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  1. 08 Jan, 2018 15 commits
    • Jiri Olsa's avatar
      perf: Allocate context task_ctx_data for child event · 313ccb96
      Jiri Olsa authored 
      Currently we use perf_event_context::task_ctx_data to save and restore
the LBR status when the task is scheduled out and in.

We don't allocate it for child contexts, which results in shorter task's
LBR stack, because we don't save the history from previous run and start
over every time we schedule the task in.

I made a test to generate samples with LBR call stack and got higher
numbers on bigger chain depths:

                            before:     after:
  LBR call chain: nr: 1       60561     498127
  LBR call chain: nr: 2           0          0
  LBR call chain: nr: 3      107030       2172
  LBR call chain: nr: 4      466685      62758
  LBR call chain: nr: 5     2307319     878046
  LBR call chain: nr: 6       48713     495218
  LBR call chain: nr: 7        1040       4551
  LBR call chain: nr: 8         481        172
  LBR call chain: nr: 9         878        120
  LBR call chain: nr: 10       2377       6698
  LBR call chain: nr: 11      28830     151487
  LBR call chain: nr: 12      29347     339867
  LBR call chain: nr: 13          4         22
  LBR call chain: nr: 14          3         53
Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Fixes: 4af57ef2 ("perf: Add pmu specific data for perf task context")
Link: http://lkml.kernel.org/r/20180107160356.28203-4-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      313ccb96
    • Jiri Olsa's avatar
      perf tools: Display perf_event_attr::namespaces debug info · db9fc765
      Jiri Olsa authored 
      Display namespaces bit in -vv debug display:

  $ perf record -vv --namespaces ...
  ...
  perf_event_attr:
    size                             112
    ...
    namespaces                       1
Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180107160356.28203-3-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      db9fc765
    • Jiri Olsa's avatar
      perf tools: Enable LIBBABELTRACE by default · 24787afb
      Jiri Olsa authored 
      There's no reason anymore to treat babel trace in a special way, because
a) we no longer display its state b) the needed babeltrace library is
now out and well adopted among distros.
Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180107160356.28203-2-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      24787afb
    • Jin Yao's avatar
      perf script: Support time percent and multiple time ranges · 2ab046cd
      Jin Yao authored 
      perf script has a --time option to limit the time range of output.  It
only supports absolute time.

Now this option is extended to support multiple time ranges and support
the percent of time.

For example:

1. Select the first and second 10% time slices:

   perf script --time 10%/1,10%/2

2. Select from 0% to 10% and 30% to 40% slices:

   perf script --time 0%-10%,30%-40%

Changelog:

v6: Fix the merge issue with latest perf/core branch.
    No functional changes.

v5: Add checking of first/last sample time to detect if it's recorded
    in perf.data. If it's not recorded, returns error message to user.

v4: Remove perf_time__skip_sample, only uses perf_time__ranges_skip_sample

v3: Since the definitions of first_sample_time/last_sample_time
    are moved from perf_session to perf_evlist so change the
    related code.
Signed-off-by: default avatarJin Yao <yao.jin@linux.intel.com>
Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1512738826-2628-7-git-send-email-yao.jin@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      2ab046cd
    • Jin Yao's avatar
      perf report: Support time percent and multiple time ranges · 5b969bc7
      Jin Yao authored 
      perf report has a --time option to limit the time range of output.  It
only supports absolute time.

Now this option is extended to support multiple time ranges and support
the percent of time.

For example:

1. Select the first and second 10% time slices:

perf report --time 10%/1,10%/2

2. Select from 0% to 10% and 30% to 40% slices:

perf report --time 0%-10%,30%-40%

Changelog:

v6: Fix the merge issue with latest perf/core branch.
    No functional changes.

v5: Add checking of first/last sample time to detect if it's recorded
    in perf.data. If it's not recorded, returns error message to user.

v4: Remove perf_time__skip_sample, only uses perf_time__ranges_skip_sample

v3: Since the definitions of first_sample_time/last_sample_time
    are moved from perf_session to perf_evlist so change the
    related code.
Signed-off-by: default avatarJin Yao <yao.jin@linux.intel.com>
Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1512738826-2628-6-git-send-email-yao.jin@linux.intel.com
[ Add missing colons at end of examples in the man page ]
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      5b969bc7
    • Jin Yao's avatar
      perf tools: Create function to perform multiple time range checking · 9a9b8b4b
      Jin Yao authored 
      Previous patch supports the multiple time range.

