1. 16 Jun, 2023 1 commit
    • Ian Rogers's avatar
      perf srcline: Fix handling of inline functions · e90208e9
      Ian Rogers authored
      We write an address then a ',' to addr2line. With inline data we
      generally get back (// are my comments):
      0x1234    // address
      foo       // function name
      foo.c:123 // filename:line
      bar       // function name
      bar.c:123 // filename:line
      0x000000000000000 // sentinel address created by ','
      ??        // unknown function name
      ??:0      // unknown filename:line
      
      The code was assuming the inline data also had the address, which is
      incorrect. This means the first inline function name (bar above) needs
      to be checked to see if it is the sentinel, otherwise to be treated as
      a function name. The regression was caused by the addition of
      addresses as the kernel is reporting a symbol at address 0 (used by
      GNU binutils when it interprets ',').
      
      Committer testing:
      
      Using:
      
        # perf trace --call-graph=dwarf -e lock:contention_*
        <SNIP>
        1244.615 TaskCon~ller #/2645281 lock:contention_begin(lock_addr: 0xffff8e6748da5ab0, flags: 2)
                                             __preempt_count_dec_and_test (inlined)
                                             trace_contention_begin (inlined)
                                             trace_contention_begin (inlined)
                                             rwsem_down_read_slowpath ([kernel.kallsyms])
                                             __preempt_count_dec_and_test (inlined)
                                             trace_contention_begin (inlined)
                                             trace_contention_begin (inlined)
                                             rwsem_down_read_slowpath ([kernel.kallsyms])
                                             __down_read_common (inlined)
                                             __down_read (inlined)
                                             down_read ([kernel.kallsyms])
                                             arch_static_branch (inlined)
                                             static_key_false (inlined)
                                             __mmap_lock_trace_acquire_returned (inlined)
                                             mmap_read_lock (inlined)
                                             do_user_addr_fault ([kernel.kallsyms])
                                             arch_local_irq_disable (inlined)
                                             handle_page_fault (inlined)
                                             exc_page_fault ([kernel.kallsyms])
                                             asm_exc_page_fault ([kernel.kallsyms])
                                             [0x4def008] (/usr/lib64/firefox/libxul.so)
        1244.619 TaskCon~ller #/2645281 lock:contention_end(lock_addr: 0xffff8e6748da5ab0)
                                             __preempt_count_dec_and_test (inlined)
                                             trace_contention_end (inlined)
                                             trace_contention_end (inlined)
                                             rwsem_down_read_slowpath ([kernel.kallsyms])
                                             __preempt_count_dec_and_test (inlined)
                                             trace_contention_end (inlined)
                                             trace_contention_end (inlined)
                                             rwsem_down_read_slowpath ([kernel.kallsyms])
                                             __down_read_common (inlined)
                                             __down_read (inlined)
                                             down_read ([kernel.kallsyms])
                                             arch_static_branch (inlined)
                                             static_key_false (inlined)
                                             __mmap_lock_trace_acquire_returned (inlined)
                                             mmap_read_lock (inlined)
                                             do_user_addr_fault ([kernel.kallsyms])
                                             arch_local_irq_disable (inlined)
                                             handle_page_fault (inlined)
                                             exc_page_fault ([kernel.kallsyms])
                                             asm_exc_page_fault ([kernel.kallsyms])
        <SNIP>
      
      Fixes: 8dc26b6f ("perf srcline: Make sentinel reading for binutils addr2line more robust")
      Reported-by: default avatarArnaldo Carvalho de Melo <acme@kernel.org>
      Signed-off-by: default avatarIan Rogers <irogers@google.com>
      Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Ian Rogers <irogers@google.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: llvm@lists.linux.dev
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Nathan Chancellor <nathan@kernel.org>
      Cc: Nick Desaulniers <ndesaulniers@google.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Tom Rix <trix@redhat.com>
      Link: https://lore.kernel.org/r/20230615025041.1982072-1-irogers@google.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      e90208e9
  2. 14 Jun, 2023 30 commits
  3. 13 Jun, 2023 2 commits
  4. 12 Jun, 2023 7 commits