Ingo Molnar [Fri, 29 Apr 2016 19:37:40 +0000 (21:37 +0200)]
Merge tag 'perf-core-for-mingo-
20160429' of git://git./linux/kernel/git/acme/linux into perf/core
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
User visible changes:
- Allow generate timestamped suffixed multiple perf.data files upon receiving
SIGUSR2 in 'perf record', to slice a long running monitoring session, allowing
to dump uninteresting sessions (Wang Nan)
- Handle ENOMEM for perf_event_max_stack + PERF_SAMPLE_CALLCHAIN
in perf_evsel__open_strerror(), showing a more informative
message when the request call stack depth can't be allocated by
the kernel (Arnaldo Carvalho de Melo)
Infrastructure changes:
- Use strbuf for making strings in 'perf probe' (Masami Hiramatsu)
- Do not use sizeof on pointer type, not a problem since its a pointer to
pointer, fix none the less. Found by Coccinelle (Vaishali Thakkar)
Cleanups:
- Fix for Coverity found issues in the bpf feature build test (Florian Fainelli)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Vaishali Thakkar [Thu, 28 Apr 2016 16:46:57 +0000 (22:16 +0530)]
perf tests: Do not use sizeof on pointer type
Using sizeof on a malloced pointer type will return the wordsize which
can often cause one to allocate a buffer much smaller than it is needed.
So, here do not use sizeof on pointer type.
Note that this has no effect on runtime because 'dsos' is a pointer to a
pointer.
Problem found using Coccinelle.
Signed-off-by: Vaishali Thakkar <vaishali.thakkar@oracle.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1461862017-23358-1-git-send-email-vaishali.thakkar@oracle.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Wed, 27 Apr 2016 22:01:52 +0000 (19:01 -0300)]
perf trace: Move msg_flags beautifier to tools/perf/trace/beauty/
To reduce the size of builtin-trace.c.
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-11zxg3qitk6bw2x30135k9z4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Wang Nan [Wed, 20 Apr 2016 18:59:54 +0000 (18:59 +0000)]
perf record: Generate tracking events for process forked by perf
With 'perf record --switch-output' without -a, record__synthesize() in
record__switch_output() won't generate tracking events because there's
no thread_map in evlist. Which causes newly created perf.data doesn't
contain map and comm information.
This patch creates a fake thread_map and directly call
perf_event__synthesize_thread_map() for those events.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
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/1461178794-40467-8-git-send-email-wangnan0@huawei.com
Signed-off-by: He Kuang <hekuang@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Wang Nan [Wed, 20 Apr 2016 18:59:52 +0000 (18:59 +0000)]
perf record: Disable buildid cache options by default in switch output mode
The cost of buildid cache processing is high: reading all events in
output perf.data, opening each elf file to read buildids then copying
them into ~/.debug directory. In switch output mode, these heavy works
block perf from receiving perf events for too long.
Enable no-buildid and no-buildid-cache by default if --switch-output is
provided. Still allow user use --no-no-buildid to explicitly enable
buildid in this case.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
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/1461178794-40467-6-git-send-email-wangnan0@huawei.com
Signed-off-by: He Kuang <hekuang@huawei.com>
[ Updated man page ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Wang Nan [Wed, 20 Apr 2016 18:59:51 +0000 (18:59 +0000)]
perf record: Force enable --timestamp-filename when --switch-output is provided
Without this patch, the last output doesn't have timestamp appended if
--timestamp-filename is not explicitly provided. For example:
# perf record -a --switch-output &
[1] 11224
# kill -s SIGUSR2 11224
[ perf record: dump data: Woken up 1 times ]
# [ perf record: Dump perf.data.
2015122622372823 ]
# fg
perf record -a --switch-output
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.027 MB perf.data (540 samples) ]
# ls -l
total 836
-rw------- 1 root root 33256 Dec 26 22:37 perf.data <---- *Odd*
-rw------- 1 root root 817156 Dec 26 22:37 perf.data.
2015122622372823
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
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/1461178794-40467-5-git-send-email-wangnan0@huawei.com
Signed-off-by: He Kuang <hekuang@huawei.com>
[ Updated man page, that also got an entry for --timestamp-filename ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Wang Nan [Wed, 20 Apr 2016 18:59:50 +0000 (18:59 +0000)]
perf record: Split output into multiple files via '--switch-output'
Allow 'perf record' to split its output into multiple files.
For example:
# ~/perf record -a --timestamp-filename --switch-output &
[1] 10763
# kill -s SIGUSR2 10763
[ perf record: dump data: Woken up 1 times ]
# [ perf record: Dump perf.data.
2015122622314468 ]
# kill -s SIGUSR2 10763
[ perf record: dump data: Woken up 1 times ]
# [ perf record: Dump perf.data.
2015122622314762 ]
# kill -s SIGUSR2 10763
[ perf record: dump data: Woken up 1 times ]
#[ perf record: Dump perf.data.
2015122622315171 ]
# fg
perf record -a --timestamp-filename --switch-output
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Dump perf.data.
2015122622315513 ]
[ perf record: Captured and wrote 0.014 MB perf.data.<timestamp> (296 samples) ]
# ls -l
total 920
-rw------- 1 root root 797692 Dec 26 22:31 perf.data.
2015122622314468
-rw------- 1 root root 59960 Dec 26 22:31 perf.data.
2015122622314762
-rw------- 1 root root 59912 Dec 26 22:31 perf.data.
2015122622315171
-rw------- 1 root root 19220 Dec 26 22:31 perf.data.
2015122622315513
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
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/1461178794-40467-4-git-send-email-wangnan0@huawei.com
Signed-off-by: He Kuang <hekuang@huawei.com>
[ Added man page entry, used the re-synthesize patch in this series as a fixup ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Wang Nan [Wed, 20 Apr 2016 18:59:49 +0000 (18:59 +0000)]
perf tools: Derive trigger class from auxtrace_snapshot
auxtrace_snapshot_state matches the trigger model. Use trigger to
implement it. auxtrace_snapshot_state and auxtrace_snapshot_err are
absorbed.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@redhat.com>
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/1461178794-40467-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Wang Nan [Wed, 20 Apr 2016 18:59:48 +0000 (18:59 +0000)]
perf tools: Introduce trigger class
Use 'trigger' to model operations which need to be executed when an
event (a signal, for example) is observed.
States and transits:
OFF--(on)--> READY --(hit)--> HIT
^ |
| (ready)
| |
\_____________/
is_hit and is_ready are two key functions to query the state of a
trigger. is_hit means the event already happen; is_ready means the
trigger is waiting for the event.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@redhat.com>
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/1461178794-40467-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Masami Hiramatsu [Wed, 27 Apr 2016 18:37:14 +0000 (03:37 +0900)]
perf probe: Use strbuf for making strings
Replace many fixed-length char array with strbuf to stringify
perf_probe_event and probe_trace_event etc.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20160427183713.23446.97377.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Wed, 27 Apr 2016 20:56:53 +0000 (17:56 -0300)]
perf evsel: Remove two extraneous ending newlines in open_strerror()
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>
Arnaldo Carvalho de Melo [Wed, 27 Apr 2016 20:51:45 +0000 (17:51 -0300)]
perf evsel: Handle ENOMEM for perf_event_max_stack + PERF_SAMPLE_CALLCHAIN
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>
Florian Fainelli [Mon, 25 Apr 2016 02:34:54 +0000 (19:34 -0700)]
bpf tools: Fix syscall argument
Coverity flagged this under CID
1354884 as a sizeof mismatch, it turns
out that the argument "attr" passed to syscall should have been a
pointer to attr in the first place.
Reported-by: coverity (CID 1354884)
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Wang Nan <wangnan0@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Fixes:
8f9e05fb298f ("perf tools: Fix PowerPC native building")
Link: http://lkml.kernel.org/r/1461551694-5512-3-git-send-email-f.fainelli@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Florian Fainelli [Mon, 25 Apr 2016 02:34:53 +0000 (19:34 -0700)]
bpf tools: Remove expression with no effect
Assigning "attr" to "attr" does not have any effect, but was caught by
Coverity, so let's remove this.
Reported-by: coverity (CID 1354720)
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Fixes:
1b76c13e4b36 ("bpf tools: Introduce 'bpf' library and add bpf feature check")
Link: http://lkml.kernel.org/r/1461551694-5512-2-git-send-email-f.fainelli@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Srinivas Pandruvada [Sun, 17 Apr 2016 22:03:01 +0000 (15:03 -0700)]
powercap, perf/x86/intel/rapl: Add PSys support
Skylake processor supports a new set of RAPL registers for controlling
entire SoC instead of just CPU package. This is useful for thermal
and power control when source of power/thermal is not just CPU/GPU.
This change adds a new platform domain (AKA PSys) to the current
power capping Intel RAPL driver.
PSys also supports PL1 (long term) and PL2 (short term) control like
package domain. This also follows same MSRs for energy and time
units as package domain.
Unlike package domain, PSys support requires more than just processor
level implementation. The other parts in the system need additional
implementation, which OEMs needs to support. So not all Skylake
systems will support PSys.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
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: bp@alien8.de
Cc: hpa@zytor.com
Cc: jacob.jun.pan@linux.intel.com
Cc: rjw@rjwysocki.net
Link: http://lkml.kernel.org/r/1460930581-29748-3-git-send-email-srinivas.pandruvada@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ingo Molnar [Thu, 28 Apr 2016 08:35:17 +0000 (10:35 +0200)]
Merge branch 'perf/urgent' into perf/core, to resolve conflict
Conflicts:
arch/x86/events/intel/pt.c
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Kan Liang [Thu, 21 Apr 2016 09:30:10 +0000 (02:30 -0700)]
perf/x86/intel: Fix incorrect lbr_sel_mask value
This patch fixes a bug which was introduced by:
b16a5b52eb90 ("perf/x86: Add option to disable reading branch flags/cycles")
In this patch, lbr_sel_mask is used to mask the lbr_select. But LBR_SEL_MASK
doesn't include the bit for LBR_CALL_STACK. So LBR call stack will never be
set in lbr_select.
