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perf trace: Don't relookup fields by name in each sample

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Instead do the lookups just when creating the tracepoints, initially for
the most common, raw_syscalls:sys_{enter,exit}.

It works by having evsel->priv have a per tracepoint structure with
entries for the fields, for direct access, with the offset and a
function to get the value from the sample, doing the swap if needed.

Using a simple workload that does M millions write syscalls, we go from:

 # perf stat -i -e cycles /tmp/oldperf trace ./sc_hello 100 > /dev/null

 Performance counter stats for '/tmp/oldperf trace ./sc_hello 100':

     8,366,771,459 cycles

       2.668025928 seconds time elapsed

 # perf stat -i -e cycles perf trace ./sc_hello 100 > /dev/null

 Performance counter stats for 'perf trace ./sc_hello 100':

     8,345,187,650 cycles

       2.631748425 seconds time elapsed

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-eyfhvoo510a5i10b27dnvm88@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Arnaldo Carvalho de Melo 2013-11-06 16:35:57 -03:00
parent a614d01bdd
commit 77170988ff
1 changed files with 188 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

199
tools/perf/builtin-trace.c
View File

@ -35,6 +35,189 @@
# define MADV_UNMERGEABLE 13
#endif
struct tp_field {
int offset;
union {
u64 (*integer)(struct tp_field *field, struct perf_sample *sample);
void *(*pointer)(struct tp_field *field, struct perf_sample *sample);
};
};
#define TP_UINT_FIELD(bits) \
static u64 tp_field__u##bits(struct tp_field *field, struct perf_sample *sample) \
{ \
return *(u##bits *)(sample->raw_data + field->offset); \
}
TP_UINT_FIELD(8);
TP_UINT_FIELD(16);
TP_UINT_FIELD(32);
TP_UINT_FIELD(64);
#define TP_UINT_FIELD__SWAPPED(bits) \
static u64 tp_field__swapped_u##bits(struct tp_field *field, struct perf_sample *sample) \
{ \
u##bits value = *(u##bits *)(sample->raw_data + field->offset); \
return bswap_##bits(value);\
}
TP_UINT_FIELD__SWAPPED(16);
TP_UINT_FIELD__SWAPPED(32);
TP_UINT_FIELD__SWAPPED(64);
static int tp_field__init_uint(struct tp_field *field,
struct format_field *format_field,
bool needs_swap)
{
field->offset = format_field->offset;
switch (format_field->size) {
case 1:
field->integer = tp_field__u8;
break;
case 2:
field->integer = needs_swap ? tp_field__swapped_u16 : tp_field__u16;
break;
case 4:
field->integer = needs_swap ? tp_field__swapped_u32 : tp_field__u32;
break;
case 8:
field->integer = needs_swap ? tp_field__swapped_u64 : tp_field__u64;
break;
default:
return -1;
}
return 0;
}
static void *tp_field__ptr(struct tp_field *field, struct perf_sample *sample)
{
return sample->raw_data + field->offset;
}
static int tp_field__init_ptr(struct tp_field *field, struct format_field *format_field)
{
field->offset = format_field->offset;
field->pointer = tp_field__ptr;
return 0;
}
struct syscall_tp {
struct tp_field id;
union {
struct tp_field args, ret;
};
};
static int perf_evsel__init_tp_uint_field(struct perf_evsel *evsel,
struct tp_field *field,
const char *name)
{
struct format_field *format_field = perf_evsel__field(evsel, name);
if (format_field == NULL)
return -1;
return tp_field__init_uint(field, format_field, evsel->needs_swap);
}
#define perf_evsel__init_sc_tp_uint_field(evsel, name) \
({ struct syscall_tp *sc = evsel->priv;\
perf_evsel__init_tp_uint_field(evsel, &sc->name, #name); })
static int perf_evsel__init_tp_ptr_field(struct perf_evsel *evsel,
struct tp_field *field,
const char *name)
{
struct format_field *format_field = perf_evsel__field(evsel, name);
if (format_field == NULL)
return -1;
return tp_field__init_ptr(field, format_field);
}
#define perf_evsel__init_sc_tp_ptr_field(evsel, name) \