For example, select the first and second 10% time slices.
perf report --time 10%/1,10%/2

We need a function to check if a timestamp is in the ranges of
[0, 10%) and [10%, 20%].

Note that it includes the last element in [10%, 20%] but it doesn't
include the last element in [0, 10%). It's to avoid the overlap.

This patch implments a new function perf_time__ranges_skip_sample
for this checking.

Change log:

v4: Let perf_time__ranges_skip_sample be compatible with
    perf_time__skip_sample when only one time range.
Signed-off-by: default avatarJin Yao <yao.jin@linux.intel.com>
Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1512738826-2628-5-git-send-email-yao.jin@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      9a9b8b4b
    • Jin Yao's avatar
      perf tools: Create function to parse time percent · 13a70f35
      Jin Yao authored 
      Current perf report/script/... have a --time option to limit the time
range of output. But right now it only supports absolute time, add
support for time percentage.

For example:

1. Select the second 10% time slice
   perf report --time 10%/2

2. Select from 0% to 10% time slice
   perf report --time 0%-10%

It also support the multiple time ranges.

3. Select the first and second 10% time slices
   perf report --time 10%/1,10%/2

4. Select from 0% to 10% and 30% to 40% slices
   perf report --time 0%-10%,30%-40%

Changelog:

v4: An issue is found. Following passes.
    perf script --time 10%/10x12321xsdfdasfdsafdsafdsa

    Now it uses strtol to replace atoi.

Committer notes:

This just puts in place the infrastructure, so the examples in this cset
comment will only work later, after more patches in this series are
applied.
Signed-off-by: default avatarJin Yao <yao.jin@linux.intel.com>
Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1512738826-2628-4-git-send-email-yao.jin@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      13a70f35
    • Jin Yao's avatar
      perf record: Record the first and last sample time in the header · 68588baf
      Jin Yao authored 
      In the default 'perf record' configuration, all samples are processed,
to create the HEADER_BUILD_ID table. So it's very easy to get the
first/last samples and save the time to perf file header via the
function write_sample_time().

Later, at post processing time, perf report/script will fetch the time
from perf file header.

Committer testing:

  # perf record -a sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 2.099 MB perf.data (1101 samples) ]
  [root@jouet home]# perf report --header | grep "time of "
  # time of first sample : 22947.909226
  # time of last sample : 22948.910704
  #
  # perf report -D | grep PERF_RECORD_SAMPLE\(
  0 22947909226101 0x20bb68 [0x30]: PERF_RECORD_SAMPLE(IP, 0x4001): 0/0: 0xffffffffa21b1af3 period: 1 addr: 0
  0 22947909229928 0x20bb98 [0x30]: PERF_RECORD_SAMPLE(IP, 0x4001): 0/0: 0xffffffffa200d204 period: 1 addr: 0
  <SNIP>
  3 22948910397351 0x219360 [0x30]: PERF_RECORD_SAMPLE(IP, 0x4001): 28251/28251: 0xffffffffa22071d8 period: 169518 addr: 0
  0 22948910652380 0x20f120 [0x30]: PERF_RECORD_SAMPLE(IP, 0x4001): 0/0: 0xffffffffa2856816 period: 198807 addr: 0
  2 22948910704034 0x2172d0 [0x30]: PERF_RECORD_SAMPLE(IP, 0x4001): 0/0: 0xffffffffa2856816 period: 88111 addr: 0
  #

Changelog:

v7: Just update the patch description according to Arnaldo's suggestion.

v6: Currently '--buildid-all' is not enabled at default. So the walking
    on all samples is the default operation. There is no big overhead
    to calculate the timestamp boundary in process_sample_event handler
    once we already go through all samples. So the timestamp boundary
    calculation is enabled by default when '--buildid-all' is not enabled.

