1. 23 9月, 2016 3 次提交
  2. 22 9月, 2016 4 次提交
  3. 21 9月, 2016 5 次提交
  4. 20 9月, 2016 4 次提交
    • A
      perf annotate: Resolve 'call' operands to function names · 5f62d4fd
      Arnaldo Carvalho de Melo 提交于
      Before this patch the '_raw_spin_lock_irqsave' and 'update_rq_clock' operands
      were appearing just as hexadecimal numbers:
      
        update_blocked_averages  /proc/kcore
             │       push   %r12
             │       push   %rbx
             │       and    $0xfffffffffffffff0,%rsp
             │       sub    $0x40,%rsp
             │       add    -0x662cac00(,%rdi,8),%rax
             │       mov    %rax,%rbx
             │       mov    %rax,%rdi
             │       mov    %rax,0x38(%rsp)
             │     → callq  _raw_spin_lock_irqsave
             │       mov    %rbx,%rdi
             │       mov    %rax,0x30(%rsp)
             │     → callq  update_rq_clock
             │       mov    0x8d0(%rbx),%rax
             │       lea    0x8d0(%rbx),%r11
      
      To check that all is right one can always use the 'o' hotkey and see
      the original objdump -dS output, that for this case is:
      
        update_blocked_averages  /proc/kcore
             │ffffffff990d5489:   push   %r12
             │ffffffff990d548b:   push   %rbx
             │ffffffff990d548c:   and    $0xfffffffffffffff0,%rsp
             │ffffffff990d5490:   sub    $0x40,%rsp
             │ffffffff990d5494:   add    -0x662cac00(,%rdi,8),%rax
             │ffffffff990d549c:   mov    %rax,%rbx
             │ffffffff990d549f:   mov    %rax,%rdi
             │ffffffff990d54a2:   mov    %rax,0x38(%rsp)
             │ffffffff990d54a7: → callq  0xffffffff997eb7a0
             │ffffffff990d54ac:   mov    %rbx,%rdi
             │ffffffff990d54af:   mov    %rax,0x30(%rsp)
             │ffffffff990d54b4: → callq  0xffffffff990c7720
             │ffffffff990d54b9:   mov    0x8d0(%rbx),%rax
             │ffffffff990d54c0:   lea    0x8d0(%rbx),%r11
      
      Use the 'h' hotkey to see a list of available hotkeys.
      
      More work needed to cover operands for other instructions, such as 'mov',
      that can resolve variable names, etc.
      
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Chris Riyder <chris.ryder@arm.com>
      Cc: David Ahern <dsahern@gmail.com>
      Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
      Cc: Masami Hiramatsu <mhiramat@kernel.org>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
      Cc: Pawel Moll <pawel.moll@arm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
      Cc: Russell King <rmk+kernel@arm.linux.org.uk>
      Cc: Taeung Song <treeze.taeung@gmail.com>
      Cc: Wang Nan <wangnan0@huawei.com>
      Link: http://lkml.kernel.org/n/tip-xqgtw9mzmzcjgwkis9kiiv1p@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      5f62d4fd
    • A
      perf annotate: Pass the symbol's map/dso to the instruction parsers · bff5c306
      Arnaldo Carvalho de Melo 提交于
      So that things like:
      
             → callq  0xffffffff993e3230
      
      found while disassembling /proc/kcore can be beautified by later
      patches, that will resolve that address to a function, looking it up in
      /proc/kallsyms.
      
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Chris Riyder <chris.ryder@arm.com>
      Cc: David Ahern <dsahern@gmail.com>
      Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
      Cc: Masami Hiramatsu <mhiramat@kernel.org>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
      Cc: Pawel Moll <pawel.moll@arm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
      Cc: Russell King <rmk+kernel@arm.linux.org.uk>
      Cc: Taeung Song <treeze.taeung@gmail.com>
      Cc: Wang Nan <wangnan0@huawei.com>
      Link: http://lkml.kernel.org/n/tip-p76myuke4j7gplg54amaklxk@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      bff5c306
    • R
      perf annotate: Do not ignore call instruction with indirect target · 88a7fcf9
      Ravi Bangoria 提交于
      Do not ignore call instruction with indirect target when its already
      identified as a call. This is an extension of commit e8ea1561 ("perf
      annotate: Use raw form for register indirect call instructions") to
      generalize annotation for all instructions with indirect calls.
      
      This is needed for certain powerpc call instructions that use address in
      a register (such as bctrl, btarl, ...).
      
