Skip to content

cloud-kernel
cloud-kernel

openanolis / cloud-kernel
1 年多 前同步成功

通知 160
Star 36
Fork 7
cloud-kernel
cloud-kernel
切换分支/标签
  1. 24 8月, 2016 14 次提交
  3. 19 8月, 2016 2 次提交
    • A
      perf evsel: Do not access outside hw cache name arrays · c53412ee
      由 Arnaldo Carvalho de Melo 提交于 
      We have to check if the values are >= *_MAX, not just >, fix it.

From the bugzilla report:

''In file /tools/perf/util/evsel.c  function __perf_evsel__hw_cache_name
it appears that there is a bug that reads beyond the end of the buffer.
The statement "if (type > PERF_COUNT_HW_CACHE_MAX)" allows type to be
equal to the maximum value. Later, when statement "if
(!perf_evsel__is_cache_op_valid(type, op))" is executed, the function
can access array perf_evsel__hw_cache_stat[type] beyond the end of the
buffer.

It appears to me that the statement "if (type > PERF_COUNT_HW_CACHE_MAX)"
should be "if (type >= PERF_COUNT_HW_CACHE_MAX)"

Bug found with Coverity and manual code review. No attempts were made to
execute the code with a maximum type value.''

Committer note:

Testing it:

  $ perf record -e $(echo $(perf list cache | cut -d \[ -f1) | sed 's/ /,/g') usleep 1
  [ perf record: Woken up 16 times to write data ]
  [ perf record: Captured and wrote 0.023 MB perf.data (34 samples) ]
  $ perf evlist
  L1-dcache-load-misses
  L1-dcache-loads
  L1-dcache-stores
  L1-icache-load-misses
  LLC-load-misses
  LLC-loads
  LLC-store-misses
  LLC-stores
  branch-load-misses
  branch-loads
  dTLB-load-misses
  dTLB-loads
  dTLB-store-misses
  dTLB-stores
  iTLB-load-misses
  iTLB-loads
  node-load-misses
  node-loads
  node-store-misses
  node-stores
  $ perf list cache

  List of pre-defined events (to be used in -e):

    L1-dcache-load-misses        [Hardware cache event]
    L1-dcache-loads              [Hardware cache event]
    L1-dcache-stores             [Hardware cache event]
    L1-icache-load-misses        [Hardware cache event]
    LLC-load-misses              [Hardware cache event]
    LLC-loads                    [Hardware cache event]
    LLC-store-misses             [Hardware cache event]
    LLC-stores                   [Hardware cache event]
    branch-load-misses           [Hardware cache event]
    branch-loads                 [Hardware cache event]
    dTLB-load-misses             [Hardware cache event]
    dTLB-loads                   [Hardware cache event]
    dTLB-store-misses            [Hardware cache event]
    dTLB-stores                  [Hardware cache event]
    iTLB-load-misses             [Hardware cache event]
    iTLB-loads                   [Hardware cache event]
    node-load-misses             [Hardware cache event]
    node-loads                   [Hardware cache event]
    node-store-misses            [Hardware cache event]
    node-stores                  [Hardware cache event]
  $
Reported-by: NBrian Sweeney <bsweeney@lgsinnovations.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=153351Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      c53412ee
    • V
      tools lib: Reinstate strlcpy() header guard with __UCLIBC__ · 0215d59b
      由 Vineet Gupta 提交于 
      perf tools build in recent kernels spews splat when cross compiling with uClibc:

|   CC       util/alias.o
| In file included from tools/perf/util/../ui/../util/cache.h:8:0,
|                 from tools/perf/util/../ui/helpline.h:7,
|                 from tools/perf/util/debug.h:8,
|                 from arch/../util/cpumap.h:9,
|                 from arch/../util/env.h:5,
|                 from arch/common.h:4,
|                 from arch/common.c:3:
| tools/include/linux/string.h:12:15: warning: redundant redeclaration of ‘strlcpy’ [-Wredundant-decls]
|  extern size_t strlcpy(char *dest, const char *src, size_t size);
               ^
This is after commit 61a6445e ("tools lib: Guard the strlcpy() header with
__GLIBC__").

The problem is uClibc also defines __GLIBC__ for exported headers for
applications. So add that specific check to not trip for uClibc.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petri Gynther <pgynther@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: linux-snps-arc@lists.infradead.org
Link: http://lkml.kernel.org/r/1471537703-16439-1-git-send-email-vgupta@synopsys.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      0215d59b
  5. 17 8月, 2016 1 次提交
    • M
      perf unwind: Use addr_location::addr instead of ip for entries · 67540759
      由 Milian Wolff 提交于 
      This fixes the srcline translation for call chains of user space
applications.

