| Message ID | 20190226002019.3748539-7-songliubraving@fb.com |
|---|---|
| State | Changes Requested |
| Delegated to: | BPF Maintainers |
| Headers | show |
| Series | perf annotation of BPF programs | expand |
On Mon, Feb 25, 2019 at 04:20:10PM -0800, Song Liu wrote: > bpf_prog_info contains information necessary to annotate bpf programs. > This patch saves bpf_prog_info for bpf programs loaded in the system. > > Signed-off-by: Song Liu <songliubraving@fb.com> > --- > tools/perf/util/bpf-event.c | 32 +++++++++++++- > tools/perf/util/bpf-event.h | 7 ++- > tools/perf/util/env.c | 85 +++++++++++++++++++++++++++++++++++++ > tools/perf/util/env.h | 17 ++++++++ > 4 files changed, 139 insertions(+), 2 deletions(-) > > diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c > index ff7ee149ec46..ce81b2c43a51 100644 > --- a/tools/perf/util/bpf-event.c > +++ b/tools/perf/util/bpf-event.c > @@ -10,6 +10,7 @@ > #include "debug.h" > #include "symbol.h" > #include "machine.h" > +#include "env.h" > #include "session.h" > > #define ptr_to_u64(ptr) ((__u64)(unsigned long)(ptr)) > @@ -54,17 +55,28 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, > struct bpf_event *bpf_event = &event->bpf_event; > struct bpf_prog_info_linear *info_linear; > struct perf_tool *tool = session->tool; > + struct bpf_prog_info_node *info_node; > struct bpf_prog_info *info; > struct btf *btf = NULL; > bool has_btf = false; > + struct perf_env *env; > u32 sub_prog_cnt, i; > int err = 0; > u64 arrays; > > + /* > + * for perf-record and perf-report use header.env; > + * otherwise, use global perf_env. > + */ > + env = session->data ? &session->header.env : &perf_env; > + > arrays = 1UL << BPF_PROG_INFO_JITED_KSYMS; > arrays |= 1UL << BPF_PROG_INFO_JITED_FUNC_LENS; > arrays |= 1UL << BPF_PROG_INFO_FUNC_INFO; > arrays |= 1UL << BPF_PROG_INFO_PROG_TAGS; > + arrays |= 1UL << BPF_PROG_INFO_JITED_INSNS; > + arrays |= 1UL << BPF_PROG_INFO_LINE_INFO; > + arrays |= 1UL << BPF_PROG_INFO_JITED_LINE_INFO; > > info_linear = bpf_program__get_prog_info_linear(fd, arrays); > if (IS_ERR_OR_NULL(info_linear)) { > @@ -153,8 +165,8 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, > machine, process); > } > > - /* Synthesize PERF_RECORD_BPF_EVENT */ > if (opts->bpf_event) { > + /* Synthesize PERF_RECORD_BPF_EVENT */ > *bpf_event = (struct bpf_event){ > .header = { > .type = PERF_RECORD_BPF_EVENT, > @@ -167,6 +179,24 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, > memcpy(bpf_event->tag, info->tag, BPF_TAG_SIZE); > memset((void *)event + event->header.size, 0, machine->id_hdr_size); > event->header.size += machine->id_hdr_size; > + > + /* save bpf_prog_info to env */ why do we save this to perf_env in here? we just synthesize the same data as event, so report and top will read it and fill perf_env again, right? could you please explain the whole flow of the bpf events and its respective data in perf_env and put it into the changelog > + info_node = malloc(sizeof(struct bpf_prog_info_node)); > + > + /* > + * Do not bail out for !info_node, as we still want to > + * call perf_tool__process_synth_event() well, we are out of memory, so I dont think perf_tool__process_synth_event will get too far.. also the perf_env data would be inconsistent with what you store as event.. how can that work? thanks, jirka > + */ > + if (info_node) { > + info_node->info_linear = info_linear; > + perf_env__insert_bpf_prog_info(env, info_node); > + info_linear = NULL; > + } > + SNIP
On Mon, Feb 25, 2019 at 04:20:10PM -0800, Song Liu wrote: SNIP > @@ -38,6 +116,12 @@ void perf_env__exit(struct perf_env *env) > zfree(&env->memory_nodes); > } > > +static void init_bpf_rb_trees(struct perf_env *env) > +{ > + env->bpf_progs.prog_infos = RB_ROOT; > + init_rwsem(&env->bpf_progs.lock); > +} > + > int perf_env__set_cmdline(struct perf_env *env, int argc, const char *argv[]) > { > int i; > @@ -59,6 +143,7 @@ int perf_env__set_cmdline(struct perf_env *env, int argc, const char *argv[]) > > env->nr_cmdline = argc; > > + init_bpf_rb_trees(env); this souldn't be in perf_env__set_cmdline, it's there to set the cmdline struct bpf_progs is first in perf_env that needs other than zero initialization, so I think we need to add perf_env__init function, that will do that for all the paths that uses perf_env jirka