This patch corrects the LBR_SEL_MASK by including all valid bits in
LBR_SELECT. Also, the LBR_CALL_STACK bit is different as other bit in
LBR_SELECT. It does not operate in suppress mode, so it needs to be
specially handled in intel_pmu_setup_hw_lbr_filter.
Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
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>
Link: http://lkml.kernel.org/r/1461231010-4399-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Alexander Shishkin [Tue, 29 Mar 2016 14:43:10 +0000 (17:43 +0300)]
perf/x86/intel/pt: Don't die on VMXON
Some versions of Intel PT do not support tracing across VMXON, more
specifically, VMXON will clear TraceEn control bit and any attempt to
set it before VMXOFF will throw a #GP, which in the current state of
things will crash the kernel. Namely:
$ perf record -e intel_pt// kvm -nographic
on such a machine will kill it.
To avoid this, notify the intel_pt driver before VMXON and after
VMXOFF so that it knows when not to enable itself.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
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: hpa@zytor.com
Link: http://lkml.kernel.org/r/87oa9dwrfk.fsf@ashishki-desk.ger.corp.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Tue, 26 Apr 2016 09:36:53 +0000 (11:36 +0200)]
perf/core: Fix perf_event_open() vs. execve() race
Jann reported that the ptrace_may_access() check in
find_lively_task_by_vpid() is racy against exec().
Specifically:
perf_event_open() execve()
ptrace_may_access()
commit_creds()
... if (get_dumpable() != SUID_DUMP_USER)
perf_event_exit_task();
perf_install_in_context()
would result in installing a counter across the creds boundary.
Fix this by wrapping lots of perf_event_open() in cred_guard_mutex.
This should be fine as perf_event_exit_task() is already called with
cred_guard_mutex held, so all perf locks already nest inside it.
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
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>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Adam Borowski [Wed, 27 Apr 2016 09:35:31 +0000 (11:35 +0200)]
perf/x86/amd: Set the size of event map array to PERF_COUNT_HW_MAX
The entry for PERF_COUNT_HW_REF_CPU_CYCLES is not used on AMD, but is
referenced by filter_events() which expects undefined events to have a
value of 0.
Found via KASAN:
UBSAN: Undefined behaviour in arch/x86/events/amd/core.c:132:30
index 9 is out of range for type 'u64 [9]'
UBSAN: Undefined behaviour in arch/x86/events/amd/core.c:132:9
load of address
ffffffff81c021c8 with insufficient space for an object of type 'const u64'
Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
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>
Link: http://lkml.kernel.org/r/1461749731-30979-1-git-send-email-kilobyte@angband.pl
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ingo Molnar [Wed, 27 Apr 2016 15:02:24 +0000 (17:02 +0200)]
Merge tag 'perf-core-for-mingo-
20160427' of git://git./linux/kernel/git/acme/linux into perf/core
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
User visible changes:
- perf trace --pf maj/min/all works with --call-graph: (Arnaldo Carvalho de Melo)
Tracing write syscalls and major page faults with callchains while starting
firefox, limiting the stack to 5 frames:
# perf trace -e write --pf maj --max-stack 5 firefox
589.549 ( 0.014 ms): firefox/15377 write(fd: 4, buf: 0x7fff80acc898, count: 151) = 151
[0xfaed] (/usr/lib64/libpthread-2.22.so)
fire_glxtest_process+0x5c (/usr/lib64/firefox/libxul.so)
InstallGdkErrorHandler+0x41 (/usr/lib64/firefox/libxul.so)
XREMain::XRE_mainInit+0x12c (/usr/lib64/firefox/libxul.so)
XREMain::XRE_main+0x1e4 (/usr/lib64/firefox/libxul.so)
760.704 ( 0.000 ms): firefox/15332 majfault [gtk_tree_view_accessible_get_type+0x0] => /usr/lib64/libgtk-3.so.0.1800.9@0xa0850 (x.)
gtk_tree_view_accessible_get_type+0x0 (/usr/lib64/libgtk-3.so.0.1800.9)
gtk_tree_view_class_intern_init+0x1a54 (/usr/lib64/libgtk-3.so.0.1800.9)
g_type_class_ref+0x6dd (/usr/lib64/libgobject-2.0.so.0.4600.2)
[0x115378] (/usr/lib64/libgnutls.so.30.6.3)
This automagically selects "--call-graph dwarf", use "--call-graph fp" on systems
where -fno-omit-frame-pointer was used to built the components of interest, to
incur in less overhead, or tune "--call-graph dwarf" appropriately, see 'perf record --help'.
- Allow /proc/sys/kernel/perf_event_max_stack, that defaults to the old hard coded value
of PERF_MAX_STACK_DEPTH (127), useful for huge callstacks for things like Groovy, Ruby, etc,
and also to reduce overhead by limiting it to a smaller value, upcoming work will allow
this to be done per-event (Arnaldo Carvalho de Melo)
- Make 'perf trace --min-stack' be honoured by --pf and --event (Arnaldo Carvalho de Melo)
- Make 'perf evlist -v' decode perf_event_attr->branch_sample_type (Arnaldo Carvalho de Melo)
# perf record --call lbr usleep 1
# perf evlist -v
cycles:ppp: ... sample_type: IP|TID|TIME|CALLCHAIN|PERIOD|BRANCH_STACK, ...
branch_sample_type: USER|CALL_STACK|NO_FLAGS|NO_CYCLES
#
- Clear dummy entry accumulated period, fixing such 'perf top/report' output
as: (Kan Liang)
4769.98% 0.01% 0.00% 0.01% tchain_edit [kernel] [k] update_fast_timekeeper
- System calls with pid_t arguments gets them augmented with the COMM event
more thoroughly:
# trace -e perf_event_open perf stat -e cycles -p 15608
6.876 ( 0.014 ms): perf_event_open(attr_uptr: 0x2ae20d8, pid: 15608 (hexchat), cpu: -1, group_fd: -1, flags: FD_CLOEXEC) = 3
6.882 ( 0.005 ms): perf_event_open(attr_uptr: 0x2ae20d8, pid: 15639 (gmain), cpu: -1, group_fd: -1, flags: FD_CLOEXEC) = 4
6.889 ( 0.005 ms): perf_event_open(attr_uptr: 0x2ae20d8, pid: 15640 (gdbus), cpu: -1, group_fd: -1, flags: FD_CLOEXEC) = 5
^^^^^^^^^^^^^^^^^^
^C
- Fix offline module name mismatch issue in 'perf probe' (Ravi Bangoria)
- Fix module probe issue if no dwarf support in (Ravi Bangoria)
Assorted fixes:
- Fix off-by-one in write_buildid() (Andrey Ryabinin)
- Fix segfault when printing callchains in 'perf script' (Chris Phlipot)
- Replace assignment with comparison on assert check in 'perf test' entry (Colin Ian King)
- Fix off-by-one comparison in intel-pt code (Colin Ian King)
- Close target file on error path in 'perf probe' (Masami Hiramatsu)
- Set default kprobe group name if not given in 'perf probe' (Masami Hiramatsu)
- Avoid partial perf_event_header reads (Wang Nan)
Infrastructure changes:
- Update x86's syscall_64.tbl copy, adding preadv2 & pwritev2 (Arnaldo Carvalho de Melo)
- Make the x86 clean quiet wrt syscall table removal (Jiri Olsa)
Cleanups:
- Simplify wrapper for LOCK_PI in 'perf bench futex' (Davidlohr Bueso)
- Remove duplicate const qualifier (Eric Engestrom)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Arnaldo Carvalho de Melo [Wed, 27 Apr 2016 13:16:24 +0000 (10:16 -0300)]
perf tools: Set the maximum allowed stack from /proc/sys/kernel/perf_event_max_stack
There is an upper limit to what tooling considers a valid callchain,
and it was tied to the hardcoded value in the kernel,
PERF_MAX_STACK_DEPTH (127), now that this can be tuned via a sysctl,
make it read it and use that as the upper limit, falling back to
PERF_MAX_STACK_DEPTH for kernels where this sysctl isn't present.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: David Ahern <dsahern@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-yjqsd30nnkogvj5oyx9ghir9@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Thu, 21 Apr 2016 15:28:50 +0000 (12:28 -0300)]
perf core: Allow setting up max frame stack depth via sysctl
The default remains 127, which is good for most cases, and not even hit
most of the time, but then for some cases, as reported by Brendan, 1024+
deep frames are appearing on the radar for things like groovy, ruby.
And in some workloads putting a _lower_ cap on this may make sense. One
that is per event still needs to be put in place tho.
The new file is:
# cat /proc/sys/kernel/perf_event_max_stack
127
Chaging it:
# echo 256 > /proc/sys/kernel/perf_event_max_stack
# cat /proc/sys/kernel/perf_event_max_stack
256
But as soon as there is some event using callchains we get:
# echo 512 > /proc/sys/kernel/perf_event_max_stack
-bash: echo: write error: Device or resource busy
#
Because we only allocate the callchain percpu data structures when there
is a user, which allows for changing the max easily, its just a matter
of having no callchain users at that point.
Reported-and-Tested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.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: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/20160426002928.GB16708@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Tue, 26 Apr 2016 16:27:23 +0000 (13:27 -0300)]
perf bench: Remove one more die() call
Propagate the error instead.
Cc: David Ahern <dsahern@gmail.com>
Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
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-z6erjg35d1gekevwujoa0223@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Tue, 26 Apr 2016 15:58:45 +0000 (12:58 -0300)]
perf tools: Update x86's syscall_64.tbl, adding preadv2 & pwritev2
Introduced in commit
4babf2c5efb7 ("x86: wire up preadv2 and pwritev2").
This will make 'perf trace' aware of them.
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-vojoylgce2cetsy36446s5ny@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Ravi Bangoria [Tue, 26 Apr 2016 14:25:40 +0000 (19:55 +0530)]
perf probe: Fix module probe issue if no dwarf support
Perf is not able to register probe in kernel module when dwarf supprt
is not there(and so it goes for symtab). Perf passes full path of
module where only module name is required which is causing the problem.
