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To reduce perf-sys.h and eventually nuke it.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-ars2j5m3if3gypsvkbbijucq@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Remove traceevent/event-parse.h and traceevent/trace-seq.h from places
where it is not needed.
Should avoid rebuilding those files when these traceevent headers get
changed.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tzvetomir Stoyanov <tstoyanov@vmware.com>
Link: https://lkml.kernel.org/n/tip-26hn75jn9rdealn4uqtzend6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Display a warning when attempting to profile more than MAX_NR_CPU CPUs.
This patch should not change any behavior.
Signed-off-by: Kyle Meyer <kyle.meyer@hpe.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <russ.anderson@hpe.com>
Link: http://lore.kernel.org/lkml/20190827214352.94272-8-meyerk@stormcage.eag.rdlabs.hpecorp.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The function cpu__max_cpu() returns the possible number of CPUs as
defined in the sysfs and can be used as an alternative for MAX_NR_CPUS
in write_cache.
MAX_CACHES is replaced by cpu__max_cpu() * MAX_CACHE_LVL.
Signed-off-by: Kyle Meyer <kyle.meyer@hpe.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <russ.anderson@hpe.com>
Link: http://lore.kernel.org/lkml/20190827214352.94272-7-meyerk@stormcage.eag.rdlabs.hpecorp.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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nr_cpus, the number of CPUs online during a record session bound by
MAX_NR_CPUS, can be used as a dynamic alternative for MAX_NR_CPUS in
__machine__synthesize_threads and machine__set_current_tid.
Signed-off-by: Kyle Meyer <kyle.meyer@hpe.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <russ.anderson@hpe.com>
Link: http://lore.kernel.org/lkml/20190827214352.94272-6-meyerk@stormcage.eag.rdlabs.hpecorp.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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nr_cpus, the number of CPUs online during a record session bound by
MAX_NR_CPUS, can be used as a dynamic alternative for MAX_NR_CPUS in
perf_session__cpu_bitmap.
Signed-off-by: Kyle Meyer <kyle.meyer@hpe.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <russ.anderson@hpe.com>
Link: http://lore.kernel.org/lkml/20190827214352.94272-5-meyerk@stormcage.eag.rdlabs.hpecorp.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The function cpu__max_cpu() returns the possible number of CPUs as
defined in the sysfs and can be used as an alternative for MAX_NR_CPUS
in zero_per_pkg() and check_per_pkg().
Signed-off-by: Kyle Meyer <kyle.meyer@hpe.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <russ.anderson@hpe.com>
Link: http://lore.kernel.org/lkml/20190827214352.94272-4-meyerk@stormcage.eag.rdlabs.hpecorp.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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'nr_cpus', the number of CPUs online during a record session bound by
MAX_NR_CPUS, can be used as a dynamic alternative for MAX_NR_CPUS in
svg_build_topology_map().
The value of nr_cpus can be passed into str_to_bitmap(),
scan_core_topology(), and svg_build_topology_map() to replace
MAX_NR_CPUS as well.
Signed-off-by: Kyle Meyer <kyle.meyer@hpe.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <russ.anderson@hpe.com>
Link: http://lore.kernel.org/lkml/20190827214352.94272-3-meyerk@stormcage.eag.rdlabs.hpecorp.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Exchange the parameters of svg_build_topology_map() with 'struct
perf_env *env' and adjust the function accordingly.
This patch should not change any behavior, it is merely refactoring for
the following patch.
Committer notes:
No need to include env.h from svghelper.h, all it needs is a forward
declaration for 'struct perf_env', so move the include directive to
svghelper.c, where it is really needed.
Signed-off-by: Kyle Meyer <kyle.meyer@hpe.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <russ.anderson@hpe.com>
Link: http://lore.kernel.org/lkml/20190827214352.94272-2-meyerk@stormcage.eag.rdlabs.hpecorp.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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There's wrong bitmap considered when checking for cpu count of specific
node.