    While if '--buildid-all' is enabled, we creates a new option
    "--timestamp-boundary" for user to decide if it enables the
    timestamp boundary calculation.

v5: There is an issue that the sample walking can only work when
    '--buildid-all' is not enabled. So we need to let the walking
    be able to work even if '--buildid-all' is enabled and let the
    processing skips the dso hit marking for this case.

    At first, I want to provide a new option "--record-time-boundaries".
    While after consideration, I think a new option is not very
    necessary.

v3: Remove the definitions of first_sample_time and last_sample_time
    from struct record and directly save them in perf_evlist.
Signed-off-by: default avatarJin Yao <yao.jin@linux.intel.com>
Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1512738826-2628-3-git-send-email-yao.jin@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      68588baf
    • Jin Yao's avatar
      perf header: Add infrastructure to record first and last sample time · 6011518d
      Jin Yao authored 
      perf report/script/... have a --time option to limit the time range of
output. That's very useful to slice large traces, e.g. when processing
the output of perf script for some analysis.

But right now --time only supports absolute time. Also there is no fast
way to get the start/end times of a given trace except for looking at
it.  This makes it hard to e.g. only decode the first half of the trace,
which is useful for parallelization of scripts

Another problem is that perf records are variable size and there is no
synchronization mechanism. So the only way to find the last sample
reliably would be to walk all samples. But we want to avoid that in perf
report/...  because it is already quite expensive. That is why storing
the first sample time and last sample time in perf record is better.

This patch creates a new header feature type HEADER_SAMPLE_TIME and
related ops. Save the first sample time and the last sample time to the
feature section in perf file header. That will be done when, for
instance, processing build-ids, where we already have to process all
samples to create the build-id table, take advantage of that to further
amortize that processing by storing HEADER_SAMPLE_TIME to make 'perf
report/script' faster when using --time.

Committer testing:

After this patch is applied the header is written with zeroes, we need
the next patch, for "perf record" to actually write the timestamps:

  # perf report -D | grep PERF_RECORD_SAMPLE\(
  22501155244406 0x44f0 [0x28]: PERF_RECORD_SAMPLE(IP, 0x4001): 25016/25016: 0xffffffffa21be8c5 period: 1 addr: 0
  <SNIP>
  22501155793625 0x4a30 [0x28]: PERF_RECORD_SAMPLE(IP, 0x4001): 25016/25016: 0xffffffffa21ffd50 period: 2828043 addr: 0
  # perf report --header | grep "time of "
  # time of first sample : 0.000000
  # time of last sample : 0.000000
  #

Changelog:

v7: 1. Rebase to latest perf/core branch.

    2. Add following clarification in patch description according to
       Arnaldo's suggestion.

       "That will be done when, for instance, processing build-ids,
	where we already have to process all samples to create the
	build-id table, take advantage of that to further amortize
	that processing by storing HEADER_SAMPLE_TIME to make
	'perf report/script' faster when using --time."

v4: Use perf script time style for timestamp printing. Also add with
    the printing of sample duration.

v3: Remove the definitions of first_sample_time/last_sample_time from
    perf_session. Just define them in perf_evlist
Signed-off-by: default avatarJin Yao <yao.jin@linux.intel.com>
Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1512738826-2628-2-git-send-email-yao.jin@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      6011518d
    • Jin Yao's avatar
      perf report: Fix a no annotate browser displayed issue · 40c39e30
      Jin Yao authored 
      When enabling '-b' option in perf record, for example,

  perf record -b ...
  perf report

and then browsing the annotate browser from perf report (press 'A'), it
would fail (annotate browser can't be displayed).

It's because the '.add_entry_cb' op of struct report is overwritten by
hist_iter__branch_callback() in builtin-report.c. But this function doesn't do
something like mapping symbols and sources. So next, do_annotate() will return
directly.

        notes = symbol__annotation(act->ms.sym);
        if (!notes->src)
                return 0;

This patch adds the lost code to hist_iter__branch_callback (refer to
hist_iter__report_callback).

v2:

Fix a crash bug when perform 'perf report --stdio'.