This patch fixes this issue.
Before applying patch:
$ dpkg -s libdw-dev
dpkg-query: package 'libdw-dev' is not installed and no information is...
$ sudo ./perf probe -m /linux/samples/kprobes/kprobe_example.ko kprobe_init
Added new event:
probe:kprobe_init (on kprobe_init in /linux/samples/kprobes/kprobe_example.ko)
You can now use it in all perf tools, such as:
perf record -e probe:kprobe_init -aR sleep 1
$ sudo cat /sys/kernel/debug/tracing/kprobe_events
p:probe/kprobe_init /linux/samples/kprobes/kprobe_example.ko:kprobe_init
$ sudo ./perf record -a -e probe:kprobe_init
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.105 MB perf.data ]
$ sudo ./perf script # No output here
After applying patch:
$ sudo ./perf probe -m /linux/samples/kprobes/kprobe_example.ko kprobe_init
Added new event:
probe:kprobe_init (on kprobe_init in kprobe_example)
You can now use it in all perf tools, such as:
perf record -e probe:kprobe_init -aR sleep 1
$ sudo cat /sys/kernel/debug/tracing/kprobe_events
p:probe/kprobe_init kprobe_example:kprobe_init
$ sudo ./perf record -a -e probe:kprobe_init
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.105 MB perf.data (2 samples) ]
$ sudo ./perf script
insmod 13990 [002] 5961.216833: probe:kprobe_init: ...
insmod 13995 [002] 5962.889384: probe:kprobe_init: ...
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1461680741-12517-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Ravi Bangoria [Tue, 26 Apr 2016 14:25:41 +0000 (19:55 +0530)]
perf probe: Fix offline module name missmatch issue
Perf can add a probe on kernel module which has not been loaded yet.
The current implementation finds the module name from path. But if the
filename is different from the actual module name then perf fails to
register a probe while loading module because of mismatch in the names.
For example, samples/kobject/kobject-example.ko is loaded as
kobject_example.
Before applying patch:
$ sudo ./perf probe -m /linux/samples/kobject/kobject-example.ko foo_show
Added new event:
probe:foo_show (on foo_show in kobject-example)
You can now use it in all perf tools, such as:
perf record -e probe:foo_show -aR sleep 1
$ cat /sys/kernel/debug/tracing/kprobe_events
p:probe/foo_show kobject-example:foo_show
$ insmod kobject-example.ko
$ lsmod
Module Size Used by
kobject_example 16384 0
Generate read to /sys/kernel/kobject_example/foo while recording data
with below command
$ sudo ./perf record -e probe:foo_show -a
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.093 MB perf.data ]
$./perf report --stdio -F overhead,comm,dso,sym
Error:
The perf.data.old file has no samples!
After applying patch:
$ sudo ./perf probe -m /linux/samples/kobject/kobject-example.ko foo_show
Added new event:
probe:foo_show (on foo_show in kobject_example)
You can now use it in all perf tools, such as:
perf record -e probe:foo_show -aR sleep 1
$ sudo cat /sys/kernel/debug/tracing/kprobe_events
p:probe/foo_show kobject_example:foo_show
$ insmod kobject-example.ko
$ lsmod
Module Size Used by
kobject_example 16384 0
Generate read to /sys/kernel/kobject_example/foo while recording data
with below command
$ sudo ./perf record -e probe:foo_show -a
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.097 MB perf.data (8 samples) ]
$ sudo ./perf report --stdio -F overhead,comm,dso,sym
...
# Samples: 8 of event 'probe:foo_show'
# Event count (approx.): 8
#
# Overhead Command Shared Object Symbol
# ........ ....... ................. ............
#
100.00% cat [kobject_example] [k] foo_show
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1461680741-12517-2-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Tue, 26 Apr 2016 15:33:46 +0000 (12:33 -0300)]
perf trace: Read thread's COMM from /proc when not set
We get notifications for threads that gets created while we're tracing,
but for preexisting threads we may end not having synthesized them, like
when tracing a 'perf trace' session that will use '--pid' to trace some
other thread.
And besides we should probably stop synthesizing those records and
instead read thread information in a lazy way, i.e. just when we need,
like done in this patch:
Now the 'pid_t' argument in 'perf_event_open' gets translated to a COMM:
# perf trace -e perf_event_open perf stat -e cycles -p 31601
0.027 ( 0.027 ms): perf/23393 perf_event_open(attr_uptr: 0x2fdd0d8, pid: 31601 (abrt-dump-journ), cpu: -1, group_fd: -1, flags: FD_CLOEXEC)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
= 3
^C
And in other syscalls containing pid_t without thread->comm_set at the
time of the formatting.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
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-ioeps6dlwst17d6oozc9shtk@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Tue, 26 Apr 2016 15:32:50 +0000 (12:32 -0300)]
perf thread: Introduce method to set comm from /proc/pid/self
Will be used for lazy comm loading in 'perf trace'.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
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-7ogbkuoka1y2qsmcckqxvl5m@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Tue, 26 Apr 2016 15:31:16 +0000 (12:31 -0300)]
tools lib api fs: Add helper to read string from procfs file
To read things like /proc/self/comm.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
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-ztpkbmseidt0hq2psr46o0h9@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Tue, 26 Apr 2016 14:40:17 +0000 (11:40 -0300)]
perf trace: Do not beautify the 'pid' parameter as a simple integer
Leave it alone so that it ends up assigned to SCA_PID via its type,
'pid_t', that will look up the pid on the machine thread rb_tree and
possibly find its COMM.
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-r7dujgmhtxxfajuunpt1bkuo@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Tue, 26 Apr 2016 14:03:03 +0000 (11:03 -0300)]
perf trace: Move perf_flags beautifier to tools/perf/trace/beauty/
To reduce the size of builtin-trace.c.
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-8r3gmymyn3r0ynt4yuzspp9g@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Masami Hiramatsu [Tue, 26 Apr 2016 09:04:13 +0000 (18:04 +0900)]
perf probe: Set default kprobe group name if it is not given
Set kprobe group name as "probe" if it is not given.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20160426090413.11891.95640.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Masami Hiramatsu [Tue, 26 Apr 2016 09:03:04 +0000 (18:03 +0900)]
perf probe: Let probe_file__add_event return 0 if succeeded
Since other methods return 0 if succeeded (or filedesc), let
probe_file__add_event() return 0 instead of the length of written bytes.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20160426090303.11891.18232.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Masami Hiramatsu [Tue, 26 Apr 2016 09:02:42 +0000 (18:02 +0900)]
perf tools: Add lsdir() helper to read a directory
As a utility function, add lsdir() which reads given directory and store
entry name into a strlist. lsdir accepts a filter function so that user
can filter out unneeded entries.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20160426090242.11891.79014.stgit@devbox
[ Do not use the 'dirname' it is used in some distros ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Masami Hiramatsu [Tue, 26 Apr 2016 06:47:37 +0000 (15:47 +0900)]
perf probe: Close target file on error path
Fix a bug to close target elf file in get_text_start_address().
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20160426064737.1443.44093.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Wang Nan [Tue, 26 Apr 2016 02:28:54 +0000 (02:28 +0000)]
perf evlist: Enforce ring buffer reading
Don't read broken data after 'head' pointer.
Following commits will feed perf_evlist__mmap_read() with some 'head'
pointers not maintained by kernel. If 'head' pointer breaks an event, we
should avoid reading from the broken event. This can happen in backward
ring buffer.
For example:
old head
| |
V V
+---+------+----------+----+-----+--+
|..E|D....D|C........C|B..B|A....|E.|
+---+------+----------+----+-----+--+
'old' pointer points to the beginning of 'A' and trying read from it,
but 'A' has been overwritten. In this case, don't try to read from 'A',
simply return NULL.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1461637738-62722-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Kan Liang [Mon, 25 Apr 2016 06:28:09 +0000 (23:28 -0700)]
perf hists: Clear dummy entry accumulated period
The accumulated period for dummy entry should also be 0. Otherwise, the
total overhead could be overcounted.
$ perf record -e '{LLC-load-misses,cpu/instructions/}' --call-graph=lbr ./tchain
$ perf report --stdio
# To display the perf.data header info, please use --header/--header-only options.
#
# Total Lost Samples: 0
#
# Samples: 21K of event 'anon group { LLC-load-misses, cpu/instructions/ }'
# Event count (approx.):
16313667937
#
# Children Self Command Shared Object Symbol
# ................ ................ ........... ................ ............................
#
4769.98% 0.01% 0.00% 0.01% tchain_edit [kernel.vmlinux] [k] update_fast_timekeeper
4356.18% 0.01% 0.00% 0.01% tchain_edit [kernel.vmlinux] [k] trigger_load_balance
3181.12% 0.01% 0.00% 0.01% tchain_edit [kernel.vmlinux] [k] irq_work_tick
1592.37% 0.00% 0.00% 0.00% tchain_edit [kernel.vmlinux] [k] cpu_needs_another_gp
Signed-off-by: Kan Liang <kan.liang@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1461565689-5862-1-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Colin Ian King [Sun, 24 Apr 2016 18:56:43 +0000 (19:56 +0100)]
perf intel-pt: Fix off-by-one comparison on maximum code
The check for the maximum code is off-by-one; the current comparison of
a code that is INTEL_PT_ERR_MAX will cause the strlcpy to perform an out
of bounds array access on the intel_pt_err_msgs array.
