5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Ian Rogers irogers@google.com
[ Upstream commit 9c51f8788b5d4e9f46afbcf563255cfd355690b3 ]
Add variants of perf_env__insert_bpf_prog_info(), perf_env__insert_btf() and perf_env__find_btf prefixed with __ to indicate the env->bpf_progs.lock is assumed held.
Call these variants when the lock is held to avoid recursively taking it and potentially having a thread deadlock with itself.
Fixes: f8dfeae009effc0b ("perf bpf: Show more BPF program info in print_bpf_prog_info()") Signed-off-by: Ian Rogers irogers@google.com Acked-by: Jiri Olsa jolsa@kernel.org Acked-by: Song Liu song@kernel.org Cc: Adrian Hunter adrian.hunter@intel.com Cc: Alexander Shishkin alexander.shishkin@linux.intel.com Cc: Huacai Chen chenhuacai@kernel.org Cc: Ingo Molnar mingo@redhat.com Cc: K Prateek Nayak kprateek.nayak@amd.com Cc: Kan Liang kan.liang@linux.intel.com Cc: Mark Rutland mark.rutland@arm.com Cc: Ming Wang wangming01@loongson.cn Cc: Namhyung Kim namhyung@kernel.org Cc: Peter Zijlstra peterz@infradead.org Cc: Ravi Bangoria ravi.bangoria@amd.com Link: https://lore.kernel.org/r/20231207014655.1252484-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- tools/perf/util/bpf-event.c | 8 +++--- tools/perf/util/bpf-event.h | 12 ++++----- tools/perf/util/env.c | 50 ++++++++++++++++++++++++------------- tools/perf/util/env.h | 4 +++ tools/perf/util/header.c | 8 +++--- 5 files changed, 50 insertions(+), 32 deletions(-)
diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c index 96e0a31a38f6..ae30e20af246 100644 --- a/tools/perf/util/bpf-event.c +++ b/tools/perf/util/bpf-event.c @@ -442,9 +442,9 @@ int evlist__add_bpf_sb_event(struct evlist *evlist, struct perf_env *env) return perf_evlist__add_sb_event(evlist, &attr, bpf_event__sb_cb, env); }
-void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info, - struct perf_env *env, - FILE *fp) +void __bpf_event__print_bpf_prog_info(struct bpf_prog_info *info, + struct perf_env *env, + FILE *fp) { __u32 *prog_lens = (__u32 *)(uintptr_t)(info->jited_func_lens); __u64 *prog_addrs = (__u64 *)(uintptr_t)(info->jited_ksyms); @@ -460,7 +460,7 @@ void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info, if (info->btf_id) { struct btf_node *node;
- node = perf_env__find_btf(env, info->btf_id); + node = __perf_env__find_btf(env, info->btf_id); if (node) btf = btf__new((__u8 *)(node->data), node->data_size); diff --git a/tools/perf/util/bpf-event.h b/tools/perf/util/bpf-event.h index 68f315c3df5b..50f7412464df 100644 --- a/tools/perf/util/bpf-event.h +++ b/tools/perf/util/bpf-event.h @@ -34,9 +34,9 @@ struct btf_node { int machine__process_bpf(struct machine *machine, union perf_event *event, struct perf_sample *sample); int evlist__add_bpf_sb_event(struct evlist *evlist, struct perf_env *env); -void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info, - struct perf_env *env, - FILE *fp); +void __bpf_event__print_bpf_prog_info(struct bpf_prog_info *info, + struct perf_env *env, + FILE *fp); #else static inline int machine__process_bpf(struct machine *machine __maybe_unused, union perf_event *event __maybe_unused, @@ -51,9 +51,9 @@ static inline int evlist__add_bpf_sb_event(struct evlist *evlist __maybe_unused, return 0; }
-static inline void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info __maybe_unused, - struct perf_env *env __maybe_unused, - FILE *fp __maybe_unused) +static inline void __bpf_event__print_bpf_prog_info(struct bpf_prog_info *info __maybe_unused, + struct perf_env *env __maybe_unused, + FILE *fp __maybe_unused) {
} diff --git a/tools/perf/util/env.c b/tools/perf/util/env.c index 2d517f377053..953db9dd25eb 100644 --- a/tools/perf/util/env.c +++ b/tools/perf/util/env.c @@ -15,13 +15,19 @@ struct perf_env perf_env;
void perf_env__insert_bpf_prog_info(struct perf_env *env, struct bpf_prog_info_node *info_node) +{ + down_write(&env->bpf_progs.lock); + __perf_env__insert_bpf_prog_info(env, info_node); + up_write(&env->bpf_progs.lock); +} + +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.infos.rb_node;