On Mon, Feb 25, 2019 at 04:20:10PM -0800, Song Liu wrote: SNIP > diff --git a/tools/perf/util/env.h b/tools/perf/util/env.h > index d01b8355f4ca..33ef4b2d2a29 100644 > --- a/tools/perf/util/env.h > +++ b/tools/perf/util/env.h > @@ -3,7 +3,9 @@ > #define __PERF_ENV_H > > #include <linux/types.h> > +#include <linux/rbtree.h> > #include "cpumap.h" > +#include "rwsem.h" > > struct cpu_topology_map { > int socket_id; > @@ -64,8 +66,19 @@ struct perf_env { > struct memory_node *memory_nodes; > unsigned long long memory_bsize; > u64 clockid_res_ns; > + > + /* > + * bpf_info_lock protects bpf rbtrees. This is needed because the > + * trees are accessed by different threads in perf-top > + */ > + struct { > + struct rw_semaphore lock; > + struct rb_root prog_infos; could be just 'infos' ^^^^ is already in struct name > + } bpf_progs; > }; > jirka
> On Feb 27, 2019, at 5:21 AM, Jiri Olsa <jolsa@redhat.com> wrote: > > On Mon, Feb 25, 2019 at 04:20:10PM -0800, Song Liu wrote: >> bpf_prog_info contains information necessary to annotate bpf programs. >> This patch saves bpf_prog_info for bpf programs loaded in the system. >> >> Signed-off-by: Song Liu <songliubraving@fb.com> >> --- >> tools/perf/util/bpf-event.c | 32 +++++++++++++- >> tools/perf/util/bpf-event.h | 7 ++- >> tools/perf/util/env.c | 85 +++++++++++++++++++++++++++++++++++++ >> tools/perf/util/env.h | 17 ++++++++ >> 4 files changed, 139 insertions(+), 2 deletions(-) >> >> diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c >> index ff7ee149ec46..ce81b2c43a51 100644 >> --- a/tools/perf/util/bpf-event.c >> +++ b/tools/perf/util/bpf-event.c >> @@ -10,6 +10,7 @@ >> #include "debug.h" >> #include "symbol.h" >> #include "machine.h" >> +#include "env.h" >> #include "session.h" >> >> #define ptr_to_u64(ptr) ((__u64)(unsigned long)(ptr)) >> @@ -54,17 +55,28 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, >> struct bpf_event *bpf_event = &event->bpf_event; >> struct bpf_prog_info_linear *info_linear; >> struct perf_tool *tool = session->tool; >> + struct bpf_prog_info_node *info_node; >> struct bpf_prog_info *info; >> struct btf *btf = NULL; >> bool has_btf = false; >> + struct perf_env *env; >> u32 sub_prog_cnt, i; >> int err = 0; >> u64 arrays; >> >> + /* >> + * for perf-record and perf-report use header.env; >> + * otherwise, use global perf_env. >> + */ >> + env = session->data ? &session->header.env : &perf_env; >> + >> arrays = 1UL << BPF_PROG_INFO_JITED_KSYMS; >> arrays |= 1UL << BPF_PROG_INFO_JITED_FUNC_LENS; >> arrays |= 1UL << BPF_PROG_INFO_FUNC_INFO; >> arrays |= 1UL << BPF_PROG_INFO_PROG_TAGS; >> + arrays |= 1UL << BPF_PROG_INFO_JITED_INSNS; >> + arrays |= 1UL << BPF_PROG_INFO_LINE_INFO; >> + arrays |= 1UL << BPF_PROG_INFO_JITED_LINE_INFO; >> >> info_linear = bpf_program__get_prog_info_linear(fd, arrays); >> if (IS_ERR_OR_NULL(info_linear)) { >> @@ -153,8 +165,8 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, >> machine, process); >> } >> >> - /* Synthesize PERF_RECORD_BPF_EVENT */ >> if (opts->bpf_event) { >> + /* Synthesize PERF_RECORD_BPF_EVENT */ >> *bpf_event = (struct bpf_event){ >> .header = { >> .type = PERF_RECORD_BPF_EVENT, >> @@ -167,6 +179,24 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, >> memcpy(bpf_event->tag, info->tag, BPF_TAG_SIZE); >> memset((void *)event + event->header.size, 0, machine->id_hdr_size); >> event->header.size += machine->id_hdr_size; >> + >> + /* save bpf_prog_info to env */ > > why do we save this to perf_env in here? we just > synthesize the same data as event, so report and > top will read it and fill perf_env again, right? The synthesized events are same as PERF_RECORD_BPF_EVENT PROG_LOAD. We need to process them and fill perf_env as soon as we get PROG_LOAD. Otherwise, the program might