Before we got:

    perf report --stdio --no-children -s sym,srcline -g address
     8.92%  [.] main                                 mandelbrot.h:41
            |
            |--3.70%--main +8390240
            |          __libc_start_main +139950056726769
            |          _start +8388650
            |
            |--2.74%--main +8390189
            |
             --2.08%--main +8390296
                       __libc_start_main +139950056726769
                       _start +8388650

     7.59%  [.] main                                 complex:1326
            |
            |--4.79%--main +8390203
            |          __libc_start_main +139950056726769
            |          _start +8388650
            |
             --2.80%--main +8390219

     7.12%  [.] __muldc3                             libgcc2.c:1945
            |
            |--3.76%--__muldc3 +139950060519490
            |          main +8390224
            |          __libc_start_main +139950056726769
            |          _start +8388650
            |
             --3.32%--__muldc3 +139950060519512
                       main +8390224

With this patch applied, we instead get:

    perf report --stdio --no-children -s sym,srcline -g address
     8.92%  [.] main                                 mandelbrot.h:41
            |
            |--3.70%--main mandelbrot.h:41
            |          __libc_start_main +241
            |          _start +4194346
            |
            |--2.74%--main mandelbrot.h:41
            |
             --2.08%--main mandelbrot.h:41
                       __libc_start_main +241
                       _start +4194346

     7.59%  [.] main                                 complex:1326
            |
            |--4.79%--main complex:1326
            |          __libc_start_main +241
            |          _start +4194346
            |
             --2.80%--main complex:1326

     7.12%  [.] __muldc3                             libgcc2.c:1945
            |
            |--3.76%--__muldc3 libgcc2.c:1945
            |          main mandelbrot.h:39
            |          __libc_start_main +241
            |          _start +4194346
            |
             --3.32%--__muldc3 libgcc2.c:1945
                       main mandelbrot.h:39
Suggested-and-Acked-by: NNamhyung Kim <namhyung@kernel.org>
Signed-off-by: NMilian Wolff <milian.wolff@kdab.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
LPU-Reference: 20160816153926.11288-1-milian.wolff@kdab.com
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      67540759
  7. 16 8月, 2016 8 次提交
  9. 13 8月, 2016 3 次提交
  11. 11 8月, 2016 1 次提交
    • D
      tools/testing/nvdimm: fix SIGTERM vs hotplug crash · d8d378fa
      由 Dan Williams 提交于 
      The unit tests crash when hotplug races the previous probe. This race
requires that the loading of the nfit_test module be terminated with
SIGTERM, and the module to be unloaded while the ars scan is still
running.

In contrast to the normal nfit driver, the unit test calls
acpi_nfit_init() twice to simulate hotplug, whereas the nominal case
goes through the acpi_nfit_notify() event handler.  The
acpi_nfit_notify() path is careful to flush the previous region
registration before servicing the hotplug event. The unit test was
missing this guarantee.

 BUG: unable to handle kernel NULL pointer dereference at           (null)
 IP: [<ffffffff810cdce7>] pwq_activate_delayed_work+0x47/0x170
 [..]
 Call Trace:
  [<ffffffff810ce186>] pwq_dec_nr_in_flight+0x66/0xa0
  [<ffffffff810ce490>] process_one_work+0x2d0/0x680
  [<ffffffff810ce331>] ? process_one_work+0x171/0x680
  [<ffffffff810ce88e>] worker_thread+0x4e/0x480
  [<ffffffff810ce840>] ? process_one_work+0x680/0x680
  [<ffffffff810ce840>] ? process_one_work+0x680/0x680
  [<ffffffff810d5343>] kthread+0xf3/0x110
  [<ffffffff8199846f>] ret_from_fork+0x1f/0x40
  [<ffffffff810d5250>] ? kthread_create_on_node+0x230/0x230

Cc: <stable@vger.kernel.org>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
      d8d378fa
  13. 10 8月, 2016 1 次提交
  15. 09 8月, 2016 10 次提交
    • R
      perf probe ppc64le: Fix probe location when using DWARF · 99e608b5
      由 Ravi Bangoria 提交于 
      Powerpc has Global Entry Point and Local Entry Point for functions.  LEP
catches call from both the GEP and the LEP. Symbol table of ELF contains
GEP and Offset from which we can calculate LEP, but debuginfo does not
have LEP info.