We do the needed computation for 'set' variable, but at the end we use
the 'c2c_he->cpuset' weight, which shows misleading numbers.
Fixes: 1e181b92a2da ("perf c2c report: Add 'node' sort key")
Reported-by: Joe Mario <jmario@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20190820140219.28338-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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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:
perf top:
Namhyung Kim:
- Decay all events in the evlist, we were decaying just the first event
in a group.
- Fix linking of histograms in different evsels in a event group with more
than two events.
With the two fixes above a command line such as:
# perf top -e '{cycles,instructions,cache-misses,cache-references}
Should work as expected, with four columns and with all of them being
decayed over time, i.e. less weight is given for older samples.
perf record:
Arnaldo Carvalho de Melo:
- Fix collection of build-ids when using setns() to get into namespaces,
which had been broken with the introduction of the extra thread to
react to PERF_RECORD_BPF_EVENT, i.e. to collect extra info for BPF
programs. We need to unshare(CLONE_FS) in that thread so that the
main one can do the setns(CLONE_NEWNS) when collectingthe build-ids.
Without that symbol resolution gets more difficult and potentially
misresolves symbols.
core:
Igor Lubashev:
- Further alignment in permission checking via capabilities to how the
kernel checks what tooling tries to do.
PowerPC:
Naveen N. Rao:
- Sync powerpc syscall.tbl, so that 'perf trace' gets the definitions
for recent syscalls.
libperf:
Jiri Olsa:
- Move the rest of the PERF_RECORD_ metadata struct definitions so that
we can use 'union perf_event'.
libtraceevent:
Steven Rostedt (VMware):
- Do not free tep->cmdlines in add_new_comm() on failure.
- Remove unneeded qsort and uses memmove instead
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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While reading a trace data file that had 100,000s of tasks, the process
took an extremely long time. I profiled it down to add_new_comm(), which
was doing a qsort() call on an array that was pretty much already sorted
(all but the last element. qsort() isn't very efficient when dealing
with mostly sorted arrays, and this definitely showed its issues.
When adding a new task to the task list, instead of using qsort(), do
another bsearch() with a function that will find the element before
where the new task will be inserted in. Then simply shift the rest of
the array, and insert the task where it belongs.
Fixes: f7d82350e597d ("tools/events: Add files to create libtraceevent.a")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: linux-trace-devel@vger.kernel.org
Link: http://lkml.kernel.org/r/20190828191820.127233764@goodmis.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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If the re-allocation of tep->cmdlines succeeds, then the previous
allocation of tep->cmdlines will be freed. If we later fail in
add_new_comm(), we must not free cmdlines, and also should assign
tep->cmdlines to the new allocation. Otherwise when freeing tep, the
tep->cmdlines will be pointing to garbage.
Fixes: a6d2a61ac653a ("tools lib traceevent: Remove some die() calls")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: linux-trace-devel@vger.kernel.org
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20190828191819.970121417@goodmis.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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When we started using a thread to catch the PERF_RECORD_BPF_EVENT meta
data events to then ask the kernel for further info (BTF, etc) for BPF
programs shortly after they get loaded, we forgot to use
unshare(CLONE_FS) as was done in:
868a832918f6 ("perf top: Support lookup of symbols in other mount namespaces.")
Do it so that we can enter the namespaces to read the build-ids at the
end of a 'perf record' session for the DSOs that had hits.
Before:
Starting a 'stress-ng --cpus 8' inside a container and then, outside the
container running:
# perf record -a --namespaces sleep 5
# perf buildid-list | grep stress-ng
#
We would end up with a 'perf.data' file that had no entry in its
build-id table for the /usr/bin/stress-ng binary inside the container
that got tons of PERF_RECORD_SAMPLEs.