Fix this with a >= comparison.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1461524203-10224-1-git-send-email-colin.king@canonical.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Davidlohr Bueso [Thu, 21 Apr 2016 03:14:07 +0000 (20:14 -0700)]
perf bench futex: Simplify wrapper for LOCK_PI
Given that the 'val' parameter is ignored for FUTEX_LOCK_PI, get rid of
the bogus deadlock detection flag in the wrapper code and avoid the
extra argument, making it resemble its unlock counterpart. And if
nothing else, we already only pass 0 anyway.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Davidlohr Bueso <dbueso@suse.de>
Link: http://lkml.kernel.org/r/1461208447-29328-1-git-send-email-dave@stgolabs.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Colin Ian King [Sat, 23 Apr 2016 13:45:54 +0000 (14:45 +0100)]
perf tests: Replace assignment with comparison on assert check
The current assert check is checking an assignment, which will always be
true. Instead, the assert should be checking if scale is equal to 0.122
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1461419154-16918-1-git-send-email-colin.king@canonical.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Eric Engestrom [Mon, 25 Apr 2016 09:47:54 +0000 (10:47 +0100)]
perf tools: Remove duplicate const qualifier
Signed-off-by: Eric Engestrom <eric.engestrom@imgtec.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1461577678-29517-1-git-send-email-eric.engestrom@imgtec.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Jiri Olsa [Mon, 25 Apr 2016 20:17:18 +0000 (22:17 +0200)]
tools build: Fix perf_clean target
Fix perf_clean target to follow the same logic as perf target.
Fixes the following make invokation:
$ cd <kernelsrc> && make tools/perf_clean
Reported-by: TJ <linux@iam.tj>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=116411
Link: http://lkml.kernel.org/r/1461615438-27894-2-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Jiri Olsa [Mon, 25 Apr 2016 20:17:17 +0000 (22:17 +0200)]
perf tools: Make the x86 clean quiet
Turn current clean output:
$ make clean
rm -f arch/x86/include/generated/asm/syscalls_64.c
CLEAN libbpf
CLEAN libapi
into:
$ make clean
CLEAN x86
CLEAN libapi
CLEAN libbpf
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: TJ <linux@iam.tj>
Link: http://lkml.kernel.org/r/1461615438-27894-1-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Mon, 25 Apr 2016 19:45:29 +0000 (16:45 -0300)]
perf evlist: Decode perf_event_attr->branch_sample_type
While trying to use --call-graph lbr in 'perf trace', since we only are
interested in the callchain for userspace, up to the callchain, I found
that 'perf evlist' is not decoding the branch_sample_type field, fix it.
Before:
# perf record --call-graph lbr usleep 1
# perf evlist -v
cycles:ppp: size: 112, { sample_period, sample_freq }: 4000,
sample_type: IP|TID|TIME|CALLCHAIN|CPU|PERIOD|BRANCH_STACK,
disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, task: 1,
precise_ip: 3, sample_id_all: 1, exclude_guest: 1, mmap2: 1,
comm_exec: 1, branch_sample_type: 51201
^^^^^^^^^^^^^^^^^^^^^^^^^
After:
# perf evlist -v
cycles:ppp: size: 112, { sample_period, sample_freq }: 4000,
sample_type: IP|TID|TIME|CALLCHAIN|CPU|PERIOD|BRANCH_STACK,
disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, task: 1,
precise_ip: 3, sample_id_all: 1, exclude_guest: 1, mmap2: 1,
comm_exec: 1, branch_sample_type: USER|CALL_STACK|NO_FLAGS|NO_CYCLES
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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-hozai7974u0ulgx13k96fcaw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Wed, 20 Apr 2016 23:06:02 +0000 (20:06 -0300)]
perf trace: Make --pf honour --min-stack too
To check deeply nested page fault callchains.
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-wuji34xx003kr88nmqt6jkgf@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Wed, 20 Apr 2016 22:55:48 +0000 (19:55 -0300)]
perf trace: Make --event honour --min-stack too
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-shj0fazntmskhjild5i6x73l@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Chris Phlipot [Wed, 20 Apr 2016 02:32:11 +0000 (19:32 -0700)]
perf script: Fix segfault when printing callchains
This fixes a bug caused by an unitialized callchain cursor. The crash
frist appeared in:
6f736735e30f ("perf evsel: Require that callchains be resolved before
calling fprintf_{sym,callchain}")
The callchain cursor is a struct that contains pointers, that when
uninitialized will cause unpredictable behavior (usually a crash)
when trying to append to the callchain.
The existing implementation has the following issues:
1. The callchain cursor used is not initialized, resulting in
unpredictable behavior when used.
2. The cursor is declared on the stack. Even if it is properly initalized,
the implmentation will leak memory when the function returns,
since all the references to the callchain_nodes allocated by
callchain_cursor_append will be lost when the cursor goes out of
scope.
3. Storing the cursor on the stack is inefficient. Even if memory is
properly freed when it goes out of scope, a performance penalty
will be incurred due to reallocation of callchain nodes.
callchain_cursor_append is designed to avoid these reallocations
when an existing cursor is reused.
This patch fixes the crash by replacing cursor_callchain with a reference
to the global callchain_cursor which also resolves all 3 issues mentioned
above.
How to reproduce the crash:
$ perf record --call-graph=dwarf stress -t 1 -c 1
$ perf script > /dev/null
Segfault
Signed-off-by: Chris Phlipot <cphlipot0@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes:
6f736735e30f ("perf evsel: Require that callchains be resolved before calling fprintf_{sym,callchain}")
Link: http://lkml.kernel.org/r/1461119531-2529-1-git-send-email-cphlipot0@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Tue, 19 Apr 2016 19:31:12 +0000 (16:31 -0300)]
perf trace: Make --pf maj/min/all use callchains too
Forgot about page faults, a software event, when adding support for callchains,
fix it:
# trace --no-syscalls --pf maj --call dwarf
0.000 ( 0.000 ms): Xorg/2068 majfault [sfbSegment1+0x0] => /usr/lib64/xorg/modules/drivers/intel_drv.so@0x11b490 (x.)
sfbSegment1+0x0 (/usr/lib64/xorg/modules/drivers/intel_drv.so)
fbPolySegment32+0x361 (/usr/lib64/xorg/modules/drivers/intel_drv.so)
sna_poly_segment+0x743 (/usr/lib64/xorg/modules/drivers/intel_drv.so)
damagePolySegment+0x77 (/usr/libexec/Xorg)
ProcPolySegment+0xe7 (/usr/libexec/Xorg)
Dispatch+0x25f (/usr/libexec/Xorg)
dix_main+0x3c3 (/usr/libexec/Xorg)
__libc_start_main+0xf0 (/usr/lib64/libc-2.22.so)
_start+0x29 (/usr/libexec/Xorg)
0.257 ( 0.000 ms): Xorg/2068 majfault [miZeroClipLine+0x0] => /usr/libexec/Xorg@0x18e830 (x.)
miZeroClipLine+0x0 (/usr/libexec/Xorg)
_fbSegment+0x2c0 (/usr/lib64/xorg/modules/drivers/intel_drv.so)
sfbSegment1+0x67 (/usr/lib64/xorg/modules/drivers/intel_drv.so)
fbPolySegment32+0x361 (/usr/lib64/xorg/modules/drivers/intel_drv.so)
sna_poly_segment+0x743 (/usr/lib64/xorg/modules/drivers/intel_drv.so)
damagePolySegment+0x77 (/usr/libexec/Xorg)
ProcPolySegment+0xe7 (/usr/libexec/Xorg)
Dispatch+0x25f (/usr/libexec/Xorg)
dix_main+0x3c3 (/usr/libexec/Xorg)
__libc_start_main+0xf0 (/usr/lib64/libc-2.22.so)
_start+0x29 (/usr/libexec/Xorg)
^C#
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-8h6ssirw5z15qyhy2lwd6f89@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Tue, 19 Apr 2016 19:00:01 +0000 (16:00 -0300)]
perf trace: Extract evsel contructor from perf_evlist__add_pgfault
Prep work for next patches, where we'll need access to the created
evsels, to possibly configure callchains.
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-2pcgsgnkgellhlcao4aub8tu@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Andrey Ryabinin [Tue, 19 Apr 2016 08:17:27 +0000 (11:17 +0300)]
perf buildid: Fix off-by-one in write_buildid()
write_buildid() increments 'name_len' with intention to take into
account trailing zero byte. However, 'name_len' was already incremented
in machine__write_buildid_table() before. So this leads to
out-of-bounds read in do_write():
$ ./perf record sleep 0
[ perf record: Woken up 1 times to write data ]
=================================================================
==15899==ERROR: AddressSanitizer: global-buffer-overflow on address 0x00000099fc92 at pc 0x7f1aa9c7eab5 bp 0x7fff940f84d0 sp 0x7fff940f7c78
READ of size 19 at 0x00000099fc92 thread T0
#0 0x7f1aa9c7eab4 (/usr/lib/gcc/x86_64-pc-linux-gnu/5.3.0/libasan.so.2+0x44ab4)
#1 0x649c5b in do_write util/header.c:67
#2 0x649c5b in write_padded util/header.c:82
#3 0x57e8bc in write_buildid util/build-id.c:239
#4 0x57e8bc in machine__write_buildid_table util/build-id.c:278
...
0x00000099fc92 is located 0 bytes to the right of global variable '*.LC99' defined in 'util/symbol.c' (0x99fc80) of size 18
'*.LC99' is ascii string '[kernel.kallsyms]'
...
