Message ID | 20190228050643.958685-9-songliubraving@fb.com |
---|---|
State | Changes Requested |
Delegated to: | BPF Maintainers |
Headers | show |
Series | perf annotation of BPF programs | expand |
On Wed, Feb 27, 2019 at 09:06:36PM -0800, Song Liu wrote: > btf contains information necessary to annotate bpf programs. This patch > saves btf for bpf programs loaded in the system. > > Signed-off-by: Song Liu <songliubraving@fb.com> > --- > tools/perf/util/bpf-event.c | 24 ++++++++++++++ > tools/perf/util/bpf-event.h | 7 ++++ > tools/perf/util/env.c | 65 +++++++++++++++++++++++++++++++++++++ > tools/perf/util/env.h | 4 +++ > 4 files changed, 100 insertions(+) > > diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c > index ce81b2c43a51..370b830f2433 100644 > --- a/tools/perf/util/bpf-event.c > +++ b/tools/perf/util/bpf-event.c > @@ -34,6 +34,29 @@ int machine__process_bpf_event(struct machine *machine __maybe_unused, > return 0; > } > > +static int perf_env__fetch_btf(struct perf_env *env, > + u32 btf_id, > + struct btf *btf) > +{ > + struct btf_node *node; > + u32 data_size; > + const void *data; > + > + data = btf__get_raw_data(btf, &data_size); > + > + node = malloc(data_size + sizeof(struct btf_node)); > + > + if (!node) > + return -1; > + > + node->id = btf_id; > + node->data_size = data_size; > + memcpy(node->data, data, data_size); why don't we store just struct btf itself? thanks, jirka
On Wed, Feb 27, 2019 at 09:06:36PM -0800, Song Liu wrote: > btf contains information necessary to annotate bpf programs. This patch > saves btf for bpf programs loaded in the system. > > Signed-off-by: Song Liu <songliubraving@fb.com> > --- > tools/perf/util/bpf-event.c | 24 ++++++++++++++ > tools/perf/util/bpf-event.h | 7 ++++ > tools/perf/util/env.c | 65 +++++++++++++++++++++++++++++++++++++ > tools/perf/util/env.h | 4 +++ > 4 files changed, 100 insertions(+) > > diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c > index ce81b2c43a51..370b830f2433 100644 > --- a/tools/perf/util/bpf-event.c > +++ b/tools/perf/util/bpf-event.c > @@ -34,6 +34,29 @@ int machine__process_bpf_event(struct machine *machine __maybe_unused, > return 0; > } > > +static int perf_env__fetch_btf(struct perf_env *env, > + u32 btf_id, > + struct btf *btf) > +{ > + struct btf_node *node; > + u32 data_size; > + const void *data; > + > + data = btf__get_raw_data(btf, &data_size); > + > + node = malloc(data_size + sizeof(struct btf_node)); > + extra new line > + if (!node) > + return -1; > + > + node->id = btf_id; > + node->data_size = data_size; > + memcpy(node->data, data, data_size); > + > + perf_env__insert_btf(env, node); > + return 0; > +} SNIP
> On Mar 4, 2019, at 5:52 AM, Jiri Olsa <jolsa@redhat.com> wrote: > > On Wed, Feb 27, 2019 at 09:06:36PM -0800, Song Liu wrote: >> btf contains information necessary to annotate bpf programs. This patch >> saves btf for bpf programs loaded in the system. >> >> Signed-off-by: Song Liu <songliubraving@fb.com> >> --- >> tools/perf/util/bpf-event.c | 24 ++++++++++++++ >> tools/perf/util/bpf-event.h | 7 ++++ >> tools/perf/util/env.c | 65 +++++++++++++++++++++++++++++++++++++ >> tools/perf/util/env.h | 4 +++ >> 4 files changed, 100 insertions(+) >> >> diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c >> index ce81b2c43a51..370b830f2433 100644 >> --- a/tools/perf/util/bpf-event.c >> +++ b/tools/perf/util/bpf-event.c >> @@ -34,6 +34,29 @@ int machine__process_bpf_event(struct machine *machine __maybe_unused, >> return 