| Message ID | 20230608232823.4027869-3-irogers@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Fix memory leaks (was reference count checking for thread) | expand |
Em Thu, Jun 08, 2023 at 04:27:59PM -0700, Ian Rogers escreveu: > Separate the rbtree out of thread and into a new struct > thread_rb_node. The refcnt is in thread and the rbtree is responsible > for a single count. You stated what you did, but didn't spell out the reason, can you ellaborate on this so that the git history becomes more helpful for new contributors? - Arnaldo > Signed-off-by: Ian Rogers <irogers@google.com> > --- > tools/perf/builtin-report.c | 2 +- > tools/perf/builtin-trace.c | 2 +- > tools/perf/util/machine.c | 101 +++++++++++++++++++++++------------- > tools/perf/util/thread.c | 3 -- > tools/perf/util/thread.h | 6 ++- > 5 files changed, 73 insertions(+), 41 deletions(-) > > diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c > index 92c6797e7cba..c7d526283baf 100644 > --- a/tools/perf/builtin-report.c > +++ b/tools/perf/builtin-report.c > @@ -911,7 +911,7 @@ static int tasks_print(struct report *rep, FILE *fp) > nd = rb_next(nd)) { > task = tasks + itask++; > > - task->thread = rb_entry(nd, struct thread, rb_node); > + task->thread = rb_entry(nd, struct thread_rb_node, rb_node)->thread; > INIT_LIST_HEAD(&task->children); > INIT_LIST_HEAD(&task->list); > thread__set_priv(task->thread, task); > diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c > index 62c7c99a0fe4..b0dd202d14eb 100644 > --- a/tools/perf/builtin-trace.c > +++ b/tools/perf/builtin-trace.c > @@ -4348,7 +4348,7 @@ DEFINE_RESORT_RB(threads, (thread__nr_events(a->thread->priv) < thread__nr_event > struct thread *thread; > ) > { > - entry->thread = rb_entry(nd, struct thread, rb_node); > + entry->thread = rb_entry(nd, struct thread_rb_node, rb_node)->thread; > } > > static size_t trace__fprintf_thread_summary(struct trace *trace, FILE *fp) > diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c > index a1954ac85f59..cbf092e32ee9 100644 > --- a/tools/perf/util/machine.c > +++ b/tools/perf/util/machine.c > @@ -43,7 +43,8 @@ > #include <linux/string.h> > #include <linux/zalloc.h> > > -static void __machine__remove_thread(struct machine *machine, struct thread *th, bool lock); > +static void __machine__remove_thread(struct machine *machine, struct thread_rb_node *nd, > + struct thread *th, bool lock); > static int append_inlines(struct callchain_cursor *cursor, struct map_symbol *ms, u64 ip); > > static struct dso *machine__kernel_dso(struct machine *machine) > @@ -72,6 +73,21 @@ static void machine__threads_init(struct machine *machine) > } > } > > +static int thread_rb_node__cmp_tid(const void *key, const struct rb_node *nd) > +{ > + int to_find = (int) *((pid_t *)key); > + > + return to_find - (int)rb_entry(nd, struct thread_rb_node, rb_node)->thread->tid; > +} > + > +static struct thread_rb_node *thread_rb_node__find(const struct thread *th, > + struct rb_root *tree) > +{ > + struct rb_node *nd = rb_find(&th->tid, tree, thread_rb_node__cmp_tid); > + > + return rb_entry(nd, struct thread_rb_node, rb_node); > +} > + > static int machine__set_mmap_name(struct machine *machine) > { > if (machine__is_host(machine)) > @@ -214,10 +230,10 @@ void machine__delete_threads(struct machine *machine) > down_write(&threads->lock); > nd = rb_first_cached(&threads->entries); > while (nd) { > - struct thread *t = rb_entry(nd, struct thread, rb_node); > + struct thread_rb_node *trb = rb_entry(nd, struct thread_rb_node, rb_node); > > nd = rb_next(nd); > - __machine__remove_thread(machine, t, false); > + __machine__remove_thread(machine, trb, trb->thread, false); > } > up_write(&threads->lock); > } > @@ -605,6 +621,7 @@ static struct thread *____machine__findnew_thread(struct machine *machine, > struct rb_node **p = &threads->entries.rb_root.rb_node; > struct rb_node *parent = NULL; > struct thread *th; > + struct thread_rb_node *nd; > bool leftmost = true; > > th = threads__get_last_match(threads, machine, pid, tid); > @@ -613,7 +630,7 @@ static struct thread *____machine__findnew_thread(struct machine *machine, > > while (*p != NULL) { > parent = *p; > - th = rb_entry(parent, struct thread, rb_node); > + th = rb_entry(parent, struct thread_rb_node, rb_node)->thread; > > if (th->tid == tid) { > threads__set_last_match(threads, th); > @@ -633,30 +650,39 @@ static struct thread *____machine__findnew_thread(struct machine *machine, > return NULL; > > th = thread__new(pid, tid); > - if (th != NULL) { > - rb_link_node(&th->rb_node, parent, p); > - rb_insert_color_cached(&th->rb_node, &threads->entries, leftmost); > + if (th == NULL) > + return NULL; > > - /* > - * We have to initialize maps separately after rb tree is updated. > - * > - * The reason is that we call machine__findnew_thread > - * within thread__init_maps to find the thread > - * leader and that would screwed the rb tree. > - */ > - if (thread__init_maps(th, machine)) { > - rb_erase_cached(&th->rb_node, &threads->entries); > - RB_CLEAR_NODE(&th->rb_node); > - thread__put(th); > - return NULL; > - } > - /* > - * It is now in the rbtree, get a ref > - */ > - thread__get(th); > - threads__set_last_match(threads, th); > - ++threads->nr; > + nd = malloc(sizeof(*nd)); > + if (nd == NULL) { > + thread__put(th); > + return NULL; > + } > + nd->thread = th; > + > + rb_link_node(&nd->rb_node, parent, p); > + rb_insert_color_cached(&nd->rb_node, &threads->entries, leftmost); > + > + /* > + * We have to initialize maps separately after rb tree is updated. > + * > + * The reason is that we call machine__findnew_thread within > + * thread__init_maps to find the thread leader and that would screwed > + * the rb tree. > + */ > + if (thread__init_maps(th, machine)) { > + rb_erase_cached(&nd->rb_node, &threads->entries); > + RB_CLEAR_NODE(&nd->rb_node); > + free(nd); > + thread__put(th); > + return NULL; > } > + /* > + * It is now in the rbtree, get a ref > + */ > + thread__get(th); > + threads__set_last_match(threads, th); > + ++threads->nr; > > return th; > } > @@ -1109,7 +1135,7 @@ size_t machine__fprintf(struct machine *machine, FILE *fp) > > for (nd = rb_first_cached(&threads->entries); nd; > nd = rb_next(nd)) { > - struct thread *pos = rb_entry(nd, struct thread, rb_node); > + struct thread *pos = rb_entry(nd, struct thread_rb_node, rb_node)->thread; > > ret += thread__fprintf(pos, fp); > } > @@ -2020,10 +2046,14 @@ int machine__process_mmap_event(struct machine *machine, union perf_event *event > return 0; > } > > -static void __machine__remove_thread(struct machine *machine, struct thread *th, bool lock) > +static void __machine__remove_thread(struct machine *machine, struct thread_rb_node *nd, > + struct thread *th, bool lock) > { > struct threads *threads = machine__threads(machine, th->tid); > > + if (!nd) > + nd = thread_rb_node__find(th, &threads->entries.rb_root); > + > if (threads->last_match == th) > threads__set_last_match(threads, NULL); > > @@ -2032,11 +2062,12 @@ static void __machine__remove_thread(struct machine *machine, struct thread *th, > > BUG_ON(refcount_read(&th->refcnt) == 0); > > - rb_erase_cached(&th->rb_node, &threads->entries); > - RB_CLEAR_NODE(&th->rb_node); > + thread__put(nd->thread); > + rb_erase_cached(&nd->rb_node, &threads->entries); > + RB_CLEAR_NODE(&nd->rb_node); > --threads->nr; > > - thread__put(th); > + free(nd); > > if (lock) > up_write(&threads->lock); > @@ -2044,7 +2075,7 @@ static void __machine__remove_thread(struct machine *machine, struct thread *th, > > void machine__remove_thread(struct machine *machine, struct thread *th) > { > - return __machine__remove_thread(machine, th, true); > + return __machine__remove_thread(machine, NULL, th, true); > } > > int machine__process_fork_event(struct machine *machine, union perf_event *event, > @@ -3167,7 +3198,6 @@ int machine__for_each_thread(struct machine *machine, > { > struct threads *threads; > struct rb_node *nd; > - struct thread *thread; > int rc = 0; > int i; > > @@ -3175,8 +3205,9 @@ int machine__for_each_thread(struct machine *machine, > threads = &machine->threads[i]; > for (nd = rb_first_cached(&threads->entries); nd; > nd = rb_next(nd)) { > - thread = rb_entry(nd, struct thread, rb_node); > - rc = fn(thread, priv); > + struct thread_rb_node *trb = rb_entry(nd, struct thread_rb_node, rb_node); > + > + rc = fn(trb->thread, priv); > if (rc != 0) > return rc; > } > diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c > index d949bffc0ed6..38d300e3e4d3 100644 > --- a/tools/perf/util/thread.c > +++ b/tools/perf/util/thread.c > @@ -66,7 +66,6 @@ struct thread *thread__new(pid_t pid, pid_t tid) > > list_add(&comm->list, &thread->comm_list); > refcount_set(&thread->refcnt, 1); > - RB_CLEAR_NODE(&thread->rb_node); > /* Thread holds first ref to nsdata. */ > thread->nsinfo = nsinfo__new(pid); > srccode_state_init(&thread->srccode_state); > @@ -84,8 +83,6 @@ void thread__delete(struct thread *thread) > struct namespaces *namespaces, *tmp_namespaces; > struct comm *comm, *tmp_comm; > > - BUG_ON(!RB_EMPTY_NODE(&thread->rb_node)); > - > thread_stack__free(thread); > > if (thread->maps) { > diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h > index 86737812e06b..3b3f9fb5a916 100644 > --- a/tools/perf/util/thread.h > +++ b/tools/perf/util/thread.h > @@ -29,8 +29,12 @@ struct lbr_stitch { > struct callchain_cursor_node *prev_lbr_cursor; > }; > > +struct thread_rb_node { > + struct rb_node rb_node; > + struct thread *thread; > +}; > + > struct thread { > - struct rb_node rb_node; > struct maps *maps; > pid_t pid_; /* Not all tools update this */ > pid_t tid; > -- > 2.41.0.162.gfafddb0af9-goog >
diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c index 92c6797e7cba..c7d526283baf 100644 --- a/tools/perf/builtin-report.c +++ b/tools/perf/builtin-report.c @@ -911,7 +911,7 @@ static int tasks_print(struct report *rep, FILE *fp) nd = rb_next(nd)) { task = tasks + itask++; - task->thread = rb_entry(nd, struct thread, rb_node); + task->thread = rb_entry(nd, struct thread_rb_node, rb_node)->thread; INIT_LIST_HEAD(&task->children); INIT_LIST_HEAD(&task->list); thread__set_priv(task->thread, task); diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 62c7c99a0fe4..b0dd202d14eb 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -4348,7 +4348,7 @@ DEFINE_RESORT_RB(threads, (thread__nr_events(a->thread->priv) < thread__nr_event struct thread *thread; ) { - entry->thread = rb_entry(nd, struct thread, rb_node); + entry->thread = rb_entry(nd, struct thread_rb_node, rb_node)->thread; } static size_t trace__fprintf_thread_summary(struct trace *trace, FILE *fp) diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index a1954ac85f59..cbf092e32ee9 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -43,7 +43,8 @@ #include <linux/string.h> #include <linux/zalloc.h> -static void __machine__remove_thread(struct machine *machine, struct thread *th, bool lock); +static void __machine__remove_thread(struct