Move threads out of machine and move thread_rb_node into the C file. This hides the implementation of threads from the rest of the code allowing for it to be refactored. Locking discipline is tightened up in this change. Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx> --- tools/perf/util/Build | 1 + tools/perf/util/bpf_lock_contention.c | 8 +- tools/perf/util/machine.c | 287 ++++---------------------- tools/perf/util/machine.h | 20 +- tools/perf/util/thread.c | 2 +- tools/perf/util/thread.h | 6 - tools/perf/util/threads.c | 244 ++++++++++++++++++++++ tools/perf/util/threads.h | 35 ++++ 8 files changed, 325 insertions(+), 278 deletions(-) create mode 100644 tools/perf/util/threads.c create mode 100644 tools/perf/util/threads.h diff --git a/tools/perf/util/Build b/tools/perf/util/Build index 8027f450fa3e..a0e8cd68d490 100644 --- a/tools/perf/util/Build +++ b/tools/perf/util/Build @@ -71,6 +71,7 @@ perf-y += ordered-events.o perf-y += namespaces.o perf-y += comm.o perf-y += thread.o +perf-y += threads.o perf-y += thread_map.o perf-y += parse-events-flex.o perf-y += parse-events-bison.o diff --git a/tools/perf/util/bpf_lock_contention.c b/tools/perf/util/bpf_lock_contention.c index 31ff19afc20c..3992c8a9fd96 100644 --- a/tools/perf/util/bpf_lock_contention.c +++ b/tools/perf/util/bpf_lock_contention.c @@ -210,7 +210,7 @@ static const char *lock_contention_get_name(struct lock_contention *con, /* do not update idle comm which contains CPU number */ if (pid) { - struct thread *t = __machine__findnew_thread(machine, /*pid=*/-1, pid); + struct thread *t = machine__findnew_thread(machine, /*pid=*/-1, pid); if (t == NULL) return name; @@ -302,9 +302,9 @@ int lock_contention_read(struct lock_contention *con) return -1; if (con->aggr_mode == LOCK_AGGR_TASK) { - struct thread *idle = __machine__findnew_thread(machine, - /*pid=*/0, - /*tid=*/0); + struct thread *idle = machine__findnew_thread(machine, + /*pid=*/0, + /*tid=*/0); thread__set_comm(idle, "swapper", /*timestamp=*/0); } diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index e072b2115b64..e668a97255f8 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -43,9 +43,6 @@ #include <linux/string.h> #include <linux/zalloc.h> -static void __machine__remove_thread(struct machine *machine, struct thread_rb_node *nd, - struct thread *th, bool lock); - static struct dso *machine__kernel_dso(struct machine *machine) { return map__dso(machine->vmlinux_map); @@ -58,35 +55,6 @@ static void dsos__init(struct dsos *dsos) init_rwsem(&dsos->lock); } -static void machine__threads_init(struct machine *machine) -{ - int i; - - for (i = 0; i < THREADS__TABLE_SIZE; i++) { - struct threads *threads = &machine->threads[i]; - threads->entries = RB_ROOT_CACHED; - init_rwsem(&threads->lock); - threads->nr = 0; - threads->last_match = NULL; - } -} - -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)thread__tid(rb_entry(nd, struct thread_rb_node, rb_node)->thread); -} - -static struct thread_rb_node *thread_rb_node__find(const struct thread *th, - struct rb_root *tree) -{ - pid_t to_find = thread__tid(th); - struct rb_node *nd = rb_find(&to_find, 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)) @@ -120,7 +88,7 @@ int machine__init(struct machine *machine, const char *root_dir, pid_t pid) RB_CLEAR_NODE(&machine->rb_node); dsos__init(&machine->dsos); - machine__threads_init(machine); + threads__init(&machine->threads); machine->vdso_info = NULL; machine->env = NULL; @@ -221,27 +189,11 @@ static void dsos__exit(struct dsos *dsos) void machine__delete_threads(struct