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perf: Store trace event name/id pairs in perf.data

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The trace event name<->id mapping is dynamic for each kernel
compile. In order for perf.data to be useable outside the actual
system, we thus need to store a table of this mapping for later
use.

This patch adds this table to perf.data, and provides helper
functions for lookup up fields from this table.

To avoid mistakes, lookup-from-table is kept completely seprate
from lookup-from-local-debugfs.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20090912130405.6960d099@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Arjan van de Ven
2009-09-12 07:52:51 +02:00
committed by Ingo Molnar
parent 393b2ad8c7
commit 8755a8f27a
3 changed files with 90 additions and 0 deletions
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59
tools/perf/util/header.c
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@ -86,6 +86,44 @@ void perf_header__add_attr(struct perf_header *self,
self->attr[pos] = attr;
}
struct perf_trace_event_type {
u64 event_id;
char name[64];
};
static int event_count;
static struct perf_trace_event_type *events;
void perf_header__push_event(u64 id, const char *name)
{
if (strlen(name) > 64)
printf("Event %s will be truncated\n", name);
if (!events) {
events = malloc(sizeof(struct perf_trace_event_type));
if (!events)
die("nomem");
} else {
events = realloc(events, (event_count + 1) * sizeof(struct perf_trace_event_type));
if (!events)
die("nomem");
}
memset(&events[event_count], 0, sizeof(struct perf_trace_event_type));
events[event_count].event_id = id;
strncpy(events[event_count].name, name, 63);
event_count++;
}
char *perf_header__find_event(u64 id)
{
int i;
for (i = 0 ; i < event_count; i++) {
if (events[i].event_id == id)
return events[i].name;
}
return NULL;
}
static const char *__perf_magic = "PERFFILE";
#define PERF_MAGIC (*(u64 *)__perf_magic)
@ -106,6 +144,7 @@ struct perf_file_header {
u64 attr_size;
struct perf_file_section attrs;
struct perf_file_section data;
struct perf_file_section event_types;
};
static void do_write(int fd, void *buf, size_t size)
@ -154,6 +193,11 @@ void perf_header__write(struct perf_header *self, int fd)
do_write(fd, &f_attr, sizeof(f_attr));
}
self->event_offset = lseek(fd, 0, SEEK_CUR);
self->event_size = event_count * sizeof(struct perf_trace_event_type);
if (events)
do_write(fd, events, self->event_size);
self->data_offset = lseek(fd, 0, SEEK_CUR);
@ -169,6 +213,10 @@ void perf_header__write(struct perf_header *self, int fd)
.offset = self->data_offset,
.size = self->data_size,
},
.event_types = {
.offset = self->event_offset,
.size = self->event_size,
},
};
lseek(fd, 0, SEEK_SET);
@ -234,6 +282,17 @@ struct perf_header *perf_header__read(int fd)
lseek(fd, tmp, SEEK_SET);
}
if (f_header.event_types.size) {
lseek(fd, f_header.event_types.offset, SEEK_SET);
events = malloc(f_header.event_types.size);
if (!events)
die("nomem");
do_read(fd, events, f_header.event_types.size);
event_count = f_header.event_types.size / sizeof(struct perf_trace_event_type);
}
self->event_offset = f_header.event_types.offset;
self->event_size = f_header.event_types.size;
self->data_offset = f_header.data.offset;
self->data_size = f_header.data.size;