The reason is that we init the symbol annotation only in browser mode, it
doesn't allocate/init resources for stdio mode.

So now in hist_iter__branch_callback(), it will return directly if it's not in
browser mode.
Signed-off-by: default avatarJin Yao <yao.jin@linux.intel.com>
Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1514284963-18587-1-git-send-email-yao.jin@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      40c39e30
    • Jin Yao's avatar
      perf report: Fix a wrong offset issue when using /proc/kcore · 935f5a9d
      Jin Yao authored 
      When a valid vmlinux is not found, 'perf report' falls back to look at
/proc/kcore. In this case, it will report the impossible large offset.

For example:

  # perf record -b -e cycles:k find /etc/ > /dev/null
  # perf report --stdio --branch-history

    22.77%  _vm_normal_page+18446603336221188162
            |
            ---page_remove_rmap +18446603336221188324
               page_remove_rmap +18446603336221188487 (cycles:5)
               unlock_page_memcg +18446603336221188096
               page_remove_rmap +18446603336221188327 (cycles:1)

The issue is the value which is passed to parameter 'addr' in
__get_srcline() is the objdump address. It's not correct if we calculate
the offset by using 'addr - sym->start'.

This patch creates a new parameter 'ip' in __get_srcline(). It is not
converted to objdump address.

With this patch, the perf report output is:

    22.77%  _vm_normal_page+66
            |
            ---page_remove_rmap +228
               page_remove_rmap +391 (cycles:5)
               unlock_page_memcg +0
               page_remove_rmap +231 (cycles:1)
               page_remove_rmap +236

Committer testing:

Make sure you get any valid vmlinux out of the way, using '-v' on the
'perf report' case and deleting it from places where perf searches them,
like your kernel build dir and the build-id cache, in ~/.debug/.
Reported-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: default avatarJin Yao <yao.jin@linux.intel.com>
Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1514564812-17344-1-git-send-email-yao.jin@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      935f5a9d
    • Wang Nan's avatar
      perf tools: Fix compile error with libunwind x86 · 44df1afd
      Wang Nan authored 
      Fix a compile error:

 ...
   CC       util/libunwind/x86_32.o
 In file included from util/libunwind/x86_32.c:33:0:
 util/libunwind/../../arch/x86/util/unwind-libunwind.c: In function 'libunwind__x86_reg_id':
 util/libunwind/../../arch/x86/util/unwind-libunwind.c:110:11: error: 'EINVAL' undeclared (first use in this function)
    return -EINVAL;
            ^
 util/libunwind/../../arch/x86/util/unwind-libunwind.c:110:11: note: each undeclared identifier is reported only once for each function it appears in
 mv: cannot stat 'util/libunwind/.x86_32.o.tmp': No such file or directory
 make[4]: *** [util/libunwind/x86_32.o] Error 1
 make[3]: *** [util] Error 2
 make[2]: *** [libperf-in.o] Error 2
 make[1]: *** [sub-make] Error 2
 make: *** [all] Error 2

It happens when libunwind-x86 feature is detected.
Signed-off-by: default avatarWang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20171206015040.114574-1-wangnan0@huawei.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      44df1afd
    • Arnaldo Carvalho de Melo's avatar
      perf test bpf: Hook on epoll_pwait() · e0337f4f
      Arnaldo Carvalho de Melo authored 
      The 'perf test bpf' was hooking a eBPF program on the SyS_epoll_wait()
kernel function, that was what the epoll_wait() glibc function ended up
calling, but since at least glibc 2.26, the one that comes with, for
instance, Fedora 27, glibc ends up calling SyS_epoll_pwait() when
epoll_wait() is used, causing this 'perf test' entry to fail.