      Apart from that, when kcore is used to disassemble function, all call
      instructions were ignored. This patch will fix it as a side effect by
      not ignoring them. For example,
      
      Before (with kcore):
             mov    %r13,%rdi
             callq  0xffffffff811a7e70
           ^ jmpq   64
             mov    %gs:0x7ef41a6e(%rip),%al
      
      After (with kcore):
             mov    %r13,%rdi
           > callq  0xffffffff811a7e70
           ^ jmpq   64
             mov    %gs:0x7ef41a6e(%rip),%al
      Suggested-by: NMichael Ellerman <mpe@ellerman.id.au>
      [Suggested about 'bctrl' instruction]
      Signed-off-by: NRavi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Chris Riyder <chris.ryder@arm.com>
      Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
      Cc: Masami Hiramatsu <mhiramat@kernel.org>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
      Cc: Pawel Moll <pawel.moll@arm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Russell King <rmk+kernel@arm.linux.org.uk>
      Cc: Taeung Song <treeze.taeung@gmail.com>
      Link: http://lkml.kernel.org/r/1471611578-11255-5-git-send-email-ravi.bangoria@linux.vnet.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      88a7fcf9
    • J
      perf hists: Fix width computation for srcline sort entry · f666ac0d
      Jiri Olsa 提交于
      Adding header size to width computation for srcline sort entry,
      because it's possible to get empty data with ':0' which set width
      of 2 which is lower than width needed to display column header.
      Signed-off-by: NJiri Olsa <jolsa@kernel.org>
      Cc: Andi Kleen <andi@firstfloor.org>
      Cc: David Ahern <dsahern@gmail.com>
      Cc: Don Zickus <dzickus@redhat.com>
      Cc: Joe Mario <jmario@redhat.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Link: http://lkml.kernel.org/r/1474290610-23241-62-git-send-email-jolsa@kernel.org
      [ Added declaration to sort.h ]
      Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      f666ac0d
  5. 19 9月, 2016 2 次提交
    • W
      tools include: Add mman macros needed by perf for all arch · f82b7746
      Wang Nan 提交于
      Some macros required by tools/perf/trace/beauty/mmap.c is not support
      for all architectures. For example, MAP_32BIT is defined on x86 only,
      alpha doesn't define MADV_HWPOISON and MADV_SOFT_OFFLINE.
      
      This patch regenerates mman.h for each arch, defines these missing
      macros for perf. For missing MADV_*, fall back to asm-generic/mman-common
      because they are in a 'case ...' statement. For flags, define it to 0.
      
      Following is the script to generate this patch:
      
       macros=`cat $0 | awk 'V==1 {print}; /^# start macro list/ {V=1}'`
       rm `find ./tools/arch/ -name mman.h`
       for arch in `ls tools/arch`
       do
         [ -d tools/arch/$arch/include/uapi/asm ] || mkdir -p tools/arch/$arch/include/uapi/asm
         src=arch/$arch/include/uapi/asm/mman.h
         target=tools/arch/$arch/include/uapi/asm/mman.h.tmp
         real_target=tools/arch/$arch/include/uapi/asm/mman.h
         guard="TOOLS_ARCH_"`echo $arch | awk '{print toupper($0)}'`_UAPI_ASM_MMAN_FIX_H
         rm -f $target
      
         [ -f $src ] &&
         for m in $macros
         do
           if grep '#define[ \t]*'$m $src > /dev/null 2>&1
           then
             grep -h '#define[ \t]*'$m $src | sed 's/[ \t]*\/\*.*$//g' >> $target
           fi
         done
      
         if [ -f $src ]
         then
            grep '#include <asm-generic' $src >> $target
         else
            echo "#include <asm-generic/mman.h>" >> $target
         fi
      
         touch $real_target
         for m in $macros
         do
           if cat << EOF | gcc -Itools/arch/$arch/include -Itools/arch/$arch/include/uapi -Iinclude/ -Iinclude/uapi -E - | grep $m > /dev/null 2>&1
       #include <uapi/asm/mman.h.tmp>
       #include <uapi/linux/mman.h>
       $m
       EOF
         then
           echo "Fixing $m for $arch"
           echo "/* $m is undefined on $arch, fix it for perf */" >> $target
           if echo $m | grep '^MADV_' > /dev/null 2>&1
           then
             grep -h '#define[ \t]*'$m include/uapi/asm-generic/mman-common.h | sed 's/[ \t]*\/\*.*$//g' >> $target
           else
             echo "#define $m	0" >> $target
           fi
         fi
         done
      