while (*p != NULL) { @@ -33,15 +39,13 @@ void perf_env__insert_bpf_prog_info(struct perf_env *env, p = &(*p)->rb_right; } else { pr_debug("duplicated bpf prog info %u\n", prog_id); - goto out; + return; } }
rb_link_node(&info_node->rb_node, parent, p); rb_insert_color(&info_node->rb_node, &env->bpf_progs.infos); env->bpf_progs.infos_cnt++; -out: - up_write(&env->bpf_progs.lock); }
struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env, @@ -70,14 +74,22 @@ struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env, }
bool perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node) +{ + bool ret; + + down_write(&env->bpf_progs.lock); + ret = __perf_env__insert_btf(env, btf_node); + up_write(&env->bpf_progs.lock); + return ret; +} + +bool __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; - bool ret = true;
- down_write(&env->bpf_progs.lock); p = &env->bpf_progs.btfs.rb_node;
while (*p != NULL) { @@ -89,25 +101,31 @@ bool perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node) p = &(*p)->rb_right; } else { pr_debug("duplicated btf %u\n", btf_id); - ret = false; - goto out; + return false; } }
rb_link_node(&btf_node->rb_node, parent, p); rb_insert_color(&btf_node->rb_node, &env->bpf_progs.btfs); env->bpf_progs.btfs_cnt++; -out: - up_write(&env->bpf_progs.lock); - return ret; + return true; }
struct btf_node *perf_env__find_btf(struct perf_env *env, __u32 btf_id) +{ + struct btf_node *res; + + down_read(&env->bpf_progs.lock); + res = __perf_env__find_btf(env, btf_id); + up_read(&env->bpf_progs.lock); + return res; +} + +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) { @@ -117,13 +135,9 @@ struct btf_node *perf_env__find_btf(struct perf_env *env, __u32 btf_id) else if (btf_id > node->id) n = n->rb_right; else - goto out; + return node; } - node = NULL; - -out: - up_read(&env->bpf_progs.lock); - return node; + return NULL; }
/* purge data in bpf_progs.infos tree */ diff --git a/tools/perf/util/env.h b/tools/perf/util/env.h index ceddddace5cc..b0778483fa04 100644 --- a/tools/perf/util/env.h +++ b/tools/perf/util/env.h @@ -117,12 +117,16 @@ const char *perf_env__raw_arch(struct perf_env *env); int perf_env__nr_cpus_avail(struct perf_env *env);
void perf_env__init(struct perf_env *env); +void __perf_env__insert_bpf_prog_info(struct perf_env *env, + struct bpf_prog_info_node *info_node); 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); bool perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node); +bool __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); +struct btf_node *__perf_env__find_btf(struct perf_env *env, __u32 btf_id);
int perf_env__numa_node(struct perf_env *env, int cpu); #endif /* __PERF_ENV_H */ diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c index 642528613927..a68feeb3eb00 100644 --- a/tools/perf/util/header.c +++ b/tools/perf/util/header.c @@ -1546,8 +1546,8 @@ static void print_bpf_prog_info(struct feat_fd *ff, FILE *fp) node = rb_entry(next, struct bpf_prog_info_node, rb_node); next = rb_next(&node->rb_node);
- bpf_event__print_bpf_prog_info(&node->info_linear->info, - env, fp); + __bpf_event__print_bpf_prog_info(&node->info_linear->info, + env, fp); }
up_read(&env->bpf_progs.lock); @@ -2724,7 +2724,7 @@ static int process_bpf_prog_info(struct feat_fd *ff, void *data __maybe_unused) /* after reading from file, translate offset to address */ bpf_program__bpil_offs_to_addr(info_linear); info_node->info_linear = info_linear; - perf_env__insert_bpf_prog_info(env, info_node); + __perf_env__insert_bpf_prog_info(env, info_node); }
up_write(&env->bpf_progs.lock); @@ -2777,7 +2777,7 @@ static int process_bpf_btf(struct feat_fd *ff, void *data __maybe_unused) if (__do_read(ff, node->data, data_size)) goto out;
- perf_env__insert_btf(env, node); + __perf_env__insert_btf(env, node); node = NULL; }