So switch to using epoll_pwait() and hook the eBPF program to the
SyS_epoll_pwait() kernel function to make it work on a wider range of
glibc and kernel versions.
Tested-by: default avatarWang Nan <wangnan0@huawei.com>
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>
Link: https://lkml.kernel.org/n/tip-zynvquy63er8s5mrgsz65pto@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      e0337f4f
    • Arnaldo Carvalho de Melo's avatar
      perf test bpf: Use designated struct field initializers · 13cb2d0f
      Arnaldo Carvalho de Melo authored 
      To follow standard practice in the kernel sources, documenting the
initialization better and helping quickly finding the value for some
field in a struct with many entries.

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: https://lkml.kernel.org/n/tip-syn3hz9hz7ukxlxbx5x6hv20@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      13cb2d0f
    • Arnaldo Carvalho de Melo's avatar
      perf test bpf: Improve message about expected samples · 6703c977
      Arnaldo Carvalho de Melo authored 
      When failing on one of the BPF tests we were just stating:

  BPF filter result incorrect

Add some more info to help figuring out the problem:

 BPF filter result incorrect, expected 56, got 0 samples

This came out while investigating this failure, first seen after
updating the kernel to the 4.15.0-rc6 tag:

  [root@jouet ~]# perf test bpf
  39: BPF filter               :
  39.1: Basic BPF filtering    : FAILED!
  39.2: BPF pinning            : Skip
  39.3: BPF prologue generation: Skip
  39.4: BPF relocation checker : Skip
  [root@jouet ~]#

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: https://lkml.kernel.org/n/tip-403npu7daupv6b2bmxliv5pk@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      6703c977
  3. 06 Jan, 2018 3 commits
    • Ingo Molnar's avatar
      perf/x86/msr: Clean up the code · 9128d3ed
      Ingo Molnar authored 
      Recent changes made a bit of an inconsistent mess out of arch/x86/events/msr.c,
fix it:

 - re-align the initialization tables to be vertically aligned and readable again

 - harmonize comment style in terms of punctuation, capitalization and spelling

 - use curly braces for multi-condition branches

 - remove extra newlines

 - simplify the code a bit

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: kan.liang@intel.com
Link: http://lkml.kernel.org/r/1515169132-3980-1-git-send-email-eranian@google.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      9128d3ed
    • Stephane Eranian's avatar
      perf/x86/msr: Add support for MSR_IA32_THERM_STATUS · 9ae21dd6
      Stephane Eranian authored 
      This patch adds support for the Digital Readout provided by the
IA32_THERM_STATUS MSR (0x19C) on Intel X86 processors. The readout
shows the number of degrees Celcius to the TCC (critical temperature)
supported by the processor. Thus, the larger, the better.

The perf_event support is provided via the msr PMU. The new
logical event is called cpu_thermal_margin. It comes with a unit and
snapshot files. The event shows the current temprature distance (margin).
It is not an accumulating event. The unit is degrees C. The event
is provided per logical CPU to make things simpler but it is the
same for both hyper-threads sharing a physical core.

$ perf stat -I 1000 -a -A -e msr/cpu_thermal_margin/

This will print the temperature for all logical CPUs.
             time CPU                counts unit events
     1.000123741 CPU0                    38 C    msr/cpu_thermal_margin/
     1.000161837 CPU1                    37 C    msr/cpu_thermal_margin/
     1.000187906 CPU2                    36 C    msr/cpu_thermal_margin/
     1.000189046 CPU3                    39 C    msr/cpu_thermal_margin/
     1.000283044 CPU4                    40 C    msr/cpu_thermal_margin/
     1.000344297 CPU5                    40 C    msr/cpu_thermal_margin/
     1.000365832 CPU6                    39 C    msr/cpu_thermal_margin/
     ...

In case the temperature margin cannot be read, the reported value would be -1.

Works on all processors supporting the Digital Readout (dtherm in cpuinfo)
Signed-off-by: default avatarStephane Eranian <eranian@google.com>
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: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: kan.liang@intel.com
Link: http://lkml.kernel.org/r/1515169132-3980-1-git-send-email-eranian@google.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      9ae21dd6
    • Ingo Molnar's avatar
      Merge branch 'linus' into perf/core, to pick up fixes · b6815f35
      Ingo Molnar authored 
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      b6815f35
  5. 05 Jan, 2018 22 commits
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