Currently, perf prioritize symbol table over dwarf to probe on LEP for
ppc64le. But when user tries to probe with function parameter, we fall
back to using dwarf(i.e. GEP) and when function called via LEP, probe
will never hit.

For example:

  $ objdump -d vmlinux
    ...
    do_sys_open():
    c0000000002eb4a0:       e8 00 4c 3c     addis   r2,r12,232
    c0000000002eb4a4:       60 00 42 38     addi    r2,r2,96
    c0000000002eb4a8:       a6 02 08 7c     mflr    r0
    c0000000002eb4ac:       d0 ff 41 fb     std     r26,-48(r1)

  $ sudo ./perf probe do_sys_open
  $ sudo cat /sys/kernel/debug/tracing/kprobe_events
    p:probe/do_sys_open _text+3060904

  $ sudo ./perf probe 'do_sys_open filename:string'
  $ sudo cat /sys/kernel/debug/tracing/kprobe_events
    p:probe/do_sys_open _text+3060896 filename_string=+0(%gpr4):string

For second case, perf probed on GEP. So when function will be called via
LEP, probe won't hit.

  $ sudo ./perf record -a -e probe:do_sys_open ls
    [ perf record: Woken up 1 times to write data ]
    [ perf record: Captured and wrote 0.195 MB perf.data ]

To resolve this issue, let's not prioritize symbol table, let perf
decide what it wants to use. Perf is already converting GEP to LEP when
it uses symbol table. When perf uses debuginfo, let it find LEP offset
form symbol table. This way we fall back to probe on LEP for all cases.

After patch:

  $ sudo ./perf probe 'do_sys_open filename:string'
  $ sudo cat /sys/kernel/debug/tracing/kprobe_events
    p:probe/do_sys_open _text+3060904 filename_string=+0(%gpr4):string

  $ sudo ./perf record -a -e probe:do_sys_open ls
    [ perf record: Woken up 1 times to write data ]
    [ perf record: Captured and wrote 0.197 MB perf.data (11 samples) ]
Signed-off-by: NRavi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: NMasami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Balbir Singh <bsingharora@gmail.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: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1470723805-5081-2-git-send-email-ravi.bangoria@linux.vnet.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      99e608b5
    • R
      perf probe: Add function to post process kernel trace events · d820456d
      由 Ravi Bangoria 提交于 
      Instead of inline code, introduce function to post process kernel
probe trace events.
Signed-off-by: NRavi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: NMasami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Balbir Singh <bsingharora@gmail.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: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1470723805-5081-1-git-send-email-ravi.bangoria@linux.vnet.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      d820456d
    • A
      tools: Sync cpufeatures headers with the kernel · 840b49ba
      由 Arnaldo Carvalho de Melo 提交于 
      Due to:

  1e61f78b ("x86/cpufeature: Make sure DISABLED/REQUIRED macros are updated")

No changes to tools using those headers (tools/arch/x86/lib/mem{set,cpu}_64.S)
seems necessary.

Detected by the tools build header drift checker:

  $ make -C tools/perf O=/tmp/build/perf
  make: Entering directory '/home/acme/git/linux/tools/perf'
    BUILD:   Doing 'make -j4' parallel build
    GEN      /tmp/build/perf/common-cmds.h
  Warning: tools/arch/x86/include/asm/disabled-features.h differs from kernel
  Warning: tools/arch/x86/include/asm/required-features.h differs from kernel
  Warning: tools/arch/x86/include/asm/cpufeatures.h differs from kernel
    CC       /tmp/build/perf/util/probe-finder.o
    CC       /tmp/build/perf/builtin-help.o
  <SNIP>
  ^C$

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Dave Hansen <dave.hansen@linux.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-ja75m7zk8j0jkzmrv16i5ehw@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      840b49ba
    • A
      toops: Sync tools/include/uapi/linux/bpf.h with the kernel · 791cceb8
      由 Arnaldo Carvalho de Melo 提交于 
      The way we're using kernel headers in tools/ now, with a copy that is
made to the same path prefixed by "tools/" plus checking if that copy
got stale, i.e. if the kernel counterpart changed, helps in keeping
track with new features that may be useful for tools to exploit.