0; >> } >> >> +static int perf_env__fetch_btf(struct perf_env *env, >> + u32 btf_id, >> + struct btf *btf) >> +{ >> + struct btf_node *node; >> + u32 data_size; >> + const void *data; >> + >> + data = btf__get_raw_data(btf, &data_size); >> + >> + node = malloc(data_size + sizeof(struct btf_node)); >> + >> + if (!node) >> + return -1; >> + >> + node->id = btf_id; >> + node->data_size = data_size; >> + memcpy(node->data, data, data_size); > > why don't we store just struct btf itself? > > thanks, > jirka In current libbpf design, definition of "struct btf" is private to tools/lib/bpf/btf.c. So we cannot copy the struct itself. Thanks, Song
On Mon, Mar 04, 2019 at 07:43:50PM +0000, Song Liu wrote: > > > > On Mar 4, 2019, at 5:52 AM, Jiri Olsa <jolsa@redhat.com> wrote: > > > > On Wed, Feb 27, 2019 at 09:06:36PM -0800, Song Liu wrote: > >> btf contains information necessary to annotate bpf programs. This patch > >> saves btf for bpf programs loaded in the system. > >> > >> Signed-off-by: Song Liu <songliubraving@fb.com> > >> --- > >> tools/perf/util/bpf-event.c | 24 ++++++++++++++ > >> tools/perf/util/bpf-event.h | 7 ++++ > >> tools/perf/util/env.c | 65 +++++++++++++++++++++++++++++++++++++ > >> tools/perf/util/env.h | 4 +++ > >> 4 files changed, 100 insertions(+) > >> > >> diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c > >> index ce81b2c43a51..370b830f2433 100644 > >> --- a/tools/perf/util/bpf-event.c > >> +++ b/tools/perf/util/bpf-event.c > >> @@ -34,6 +34,29 @@ int machine__process_bpf_event(struct machine *machine __maybe_unused, > >> return 0; > >> } > >> > >> +static int perf_env__fetch_btf(struct perf_env *env, > >> + u32 btf_id, > >> + struct btf *btf) > >> +{ > >> + struct btf_node *node; > >> + u32 data_size; > >> + const void *data; > >> + > >> + data = btf__get_raw_data(btf, &data_size); > >> + > >> + node = malloc(data_size + sizeof(struct btf_node)); > >> + > >> + if (!node) > >> + return -1; > >> + > >> + node->id = btf_id; > >> + node->data_size = data_size; > >> + memcpy(node->data, data, data_size); > > > > why don't we store just struct btf itself? > > > > thanks, > > jirka > > In current libbpf design, definition of "struct btf" is private > to tools/lib/bpf/btf.c. So we cannot copy the struct itself. ok jirka
diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c index ce81b2c43a51..370b830f2433 100644 --- a/tools/perf/util/bpf-event.c +++ b/tools/perf/util/bpf-event.c @@ -34,6 +34,29 @@ int machine__process_bpf_event(struct machine *machine __maybe_unused, return 0; } +static int perf_env__fetch_btf(struct perf_env *env, + u32 btf_id, + struct btf *btf) +{ + struct btf_node *node; + u32 data_size; + const void *data; + + data = btf__get_raw_data(btf, &data_size); + + node = malloc(data_size + sizeof(struct btf_node)); + + if (!node) + return -1; + + node->id = btf_id; + node->data_size = data_size; + memcpy(node->data, data, data_size); + + perf_env__insert_btf(env, node); + return 0; +} + /* * Synthesize PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT for one bpf * program. One PERF_RECORD_BPF_EVENT is generated for the program. And @@ -113,6 +136,7 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, goto out; } has_btf = true; + perf_env__fetch_btf(env, info->btf_id, btf); } /* Synthesize PERF_RECORD_KSYMBOL */ diff --git a/tools/perf/util/bpf-event.h b/tools/perf/util/bpf-event.h index fad932f7404f..b9ec394dc7c7 100644 --- a/tools/perf/util/bpf-event.h +++ b/tools/perf/util/bpf-event.h @@ -16,6 +16,13 @@ struct bpf_prog_info_node { struct rb_node rb_node; }; +struct btf_node { + struct rb_node rb_node; + u32 id; + u32 data_size; + char data[]; +}; + #ifdef HAVE_LIBBPF_SUPPORT int machine__process_bpf_event(struct machine *machine, union perf_event *event, struct perf_sample *sample); diff --git a/tools/perf/util/env.c b/tools/perf/util/env.c index cdda46f2633f..9e4ee7b0a3d1 100644 --- a/tools/perf/util/env.c +++ b/tools/perf/util/env.c @@ -63,6 +63,57 @@ struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env, return node; } +void perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node) +{ + struct rb_node *parent = NULL; + __u32 btf_id = btf_node->id; + struct btf_node *node; + struct rb_node **p; + + down_write(&env->bpf_progs.lock); + p = &env->bpf_progs.btfs.rb_node; + + while (*p != NULL) { + parent = *p; + node = rb_entry(parent, struct btf_node, rb_node); + if (btf_id < node->id) { + p = &(*p)->rb_left; + } else if (btf_id > node->id) { + p = &(*p)->rb_right; + } else { + pr_debug("duplicated btf %u\n", btf_id); + goto out; + } + } + + rb_link_node(&btf_node->rb_node, parent, p); + rb_insert_color(&btf_node->rb_node, &env->bpf_progs.btfs); +out: + up_write(&env->bpf_progs.lock); +} + +struct btf_node *perf_env__find_btf(struct perf_env *env, __u32 btf_id) +{ + struct btf_node *node = NULL; + struct rb_node *n; + + down_read(&env->bpf_progs.lock); + n = env->bpf_progs.btfs.rb_node; + + while (n) { + node = rb_entry(n, struct btf_node, rb_node); + if (btf_id < node->id) + n = n->rb_left; + else if (btf_id > node->id) + n = n->rb_right; + else + break; + } + + up_read(&env->bpf_progs.lock); + return node; +} + /* purge data in bpf_progs.infos tree */ static void perf_env__purge_bpf(struct perf_env *env) { @@ -82,6 +133,19 @@ static void perf_env__purge_bpf(struct perf_env *env) rb_erase_init(&node->rb_node, root); free(node); } + + root = &env->bpf_progs.btfs; + next = rb_first(root); + + while (next) { + struct btf_node *node; + + node = rb_entry(next, struct btf_node, rb_node); + next = rb_next(&node->rb_node); + rb_erase_init(&node->rb_node, root); + free(node); + } + up_write(&env->bpf_progs.lock); } @@ -119,6 +183,7 @@ void perf_env__exit(struct perf_env *env) void perf_env__init(struct perf_env *env) { env->bpf_progs.infos = RB_ROOT; + env->bpf_progs.btfs = RB_ROOT; init_rwsem(&env->bpf_progs.lock); } diff --git a/tools/perf/util/env.h b/tools/perf/util/env.h index e034e5b438e3..c3e48504e834 100644 --- a/tools/perf/util/env.h +++ b/tools/perf/util/env.h @@ -74,10 +74,12 @@ struct perf_env { struct { struct rw_semaphore lock; struct rb_root infos; + struct rb_root btfs; } bpf_progs; }; struct bpf_prog_info_node; +struct btf_node; extern struct perf_env perf_env; @@ -98,4 +100,6 @@ void perf_env__insert_bpf_prog_info(struct perf_env *env, struct bpf_prog_info_node *info_node); struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env, __u32 prog_id); +void perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node); +struct btf_node *perf_env__find_btf(struct perf_env *env, __u32 btf_id); #endif /* __PERF_ENV_H */
btf contains information necessary to annotate bpf programs. This patch saves btf for bpf programs loaded in the system. Signed-off-by: Song Liu <songliubraving@fb.com> --- tools/perf/util/bpf-event.c | 24 ++++++++++++++ tools/perf/util/bpf-event.h | 7 ++++ tools/perf/util/env.c | 65 +++++++++++++++++++++++++++++++++++++ tools/perf/util/env.h | 4 +++ 4 files changed, 100 insertions(+)