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perf report: Add support for profiling JIT generated code

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This patch adds support for profiling JIT generated code to 'perf
report'. A JIT compiler is required to generate a "/tmp/perf-$PID.map"
symbols map that is parsed when looking and displaying symbols.

Thanks to Peter Zijlstra for his help with this patch!

Example "perf report" output with the Jato JIT:

 #
 # (40311 samples)
 #
 # Overhead           Command  Shared Object              Symbol
 # ........  ................  .........................  ......
 #
     97.80%              jato  /tmp/perf-11915.map        [.] Fibonacci.fib(I)I
      0.56%              jato  00000000b7fa023b           0x000000b7fa023b
      0.45%              jato  /tmp/perf-11915.map        [.] Fibonacci.main([Ljava/lang/String;)V
      0.38%              jato  [kernel]                   [k] get_page_from_freelist
      0.06%              jato  [kernel]                   [k] kunmap_atomic
      0.05%              jato  ./jato                     [.] utf8Hash
      0.04%              jato  ./jato                     [.] executeJava
      0.04%              jato  ./jato                     [.] defineClass

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: a.p.zijlstra@chello.nl
Cc: acme@redhat.com
LKML-Reference: <Pine.LNX.4.64.0906082111590.12407@melkki.cs.Helsinki.FI>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Pekka Enberg
2009-06-08 21:12:48 +03:00
committed by Ingo Molnar
parent dab5855b12
commit 80d496be89
2 changed files with 79 additions and 1 deletions
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65
tools/perf/util/symbol.c
View File

@@ -220,6 +220,68 @@ out_failure:
return -1;
}
static int dso__load_perf_map(struct dso *self, symbol_filter_t filter, int verbose)
{
char *line = NULL;
size_t n;
FILE *file;
int nr_syms = 0;
file = fopen(self->name, "r");
if (file == NULL)
goto out_failure;
while (!feof(file)) {
__u64 start, size;
struct symbol *sym;
int line_len, len;
line_len = getline(&line, &n, file);
if (line_len < 0)
break;
if (!line)
goto out_failure;
line[--line_len] = '\0'; /* \n */
len = hex2u64(line, &start);
len++;
if (len + 2 >= line_len)
continue;
len += hex2u64(line + len, &size);
len++;
if (len + 2 >= line_len)
continue;
sym = symbol__new(start, size, line + len,
self->sym_priv_size, start, verbose);
if (sym == NULL)
goto out_delete_line;
if (filter && filter(self, sym))
symbol__delete(sym, self->sym_priv_size);
else {
dso__insert_symbol(self, sym);
nr_syms++;
}
}
free(line);
fclose(file);
return nr_syms;
out_delete_line:
free(line);
out_failure:
return -1;
}
/**
* elf_symtab__for_each_symbol - iterate thru all the symbols
*
@@ -507,6 +569,9 @@ int dso__load(struct dso *self, symbol_filter_t filter, int verbose)
if (!name)
return -1;
if (strncmp(self->name, "/tmp/perf-", 10) == 0)
return dso__load_perf_map(self, filter, verbose);
more:
do {
switch (variant) {