         real_target=tools/arch/$arch/include/uapi/asm/mman.h
         echo '#ifndef '$guard > $real_target
         echo '#define '$guard >> $real_target
         cat $target | sed 's|asm-generic|uapi/asm-generic|g' >> $real_target
         echo '#endif' >> $real_target
         rm $target
         echo "$real_target"
       done
      
       exit 0
       # Following macros are extracted from:
       # tools/perf/trace/beauty/mmap.c
       #
       # start macro list
       MADV_DODUMP
       MADV_DOFORK
       MADV_DONTDUMP
       MADV_DONTFORK
       MADV_DONTNEED
       MADV_FREE
       MADV_HUGEPAGE
       MADV_HWPOISON
       MADV_MERGEABLE
       MADV_NOHUGEPAGE
       MADV_NORMAL
       MADV_RANDOM
       MADV_REMOVE
       MADV_SEQUENTIAL
       MADV_SOFT_OFFLINE
       MADV_UNMERGEABLE
       MADV_WILLNEED
       MAP_32BIT
       MAP_ANONYMOUS
       MAP_DENYWRITE
       MAP_EXECUTABLE
       MAP_FILE
       MAP_FIXED
       MAP_GROWSDOWN
       MAP_HUGETLB
       MAP_LOCKED
       MAP_NONBLOCK
       MAP_NORESERVE
       MAP_POPULATE
       MAP_PRIVATE
       MAP_SHARED
       MAP_STACK
       MAP_UNINITIALIZED
       MREMAP_FIXED
       MREMAP_MAYMOVE
       PROT_EXEC
       PROT_GROWSDOWN
       PROT_GROWSUP
       PROT_NONE
       PROT_READ
       PROT_SEM
       PROT_WRITE
      Signed-off-by: NWang Nan <wangnan0@huawei.com>
      Tested-by: NKim Phillips <kim.phillips@arm.com>
      Tested-by: NNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
      Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
      Cc: Zefan Li <lizefan@huawei.com>
      Cc: pi3orama@163.com
      Fixes: 277cf08f ("perf trace beauty mmap: Fix defines for non !x86_64")
      Link: http://lkml.kernel.org/r/1473850649-83389-3-git-send-email-wangnan0@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      f82b7746
    • W
      perf trace beauty mmap: Add missing MADV_FREE · f752e90e
      Wang Nan 提交于
      tools/perf/trace/beauty/mmap.c forgets to check MADV_FREE.
      This patch fixes it.
      Signed-off-by: NWang Nan <wangnan0@huawei.com>
      Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
      Cc: Zefan Li <lizefan@huawei.com>
      Cc: pi3orama@163.com
      Link: http://lkml.kernel.org/r/1473850649-83389-2-git-send-email-wangnan0@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      f752e90e
  6. 14 9月, 2016 11 次提交
  7. 12 9月, 2016 2 次提交
    • N
      perf hists browser: Fix event group display · d9ea48bc
      Namhyung Kim 提交于
      Milian reported that the event group on TUI shows duplicated overhead.
      This was due to a bug on calculating hpp->buf position.  The
      hpp_advance() was called from __hpp__slsmg_color_printf() on TUI but
      it's already called from the hpp__call_print_fn macro in __hpp__fmt().
      The end result is that the print function returns number of bytes it
      printed but the buffer advanced twice of the length.
      
      This is generally not a problem since it doesn't need to access the
      buffer again.  But with event group, overhead needs to be printed
      multiple times and hist_entry__snprintf_alignment() tries to fill the
      space with buffer after it printed.  So it (brokenly) showed the last
      overhead again.
      
      The bug was there from the beginning, but I think it's only revealed
      when the alignment function was added.
      Reported-by: NMilian Wolff <milian.wolff@kdab.com>
      Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
      Cc: Andi Kleen <andi@firstfloor.org>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Fixes: 89fee709 ("perf hists: Do column alignment on the format iterator")
      Link: http://lkml.kernel.org/r/20160912061958.16656-2-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      d9ea48bc
    • A
      perf probe: Fix dwarf regs table for x86_64 · 7a023fd2
      Arnaldo Carvalho de Melo 提交于
      In 293d5b43 ("perf probe: Support probing on offline cross-arch binary")
      DWARF register tables were introduced for many architectures, with the one for
      the "dx" register being broken for x86_64, which got noticed by the 'perf test
      bpf' testcase, that has this difference from a successful run to one that
      fails, with the aforementioned patch:
      