For instance, looking at all the changes to bpf.h since it was last
copied to tools/include brings this to toolers' attention:

Need to investigate this one to check how to run a program via perf, setting up
a BPF event, that will take advantage of the way perf already calls clang/LLVM,
sets up the event and runs the workload in a single command line, helping in
debugging such semi cooperative programs:

  96ae5227 ("bpf: Add bpf_probe_write_user BPF helper to be called in tracers")

This one needs further investigation about using the feature it improves
in 'perf trace' to do some tcpdumpin' mixed with syscalls, tracepoints,
probe points, callgraphs, etc:

  555c8a86 ("bpf: avoid stack copy and use skb ctx for event output")

Add tracing just packets that are related to some container to that mix:

  4a482f34 ("cgroup: bpf: Add bpf_skb_in_cgroup_proto")
  4ed8ec52 ("cgroup: bpf: Add BPF_MAP_TYPE_CGROUP_ARRAY")

Definetely needs to have example programs accessing task_struct from a bpf proggie
started from 'perf trace':

  606274c5 ("bpf: introduce bpf_get_current_task() helper")

Core networking related, XDP:

  6ce96ca3 ("bpf: add XDP_TX xdp_action for direct forwarding")
  6a773a15 ("bpf: add XDP prog type for early driver filter")
  13c5c240 ("bpf: add bpf_get_hash_recalc helper")
  d2485c42 ("bpf: add bpf_skb_change_type helper")
  6578171a ("bpf: add bpf_skb_change_proto helper")

Changes detected by the tools build system:

  $ make -C tools/perf O=/tmp/build/perf install-bin
  make: Entering directory '/home/acme/git/linux/tools/perf'
    BUILD:   Doing 'make -j4' parallel build
  Warning: tools/include/uapi/linux/bpf.h differs from kernel
    INSTALL  GTK UI
    CC       /tmp/build/perf/bench/mem-memcpy-x86-64-asm.o
  <SNIP>
  $

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Brenden Blanco <bblanco@plumgrid.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Sargun Dhillon <sargun@sargun.me>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-difq4ts1xvww6eyfs9e7zlft@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      791cceb8
    • A
      tools: Sync cpufeatures.h and vmx.h with the kernel · bebfb730
      由 Arnaldo Carvalho de Melo 提交于 
      There were changes related to the deprecation of the "pcommit"
instruction:

  fd1d961d ("x86/insn: remove pcommit")
  dfa169bb ("Revert "KVM: x86: add pcommit support"")

No need to update anything in the tools, as "pcommit" wasn't being
listed on the VMX_EXIT_REASONS in the tools/perf/arch/x86/util/kvm-stat.c
file.

Just grab fresh copies of these files to silence the file cache
coherency detector:

  $ make -C tools/perf O=/tmp/build/perf install-bin
  make: Entering directory '/home/acme/git/linux/tools/perf'
    BUILD:   Doing 'make -j4' parallel build
  Warning: tools/arch/x86/include/asm/cpufeatures.h differs from kernel
  Warning: tools/arch/x86/include/uapi/asm/vmx.h differs from kernel
    INSTALL  GTK UI
  <SNIP>
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Link: http://lkml.kernel.org/n/tip-07pmcc1ysydhyyxbmp1vt0l4@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      bebfb730
    • N
      perf probe: Support signedness casting · 19f00b01
      由 Naohiro Aota 提交于 
      The 'perf probe' tool detects a variable's type and use the detected
type to add a new probe. Then, kprobes prints its variable in
hexadecimal format if the variable is unsigned and prints in decimal if
it is signed.

We sometimes want to see unsigned variable in decimal format (i.e.
sector_t or size_t). In that case, we need to investigate the variable's
size manually to specify just signedness.

This patch add signedness casting support. By specifying "s" or "u" as a
type, perf-probe will investigate variable size as usual and use the
specified signedness.

E.g. without this:

  $ perf probe -a 'submit_bio bio->bi_iter.bi_sector'
  Added new event:
    probe:submit_bio     (on submit_bio with bi_sector=bio->bi_iter.bi_sector)
  You can now use it in all perf tools, such as:
          perf record -e probe:submit_bio -aR sleep 1
  $ cat trace_pipe|head
          dbench-9692  [003] d..1   971.096633: submit_bio: (submit_bio+0x0/0x140) bi_sector=0x3a3d00
          dbench-9692  [003] d..1   971.096685: submit_bio: (submit_bio+0x0/0x140) bi_sector=0x1a3d80
          dbench-9692  [003] d..1   971.096687: submit_bio: (submit_bio+0x0/0x140) bi_sector=0x3a3d80
...
  // need to investigate the variable size
  $ perf probe -a 'submit_bio bio->bi_iter.bi_sector:s64'
  Added new event:
    probe:submit_bio     (on submit_bio with bi_sector=bio->bi_iter.bi_sector:s64)
  You can now use it in all perf tools, such as:
        perf record -e probe:submit_bio -aR sleep 1