machine *machine, struct thread_rb_node *nd, + struct thread *th, bool lock); static int append_inlines(struct callchain_cursor *cursor, struct map_symbol *ms, u64 ip); static struct dso *machine__kernel_dso(struct machine *machine) @@ -72,6 +73,21 @@ static void machine__threads_init(struct machine *machine) } } +static int thread_rb_node__cmp_tid(const void *key, const struct rb_node *nd) +{ + int to_find = (int) *((pid_t *)key); + + return to_find - (int)rb_entry(nd, struct thread_rb_node, rb_node)->thread->tid; +} + +static struct thread_rb_node *thread_rb_node__find(const struct thread *th, + struct rb_root *tree) +{ + struct rb_node *nd = rb_find(&th->tid, tree, thread_rb_node__cmp_tid); + + return rb_entry(nd, struct thread_rb_node, rb_node); +} + static int machine__set_mmap_name(struct machine *machine) { if (machine__is_host(machine)) @@ -214,10 +230,10 @@ void machine__delete_threads(struct machine *machine) down_write(&threads->lock); nd = rb_first_cached(&threads->entries); while (nd) { - struct thread *t = rb_entry(nd, struct thread, rb_node); + struct thread_rb_node *trb = rb_entry(nd, struct thread_rb_node, rb_node); nd = rb_next(nd); - __machine__remove_thread(machine, t, false); + __machine__remove_thread(machine, trb, trb->thread, false); } up_write(&threads->lock); } @@ -605,6 +621,7 @@ static struct thread *____machine__findnew_thread(struct machine *machine, struct rb_node **p = &threads->entries.rb_root.rb_node; struct rb_node *parent = NULL; struct thread *th; + struct thread_rb_node *nd; bool leftmost = true; th = threads__get_last_match(threads, machine, pid, tid); @@ -613,7 +630,7 @@ static struct thread *____machine__findnew_thread(struct machine *machine, while (*p != NULL) { parent = *p; - th = rb_entry(parent, struct thread, rb_node); + th = rb_entry(parent, struct thread_rb_node, rb_node)->thread; if (th->tid == tid) { threads__set_last_match(threads, th); @@ -633,30 +650,39 @@ static struct thread *____machine__findnew_thread(struct machine *machine, return NULL; th = thread__new(pid, tid); - if (th != NULL) { - rb_link_node(&th->rb_node, parent, p); - rb_insert_color_cached(&th->rb_node, &threads->entries, leftmost); + if (th == NULL) + return NULL; - /* - * We have to initialize maps separately after rb tree is updated. - * - * The reason is that we call machine__findnew_thread - * within thread__init_maps to find the thread - * leader and that would screwed the rb tree. - */ - if (thread__init_maps(th, machine)) { - rb_erase_cached(&th->rb_node, &threads->entries); - RB_CLEAR_NODE(&th->rb_node); - thread__put(th); - return NULL; - } - /* - * It is now in the rbtree, get a ref - */ - thread__get(th); - threads__set_last_match(threads, th); - ++threads->nr; + nd = malloc(sizeof(*nd)); + if (nd == NULL) { + thread__put(th); + return NULL; + } + nd->thread = th; + + rb_link_node(&nd->rb_node, parent, p); + rb_insert_color_cached(&nd->rb_node, &threads->entries, leftmost); + + /* + * We have to initialize maps separately after rb tree is updated. + * + * The reason is that we call machine__findnew_thread within + * thread__init_maps to find the thread leader and that would screwed + * the rb tree. + */ + if (thread__init_maps(th, machine)) { + rb_erase_cached(&nd->rb_node, &threads->entries); + RB_CLEAR_NODE(&nd->rb_node); + free(nd); + thread__put(th); + return NULL; } + /* + * It is now in the rbtree, get a ref + */ + thread__get(th); + threads__set_last_match(threads, th); + ++threads->nr; return th; } @@ -1109,7 +1135,7 @@ size_t machine__fprintf(struct machine *machine, FILE *fp) for (nd = rb_first_cached(&threads->entries); nd; nd = rb_next(nd)) { - struct thread *pos = rb_entry(nd, struct thread, rb_node); + struct thread *pos = rb_entry(nd, struct thread_rb_node, rb_node)->thread; ret += thread__fprintf(pos, fp); } @@ -2020,10 +2046,14 @@ int machine__process_mmap_event(struct machine *machine, union perf_event *event return 0; } -static void __machine__remove_thread(struct machine *machine, struct thread *th, bool lock) +static void __machine__remove_thread(struct machine *machine, struct thread_rb_node *nd, + struct thread *th, bool lock) { struct threads *threads = machine__threads(machine, th->tid); + if (!nd) + nd = thread_rb_node__find(th, &threads->entries.rb_root); + if (threads->last_match == th) threads__set_last_match(threads, NULL); @@ -2032,11 +2062,12 @@ static void __machine__remove_thread(struct machine *machine, struct thread *th, BUG_ON(refcount_read(&th->refcnt) == 0); - rb_erase_cached(&th->rb_node, &threads->entries); - RB_CLEAR_NODE(&th->rb_node); + thread__put(nd->thread); + rb_erase_cached(&nd->rb_node, &threads->entries); + RB_CLEAR_NODE(&nd->rb_node); --threads->nr; - thread__put(th); + free(nd); if (lock) up_write(&threads->lock); @@ -2044,7 +2075,7 @@ static void __machine__remove_thread(struct machine *machine, struct thread *th, void machine__remove_thread(struct machine *machine, struct thread *th) { - return __machine__remove_thread(machine, th, true); + return __machine__remove_thread(machine, NULL, th, true); } int machine__process_fork_event(struct machine *machine, union perf_event *event, @@ -3167,7 +3198,6 @@ int machine__for_each_thread(struct machine *machine, { struct threads *threads; struct rb_node *nd; - struct thread *thread; int rc = 0; int i; @@ -3175,8 +3205,9 @@ int machine__for_each_thread(struct machine *machine, threads = &machine->threads[i]; for (nd = rb_first_cached(&threads->entries); nd; nd = rb_next(nd)) { - thread = rb_entry(nd, struct thread, rb_node); - rc = fn(thread, priv); + struct thread_rb_node *trb = rb_entry(nd, struct thread_rb_node, rb_node); + + rc = fn(trb->thread, priv); if (rc != 0) return rc; } diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c index d949bffc0ed6..38d300e3e4d3 100644 --- a/tools/perf/util/thread.c +++ b/tools/perf/util/thread.c @@ -66,7 +66,6 @@ struct thread *thread__new(pid_t pid, pid_t tid) list_add(&comm->list, &thread->comm_list); refcount_set(&thread->refcnt, 1); - RB_CLEAR_NODE(&thread->rb_node); /* Thread holds first ref to nsdata. */ thread->nsinfo = nsinfo__new(pid); srccode_state_init(&thread->srccode_state); @@ -84,8 +83,6 @@ void thread__delete(struct thread *thread) struct namespaces *namespaces, *tmp_namespaces; struct comm *comm, *tmp_comm; - BUG_ON(!RB_EMPTY_NODE(&thread->rb_node)); - thread_stack__free(thread); if (thread->maps) { diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h index 86737812e06b..3b3f9fb5a916 100644 --- a/tools/perf/util/thread.h +++ b/tools/perf/util/thread.h @@ -29,8 +29,12 @@ struct lbr_stitch { struct callchain_cursor_node *prev_lbr_cursor; }; +struct thread_rb_node { + struct rb_node rb_node; + struct thread *thread; +}; + struct thread { - struct rb_node rb_node; struct maps *maps; pid_t pid_; /* Not all tools update this */ pid_t tid;
Separate the rbtree out of thread and into a new struct thread_rb_node. The refcnt is in thread and the rbtree is responsible for a single count. Signed-off-by: Ian Rogers <irogers@google.com> --- tools/perf/builtin-report.c | 2 +- tools/perf/builtin-trace.c | 2 +- tools/perf/util/machine.c | 101 +++++++++++++++++++++++------------- tools/perf/util/thread.c | 3 -- tools/perf/util/thread.h | 6 ++- 5 files changed, 73 insertions(+), 41 deletions(-)