        -Writing event: p:perf_bpf_probe/func _text+5197232 f_mode=+68(%di):x32 offset=%si:s64 orig=dx:s32
        -Failed to write event: Invalid argument
        -bpf_probe: failed to apply perf probe eventsFailed to add events selected by BPF
        +Writing event: p:perf_bpf_probe/func _text+5197232 f_mode=+68(%di):x32 offset=%si:s64 orig=%dx:s32
      
      Add the missing '%' to '%dx' to fix this.
      Acked-by: NMasami Hiramatsu <mhiramat@kernel.org>
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: David Ahern <dsahern@gmail.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Wang Nan <wangnan0@huawei.com>
      Fixes: 293d5b43 ("perf probe: Support probing on offline cross-arch binary")
      Link: https://lkml.kernel.org/r/20160909145955.GC32585@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      7a023fd2
  8. 09 9月, 2016 4 次提交
    • R
      perf powerpc: Fix build-test failure · 25b8592e
      Ravi Bangoria 提交于
      'make -C tools/perf build-test' is failing with below log for poewrpc.
      
        In file included from /tmp/tmp.3eEwmGlYaF/perf-4.8.0-rc4/tools/perf/perf.h:15:0,
                         from util/cpumap.h:8,
                         from util/env.c:1:
        /tmp/tmp.3eEwmGlYaF/perf-4.8.0-rc4/tools/perf/perf-sys.h:23:56:
        fatal error: ../../arch/powerpc/include/uapi/asm/unistd.h: No such file or directory
        compilation terminated.
      
      I bisected it and found it's failing from commit ad430729 ("Remove:
      kernel unistd*h files from perf's MANIFEST, not used").
      
      Header file '../../arch/powerpc/include/uapi/asm/unistd.h' is included
      only for powerpc in tools/perf/perf-sys.h.
      
      By looking closly at commit history, I found little weird thing:
      
      Commit f2d9cae9 ("perf powerpc: Use uapi/unistd.h to fix build
      error") replaced 'asm/unistd.h' with 'uapi/asm/unistd.h'
      
      Commit d2709c7c ("perf: Make perf build for x86 with UAPI
      disintegration applied") removes all arch specific 'uapi/asm/unistd.h'
      for all archs and adds generic <asm/unistd.h>.
      
      Commit f0b9abfb ("Merge branch 'linus' into perf/core") again
      includes 'uapi/asm/unistd.h' for powerpc. Don't know how exactly this
      happened as this change is not part of commit also.
      Signed-off-by: NRavi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Link: http://lkml.kernel.org/r/1472630591-5089-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com
      Fixes: ad430729 ("Remove: kernel unistd*h files from perf's MANIFEST, not used")
      Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      25b8592e
    • M
      perf pmu: Support alternative sysfs cpumask · 7e3fcffe
      Mark Rutland 提交于
      The perf tools can read a cpumask file for a PMU, describing a subset of
      CPUs which that PMU covers. So far this has only been used to cater for
      uncore PMUs, which in practice happen to only have a single CPU
      described in the mask.
      
      Until recently, the perf tools only correctly handled cpumask containing
      a single CPU, and only when monitoring in system-wide mode. For example,
      prior to commit 00e727bb ("perf stat: Balance opening and
      reading events"), a mask with more than a single CPU could cause perf
      stat to hang. When a CPU PMU covers a subset of CPUs, but lacks a
      cpumask, perf record will fail to open events (on the cores the PMU does
      not support), and gives up.
      
      For systems with heterogeneous CPUs such as ARM big.LITTLE systems, this
      presents a problem. We have a PMU for each microarchitecture (e.g. a big
      PMU and a little PMU), and would like to expose a cpumask for each (so
      as to allow perf record and other tools to do the right thing). However,
      doing so kernel-side will cause old perf binaries to not function (e.g.
      hitting the issue solved by 00e727bb), and thus commits the
      cardinal sin of breaking (existing) userspace.
      
      To address this chicken-and-egg problem, this patch adds support got a
      new file, cpus, which is largely identical to the existing cpumask file.
      A kernel can expose this file, knowing that new perf binaries will
      correctly support it, while old perf binaries will not look for it (and
      thus will not be broken).
      Signed-off-by: NMark Rutland <mark.rutland@arm.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Will Deacon <will.deacon@arm.com>
      Link: http://lkml.kernel.org/r/1473330112-28528-8-git-send-email-mark.rutland@arm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      7e3fcffe
    • M
      perf evlist: Only open events on CPUs an evsel permits · 9f21b815
      Mark Rutland 提交于
      In systems with heterogeneous CPU PMUs, it's possible for each evsel to
      cover a distinct set of CPUs, and hence the cpu_map associated with each
      evsel may have a distinct idx<->id mapping. Any of these may be distinct
      from the evlist's cpu map.
      