({ struct syscall_tp *sc = evsel->priv;\
perf_evsel__init_tp_ptr_field(evsel, &sc->name, #name); })
static void perf_evsel__delete_priv(struct perf_evsel *evsel)
{
free(evsel->priv);
evsel->priv = NULL;
perf_evsel__delete(evsel);
}
static struct perf_evsel *perf_evsel__syscall_newtp(const char *direction,
void *handler, int idx)
{
struct perf_evsel *evsel = perf_evsel__newtp("raw_syscalls", direction, idx);
if (evsel) {
evsel->priv = malloc(sizeof(struct syscall_tp));
if (evsel->priv == NULL)
goto out_delete;
if (perf_evsel__init_sc_tp_uint_field(evsel, id))
goto out_delete;
evsel->handler = handler;
}
return evsel;
out_delete:
perf_evsel__delete_priv(evsel);
return NULL;
}
#define perf_evsel__sc_tp_uint(evsel, name, sample) \
({ struct syscall_tp *fields = evsel->priv; \
fields->name.integer(&fields->name, sample); })
#define perf_evsel__sc_tp_ptr(evsel, name, sample) \
({ struct syscall_tp *fields = evsel->priv; \
fields->name.pointer(&fields->name, sample); })
static int perf_evlist__add_syscall_newtp(struct perf_evlist *evlist,
void *sys_enter_handler,
void *sys_exit_handler)
{
int ret = -1;
int idx = evlist->nr_entries;
struct perf_evsel *sys_enter, *sys_exit;
sys_enter = perf_evsel__syscall_newtp("sys_enter", sys_enter_handler, idx++);
if (sys_enter == NULL)
goto out;
if (perf_evsel__init_sc_tp_ptr_field(sys_enter, args))
goto out_delete_sys_enter;
sys_exit = perf_evsel__syscall_newtp("sys_exit", sys_exit_handler, idx++);
if (sys_exit == NULL)
goto out_delete_sys_enter;
if (perf_evsel__init_sc_tp_uint_field(sys_exit, ret))
goto out_delete_sys_exit;
perf_evlist__add(evlist, sys_enter);
perf_evlist__add(evlist, sys_exit);
ret = 0;
out:
return ret;
out_delete_sys_exit:
perf_evsel__delete_priv(sys_exit);
out_delete_sys_enter:
perf_evsel__delete_priv(sys_enter);
goto out;
}
struct syscall_arg {
unsigned long val;
struct thread *thread;
@ -1392,7 +1575,7 @@ static int trace__sys_enter(struct trace *trace, struct perf_evsel *evsel,
void *args;
size_t printed = 0;
struct thread *thread;
int id = perf_evsel__intval(evsel, sample, "id");
int id = perf_evsel__sc_tp_uint(evsel, id, sample);
struct syscall *sc = trace__syscall_info(trace, evsel, id);
struct thread_trace *ttrace;
@ -1407,12 +1590,7 @@ static int trace__sys_enter(struct trace *trace, struct perf_evsel *evsel,
if (ttrace == NULL)
return -1;
args = perf_evsel__rawptr(evsel, sample, "args");
if (args == NULL) {
fprintf(trace->output, "Problems reading syscall arguments\n");
return -1;
}
args = perf_evsel__sc_tp_ptr(evsel, args, sample);
ttrace = thread->priv;
if (ttrace->entry_str == NULL) {
@ -1445,7 +1623,7 @@ static int trace__sys_exit(struct trace *trace, struct perf_evsel *evsel,
int ret;
u64 duration = 0;
struct thread *thread;
int id = perf_evsel__intval(evsel, sample, "id");
int id = perf_evsel__sc_tp_uint(evsel, id, sample);
struct syscall *sc = trace__syscall_info(trace, evsel, id);
struct thread_trace *ttrace;
@ -1463,7 +1641,7 @@ static int trace__sys_exit(struct trace *trace, struct perf_evsel *evsel,
if (trace->summary)
thread__update_stats(ttrace, id, sample);
ret = perf_evsel__intval(evsel, sample, "ret");
ret = perf_evsel__sc_tp_uint(evsel, ret, sample);
if (id == trace->audit.open_id && ret >= 0 && trace->last_vfs_getname) {
trace__set_fd_pathname(thread, ret, trace->last_vfs_getname);
@ -1675,8 +1853,7 @@ static int trace__run(struct trace *trace, int argc, const char **argv)
goto out;
}
if (perf_evlist__add_newtp(evlist, "raw_syscalls", "sys_enter", trace__sys_enter) ||
perf_evlist__add_newtp(evlist, "raw_syscalls", "sys_exit", trace__sys_exit))
if (perf_evlist__add_syscall_newtp(evlist, trace__sys_enter, trace__sys_exit))
goto out_error_tp;
perf_evlist__add_vfs_getname(evlist);