After:
# perf buildid-list | grep stress-ng
f2ed02c68341183a124b9b0f6e2e6c493c465b29 /usr/bin/stress-ng
#
Then its just a matter of making sure that that binary debuginfo package
gets available in a place that 'perf report' will look at build-id keyed
ELF files, which, in my case, on a f30 notebook, was a matter of
installing the debuginfo file for the distro used in the container,
fedora 31:
# rpm -ivh http://fedora.c3sl.ufpr.br/linux/development/31/Everything/x86_64/debug/tree/Packages/s/stress-ng-debuginfo-0.07.29-10.fc31.x86_64.rpm
Then, because perf currently looks for those debuginfo files (richer ELF
symtab) inside that namespace (look at the setns calls):
openat(AT_FDCWD, "/proc/self/ns/mnt", O_RDONLY) = 137
openat(AT_FDCWD, "/proc/13169/ns/mnt", O_RDONLY) = 139
setns(139, CLONE_NEWNS) = 0
stat("/usr/bin/stress-ng", {st_mode=S_IFREG|0755, st_size=3065416, ...}) = 0
openat(AT_FDCWD, "/usr/bin/stress-ng", O_RDONLY) = 140
fcntl(140, F_GETFD) = 0
fstat(140, {st_mode=S_IFREG|0755, st_size=3065416, ...}) = 0
mmap(NULL, 3065416, PROT_READ, MAP_PRIVATE, 140, 0) = 0x7ff2fdc5b000
munmap(0x7ff2fdc5b000, 3065416) = 0
close(140) = 0
stat("stress-ng-0.07.29-10.fc31.x86_64.debug", 0x7fff45d71260) = -1 ENOENT (No such file or directory)
stat("/usr/bin/stress-ng-0.07.29-10.fc31.x86_64.debug", 0x7fff45d71260) = -1 ENOENT (No such file or directory)
stat("/usr/bin/.debug/stress-ng-0.07.29-10.fc31.x86_64.debug", 0x7fff45d71260) = -1 ENOENT (No such file or directory)
stat("/usr/lib/debug/usr/bin/stress-ng-0.07.29-10.fc31.x86_64.debug", 0x7fff45d71260) = -1 ENOENT (No such file or directory)
stat("/root/.debug/.build-id/f2/ed02c68341183a124b9b0f6e2e6c493c465b29", 0x7fff45d711e0) = -1 ENOENT (No such file or directory)
To only then go back to the "host" namespace to look just in the users's
~/.debug cache:
setns(137, CLONE_NEWNS) = 0
chdir("/root") = 0
close(137) = 0
close(139) = 0
stat("/root/.debug/.build-id/f2/ed02c68341183a124b9b0f6e2e6c493c465b29/elf", 0x7fff45d732e0) = -1 ENOENT (No such file or directory)
It continues to fail to resolve symbols:
# perf report | grep stress-ng | head -5
9.50% stress-ng-cpu stress-ng [.] 0x0000000000021ac1
8.58% stress-ng-cpu stress-ng [.] 0x0000000000021ab4
8.51% stress-ng-cpu stress-ng [.] 0x0000000000021489
7.17% stress-ng-cpu stress-ng [.] 0x00000000000219b6
3.93% stress-ng-cpu stress-ng [.] 0x0000000000021478
#
To overcome that we use:
# perf buildid-cache -v --add /usr/lib/debug/usr/bin/stress-ng-0.07.29-10.fc31.x86_64.debug
Adding f2ed02c68341183a124b9b0f6e2e6c493c465b29 /usr/lib/debug/usr/bin/stress-ng-0.07.29-10.fc31.x86_64.debug: Ok
#
# ls -la /root/.debug/.build-id/f2/ed02c68341183a124b9b0f6e2e6c493c465b29/elf
-rw-r--r--. 3 root root 2401184 Jul 27 07:03 /root/.debug/.build-id/f2/ed02c68341183a124b9b0f6e2e6c493c465b29/elf
# file /root/.debug/.build-id/f2/ed02c68341183a124b9b0f6e2e6c493c465b29/elf
/root/.debug/.build-id/f2/ed02c68341183a124b9b0f6e2e6c493c465b29/elf: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, interpreter \004, BuildID[sha1]=f2ed02c68341183a124b9b0f6e2e6c493c465b29, for GNU/Linux 3.2.0, with debug_info, not stripped, too many notes (256)
#
Now it finally works:
# perf report | grep stress-ng | head -5
23.59% stress-ng-cpu stress-ng [.] ackermann
23.33% stress-ng-cpu stress-ng [.] is_prime
17.36% stress-ng-cpu stress-ng [.] stress_cpu_sieve
6.08% stress-ng-cpu stress-ng [.] stress_cpu_correlate
3.55% stress-ng-cpu stress-ng [.] queens_try
#
I'll make sure that it looks for the build-id keyed files in both the
"host" namespace (the namespace the user running 'perf record' was a the
time of the recording) and in the container namespace, as it shouldn't
matter where a content based key lookup finds the ELF file to use in
resolving symbols, etc.