Shadow bytes around the buggy address:
0x00008012bf80: f9 f9 f9 f9 00 00 00 00 00 00 03 f9 f9 f9 f9 f9
=>0x00008012bf90: 00 00[02]f9 f9 f9 f9 f9 00 00 00 00 00 05 f9 f9
0x00008012bfa0: f9 f9 f9 f9 00 03 f9 f9 f9 f9 f9 f9 00 00 00 00
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1461053847-5633-1-git-send-email-aryabinin@virtuozzo.com
[ Remove the off-by one at the origin, to keep len(s) == strlen(s) assumption ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Ingo Molnar [Tue, 19 Apr 2016 18:58:22 +0000 (20:58 +0200)]
Merge tag 'perf-core-for-mingo-
20160419' of git://git./linux/kernel/git/acme/linux
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
Build fixes:
- Fix 'perf trace' build when DWARF unwind isn't available (Arnaldo Carvalho de Melo)
- Remove x86 references from arch-neutral Build, fixing it in !x86 arches,
reported as breaking the build for powerpc64le in linux-next (Arnaldo Carvalho de Melo)
Infrastructure changes:
- Do memset() variable 'st' using the correct size in the jit code (Colin Ian King)
- Fix postgresql ubuntu 'perf script' install instructions (Chris Phlipot)
- Use callchain_param more thoroughly when checking how callchains were
configured, eventually will be the only way to look for callchain parameters
(Arnaldo Carvalho de Melo)
- Fix some issues in the 'perf test kallsyms' entry (Arnaldo Carvalho de Melo)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Thu, 21 Apr 2016 13:15:47 +0000 (15:15 +0200)]
x86/perf/rapl: Add missing Broadwell model
With the array aligned as per events/intel/core.c it was fairly
obvious we missed one, add it in.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Thu, 21 Apr 2016 13:14:17 +0000 (15:14 +0200)]
x86/perf/rapl: Reorder model numbers
Re-order the model array to match the order in events/intel/core.c,
to easier spot gaps and such.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Srinivas Pandruvada [Sun, 17 Apr 2016 22:03:00 +0000 (15:03 -0700)]
perf/x86/intel/rapl: Support Skylake RAPL domains
Add Skylake client support for RAPL domains. In addition to RAPL domains
in Broadwell clients, it has support for platform domain (aka PSys). The
PSys domain controls the entire SoC instead of just a CPU package. Unlike
package domain, PSys support requires more than just processor level
implementation. The other parts in the system need additional HW level
signaling, which OEMs need to support. When not supported, the energy
counter register in PSys domain returns 0.
Also corrected error in comment for GPU counter, which previously was
DRAM counter.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com
[ Cnverted to model_match stuff. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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: bp@alien8.de
Cc: hpa@zytor.com
Cc: jacob.jun.pan@linux.intel.com
Cc: rjw@rjwysocki.net
Link: http://lkml.kernel.org/r/1460930581-29748-2-git-send-email-srinivas.pandruvada@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Wang Nan [Tue, 5 Apr 2016 14:11:18 +0000 (14:11 +0000)]
perf/core: Add ::write_backward attribute to perf event
This patch introduces 'write_backward' bit to perf_event_attr, which
controls the direction of a ring buffer. After set, the corresponding
ring buffer is written from end to beginning. This feature is design to
support reading from overwritable ring buffer.
Ring buffer can be created by mapping a perf event fd. Kernel puts event
records into ring buffer, user tooling like perf fetch them from
address returned by mmap(). To prevent racing between kernel and tooling,
they communicate to each other through 'head' and 'tail' pointers.
Kernel maintains 'head' pointer, points it to the next free area (tail
of the last record). Tooling maintains 'tail' pointer, points it to the
tail of last consumed record (record has already been fetched). Kernel
determines the available space in a ring buffer using these two
pointers to avoid overwrite unfetched records.
By mapping without 'PROT_WRITE', an overwritable ring buffer is created.
Different from normal ring buffer, tooling is unable to maintain 'tail'
pointer because writing is forbidden. Therefore, for this type of ring
buffers, kernel overwrite old records unconditionally, works like flight
recorder. This feature would be useful if reading from overwritable ring
buffer were as easy as reading from normal ring buffer. However,
there's an obscure problem.
The following figure demonstrates a full overwritable ring buffer. In
this figure, the 'head' pointer points to the end of last record, and a
long record 'E' is pending. For a normal ring buffer, a 'tail' pointer
would have pointed to position (X), so kernel knows there's no more
space in the ring buffer. However, for an overwritable ring buffer,
kernel ignore the 'tail' pointer.
(X) head
. |
. V
+------+-------+----------+------+---+
|A....A|B.....B|C........C|D....D| |
+------+-------+----------+------+---+
Record 'A' is overwritten by event 'E':
head
|
V
+--+---+-------+----------+------+---+
|.E|..A|B.....B|C........C|D....D|E..|
+--+---+-------+----------+------+---+
Now tooling decides to read from this ring buffer. However, none of these
two natural positions, 'head' and the start of this ring buffer, are
pointing to the head of a record. Even the full ring buffer can be
accessed by tooling, it is unable to find a position to start decoding.
The first attempt tries to solve this problem AFAIK can be found from
[1]. It makes kernel to maintain 'tail' pointer: updates it when ring
buffer is half full. However, this approach introduces overhead to
fast path. Test result shows a 1% overhead [2]. In addition, this method
utilizes no more tham 50% records.
Another attempt can be found from [3], which allows putting the size of
an event at the end of each record. This approach allows tooling to find
records in a backward manner from 'head' pointer by reading size of a
record from its tail. However, because of alignment requirement, it
needs 8 bytes to record the size of a record, which is a huge waste. Its
performance is also not good, because more data need to be written.
This approach also introduces some extra branch instructions to fast
path.
'write_backward' is a better solution to this problem.
Following figure demonstrates the state of the overwritable ring buffer
when 'write_backward' is set before overwriting:
head
|
V
+---+------+----------+-------+------+
| |D....D|C........C|B.....B|A....A|
+---+------+----------+-------+------+
and after overwriting:
head
|
V
+---+------+----------+-------+---+--+
|..E|D....D|C........C|B.....B|A..|E.|
+---+------+----------+-------+---+--+
In each situation, 'head' points to the beginning of the newest record.
From this record, tooling can iterate over the full ring buffer and fetch
records one by one.
The only limitation that needs to be considered is back-to-back reading.
Due to the non-deterministic of user programs, it is impossible to ensure
the ring buffer keeps stable during reading. Consider an extreme situation:
tooling is scheduled out after reading record 'D', then a burst of events
come, eat up the whole ring buffer (one or multiple rounds). When the
tooling process comes back, reading after 'D' is incorrect now.
To prevent this problem, we need to find a way to ensure the ring buffer
is stable during reading. ioctl(PERF_EVENT_IOC_PAUSE_OUTPUT) is
suggested because its overhead is lower than
ioctl(PERF_EVENT_IOC_ENABLE).
By carefully verifying 'header' pointer, reader can avoid pausing the
ring-buffer. For example:
/* A union of all possible events */
union perf_event event;
p = head = perf_mmap__read_head();
while (true) {
/* copy header of next event */
fetch(&event.header, p, sizeof(event.header));
/* read 'head' pointer */
head = perf_mmap__read_head();
/* check overwritten: is the header good? */
if (!verify(sizeof(event.header), p, head))
break;
/* copy the whole event */
fetch(&event, p, event.header.size);
/* read 'head' pointer again */
head = perf_mmap__read_head();
/* is the whole event good? */
if (!verify(event.header.size, p, head))
break;
p += event.header.size;
}
However, the overhead is high because:
a) In-place decoding is not safe.
Copying-verifying-decoding is required.
b) Fetching 'head' pointer requires additional synchronization.
(From Alexei Starovoitov:
Even when this trick works, pause is needed for more than stability of
reading. When we collect the events into overwrite buffer we're waiting
for some other trigger (like all cpu utilization spike or just one cpu
running and all others are idle) and when it happens the buffer has
valuable info from the past. At this point new events are no longer
interesting and buffer should be paused, events read and unpaused until
next trigger comes.)
This patch utilizes event's default overflow_handler introduced
previously. perf_event_output_backward() is created as the default
overflow handler for backward ring buffers. To avoid extra overhead to
fast path, original perf_event_output() becomes __perf_event_output()
and marked '__always_inline'. In theory, there's no extra overhead
introduced to fast path.
Performance testing:
Calling
3000000 times of 'close(-1)', use gettimeofday() to check
duration. Use 'perf record -o /dev/null -e raw_syscalls:*' to capture
system calls. In ns.
Testing environment:
CPU : Intel(R) Core(TM) i7-4790 CPU @ 3.60GHz
Kernel : v4.5.0
MEAN STDVAR
BASE 800214.950 2853.083
PRE1
2253846.700 9997.014
PRE2
2257495.540 8516.293
POST
2250896.100 8933.921
Where 'BASE' is pure performance without capturing. 'PRE1' is test
result of pure 'v4.5.0' kernel. 'PRE2' is test result before this
patch. 'POST' is test result after this patch. See [4] for the detailed
experimental setup.
Considering the stdvar, this patch doesn't introduce performance
overhead to the fast path.
[1] http://lkml.iu.edu/hypermail/linux/kernel/1304.1/04584.html
[2] http://lkml.iu.edu/hypermail/linux/kernel/1307.1/00535.html
[3] http://lkml.iu.edu/hypermail/linux/kernel/1512.0/01265.html
[4] http://lkml.kernel.org/g/
56F89DCD.
1040202@huawei.com
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: <acme@kernel.org>
Cc: <pi3orama@163.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.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: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1459865478-53413-1-git-send-email-wangnan0@huawei.com
[ Fixed the changelog some more. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Kan Liang [Fri, 15 Apr 2016 07:53:45 +0000 (00:53 -0700)]
perf/x86/intel: Add LBR filter support for Silvermont and Airmont CPUs
LBR filtering is also supported on the Silvermont and Airmont
microarchitectures. The layout of MSR_LBR_SELECT is the same as Nehalem.
Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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>
Link: http://lkml.kernel.org/r/1460706825-46163-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Kan Liang [Fri, 15 Apr 2016 07:42:47 +0000 (00:42 -0700)]
perf/x86/intel: Add Goldmont CPU support
Add perf core PMU support for Intel Goldmont CPU cores:
- The init code is based on Silvermont.
- There is a new cache event list, based on the Silvermont cache event list.
- Goldmont has 32 LBR entries. It also uses new LBRv6 format, which
report the cycle information using upper 16-bit of the LBR_TO.
- It's recommended to use CPU_CLK_UNHALTED.CORE_P + NPEBS for precise cycles.
