• David Ahern's avatar
    perf kvm: Guest userspace samples should not be lumped with host uspace · 7c0f4a41
    David Ahern authored
    e.g., perf kvm --host  --guest report -i perf.data --stdio -D
    shows:
    
    1 599127912065356 0x143b8 [0x48]: PERF_RECORD_SAMPLE(IP, 5): 5671/5676: 0x7fdf95a061c0 period: 1 addr: 0
    ... chain: nr:2
    .....  0: ffffffffffffff80
    .....  1: fffffffffffffe00
     ... thread: qemu-kvm:5671
     ...... dso: <not found>
    
    (IP, 5) means sample in guest userspace. Those samples should not be lumped
    into the VMM's host thread. i.e, the report output:
    
        56.86%  qemu-kvm  [unknown]         [u] 0x00007fdf95a061c0
    
    With this patch the output emphasizes it is a guest userspace hit:
    
        56.86%  [guest/5671]  [unknown]         [u] 0x00007fdf95a061c0
    
    Looking at 3 VMs (2 64-bit, 1 32-bit) with each running a CPU bound
    process (openssl speed), perf report currently shows:
    
      93.84%  117726   qemu-kvm  [unknown]   [u] 0x00007fd7dcaea8e5
    
    which is wrong. With this patch you get:
    
      31.50%   39258   [guest/18772]  [unknown]   [u] 0x00007fd7dcaea8e5
      31.50%   39236   [guest/11230]  [unknown]   [u] 0x0000000000a57340
      30.84%   39232   [guest/18395]  [unknown]   [u] 0x00007f66f641e107
    Tested-by: default avatarJiri Olsa <jolsa@redhat.com>
    Signed-off-by: default avatarDavid Ahern <dsahern@gmail.com>
    Cc: Frederic Weisbecker <fweisbec@gmail.com>
    Cc: Ingo Molnar <mingo@kernel.org>
    Cc: Jiri Olsa <jolsa@redhat.com>
    Cc: Namhyung Kim <namhyung@kernel.org>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Link: http://lkml.kernel.org/r/1342826756-64663-4-git-send-email-dsahern@gmail.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
    7c0f4a41
session.c 42.3 KB