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Ravi Bangoria 3149733584 perf annotate: Add fusion logic for AMD microarchs

AMD family 15h and above microarchs fuse a subset of cmp/test/ALU
instructions with branch instructions[1][2]. Add perf annotate
fused instruction support for these microarchs.

Before:
         │       testb  $0x80,0x51(%rax)
         │    ┌──jne    5b3
    0.78 │    │  mov    %r13,%rdi
         │    │→ callq  mark_page_accessed
    1.08 │5b3:└─→mov    0x8(%r13),%rax

After:
         │    ┌──testb  $0x80,0x51(%rax)
         │    ├──jne    5b3
    0.78 │    │  mov    %r13,%rdi
         │    │→ callq  mark_page_accessed
    1.08 │5b3:└─→mov    0x8(%r13),%rax

[1] https://bugzilla.kernel.org/attachment.cgi?id=298553
[2] https://bugzilla.kernel.org/attachment.cgi?id=298555

Committer testing:

On a:

  $ grep -m1 "model name" /proc/cpuinfo
  model name	: AMD Ryzen 9 3900X 12-Core Processor
  $

  Samples: 44K of event 'cycles', 4000 Hz, Event count (approx.): 7533249650
  _int_malloc  /usr/lib64/libc-2.33.so [Percent: local period]
  Percent│    ┌──test   %eax,%eax
         │    ├──jne    884
         │    │↓ jmpq   943
         │    │  nop
         │878:│  add    $0x10,%rdx
    0.64 │    │  add    %eax,%eax
    0.57 │    │↓ je     cc9
    0.77 │884:└─→test   %esi,%eax
         │     ↑ je     878
         │       mov    0x18(%rdx),%r15

Reported-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https //lore.kernel.org/r/20210911043854.8373-2-ravi.bangoria@amd.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

2021-09-15 17:54:52 -03:00

accounting

…

arch

tools headers UAPI: Sync x86's asm/kvm.h with the kernel sources

2021-09-10 18:15:22 -03:00

bootconfig

tools/bootconfig: Show whole test command for each test case

2021-09-08 15:29:16 -04:00

bpf

Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

2021-07-31 11:23:26 -07:00