For details, please refer to the latest SDM058:
http://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-software-developer-vol-3b-part-2-manual.pdf
Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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>
Link: http://lkml.kernel.org/r/1460706167-45320-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ingo Molnar [Sat, 23 Apr 2016 12:12:10 +0000 (14:12 +0200)]
Merge branch 'perf/urgent' into perf/core, to resolve conflict
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Mon, 4 Apr 2016 07:57:40 +0000 (09:57 +0200)]
perf/core: Make sysctl_perf_cpu_time_max_percent conform to documentation
Markus reported that 0 should also disable the throttling we per
Documentation/sysctl/kernel.txt.
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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>
Fixes:
91a612eea9a3 ("perf/core: Fix dynamic interrupt throttle")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Srinivas Pandruvada [Sun, 17 Apr 2016 15:43:29 +0000 (08:43 -0700)]
perf/x86/intel/rapl: Add missing Haswell model
Added one missing Haswell model.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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: bp@alien8.de
Cc: hpa@zytor.com
Link: http://lkml.kernel.org/r/1460907809-11897-1-git-send-email-srinivas.pandruvada@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andi Kleen [Fri, 15 Apr 2016 20:25:33 +0000 (13:25 -0700)]
perf/x86/intel: Add model number for Skylake Server to perf
Everything the same as base Skylake, just a new model number.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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>
Link: http://lkml.kernel.org/r/1460751933-2264-1-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Arnaldo Carvalho de Melo [Tue, 19 Apr 2016 15:22:25 +0000 (12:22 -0300)]
perf test: Add missing verbose output explaining the reason for failure
One of the branches leading to an error had no debug message emitted,
fix it, the new lines are:
# perf test -v kallsyms
<SNIP>
0xffffffff81001000: diff name v: xen_hypercall_set_trap_table k: hypercall_page
0xffffffff810691f0: diff name v: try_to_free_pud_page k: try_to_free_pmd_page
<SNIP>
0xffffffff8150bb20: diff name v: wakeup_expire_count_show.part.5 k: wakeup_active_count_show.part.7
0xffffffff816bc7f0: diff name v: phys_switch_id_show.part.11 k: phys_port_name_show.part.12
0xffffffff817bbb90: diff name v: __do_softirq k: __softirqentry_text_start
<SNIP>
This in turn exercises another bug, still under investigation, because those
aliases _are_ in kallsyms, with the same name...
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>
Fixes:
ab414dcda8fa ("perf test: Fixup aliases checking in the 'vmlinux matches kallsyms' test")
Link: http://lkml.kernel.org/n/tip-5fhea7a54a54gsmagu9obpr4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Tue, 19 Apr 2016 15:16:55 +0000 (12:16 -0300)]
perf test: Ignore kcore files in the "vmlinux matches kallsyms" test
Before:
# perf test -v kallsyms
<SNIP>
Maps only in vmlinux:
ffffffff81d5e000-
ffffffff81ec3ac8 115e000 [kernel].init.text
ffffffff81ec3ac8-
ffffffffa0000000 12c3ac8 [kernel].exit.text
ffffffffa0000000-
ffffffffa000c000 0 [fjes]
ffffffffa000c000-
ffffffffa0017000 0 [video]
ffffffffa0017000-
ffffffffa001c000 0 [grace]
<SNIP>
ffffffffa0a7f000-
ffffffffa0ba5000 0 [xfs]
ffffffffa0ba5000-
ffffffffffffffff 0 [veth]
Maps in vmlinux with a different name in kallsyms:
Maps only in kallsyms:
ffff880000100000-
ffff88001000b000 80000103000 [kernel.kallsyms]
ffff88001000b000-
ffff880100000000 8001000e000 [kernel.kallsyms]
ffff880100000000-
ffffc90000000000 80100003000 [kernel.kallsyms]
<SNIP>
ffffffffa0000000-
ffffffffff600000 7fffa0003000 [kernel.kallsyms]
ffffffffff600000-
ffffffffffffffff 7fffff603000 [kernel.kallsyms]
test child finished with -1
---- end ----
vmlinux symtab matches kallsyms: FAILED!
#
After:
# perf test -v 1
1: vmlinux symtab matches kallsyms :
--- start ---
test child forked, pid 7058
Looking at the vmlinux_path (8 entries long)
Using /lib/modules/4.6.0-rc1+/build/vmlinux for symbols
0xffffffff81076870: diff end addr for aesni_gcm_dec v: 0xffffffff810791f2 k: 0xffffffff81076902
0xffffffff81079200: diff end addr for aesni_gcm_enc v: 0xffffffff8107bb03 k: 0xffffffff81079292
0xffffffff8107e8d0: diff end addr for aesni_gcm_enc_avx_gen2 v: 0xffffffff81083e76 k: 0xffffffff8107e943
0xffffffff81083e80: diff end addr for aesni_gcm_dec_avx_gen2 v: 0xffffffff81089611 k: 0xffffffff81083ef3
0xffffffff81089990: diff end addr for aesni_gcm_enc_avx_gen4 v: 0xffffffff8108e7c4 k: 0xffffffff81089a03
0xffffffff8108e7d0: diff end addr for aesni_gcm_dec_avx_gen4 v: 0xffffffff810937ef k: 0xffffffff8108e843
Maps only in vmlinux:
ffffffff81d5e000-
ffffffff81ec3ac8 115e000 [kernel].init.text
ffffffff81ec3ac8-
ffffffffa0000000 12c3ac8 [kernel].exit.text
Maps in vmlinux with a different name in kallsyms:
Maps only in kallsyms:
test child finished with -1
---- end ----
vmlinux symtab matches kallsyms: FAILED!
#
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>
Fixes:
8e0cf965f95e ("perf symbols: Add support for reading from /proc/kcore")
Link: http://lkml.kernel.org/n/tip-n6vrwt9t89w8k769y349govx@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Tue, 19 Apr 2016 15:12:49 +0000 (12:12 -0300)]
perf symbols: Allow loading kallsyms without considering kcore files
Before the support for using /proc/kcore was introduced, the kallsyms
routines used /proc/modules and the first 'perf test' entry expected
finding maps for each module in the system, which is not the case with
the kcore code. Provide a way to ignore kcore files so that the test can
have its expectations met.
Improving the test to cover kcore files as well needs to be done.
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-ek5urnu103dlhfk4l6pcw041@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Tue, 19 Apr 2016 15:01:51 +0000 (12:01 -0300)]
perf build: Remove x86 references from arch-neutral Build
It will already be dealt with generating the syscalltbl.c file in the
x86 arch specific Build files, namely via 'archheaders'.
This fixes the build on !x86 arches, as reported for powerpcle
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes:
1b700c997500 ("perf tools: Build syscall table .c header from kernel's syscall_64.tbl")
Link: http://lkml.kernel.org/r/20160415212831.GT9056@kernel.org
[ Removed the syscalltbl.o altogether, as per Jiri's suggestion ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Colin Ian King [Mon, 18 Apr 2016 23:07:18 +0000 (00:07 +0100)]
perf jit: memset() variable 'st' using the correct size
The current code is memsetting the 'struct stat' variable 'st' with the size of
'stat' (which turns out to be 1 byte) rather than the size of variable 'sz'.
Committer notes:
sizeof(function) isn't valid, the result depends on the compiler used, with
gcc, enabling pedantic warnings we get:
$ cat sizeof_function.c
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdio.h>
int main(void)
{
printf("sizeof(stat)=%zd, stat=%p\n", sizeof(stat), stat);
return 0;
}
$ readelf -sW sizeof_function | grep -w stat
49:
0000000000400630 16 FUNC WEAK HIDDEN 13 stat
$ cc -pedantic sizeof_function.c -o sizeof_function
sizeof_function.c: In function ‘main’:
sizeof_function.c:8:46: warning: invalid application of ‘sizeof’ to a function type [-Wpointer-arith]
printf("sizeof(stat)=%zd, stat=%p\n", sizeof(stat), stat);
^
$ ./sizeof_function
sizeof(stat)=1, stat=0x400630
$
Standard C, section 6.5.3.4:
"The sizeof operator shall not be applied to an expression that has function
type or an incomplete type, to the parenthesized name of such a type,
or to an expression that designates a bit-field member."
http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1256.pdf
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Fixes:
9b07e27f88b9 ("perf inject: Add jitdump mmap injection support")
Link: http://lkml.kernel.org/r/1461020838-9260-1-git-send-email-colin.king@canonical.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Chris Phlipot [Tue, 19 Apr 2016 08:56:02 +0000 (01:56 -0700)]
perf script: Fix postgresql ubuntu install instructions
The current instructions for setting up an Ubuntu system for using the
export-to-postgresql.py script are incorrect.
The instructions in the script have been updated to work on newer
versions of ubuntu.
-Add missing dependencies to apt-get command:
python-pyside.qtsql, libqt4-sql-psql
-Add '-s' option to createuser command to force the user to be a
superuser since the command doesn't prompt as indicated in the
current instructions.
Tested on: Ubuntu 14.04, Ubuntu 16.04(beta)
Signed-off-by: Chris Phlipot <cphlipot0@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1461056164-14914-3-git-send-email-cphlipot0@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Ingo Molnar [Tue, 19 Apr 2016 06:41:59 +0000 (08:41 +0200)]
Merge tag 'perf-urgent-for-mingo-
20160418' of git://git./linux/kernel/git/acme/linux into perf/urgent
Pull a perf/urgent fix from Arnaldo Carvalho de Melo:
- Fix segfault tracing transactions in Intel PT (Adrian Hunter)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Arnaldo Carvalho de Melo [Mon, 18 Apr 2016 15:30:16 +0000 (12:30 -0300)]
perf top: Use callchain_param.enabled instead of symbol_conf.use_callchain
One more step in the direction of using just callchain_param for
callchain parameters.
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-3b1o9kb2dc94zldz0klckti6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Mon, 18 Apr 2016 15:24:41 +0000 (12:24 -0300)]
perf hists browser: Fold two consecutive symbol_conf.use_callchain ifs
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-u701i6qpecgm9jiat52i8l98@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Mon, 18 Apr 2016 15:09:08 +0000 (12:09 -0300)]
perf tools: Ditch record_opts.callgraph_set
We have callchain_param.enabled for that.
