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perf annotate-data: Handle ADD instructions

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There are different patterns for percpu variable access using a constant
value added to the base.

  2aeb:  mov    -0x7da0f7e0(,%rax,8),%r14  # r14 = __per_cpu_offset[cpu]
  2af3:  mov    $0x34740,%rax              # rax = address of runqueues
* 2afa:  add    %rax,%r14                  # r14 = &per_cpu(runqueues, cpu)
  2bfd:  cmpl   $0x0,0x10(%r14)            # cpu_rq(cpu)->has_blocked_load
  2b03:  je     0x2b36

At the first instruction, r14 has the __per_cpu_offset.  And then rax
has an immediate value and then added to r14 to calculate the address of
a per-cpu variable.  So it needs to track the immediate values and ADD
instructions.

Similar but a little different case is to use "this_cpu_off" instead of
"__per_cpu_offset" for the current CPU.  This time the variable address
comes with PC-rel addressing.

  89:  mov     $0x34740,%rax                # rax = address of runqueues
* 90:  add     %gs:0x7f015f60(%rip),%rax    # 19a78  <this_cpu_off>
  98:  incl    0xd8c(%rax)                  # cpu_rq(cpu)->sched_count

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20240319055115.4063940-21-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Namhyung Kim 2024-03-18 22:51:12 -07:00 • committed by Arnaldo Carvalho de Melo
commit eb9190afae
1 changed files with 105 additions and 2 deletions
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