unload before we process them. > > could you please explain the whole flow of the > bpf events and its respective data in perf_env > and put it into the changelog I will add more information to the change log. > >> + info_node = malloc(sizeof(struct bpf_prog_info_node)); >> + >> + /* >> + * Do not bail out for !info_node, as we still want to >> + * call perf_tool__process_synth_event() > > well, we are out of memory, so I dont think perf_tool__process_synth_event > will get too far.. also the perf_env data would be inconsistent with what > you store as event.. how can that work? It is OK we have PERF_RECORD_BPF_EVENT but not related bpf_prog_info and btf. The perf.data file will show a BPF program was loaded, but we won't be able to do annotation. Does this make sense? Thanks, Song > > thanks, > jirka > >> + */ >> + if (info_node) { >> + info_node->info_linear = info_linear; >> + perf_env__insert_bpf_prog_info(env, info_node); >> + info_linear = NULL; >> + } >> + > > SNIP
diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c index ff7ee149ec46..ce81b2c43a51 100644 --- a/tools/perf/util/bpf-event.c +++ b/tools/perf/util/bpf-event.c @@ -10,6 +10,7 @@ #include "debug.h" #include "symbol.h" #include "machine.h" +#include "env.h" #include "session.h" #define ptr_to_u64(ptr) ((__u64)(unsigned long)(ptr)) @@ -54,17 +55,28 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, struct bpf_event *bpf_event = &event->bpf_event; struct bpf_prog_info_linear *info_linear; struct perf_tool *tool = session->tool; + struct bpf_prog_info_node *info_node; struct bpf_prog_info *info; struct btf *btf = NULL; bool has_btf = false; + struct perf_env *env; u32 sub_prog_cnt, i; int err = 0; u64 arrays; + /* + * for perf-record and perf-report use header.env; + * otherwise, use global perf_env. + */ + env = session->data ? &session->header.env : &perf_env; + arrays = 1UL << BPF_PROG_INFO_JITED_KSYMS; arrays |= 1UL << BPF_PROG_INFO_JITED_FUNC_LENS; arrays |= 1UL << BPF_PROG_INFO_FUNC_INFO; arrays |= 1UL << BPF_PROG_INFO_PROG_TAGS; + arrays |= 1UL << BPF_PROG_INFO_JITED_INSNS; + arrays |= 1UL << BPF_PROG_INFO_LINE_INFO; + arrays |= 1UL << BPF_PROG_INFO_JITED_LINE_INFO; info_linear = bpf_program__get_prog_info_linear(fd, arrays); if (IS_ERR_OR_NULL(info_linear)) { @@ -153,8 +165,8 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, machine, process); } - /* Synthesize PERF_RECORD_BPF_EVENT */ if (opts->bpf_event) { + /* Synthesize PERF_RECORD_BPF_EVENT */ *bpf_event = (struct bpf_event){ .header = { .type = PERF_RECORD_BPF_EVENT, @@ -167,6 +179,24 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, memcpy(bpf_event->tag, info->tag, BPF_TAG_SIZE); memset((void *)event + event->header.size, 0, machine->id_hdr_size); event->header.size += machine->id_hdr_size; + + /* save bpf_prog_info to env */ + info_node = malloc(sizeof(struct bpf_prog_info_node)); + + /* + * Do not bail out for !info_node, as we still want to + * call perf_tool__process_synth_event() + */ + if (info_node) { + info_node->info_linear = info_linear; + perf_env__insert_bpf_prog_info(env, info_node); + info_linear = NULL; + } + + /* + * process after saving bpf_prog_info to env, so that + * required information is ready for look up + */ err = perf_tool__process_synth_event(tool, event, machine, process); } diff --git a/tools/perf/util/bpf-event.h b/tools/perf/util/bpf-event.h index 6698683612a7..fad932f7404f 100644 --- a/tools/perf/util/bpf-event.h +++ b/tools/perf/util/bpf-event.h @@ -3,14 +3,19 @@ #define __PERF_BPF_EVENT_H #include <linux/compiler.h> +#include <linux/rbtree.h> #include "event.h" struct machine; union perf_event; struct perf_sample; -struct perf_tool; struct record_opts; +struct bpf_prog_info_node { + struct bpf_prog_info_linear *info_linear; + struct rb_node rb_node; +}; + #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 4c23779e271a..650c14ad7e9b 100644 --- a/tools/perf/util/env.c +++ b/tools/perf/util/env.c @@ -3,15 +3,93 @@ #include "env.h" #include "sane_ctype.h" #include "util.h" +#include "bpf-event.h" #include <errno.h> #include <sys/utsname.h> +#include <bpf/libbpf.h> struct perf_env perf_env; +void perf_env__insert_bpf_prog_info(struct perf_env *env, + struct bpf_prog_info_node *info_node) +{ + __u32 prog_id = info_node->info_linear->info.id; + struct bpf_prog_info_node *node; + struct rb_node *parent = NULL; + struct rb_node **p; + + down_write(&env->bpf_progs.lock); + p = &env->bpf_progs.prog_infos.rb_node; + + while (*p != NULL) { + parent = *p; + node = rb_entry(parent, struct bpf_prog_info_node, rb_node); + if (prog_id < node->info_linear->info.id) { + p = &(*p)->rb_left; + } else if (prog_id > node->info_linear->info.id) { + p = &(*p)->rb_right; + } else { + pr_debug("duplicated bpf prog info %u\n", prog_id); + goto out; + } + } + + rb_link_node(&info_node->rb_node, parent, p); + rb_insert_color(&info_node->rb_node, &env->bpf_progs.prog_infos); +out: + up_write(&env->bpf_progs.lock); +} + +struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env, + __u32 prog_id) +{ + struct bpf_prog_info_node *node = NULL; + struct rb_node *n; + + down_read(&env->bpf_progs.lock); + n = env->bpf_progs.prog_infos.rb_node; + + while (n) { + node = rb_entry(n, struct bpf_prog_info_node, rb_node); + if (prog_id < node->info_linear->info.id) + n = n->rb_left; + else if (prog_id > node->info_linear->info.id) + n = n->rb_right; + else + break; + } + + up_read(&env->bpf_progs.lock); + return node; +} + +/* purge data in bpf_prog_infos tree */ +static void perf_env__purge_bpf(struct perf_env *env) +{ + struct rb_root *root; + struct rb_node *next; + + down_write(&env->bpf_progs.lock); + + root = &env->bpf_progs.prog_infos; + next = rb_first(root); + + while (next) { + struct bpf_prog_info_node *node; + + node = rb_entry(next, struct bpf_prog_info_node, rb_node); + next = rb_next(&node->rb_node); + rb_erase_init(&node->rb_node, root); + free(node); + } + up_write(&env->bpf_progs.lock); +} + void perf_env__exit(struct perf_env *env) { int i; + perf_env__purge_bpf(env); zfree(&env->hostname); zfree(&env->os_release); zfree(&env->version); @@ -38,6 +116,12 @@ void perf_env__exit(struct perf_env *env) zfree(&env->memory_nodes); } +static void init_bpf_rb_trees(struct perf_env *env) +{ + env->bpf_progs.prog_infos = RB_ROOT; + init_rwsem(&env->bpf_progs.lock); +} + int perf_env__set_cmdline(struct perf_env *env, int argc, const char *argv[]) { int i; @@ -59,6 +143,7 @@ int perf_env__set_cmdline(struct perf_env *env, int argc, const char *argv[]) env->nr_cmdline = argc; + init_bpf_rb_trees(env); return 0; out_free: zfree(&env->cmdline_argv); diff --git a/tools/perf/util/env.h b/tools/perf/util/env.h index d01b8355f4ca..33ef4b2d2a29 100644 --- a/tools/perf/util/env.h +++ b/tools/perf/util/env.h @@ -3,7 +3,9 @@ #define __PERF_ENV_H #include <linux/types.h> +#include <linux/rbtree.h> #include "cpumap.h" +#include "rwsem.h" struct cpu_topology_map { int socket_id; @@ -64,8 +66,19 @@ struct perf_env { struct memory_node *memory_nodes; unsigned long long memory_bsize; u64 clockid_res_ns; + + /* + * bpf_info_lock protects bpf rbtrees. This is needed because the + * trees are accessed by different threads in perf-top + */ + struct { + struct rw_semaphore lock; + struct rb_root prog_infos; + } bpf_progs; }; +struct bpf_prog_info_node; + extern struct perf_env perf_env; void perf_env__exit(struct perf_env *env); @@ -80,4 +93,8 @@ const char *perf_env__arch(struct perf_env *env); const char *perf_env__raw_arch(struct perf_env *env); int perf_env__nr_cpus_avail(struct perf_env *env); +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); #endif /* __PERF_ENV_H */
bpf_prog_info contains information necessary to annotate bpf programs. This patch saves bpf_prog_info for bpf programs loaded in the system. Signed-off-by: Song Liu <songliubraving@fb.com> --- tools/perf/util/bpf-event.c | 32 +++++++++++++- tools/perf/util/bpf-event.h | 7 ++- tools/perf/util/env.c | 85 +++++++++++++++++++++++++++++++++++++ tools/perf/util/env.h | 17 ++++++++ 4 files changed, 139 insertions(+), 2 deletions(-)