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-silwqjc2t25ls42dsvg28pp5@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Mon, 18 Apr 2016 14:54:31 +0000 (11:54 -0300)]
perf report: Use callchain_param.enabled instead of tool specific knob
We have callchain_param.enabled, so no need to have something just for
'perf report' to do the same thing.
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-wbeisubpualwogwi5u8utnt1@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Mon, 18 Apr 2016 14:53:07 +0000 (11:53 -0300)]
perf callchain: Set callchain_param.enabled when parsing --call-graph
Trying to move in the direction of using callchain_param for all
callchain parameters, eventually ditching them from symbol_conf.
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-kixllia6r26mz45ng056zq7z@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Mon, 18 Apr 2016 14:31:46 +0000 (11:31 -0300)]
perf script: Check sample->callchain before using it
Found by code inspection, while looking at thread__resolve_callchain()
callsites, one had it, the other didn't.
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-6r8i2afd3523thuuaxl39yhk@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Mon, 18 Apr 2016 13:35:03 +0000 (10:35 -0300)]
perf evsel: Add missign class prefix to has_branch_stack method
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-5i07ivw1yjsweb7gztr255jd@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adrian Hunter [Mon, 18 Apr 2016 10:57:48 +0000 (13:57 +0300)]
perf intel-pt: Fix segfault tracing transactions
Tracing a workload that uses transactions gave a seg fault as follows:
perf record -e intel_pt// workload
perf report
Program received signal SIGSEGV, Segmentation fault.
0x000000000054b58c in intel_pt_reset_last_branch_rb (ptq=0x1a36110)
at util/intel-pt.c:929
929 ptq->last_branch_rb->nr = 0;
(gdb) p ptq->last_branch_rb
$1 = (struct branch_stack *) 0x0
(gdb) up
1148 intel_pt_reset_last_branch_rb(ptq);
(gdb) l
1143 if (ret)
1144 pr_err("Intel Processor Trace: failed to deliver transaction event
1145 ret);
1146
1147 if (pt->synth_opts.callchain)
1148 intel_pt_reset_last_branch_rb(ptq);
1149
1150 return ret;
1151 }
1152
(gdb) p pt->synth_opts.callchain
$2 = true
(gdb)
(gdb) bt
#0 0x000000000054b58c in intel_pt_reset_last_branch_rb (ptq=0x1a36110)
#1 0x000000000054c1e0 in intel_pt_synth_transaction_sample (ptq=0x1a36110)
#2 0x000000000054c5b2 in intel_pt_sample (ptq=0x1a36110)
Caused by checking the 'callchain' flag when it should have been the
'last_branch' flag. Fix that.
Reported-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org # v4.4+
Fixes:
f14445ee72c5 ("perf intel-pt: Support generating branch stack")
Link: http://lkml.kernel.org/r/1460977068-11566-1-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linus Torvalds [Mon, 18 Apr 2016 02:13:32 +0000 (19:13 -0700)]
Linux 4.6-rc4
Linus Torvalds [Sun, 17 Apr 2016 19:30:06 +0000 (12:30 -0700)]
Merge tag 'dm-4.6-fix-2' of git://git./linux/kernel/git/device-mapper/linux-dm
Pull device mapper fix from Mike Snitzer:
"Fix for earlier 4.6-rc4 stable@ commit that introduced improper use of
write lock in cmd_read_lock() -- due to cut-n-paste gone awry (and
sparse didn't catch it)"
* tag 'dm-4.6-fix-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm cache metadata: fix cmd_read_lock() acquiring write lock
Ahmed Samy [Sun, 17 Apr 2016 05:37:09 +0000 (05:37 +0000)]
dm cache metadata: fix cmd_read_lock() acquiring write lock
Commit
9567366fefdd ("dm cache metadata: fix READ_LOCK macros and
cleanup WRITE_LOCK macros") uses down_write() instead of down_read() in
cmd_read_lock(), yet up_read() is used to release the lock in
READ_UNLOCK(). Fix it.
Fixes:
9567366fefdd ("dm cache metadata: fix READ_LOCK macros and cleanup WRITE_LOCK macros")
Cc: stable@vger.kernel.org
Signed-off-by: Ahmed Samy <f.fallen45@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Linus Torvalds [Sun, 17 Apr 2016 03:59:06 +0000 (20:59 -0700)]
Merge tag 'char-misc-4.6-rc4' of git://git./linux/kernel/git/gregkh/char-misc
Pull char/misc fixes from Greg KH:
"Here are some small char/misc driver fixes for 4.6-rc4. Full details
are in the shortlog, nothing major here.
These have all been in linux-next for a while with no reported issues"
* tag 'char-misc-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
lkdtm: do not leak free page on kmalloc failure
lkdtm: fix memory leak of base
lkdtm: fix memory leak of val
extcon: palmas: Drop stray IRQF_EARLY_RESUME flag
Linus Torvalds [Sun, 17 Apr 2016 03:53:50 +0000 (20:53 -0700)]
Merge tag 'driver-core-4.6-rc4' of git://git./linux/kernel/git/gregkh/driver-core
Pull misc fixes from Greg KH:
"Here are three small fixes for 4.6-rc4.
Two fix up some lz4 issues with big endian systems, and the remaining
one resolves a minor debugfs issue that was reported.
All have been in linux-next with no reported issues"
* tag 'driver-core-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
lib: lz4: cleanup unaligned access efficiency detection
lib: lz4: fixed zram with lz4 on big endian machines
debugfs: Make automount point inodes permanently empty
Linus Torvalds [Sun, 17 Apr 2016 03:48:14 +0000 (20:48 -0700)]
Merge tag 'usb-4.6-rc4' of git://git./linux/kernel/git/gregkh/usb
Pull USB driver fixes from Greg KH:
"Here are some small USB fixes for 4.6-rc4.
Mostly xhci fixes for reported issues, a UAS bug that has hit a number
of people, including stable tree users, and a few other minor things.
All have been in linux-next for a while with no reported issues"
* tag 'usb-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
usb: hcd: out of bounds access in for_each_companion
USB: uas: Add a new NO_REPORT_LUNS quirk
USB: uas: Limit qdepth at the scsi-host level
doc: usb: Fix typo in gadget_multi documentation
usb: host: xhci-plat: Make enum xhci_plat_type start at a non zero value
xhci: fix 10 second timeout on removal of PCI hotpluggable xhci controllers
usb: xhci: fix wild pointers in xhci_mem_cleanup
usb: host: xhci-plat: fix cannot work if R-Car Gen2/3 run on above 4GB phys
usb: host: xhci: add a new quirk XHCI_NO_64BIT_SUPPORT
xhci: resume USB 3 roothub first
usb: xhci: applying XHCI_PME_STUCK_QUIRK to Intel BXT B0 host
cdc-acm: fix crash if flushed with nothing buffered
Linus Torvalds [Sat, 16 Apr 2016 22:52:38 +0000 (15:52 -0700)]
Merge tag 'dmaengine-fix-4.6-rc4' of git://git.infradead.org/users/vkoul/slave-dma
Pull dmaengine fixes from Vinod Koul:
"This time we have some odd fixes in hsu, edma, omap and xilinx.
Usual fixes and nothing special"
* tag 'dmaengine-fix-4.6-rc4' of git://git.infradead.org/users/vkoul/slave-dma:
dmaengine: dw: fix master selection
dmaengine: edma: special case slot limit workaround
dmaengine: edma: Remove dynamic TPTC power management feature
dmaengine: vdma: don't crash when bad channel is requested
dmaengine: omap-dma: Do not suppress interrupts for memcpy
dmaengine: omap-dma: Fix polled channel completion detection and handling
dmaengine: hsu: correct use of channel status register
dmaengine: hsu: correct residue calculation of active descriptor
dmaengine: hsu: set HSU_CH_MTSR to memory width
Linus Torvalds [Sat, 16 Apr 2016 22:43:19 +0000 (15:43 -0700)]
Merge branch 'locking-urgent-for-linus' of git://git./linux/kernel/git/tip/tip
Pull locking fixlet from Ingo Molnar:
"Fixes a build warning on certain Kconfig combinations"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/lockdep: Fix print_collision() unused warning
Linus Torvalds [Sat, 16 Apr 2016 22:37:05 +0000 (15:37 -0700)]
Merge branch 'efi-urgent-for-linus' of git://git./linux/kernel/git/tip/tip
Pull EFI fix from Ingo Molnar:
"An arm64 boot crash fix"
* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi/arm64: Don't apply MEMBLOCK_NOMAP to UEFI memory map mapping
Vinod Koul [Sat, 16 Apr 2016 17:22:03 +0000 (22:52 +0530)]
Merge branch 'fix/edma' into fixes
Vinod Koul [Sat, 16 Apr 2016 17:15:26 +0000 (22:45 +0530)]
Merge branch 'fix/xilinx' into fixes
Vinod Koul [Sat, 16 Apr 2016 17:15:17 +0000 (22:45 +0530)]
Merge branch 'fix/omap' into fixes
Vinod Koul [Sat, 16 Apr 2016 17:14:32 +0000 (22:44 +0530)]
Merge branch 'fix/hsu' into fixes
Arnaldo Carvalho de Melo [Sat, 16 Apr 2016 12:36:32 +0000 (09:36 -0300)]
perf trace: Fix build when DWARF unwind isn't available
The variable is initialized and then conditionally set to a different
value, but not used when DWARF unwinding is not available, bummer, write
1000 times: "Run make -C tools/perf build-test"...
builtin-trace.c: In function ‘cmd_trace’:
builtin-trace.c:3112:6: error: variable ‘max_stack_user_set’ set but not
used [-Werror=unused-but-set-variable]
bool max_stack_user_set = true;
^
cc1: all warnings being treated as err
Fix it by marking it as __maybe_unused.