      Events can be tied to the same fd so long as they use the same per-cpu
      ringbuffer (i.e. so long as they are on the same CPU). To acquire the
      correct FDs, we must compare the Linux logical IDs rather than the evsel
      or evlist indices.
      
      This path adds logic to perf_evlist__mmap_per_evsel to handle this,
      translating IDs as required. As PMUs may cover a subset of CPUs from the
      evlist, we skip the CPUs a PMU cannot handle.
      
      Without this patch, perf record may try to mmap erroneous FDs on
      heterogeneous systems, and will bail out early rather than running the
      workload.
      Signed-off-by: NMark Rutland <mark.rutland@arm.com>
      Acked-by: NJiri Olsa <jolsa@kernel.org>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Will Deacon <will.deacon@arm.com>
      Link: http://lkml.kernel.org/r/1473330112-28528-7-git-send-email-mark.rutland@arm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      9f21b815
    • P
      perf annotate: Add branch stack / basic block · 70fbe057
      Peter Zijlstra 提交于
      I wanted to know the hottest path through a function and figured the
      branch-stack (LBR) information should be able to help out with that.
      
      The below uses the branch-stack to create basic blocks and generate
      statistics from them.
      
              from    to              branch_i
              * ----> *
                      |
                      | block
                      v
                      * ----> *
                      from    to      branch_i+1
      
      The blocks are broken down into non-overlapping ranges, while tracking
      if the start of each range is an entry point and/or the end of a range
      is a branch.
      
      Each block iterates all ranges it covers (while splitting where required
      to exactly match the block) and increments the 'coverage' count.
      
      For the range including the branch we increment the taken counter, as
      well as the pred counter if flags.predicted.
      
      Using these number we can find if an instruction:
      
       - had coverage; given by:
      
              br->coverage / br->sym->max_coverage
      
         This metric ensures each symbol has a 100% spot, which reflects the
         observation that each symbol must have a most covered/hottest
         block.
      
       - is a branch target: br->is_target && br->start == add
      
       - for targets, how much of a branch's coverages comes from it:
      
      	target->entry / branch->coverage
      
       - is a branch: br->is_branch && br->end == addr
      
       - for branches, how often it was taken:
      
              br->taken / br->coverage
      
         after all, all execution that didn't take the branch would have
         incremented the coverage and continued onward to a later branch.
      
       - for branches, how often it was predicted:
      
              br->pred / br->taken
      
      The coverage percentage is used to color the address and asm sections;
      for low (<1%) coverage we use NORMAL (uncolored), indicating that these
      instructions are not 'important'. For high coverage (>75%) we color the
      address RED.
      
      For each branch, we add an asm comment after the instruction with
      information on how often it was taken and predicted.
      
      Output looks like (sans color, which does loose a lot of the
      information :/)
      
      $ perf record --branch-filter u,any -e cycles:p ./branches 27
      $ perf annotate branches
      