  With this:

  // just use "s" to cast its signedness
  $ perf probe -v -a 'submit_bio bio->bi_iter.bi_sector:s'
  Added new event:
    probe:submit_bio     (on submit_bio with bi_sector=bio->bi_iter.bi_sector:s)
  You can now use it in all perf tools, such as:
          perf record -e probe:submit_bio -aR sleep 1
  $ cat trace_pipe|head
          dbench-9689  [001] d..1  1212.391237: submit_bio: (submit_bio+0x0/0x140) bi_sector=128
          dbench-9689  [001] d..1  1212.391252: submit_bio: (submit_bio+0x0/0x140) bi_sector=131072
          dbench-9697  [006] d..1  1212.398611: submit_bio: (submit_bio+0x0/0x140) bi_sector=30208

  This commit also update perf-probe.txt to describe "types". Most parts
  are based on existing documentation: Documentation/trace/kprobetrace.txt

Committer note:

Testing using 'perf trace':

  # perf probe -a 'submit_bio bio->bi_iter.bi_sector'
  Added new event:
    probe:submit_bio     (on submit_bio with bi_sector=bio->bi_iter.bi_sector)

  You can now use it in all perf tools, such as:

	perf record -e probe:submit_bio -aR sleep 1

  # trace --no-syscalls --ev probe:submit_bio
      0.000 probe:submit_bio:(ffffffffac3aee00) bi_sector=0xc133c0)
   3181.861 probe:submit_bio:(ffffffffac3aee00) bi_sector=0x6cffb8)
   3181.881 probe:submit_bio:(ffffffffac3aee00) bi_sector=0x6cffc0)
   3184.488 probe:submit_bio:(ffffffffac3aee00) bi_sector=0x6cffc8)
<SNIP>
   4717.927 probe:submit_bio:(ffffffffac3aee00) bi_sector=0x4dc7a88)
   4717.970 probe:submit_bio:(ffffffffac3aee00) bi_sector=0x4dc7880)
  ^C[root@jouet ~]#

Now, using this new feature:

[root@jouet ~]# perf probe -a 'submit_bio bio->bi_iter.bi_sector:s'
Added new event:
  probe:submit_bio     (on submit_bio with bi_sector=bio->bi_iter.bi_sector:s)

You can now use it in all perf tools, such as:

	perf record -e probe:submit_bio -aR sleep 1

  [root@jouet ~]# trace --no-syscalls --ev probe:submit_bio
     0.000 probe:submit_bio:(ffffffffac3aee00) bi_sector=7145704)
     0.017 probe:submit_bio:(ffffffffac3aee00) bi_sector=7145712)
     0.019 probe:submit_bio:(ffffffffac3aee00) bi_sector=7145720)
     2.567 probe:submit_bio:(ffffffffac3aee00) bi_sector=7145728)
  5631.919 probe:submit_bio:(ffffffffac3aee00) bi_sector=0)
  5631.941 probe:submit_bio:(ffffffffac3aee00) bi_sector=8)
  5631.945 probe:submit_bio:(ffffffffac3aee00) bi_sector=16)
  5631.948 probe:submit_bio:(ffffffffac3aee00) bi_sector=24)
  ^C#

With callchains:

  # trace --no-syscalls --ev probe:submit_bio/max-stack=10/
     0.000 probe:submit_bio:(ffffffffac3aee00) bi_sector=50662544)
                                       submit_bio+0xa8200001 ([kernel.kallsyms])
                                       submit_bh+0xa8200013 ([kernel.kallsyms])
                                       jbd2_journal_commit_transaction+0xa8200691 ([kernel.kallsyms])
                                       kjournald2+0xa82000ca ([kernel.kallsyms])
                                       kthread+0xa82000d8 ([kernel.kallsyms])
                                       ret_from_fork+0xa820001f ([kernel.kallsyms])
     0.023 probe:submit_bio:(ffffffffac3aee00) bi_sector=50662552)
                                       submit_bio+0xa8200001 ([kernel.kallsyms])
                                       submit_bh+0xa8200013 ([kernel.kallsyms])
                                       jbd2_journal_commit_transaction+0xa8200691 ([kernel.kallsyms])
                                       kjournald2+0xa82000ca ([kernel.kallsyms])
                                       kthread+0xa82000d8 ([kernel.kallsyms])
                                       ret_from_fork+0xa820001f ([kernel.kallsyms])
     0.027 probe:submit_bio:(ffffffffac3aee00) bi_sector=50662560)
                                       submit_bio+0xa8200001 ([kernel.kallsyms])
                                       submit_bh+0xa8200013 ([kernel.kallsyms])
                                       jbd2_journal_commit_transaction+0xa8200691 ([kernel.kallsyms])
                                       kjournald2+0xa82000ca ([kernel.kallsyms])
                                       kthread+0xa82000d8 ([kernel.kallsyms])
                                       ret_from_fork+0xa820001f ([kernel.kallsyms])
     2.593 probe:submit_bio:(ffffffffac3aee00) bi_sector=50662568)
                                       submit_bio+0xa8200001 ([kernel.kallsyms])
                                       submit_bh+0xa8200013 ([kernel.kallsyms])
                                       journal_submit_commit_record+0xa82001ac ([kernel.kallsyms])
                                       jbd2_journal_commit_transaction+0xa82012e8 ([kernel.kallsyms])
                                       kjournald2+0xa82000ca ([kernel.kallsyms])
                                       kthread+0xa82000d8 ([kernel.kallsyms])
                                       ret_from_fork+0xa820001f ([kernel.kallsyms])
  ^C#
Signed-off-by: NNaohiro Aota <naohiro.aota@hgst.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1470710408-23515-1-git-send-email-naohiro.aota@hgst.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      19f00b01
    • M
      perf stat: Avoid skew when reading events · 3df33eff
      由 Mark Rutland 提交于 
      When we don't have a tracee (i.e. we're attaching to a task or CPU),
counters can still be running after our workload finishes, and can still
be running as we read their values. As we read events one-by-one, there
can be arbitrary skew between values of events, even within a group.
This means that ratios within an event group are not reliable.

This skew can be seen if measuring a group of identical events, e.g:

  # perf stat -a -C0 -e '{cycles,cycles}' sleep 1

To avoid this, we must stop groups from counting before we read the
values of any constituent events. This patch adds and makes use of a new
disable_counters() helper, which disables group leaders (and thus each
group as a whole). This mirrors the use of enable_counters() for
starting event groups in the absence of a tracee.

Closing a group leader splits the group, and without a disabled group
leader the newly split events will begin counting. Thus to ensure counts
are reliable we must defer closing group leaders until all counts have
been read. To do so this patch removes the event closing logic from the
read_counters() helper, explicitly closes the events using
perf_evlist__close(), which also aids legibility.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1470747869-3567-1-git-send-email-mark.rutland@arm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      3df33eff
    • K
      perf probe: Fix module name matching · cb3f3378
      由 Konstantin Khlebnikov 提交于 
      If module is "module" then dso->short_name is "[module]".  Substring
comparing is't enough: "raid10" matches to "[raid1]".  This patch also
checks terminating zero in module name.
Signed-off-by: NKonstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: NMasami Hiramatsu <mhiramat@kernel.org>
Link: http://lkml.kernel.org/r/147039975648.715620.12985971832789032159.stgit@buzzSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      cb3f3378
    • M
      perf probe: Adjust map->reloc offset when finding kernel symbol from map · 8e34189b
      由 Masami Hiramatsu 提交于 
      Adjust map->reloc offset for the unmapped address when finding
alternative symbol address from map, because KASLR can relocate the
kernel symbol address.

The same adjustment has been done when finding appropriate kernel symbol
address from map which was introduced by commit f90acac7 ("perf
probe: Find given address from offline dwarf")
Reported-by: NArnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: NMasami Hiramatsu <masami.hiramatsu@linaro.org>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20160806192948.e366f3fbc4b194de600f8326@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      8e34189b
    • A
      perf hists: Trim libtraceevent trace_seq buffers · 887fa86d
      由 Arnaldo Carvalho de Melo 提交于 
      When we use libtraceevent to format trace event fields into printable
strings to use in hist entries it is important to trim it from the
default 4 KiB it starts with to what is really used, to reduce the
memory footprint, so use realloc(seq.buffer, seq.len + 1) when returning
the seq.buffer formatted with the fields contents.
Reported-and-Tested-by: NWang 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: http://lkml.kernel.org/n/tip-t3hl7uxmilrkigzmc90rlhk2@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      887fa86d