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>
Fixes:
056149932602 ("perf trace: Make --(min,max}-stack imply "--call-graph dwarf"")
Link: http://lkml.kernel.org/n/tip-85r40c5hhv6jnmph77l1hgsr@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Ingo Molnar [Sat, 16 Apr 2016 09:09:57 +0000 (11:09 +0200)]
Merge tag 'perf-core-for-mingo-
20160415' of git://git./linux/kernel/git/acme/linux into perf/core
Pull perf/core improvements from Arnaldo Carvalho de Melo:
User visible changes:
- Wire the callchain unwinding "max-stack" now to 'perf script --max-stack',
allowing to limit the depth of callchains, possibly reducing processing
time (Arnaldo Carvalho de Melo)
- Ditto for 'perf trace --max-stack' (Arnaldo Carvalho de Melo)
- Introduce a --min-stack filter for 'perf trace', to show syscalls that
had a userspace callchain leading to it at least min-stack deep (Arnaldo Carvalho de Melo)
- Make 'perf trace' work with multiple threads and the --duration filter,
i.e. do not print the start of an interrupted syscall followed by ...
to print interrupts from other threads, as we need to wait the sys_exit
syscall tracepoint to calculate the duration, duh. (Arnaldo Carvalho de Melo)
System wide --duration now works as expected:
[root@jouet ~]# trace --duration 100
152.393 (145.147 ms): Timer/24358 futex(uaddr: 0x7f5ed98e56cc, op: WAIT_BITSET|PRIV|CLKRT, val:
7055125, utime: 0x7f5ecdbfec30, val3:
4294967295) = -1 ETIMEDOUT Connection timed out
152.438 (145.040 ms): firefox/24321 poll(ufds: 0x7f5ec388b460, nfds: 6, timeout_msecs:
4294967295) = 1
358.580 (158.279 ms): Xorg/2025 select(n: 512, inp: 0x83a8e0, tvp: 0x7ffdcbb63610) = 0 Timeout
358.687 (148.285 ms): gnome-terminal/2711 poll(ufds: 0x55b7e6811ad0, nfds: 15, timeout_msecs: 249) = 1
370.150 (169.569 ms): gnome-shell/2287 poll(ufds: 0x55e623d65490, nfds: 86, timeout_msecs:
4294967295) = 1
- Now 'perf trace's --max-stack and --min-stack will automatically set
"--call-graph dwarf", if --call-graph is not present on the command line:
[root@jouet ~]# perf trace -e nanosleep --max-stack 3 usleep 1
0.299 ( 0.057 ms): usleep/29658 nanosleep(rqtp: 0x7fff80f3b230) = 0
__nanosleep+0x10 (/usr/lib64/libc-2.22.so)
usleep+0x34 (/usr/lib64/libc-2.22.so)
main+0x1eb (/usr/bin/usleep)
[root@jouet ~]#
- Bump 'perf trace --mmap-pages' for root when using callchains and not
specifying --mmap-pages explicitely (Arnaldo Carvalho de Melo)
Build fixes:
- The python binding object had missing symbols, to some refactoring
to fix that (Arnaldo Carvalho de Melo)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Linus Torvalds [Fri, 15 Apr 2016 22:44:10 +0000 (15:44 -0700)]
Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"A few fixes for the current series. This contains:
- Two fixes for NVMe:
One fixes a reset race that can be triggered by repeated
insert/removal of the module.
The other fixes an issue on some platforms, where we get probe
timeouts since legacy interrupts isn't working. This used not to
be a problem since we had the worker thread poll for completions,
but since that was killed off, it means those poor souls can't
successfully probe their NVMe device. Use a proper IRQ check and
probe (msi-x -> msi ->legacy), like most other drivers to work
around this. Both from Keith.
- A loop corruption issue with offset in iters, from Ming Lei.
- A fix for not having the partition stat per cpu ref count
initialized before sending out the KOBJ_ADD, which could cause user
space to access the counter prior to initialization. Also from
Ming Lei.
- A fix for using the wrong congestion state, from Kaixu Xia"
* 'for-linus' of git://git.kernel.dk/linux-block:
block: loop: fix filesystem corruption in case of aio/dio
NVMe: Always use MSI/MSI-x interrupts
NVMe: Fix reset/remove race
writeback: fix the wrong congested state variable definition
block: partition: initialize percpuref before sending out KOBJ_ADD
Linus Torvalds [Fri, 15 Apr 2016 22:34:27 +0000 (15:34 -0700)]
Merge branch 'libnvdimm-fixes' of git://git./linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm fixes from Ross Zwisler:
"Two fixes:
- Fix memcpy_from_pmem() to fallback to memcpy() for architectures
where CONFIG_ARCH_HAS_PMEM_API=n.
- Add a comment explaining why we write data twice when clearing
poison in pmem_do_bvec().
This has passed a boot test on an X86_32 config, which was the
architecture where issue #1 above was first noticed"
Dan Williams adds:
"We're giving this multi-maintainer setup a shot, so expect libnvdimm
pull requests from either Ross or I going forward"
* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
libnvdimm, pmem: clarify the write+clear_poison+write flow
pmem: fix BUG() error in pmem.h:48 on X86_32
Linus Torvalds [Fri, 15 Apr 2016 22:25:09 +0000 (15:25 -0700)]
Merge tag 'for-linus-
20160415' of git://git.infradead.org/linux-mtd
Pull MTD fix from Brian Norris:
"One MTD fix for v4.6-rc4:
In the v4.4 cycle, we relaxed the requirement for assigning
mtd->owner, but we didn't remove this error case. It's hit only
by drivers that are both:
(a) using nand_scan() directly
and
(b) built as modules
We haven't seen explicit complaints about this (most use cases don't
fit one or both of the above), but we should definitely not be
BUG()'ing here"
* tag 'for-linus-
20160415' of git://git.infradead.org/linux-mtd:
mtd: nand: Drop mtd.owner requirement in nand_scan
Linus Torvalds [Fri, 15 Apr 2016 22:10:32 +0000 (15:10 -0700)]
Merge tag 'mmc-v4.6-rc3' of git://git.linaro.org/people/ulf.hansson/mmc
Pull MMC fixes from Ulf Hansson:
"Here are a couple of mmc fixes intended for v4.6 rc4.
Regarding the fix for the regression about mmcblk device indexes. The
approach taken to solve the problem seems to be good enough. There
were some discussions around the solution, but it seems like people
were happy about it in the end.
MMC core:
- Restore similar old behaviour when assigning mmcblk device indexes
MMC host:
- tegra: Disable UHS-I modes for Tegra124 to fix regression"
* tag 'mmc-v4.6-rc3' of git://git.linaro.org/people/ulf.hansson/mmc:
mmc: tegra: Disable UHS-I modes for Tegra124
mmc: block: Use the mmc host device index as the mmcblk device index
Linus Torvalds [Fri, 15 Apr 2016 21:59:28 +0000 (14:59 -0700)]
Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
"This contains fixes for exynos, amdgpu, radeon, i915 and qxl.
It also contains some fixes to the core drm edid parser.
qxl:
- fix for a cursor hotspot issue
radeon:
- some MST fixes that I've been running locally and make my monitor a
bit happier
exynos:
- fix some regressions and build fixes
amdgpu:
- a couple of small fixes
i915:
- two DP MST fixes and a couple of other regression fixes
Nothing too out of the ordinary or surprising at this point"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/exynos: Use VIDEO_SAMSUNG_S5P_G2D=n as G2D Kconfig dependency
drm/exynos: fix a warning message
drm/exynos: mic: fix an error code
drm/exynos: fimd: fix broken dp_clock control
drm/exynos: build fbdev code conditionally
drm/exynos: fix adjusted_mode pointer in exynos_plane_mode_set
drm/exynos: fix error handling in exynos_drm_subdrv_open
drm/amd/amdgpu: fix irq domain remove for tonga ih
drm/i915: fix deadlock on lid open
drm/radeon: use helper for mst connector dpms.
drm/radeon/mst: port some MST setup code from DAL.
drm/amdgpu: add invisible pin size statistic
drm/edid: Fix DMT 1024x768@43Hz (interlaced) timings
drm/i915: Exit cherryview_irq_handler() after one pass
drm/i915: Call intel_dp_mst_resume() before resuming displays
drm/i915: Fix race condition in intel_dp_destroy_mst_connector()
drm/edid: Fix parsing of EDID 1.4 Established Timings III descriptor
drm/edid: Fix EDID Established Timings I and II
drm/qxl: fix cursor position with non-zero hotspot
Linus Torvalds [Fri, 15 Apr 2016 21:51:45 +0000 (14:51 -0700)]
Merge branch 'parisc-4.6-4' of git://git./linux/kernel/git/deller/parisc-linux
Pull parisc ftrace fixes from Helge Deller:
"This is (most likely) the last pull request for v4.6 for the parisc
architecture.
It fixes the FTRACE feature for parisc, which is horribly broken since
quite some time and doesn't even compile. This patch just fixes the
bare minimum (it actually removes more lines than it adds), so that
the function tracer works again on 32- and 64bit kernels.
I've queued up additional patches on top of this patch which e.g. add
the syscall tracer, but those have to wait for the merge window for
v4.7."
* 'parisc-4.6-4' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Fix ftrace function tracer
Dan Williams [Fri, 15 Apr 2016 02:40:47 +0000 (19:40 -0700)]
libnvdimm, pmem: clarify the write+clear_poison+write flow
The ACPI specification does not specify the state of data after a clear
poison operation. Potential future libnvdimm bus implementations for
other architectures also might not specify or disagree on the state of
data after clear poison. Clarify why we write twice.
Reported-by: Jeff Moyer <jmoyer@redhat.com>
Reported-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Arnaldo Carvalho de Melo [Fri, 15 Apr 2016 20:52:34 +0000 (17:52 -0300)]
perf trace: Bump --mmap-pages when --call-graph is used by the root user
To reduce the chances we'll overflow the mmap buffer, manual fine tuning
trumps this.
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-wxygbxmp1v9mng1ea28wet02@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
projects / GitHub / LineageOS / android_kernel_motorola_exynos9610.git / log