Reported-by: Karl Rister <krister@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Fixes: 657ee5531903 ("perf evlist: Introduce side band thread")
Link: https://lkml.kernel.org/n/tip-g79k0jz41adiaeuqud742t2l@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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So it's available for libperf's users.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-24-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Even more, to have a "perf_record_" prefix, so that they match the
PERF_RECORD_ enum they map to.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-23-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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So it's available for libperf's users.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-22-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Move the PERF_RECORD_COMPRESSED event definition to libperf's event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-21-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Move the PERF_RECORD_HEADER_FEATURE event definition to libperf's
event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-20-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Move the PERF_RECORD_TIME_CONV event definition to libperf's event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-19-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Move the PERF_RECORD_STAT_ROUND event definition to libperf's event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-18-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Move the PERF_RECORD_STAT event definition to libperf's event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-17-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Move the PERF_RECORD_STAT_CONFIG event definition to libperf's event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-16-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Move the PERF_RECORD_THREAD_MAP event definition to libperf's event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-15-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
Move the PERF_RECORD_SWITCH event definition to libperf's event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-14-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
perf/event.h
Move the PERF_RECORD_ITRACE_START event definition to libperf's event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-13-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
Move the PERF_RECORD_AUX event definition to libperf's event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-12-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
perf/event.h
Move the PERF_RECORD_AUXTRACE_ERROR event definition to libperf's
event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-11-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
Move the PERF_RECORD_AUXTRACE event definition to libperf's event.h.
Ipn order to keep libperf simple, we switch 'u64/u32/u16/u8'
types used events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-10-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
perf/event.h
Move the PERF_RECORD_AUXTRACE_INFO event definition to libperf's
event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-9-jolsa@kernel.org
[ Fix cs_etm__print_auxtrace_info() arg to be __u64 too to fix the CORESIGHT=1 build ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
Move the PERF_RECORD_ID_INDEX event definition to libperf's event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Add the PRI_ld64 define, so we can use it in printf output.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-8-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
Move the PERF_RECORD_HEADER_BUILD_ID event definition to libperf's event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8'
types used events to their generic '__u*' versions.
Adding the fix value for build_id variable, because it will never
change.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-7-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
perf/event.h
Move the PERF_RECORD_HEADER_TRACING_DATA event definition to libperf's event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8'
types used events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-6-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
perf/event.h
Move the PERF_RECORD_HEADER_EVENT_TYPE event definition to libperf's event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8'
types used events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-5-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
perf/event.h
Move the PERF_RECORD_EVENT_UPDATE event definition to libperf's event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8'
types used events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-4-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
Move the PERF_RECORD_CPU_MAP event definition to libperf's event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8'
types used events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-3-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
Move the PERF_RECORD_HEADER_ATTR event definition to libperf's event.h.
In order to keep libperf simple, we switch 'u64/u32/u16/u8' types used
events to their generic '__u*' versions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190828135717.7245-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
The event group feature links relevant hist entries among events so that
they can be displayed together. During the link process, each hist
entry in non-leader events is connected to a hist entry in the leader
event. This is done in order of events specified in the command line so
it assumes that events are linked in the order.
