6q3wl895b1aat0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Allow user to easily switch all events to user or kernel space with simple
--all-user or --all-kernel options.
This will be handy within perf mem/c2c wrappers to switch easily monitoring
modes.
Committer note:
Testing it:
# perf record --all-kernel --all-user -a sleep 2
Error: option `all-user' cannot be used with all-kernel
Usage: perf record [<options>] [<command>]
or: perf record [<options>] -- <command> [<options>]
--all-user Configure all used events to run in user space.
--all-kernel Configure all used events to run in kernel space.
# perf record --all-user --all-kernel -a sleep 2
Error: option `all-kernel' cannot be used with all-user
Usage: perf record [<options>] [<command>]
or: perf record [<options>] -- <command> [<options>]
--all-kernel Configure all used events to run in kernel space.
--all-user Configure all used events to run in user space.
# perf record --all-user -a sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 1.416 MB perf.data (162 samples) ]
# perf report | grep '\[k\]'
# perf record --all-kernel -a sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 1.423 MB perf.data (296 samples) ]
# perf report | grep '\[\.\]'
#
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1455525293-8671-2-git-send-email-jolsa@kernel.org
[ Made those options to be mutually exclusive ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf_event_paranoid was only documented in source code and a perf error
message. Copy the documentation from the error message to
Documentation/sysctl/kernel.txt.
perf_cpu_time_max_percent was already documented but missing from the
list at the top, so add it there.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-doc@vger.kernel.org
Link: http://lkml.kernel.org/r/20160119213515.GG2637@decadent.org.uk
[ Remove reference to external Documentation file, provide info inline, as before ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