       Percent |	Source code & Disassembly of branches for cycles:pu (217 samples)
      ---------------------------------------------------------------------------------
               :	branches():
          0.00 :	  40057a:       push   %rbp
          0.00 :	  40057b:       mov    %rsp,%rbp
          0.00 :	  40057e:       sub    $0x20,%rsp
          0.00 :	  400582:       mov    %rdi,-0x18(%rbp)
          0.00 :	  400586:       mov    %rsi,-0x20(%rbp)
          0.00 :	  40058a:       mov    -0x18(%rbp),%rax
          0.00 :	  40058e:       mov    %rax,-0x10(%rbp)
          0.00 :	  400592:       movq   $0x0,-0x8(%rbp)
          0.00 :	  40059a:       jmpq   400656 <branches+0xdc>
          1.84 :	  40059f:       mov    -0x10(%rbp),%rax	# +100.00%
          3.23 :	  4005a3:       and    $0x1,%eax
          1.84 :	  4005a6:       test   %rax,%rax
          0.00 :	  4005a9:       je     4005bf <branches+0x45>	# -54.50% (p:42.00%)
          0.46 :	  4005ab:       mov    0x200bbe(%rip),%rax        # 601170 <acc>
         12.90 :	  4005b2:       add    $0x1,%rax
          2.30 :	  4005b6:       mov    %rax,0x200bb3(%rip)        # 601170 <acc>
          0.46 :	  4005bd:       jmp    4005d1 <branches+0x57>	# -100.00% (p:100.00%)
          0.92 :	  4005bf:       mov    0x200baa(%rip),%rax        # 601170 <acc>	# +49.54%
         13.82 :	  4005c6:       sub    $0x1,%rax
          0.46 :	  4005ca:       mov    %rax,0x200b9f(%rip)        # 601170 <acc>
          2.30 :	  4005d1:       mov    -0x10(%rbp),%rax	# +50.46%
          0.46 :	  4005d5:       mov    %rax,%rdi
          0.46 :	  4005d8:       callq  400526 <lfsr>	# -100.00% (p:100.00%)
          0.00 :	  4005dd:       mov    %rax,-0x10(%rbp)	# +100.00%
          0.92 :	  4005e1:       mov    -0x18(%rbp),%rax
          0.00 :	  4005e5:       and    $0x1,%eax
          0.00 :	  4005e8:       test   %rax,%rax
          0.00 :	  4005eb:       je     4005ff <branches+0x85>	# -100.00% (p:100.00%)
          0.00 :	  4005ed:       mov    0x200b7c(%rip),%rax        # 601170 <acc>
          0.00 :	  4005f4:       shr    $0x2,%rax
          0.00 :	  4005f8:       mov    %rax,0x200b71(%rip)        # 601170 <acc>
          0.00 :	  4005ff:       mov    -0x10(%rbp),%rax	# +100.00%
          7.37 :	  400603:       and    $0x1,%eax
          3.69 :	  400606:       test   %rax,%rax
          0.00 :	  400609:       jne    400612 <branches+0x98>	# -59.25% (p:42.99%)
          1.84 :	  40060b:       mov    $0x1,%eax
         14.29 :	  400610:       jmp    400617 <branches+0x9d>	# -100.00% (p:100.00%)
          1.38 :	  400612:       mov    $0x0,%eax	# +57.65%
         10.14 :	  400617:       test   %al,%al	# +42.35%
          0.00 :	  400619:       je     40062f <branches+0xb5>	# -57.65% (p:100.00%)
          0.46 :	  40061b:       mov    0x200b4e(%rip),%rax        # 601170 <acc>
          2.76 :	  400622:       sub    $0x1,%rax
          0.00 :	  400626:       mov    %rax,0x200b43(%rip)        # 601170 <acc>
          0.46 :	  40062d:       jmp    400641 <branches+0xc7>	# -100.00% (p:100.00%)
          0.92 :	  40062f:       mov    0x200b3a(%rip),%rax        # 601170 <acc>	# +56.13%
          2.30 :	  400636:       add    $0x1,%rax
          0.92 :	  40063a:       mov    %rax,0x200b2f(%rip)        # 601170 <acc>
          0.92 :	  400641:       mov    -0x10(%rbp),%rax	# +43.87%
          2.30 :	  400645:       mov    %rax,%rdi
          0.00 :	  400648:       callq  400526 <lfsr>	# -100.00% (p:100.00%)
          0.00 :	  40064d:       mov    %rax,-0x10(%rbp)	# +100.00%
          1.84 :	  400651:       addq   $0x1,-0x8(%rbp)
          0.92 :	  400656:       mov    -0x8(%rbp),%rax
          5.07 :	  40065a:       cmp    -0x20(%rbp),%rax
          0.00 :	  40065e:       jb     40059f <branches+0x25>	# -100.00% (p:100.00%)
          0.00 :	  400664:       nop
          0.00 :	  400665:       leaveq
          0.00 :	  400666:       retq
      
      (Note: the --branch-filter u,any was used to avoid spurious target and
      branch points due to interrupts/faults, they show up as very small -/+
      annotations on 'weird' locations)
      
      Committer note:
      
      Please take a look at:
      
        http://vger.kernel.org/~acme/perf/annotate_basic_blocks.png
      
      To see the colors.
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Andi Kleen <andi@firstfloor.org>
      Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
      Cc: David Carrillo-Cisneros <davidcc@google.com>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: Kan Liang <kan.liang@intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Stephane Eranian <eranian@google.com>
      [ Moved sym->max_coverage to 'struct annotate', aka symbol__annotate(sym) ]
      Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      70fbe057
  9. 08 9月, 2016 3 次提交
  10. 05 9月, 2016 2 次提交