But 'perf top' can break the assumption since it does the link process
multiple times. For example, a hist entry can be in the third event
only at first so it's linked after the leader. Some time later, second
event has a hist entry for it and it'll be linked after the entry of the
third event.
This makes the code compilicated to deal with such unordered entries.
This patch simply unlink all the entries after it's printed so that they
can assume the correct order after the repeated link process. Also it'd
be easy to deal with decaying old entries IMHO.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20190827231555.121411-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
Currently perf top only decays entries in a selected evsel. I don't
know whether it's intended (maybe due to performance reason?) but anyway
it might show incorrect output when event group is used since users will
see leader event is decayed but others are not.
This patch moves the decay code into perf_top__resort_hists() so that
stdio and TUI code shared the logic.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20190827231555.121411-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
It was put in place just to make sure the 'new' C++ operator wouldn't
clash with some argument name in util.h, but there is not anymore any
such argument and also the reason stated for util.h to be included there
was to get the __maybe_unused definition, that is in linux/compiler.h,
so use that instead and nuke util-cxx.h.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-1r5tvfnwiydjxhukgqs6bi11@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
There is no need for that util/util.h include there and, remove it,
pruning the include tree, fix the fallout by adding necessary headers to
places that were getting needed includes indirectly from evlist.h ->
util.h.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-s9f7uve8wvykr5itcm7m7d8q@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
And fix up places where util.h is needed but was obtained indirectly via
builtin.h.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-a01ig3c4t76ye5wkqmtgk9qn@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
Warn that /proc/sys/kernel/perf_event_paranoid can also restrict kernel
symbols.
Signed-off-by: Igor Lubashev <ilubashe@akamai.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1566869956-7154-6-git-send-email-ilubashe@akamai.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
The kernel is using CAP_SYSLOG capability instead of uid==0 and euid==0
when checking kptr_restrict. Make perf do the same.
Also, the kernel is a more restrictive than "no restrictions" in case of
kptr_restrict==0, so add the same logic to perf.
Signed-off-by: Igor Lubashev <ilubashe@akamai.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1566869956-7154-5-git-send-email-ilubashe@akamai.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
Perf was too restrictive about sysctl kernel.perf_event_paranoid. The
kernel only disallows profiling when perf_event_paranoid > 1. Make perf
do the same.
Committer testing:
For a non-root user:
$ id
uid=1000(acme) gid=1000(acme) groups=1000(acme),10(wheel) context=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
$
Before:
We were restricting it to just userspace (:u suffix) even for a
workload started by the user:
$ perf record sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.001 MB perf.data (8 samples) ]
$ perf evlist
cycles:u
$ perf evlist -v
cycles:u: size: 112, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|PERIOD, read_format: ID, disabled: 1, inherit: 1, exclude_kernel: 1, mmap: 1, comm: 1, freq: 1, enable_on_exec: 1, task: 1, precise_ip: 3, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, ksymbol: 1, bpf_event: 1
$ perf report --stdio
# To display the perf.data header info, please use --header/--header-only options.
#
# Total Lost Samples: 0
#
# Samples: 8 of event 'cycles:u'
# Event count (approx.): 1040396
#
# Overhead Command Shared Object Symbol
# ........ ....... ................ ......................
#
68.36% sleep libc-2.29.so [.] _dl_addr
27.33% sleep ld-2.29.so [.] dl_main
3.80% sleep ld-2.29.so [.] _dl_setup_hash
#
# (Tip: Order by the overhead of source file name and line number: perf report -s srcline)
#
$
$
After:
When the kernel allows profiling the kernel in that scenario:
$ perf record sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.023 MB perf.data (11 samples) ]
$ perf evlist
cycles
$ perf evlist -v
cycles: size: 112, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|PERIOD, read_format: ID, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, enable_on_exec: 1, task: 1, precise_ip: 3, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, ksymbol: 1, bpf_event: 1
