No need to load symbols in a DSO when injecting build-id. I guess the
reason was to check the DSO is a special file like anon files. Use some
helper functions in map.c to check them before reading build-id. Also
pass sample event's cpumode to a new build-id event.
It brought a speedup in the benchmark of 25 -> 21 msec on my laptop.
Also the memory usage (Max RSS) went down by ~200 KB.
# Running 'internals/inject-build-id' benchmark:
Average build-id injection took: 21.389 msec (+- 0.138 msec)
Average time per event: 2.097 usec (+- 0.014 usec)
Average memory usage: 8225 KB (+- 0 KB)
Committer notes:
Before:
$ perf stat -r5 perf bench internals inject-build-id > /dev/null
Performance counter stats for 'perf bench internals inject-build-id' (5 runs):
4,020.56 msec task-clock:u # 1.271 CPUs utilized ( +- 0.74% )
0 context-switches:u # 0.000 K/sec
0 cpu-migrations:u # 0.000 K/sec
123,354 page-faults:u # 0.031 M/sec ( +- 0.81% )
7,119,951,568 cycles:u # 1.771 GHz ( +- 1.74% ) (83.27%)
230,086,969 stalled-cycles-frontend:u # 3.23% frontend cycles idle ( +- 1.97% ) (83.41%)
1,168,298,765 stalled-cycles-backend:u # 16.41% backend cycles idle ( +- 1.13% ) (83.44%)
11,173,083,669 instructions:u # 1.57 insn per cycle
# 0.10 stalled cycles per insn ( +- 1.58% ) (83.31%)
2,413,908,936 branches:u # 600.392 M/sec ( +- 1.69% ) (83.26%)
46,576,289 branch-misses:u # 1.93% of all branches ( +- 2.20% ) (83.31%)
3.1638 +- 0.0309 seconds time elapsed ( +- 0.98% )
$
After:
$ perf stat -r5 perf bench internals inject-build-id > /dev/null
Performance counter stats for 'perf bench internals inject-build-id' (5 runs):
2,379.94 msec task-clock:u # 1.473 CPUs utilized ( +- 0.18% )
0 context-switches:u # 0.000 K/sec
0 cpu-migrations:u # 0.000 K/sec
62,584 page-faults:u # 0.026 M/sec ( +- 0.07% )
2,372,389,668 cycles:u # 0.997 GHz ( +- 0.29% ) (83.14%)
106,937,862 stalled-cycles-frontend:u # 4.51% frontend cycles idle ( +- 4.89% ) (83.20%)
581,697,915 stalled-cycles-backend:u # 24.52% backend cycles idle ( +- 0.71% ) (83.47%)
3,659,692,199 instructions:u # 1.54 insn per cycle
# 0.16 stalled cycles per insn ( +- 0.10% ) (83.63%)
791,372,961 branches:u # 332.518 M/sec ( +- 0.27% ) (83.39%)
10,648,083 branch-misses:u # 1.35% of all branches ( +- 0.22% ) (83.16%)
1.61570 +- 0.00172 seconds time elapsed ( +- 0.11% )
$
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Original-patch-by: Stephane Eranian <eranian@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/r/20201012070214.2074921-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
#include "util/synthetic-events.h"
#include "util/thread.h"
#include "util/namespaces.h"
-#include <linux/err.h>
+#include <linux/err.h>
#include <subcmd/parse-options.h>
+#include <uapi/linux/mman.h> /* To get things like MAP_HUGETLB even on older libc headers */
#include <linux/list.h>
#include <errno.h>
}
static int dso__inject_build_id(struct dso *dso, struct perf_tool *tool,
- struct machine *machine)
+ struct machine *machine, u8 cpumode, u32 flags)
{
- u16 misc = PERF_RECORD_MISC_USER;
int err;
+ if (is_anon_memory(dso->long_name) || flags & MAP_HUGETLB)
+ return 0;
+ if (is_no_dso_memory(dso->long_name))
+ return 0;
+
if (dso__read_build_id(dso) < 0) {
pr_debug("no build_id found for %s\n", dso->long_name);
return -1;
}
- if (dso->kernel)
- misc = PERF_RECORD_MISC_KERNEL;
-
- err = perf_event__synthesize_build_id(tool, dso, misc, perf_event__repipe,
- machine);
+ err = perf_event__synthesize_build_id(tool, dso, cpumode,
+ perf_event__repipe, machine);
if (err) {
pr_err("Can't synthesize build_id event for %s\n", dso->long_name);
return -1;
if (thread__find_map(thread, sample->cpumode, sample->ip, &al)) {
if (!al.map->dso->hit) {
al.map->dso->hit = 1;
- if (map__load(al.map) >= 0) {
- dso__inject_build_id(al.map->dso, tool, machine);
- /*
- * If this fails, too bad, let the other side
- * account this as unresolved.
- */
- } else {
-#ifdef HAVE_LIBELF_SUPPORT
- pr_warning("no symbols found in %s, maybe "
- "install a debug package?\n",
- al.map->dso->long_name);
-#endif
- }
+ dso__inject_build_id(al.map->dso, tool, machine,
+ sample->cpumode, al.map->flags);
}
}
static void __maps__insert(struct maps *maps, struct map *map);
-static inline int is_anon_memory(const char *filename, u32 flags)
-{
- return flags & MAP_HUGETLB ||
- !strcmp(filename, "//anon") ||
- !strncmp(filename, "/dev/zero", sizeof("/dev/zero") - 1) ||
- !strncmp(filename, "/anon_hugepage", sizeof("/anon_hugepage") - 1);
-}
-
-static inline int is_no_dso_memory(const char *filename)
-{
- return !strncmp(filename, "[stack", 6) ||
- !strncmp(filename, "/SYSV",5) ||
- !strcmp(filename, "[heap]");
-}
-
static inline int is_android_lib(const char *filename)
{
return strstarts(filename, "/data/app-lib/") ||
int anon, no_dso, vdso, android;
android = is_android_lib(filename);
- anon = is_anon_memory(filename, flags);
+ anon = is_anon_memory(filename) || flags & MAP_HUGETLB;
vdso = is_vdso_map(filename);
no_dso = is_no_dso_memory(filename);
map->prot = prot;
return strncmp(name, "bpf_trampoline_", sizeof("bpf_trampoline_") - 1) == 0 ||
strncmp(name, "bpf_dispatcher_", sizeof("bpf_dispatcher_") - 1) == 0;
}
+
+static inline int is_anon_memory(const char *filename)
+{
+ return !strcmp(filename, "//anon") ||
+ !strncmp(filename, "/dev/zero", sizeof("/dev/zero") - 1) ||
+ !strncmp(filename, "/anon_hugepage", sizeof("/anon_hugepage") - 1);
+}
+
+static inline int is_no_dso_memory(const char *filename)
+{
+ return !strncmp(filename, "[stack", 6) ||
+ !strncmp(filename, "/SYSV", 5) ||
+ !strcmp(filename, "[heap]");
+}
#endif /* __PERF_MAP_H */
projects / linux-2.6-microblaze.git / commitdiff