$
$ perf report --stdio
# To display the perf.data header info, please use --header/--header-only options.
#
# Total Lost Samples: 0
#
# Samples: 11 of event 'cycles'
# Event count (approx.): 1601964
#
# Overhead Command Shared Object Symbol
# ........ ....... ................ ..........................
#
28.14% sleep [kernel.vmlinux] [k] __rb_erase_color
27.21% sleep [kernel.vmlinux] [k] unmap_page_range
27.20% sleep ld-2.29.so [.] __tunable_get_val
15.24% sleep [kernel.vmlinux] [k] thp_get_unmapped_area
1.96% perf [kernel.vmlinux] [k] perf_event_exec
0.22% perf [kernel.vmlinux] [k] native_sched_clock
0.02% perf [kernel.vmlinux] [k] intel_bts_enable_local
0.00% perf [kernel.vmlinux] [k] native_write_msr
#
# (Tip: Boolean options have negative forms, e.g.: perf report --no-children)
#
$
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Igor Lubashev <ilubashe@akamai.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1566869956-7154-4-git-send-email-ilubashe@akamai.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
The kernel is using CAP_SYS_ADMIN instead of euid==0 to override
perf_event_paranoid check. Make perf do the same.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> # coresight part
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1566869956-7154-3-git-send-email-ilubashe@akamai.com
Signed-off-by: Igor Lubashev <ilubashe@akamai.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
Check for ref_reloc_sym before using it instead of checking
symbol_conf.kptr_restrict and relying solely on that check.
Reported-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Igor Lubashev <ilubashe@akamai.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1566869956-7154-2-git-send-email-ilubashe@akamai.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
Copy over powerpc syscall.tbl to grab changes from the below commits:
commit cee3536d24a1 ("powerpc: Wire up clone3 syscall")
commit 1a271a68e030 ("arch: mark syscall number 435 reserved for clone3")
commit 7615d9e1780e ("arch: wire-up pidfd_open()")
commit d8076bdb56af ("uapi: Wire up the mount API syscalls on non-x86 arches [ver #2]")
commit 39036cd27273 ("arch: add pidfd and io_uring syscalls everywhere")
commit 48166e6ea47d ("y2038: add 64-bit time_t syscalls to all 32-bit architectures")
commit d33c577cccd0 ("y2038: rename old time and utime syscalls")
commit 00bf25d693e7 ("y2038: use time32 syscall names on 32-bit")
commit 8dabe7245bbc ("y2038: syscalls: rename y2038 compat syscalls")
commit 0d6040d46817 ("arch: add split IPC system calls where needed")
Reported-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/20190827071458.19897-1-naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
|
If PEBS declares ability to output its data to Intel PT stream, use the
aux_output attribute bit to enable PEBS data output to PT. This requires
a PT event to be present and scheduled in the same context. Unlike the
DS area, the kernel does not extract PEBS records from the PT stream to
generate corresponding records in the perf stream, because that would
require real time in-kernel PT decoding, which is not feasible. The PMI,
however, can still be used.
The output setting is per-CPU, so all PEBS events must be either writing
to PT or to the DS area, therefore, in case of conflict, the conflicting
event will fail to schedule, allowing the rotation logic to alternate
between the PEBS->PT and PEBS->DS events.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: kan.liang@linux.intel.com
Link: https://lkml.kernel.org/r/20190806084606.4021-3-alexander.shishkin@linux.intel.com
|
|
In some cases, ordinary (non-AUX) events can generate data for AUX events.
For example, PEBS events can come out as records in the Intel PT stream
instead of their usual DS records, if configured to do so.
One requirement for such events is to consistently schedule together, to
ensure that the data from the "AUX output" events isn't lost while their
corresponding AUX event is not scheduled. We use grouping to provide this
guarantee: an "AUX output" event can be added to a group where an AUX event
is a group leader, and provided that the former supports writing to the
latter.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: kan.liang@linux.intel.com
Link: https://lkml.kernel.org/r/20190806084606.4021-2-alexander.shishkin@linux.intel.com
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