machine *machine) { - struct rb_node *nd; - int i; - - for (i = 0; i < THREADS__TABLE_SIZE; i++) { - struct threads *threads = &machine->threads[i]; - down_write(&threads->lock); - nd = rb_first_cached(&threads->entries); - while (nd) { - struct thread_rb_node *trb = rb_entry(nd, struct thread_rb_node, rb_node); - - nd = rb_next(nd); - __machine__remove_thread(machine, trb, trb->thread, false); - } - up_write(&threads->lock); - } + threads__remove_all_threads(&machine->threads); } void machine__exit(struct machine *machine) { - int i; - if (machine == NULL) return; @@ -254,12 +206,7 @@ void machine__exit(struct machine *machine) zfree(&machine->current_tid); zfree(&machine->kallsyms_filename); - machine__delete_threads(machine); - for (i = 0; i < THREADS__TABLE_SIZE; i++) { - struct threads *threads = &machine->threads[i]; - - exit_rwsem(&threads->lock); - } + threads__exit(&machine->threads); } void machine__delete(struct machine *machine) @@ -526,7 +473,7 @@ static void machine__update_thread_pid(struct machine *machine, if (thread__pid(th) == thread__tid(th)) return; - leader = __machine__findnew_thread(machine, thread__pid(th), thread__pid(th)); + leader = machine__findnew_thread(machine, thread__pid(th), thread__pid(th)); if (!leader) goto out_err; @@ -560,160 +507,55 @@ static void machine__update_thread_pid(struct machine *machine, goto out_put; } -/* - * Front-end cache - TID lookups come in blocks, - * so most of the time we dont have to look up - * the full rbtree: - */ -static struct thread* -__threads__get_last_match(struct threads *threads, struct machine *machine, - int pid, int tid) -{ - struct thread *th; - - th = threads->last_match; - if (th != NULL) { - if (thread__tid(th) == tid) { - machine__update_thread_pid(machine, th, pid); - return thread__get(th); - } - thread__put(threads->last_match); - threads->last_match = NULL; - } - - return NULL; -} - -static struct thread* -threads__get_last_match(struct threads *threads, struct machine *machine, - int pid, int tid) -{ - struct thread *th = NULL; - - if (perf_singlethreaded) - th = __threads__get_last_match(threads, machine, pid, tid); - - return th; -} - -static void -__threads__set_last_match(struct threads *threads, struct thread *th) -{ - thread__put(threads->last_match); - threads->last_match = thread__get(th); -} - -static void -threads__set_last_match(struct threads *threads, struct thread *th) -{ - if (perf_singlethreaded) - __threads__set_last_match(threads, th); -} - /* * Caller must eventually drop thread->refcnt returned with a successful * lookup/new thread inserted. */ -static struct thread *____machine__findnew_thread(struct machine *machine, - struct threads *threads, - pid_t pid, pid_t tid, - bool create) +static struct thread *__machine__findnew_thread(struct machine *machine, + pid_t pid, + pid_t tid, + bool create) { - 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; + struct thread *th = threads__find(&machine->threads, tid); + bool created; - th = threads__get_last_match(threads, machine, pid, tid); - if (th) + if (th) { + machine__update_thread_pid(machine, th, pid); return th; - - while (*p != NULL) { - parent = *p; - th = rb_entry(parent, struct thread_rb_node, rb_node)->thread; - - if (thread__tid(th) == tid) { - threads__set_last_match(threads, th); - machine__update_thread_pid(machine, th, pid); - return thread__get(th); - } - - if (tid < thread__tid(th)) - p = &(*p)->rb_left; - else { - p = &(*p)->rb_right; - leftmost = false; - } } - if (!create) return NULL; - th = thread__new(pid, tid); - if (th == NULL) - return NULL; - - 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)) { - pr_err("Thread init failed thread %d\n", pid); - 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 - */ - threads__set_last_match(threads, th); - ++threads->nr; - - return thread__get(th); -} + th = threads__findnew(&machine->threads, pid, tid, &created); + if (created) { + /* + * 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)) { + pr_err("Thread init failed thread %d\n", pid); + threads__remove(&machine->threads, th); + thread__put(th); + return NULL; + } + } else + machine__update_thread_pid(machine, th, pid); -struct thread *__machine__findnew_thread(struct machine *machine, pid_t pid, pid_t tid) -{ - return ____machine__findnew_thread(machine, machine__threads(machine, tid), pid, tid, true); + return th; } -struct thread *machine__findnew_thread(struct machine *machine, pid_t pid, - pid_t tid) +struct thread *machine__findnew_thread(struct machine *machine, pid_t pid, pid_t tid) { - struct threads *threads = machine__threads(machine, tid); - struct thread *th; - - down_write(&threads->lock); - th = __machine__findnew_thread(machine, pid, tid); - up_write(&threads->lock); - return th; + return __machine__findnew_thread(machine, pid, tid, /*create=*/true); } -struct thread *machine__find_thread(struct machine *machine, pid_t pid, - pid_t tid) +struct thread *machine__find_thread(struct machine *machine, pid_t pid, pid_t tid) { - struct threads *threads = machine__threads(machine, tid); - struct thread *th; - - down_read(&threads->lock); - th = ____machine__findnew_thread(machine, threads, pid, tid, false); - up_read(&threads->lock); - return th; + return __machine__findnew_thread(machine, pid, tid, /*create=*/false); } /* @@ -1127,23 +969,13 @@ static int machine_fprintf_cb(struct thread *thread, void *data) return 0; } -static size_t machine__threads_nr(const struct machine *machine) -{ - size_t nr = 0; - - for (int i = 0; i < THREADS__TABLE_SIZE; i++) - nr += machine->threads[i].nr; - - return nr; -} - size_t machine__fprintf(struct machine *machine, FILE *fp) { struct machine_fprintf_cb_args args = { .fp = fp, .printed = 0, }; - size_t ret = fprintf(fp, "Threads: %zu\n", machine__threads_nr(machine)); + size_t ret = fprintf(fp, "Threads: %zu\n", threads__nr(&machine->threads)); machine__for_each_thread(machine, machine_fprintf_cb, &args); return ret + args.printed; @@ -2069,36 +1901,9 @@ int machine__process_mmap_event(struct machine *machine, union perf_event *event return 0; } -static void __machine__remove_thread(struct machine *machine, struct thread_rb_node *nd, - struct thread *th, bool lock) -{ - struct threads *threads = machine__threads(machine, thread__tid(th)); - - if (!nd) - nd = thread_rb_node__find(th, &threads->entries.rb_root); - - if (threads->last_match && RC_CHK_EQUAL(threads->last_match, th)) - threads__set_last_match(threads, NULL); - - if (lock) - down_write(&threads->lock); - - BUG_ON(refcount_read(thread__refcnt(th)) == 0); - - thread__put(nd->thread); - rb_erase_cached(&nd->rb_node, &threads->entries); - RB_CLEAR_NODE(&nd->rb_node); - --threads->nr; - - free(nd); - - if (lock) - up_write(&threads->lock); -} - void machine__remove_thread(struct machine *machine, struct thread *th) { - return __machine__remove_thread(machine, NULL, th, true); + return threads__remove(&machine->threads, th); } int machine__process_fork_event(struct machine *machine, union perf_event *event, @@ -3232,23 +3037,7 @@ int machine__for_each_thread(struct machine *machine, int (*fn)(struct thread *thread, void *p), void *priv) { - struct threads *threads; - struct rb_node *nd; - int rc = 0; - int i; - - for (i = 0; i < THREADS__TABLE_SIZE; i++) { - threads = &machine->threads[i]; - for (nd = rb_first_cached(&threads->entries); nd; - nd = rb_next(nd)) { - struct thread_rb_node *trb = rb_entry(nd, struct thread_rb_node, rb_node); - - rc = fn(trb->thread, priv); - if (rc != 0) - return rc; - } - } - return rc; + return threads__for_each_thread(&machine->threads, fn, priv); } int machines__for_each_thread(struct machines *machines, diff --git a/tools/perf/util/machine.h b/tools/perf/util/machine.h index b738ce84817b..e28c787616fe 100644 --- a/tools/perf/util/machine.h +++ b/tools/perf/util/machine.h @@ -7,6 +7,7 @@ #include "maps.h" #include "dsos.h" #include "rwsem.h" +#include "threads.h" struct addr_location; struct branch_stack; @@ -28,16 +29,6 @@ extern const char *ref_reloc_sym_names[]; struct vdso_info; -#define THREADS__TABLE_BITS 8 -#define THREADS__TABLE_SIZE (1 << THREADS__TABLE_BITS) - -struct threads { - struct rb_root_cached entries; - struct rw_semaphore lock; - unsigned int nr; - struct thread *last_match; -}; - struct machine { struct rb_node rb_node; pid_t pid; @@ -48,7 +39,7 @@ struct machine { char *root_dir; char *mmap_name; char *kallsyms_filename; - struct threads threads[THREADS__TABLE_SIZE]; + struct threads threads; struct vdso_info *vdso_info; struct perf_env *env; struct dsos dsos; @@ -69,12 +60,6 @@ struct machine { bool trampolines_mapped; }; -static inline struct threads *machine__threads(struct machine *machine, pid_t tid) -{ - /* Cast it to handle tid == -1 */ - return &machine->threads[(unsigned int)tid % THREADS__TABLE_SIZE]; -} - /* * The main kernel (vmlinux) map */ @@ -220,7 +205,6 @@ bool machine__is(struct machine *machine, const char *arch); bool machine__normalized_is(struct machine *machine, const char *arch); int machine__nr_cpus_avail(struct machine *machine); -struct thread *__machine__findnew_thread(struct machine *machine, pid_t pid, pid_t tid); struct thread *machine__findnew_thread(struct machine *machine, pid_t pid, pid_t tid); struct dso *machine__findnew_dso_id(struct machine *machine, const char *filename, struct dso_id *id); diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c index c59ab4d79163..1aa8962dcf52 100644 --- a/tools/perf/util/thread.c +++ b/tools/perf/util/thread.c @@ -26,7 +26,7 @@ int thread__init_maps(struct thread *thread, struct machine *machine) if (pid == thread__tid(thread) || pid == -1) { thread__set_maps(thread, maps__new(machine)); } else { - struct thread *leader = __machine__findnew_thread(machine, pid, pid); + struct thread *leader = machine__findnew_thread(machine, pid, pid); if (leader) { thread__set_maps(thread, maps__get(thread__maps(leader))); diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h index 0df775b5c110..4b8f3e9e513b 100644 --- a/tools/perf/util/thread.h +++ b/tools/perf/util/thread.h @@ -3,7 +3,6 @@ #define __PERF_THREAD_H #include <linux/refcount.h> -#include <linux/rbtree.h> #include <linux/list.h> #include <stdio.h> #include <unistd.h> @@ -30,11 +29,6 @@ struct lbr_stitch { struct callchain_cursor_node *prev_lbr_cursor; }; -struct thread_rb_node { - struct rb_node rb_node; - struct thread *thread; -}; - DECLARE_RC_STRUCT(thread) { /** @maps: mmaps associated with this thread. */ struct maps *maps; diff --git a/tools/perf/util/threads.c b/tools/perf/util/threads.c new file mode 100644 index 000000000000..d984ec939c7b --- /dev/null +++ b/tools/perf/util/threads.c @@ -0,0 +1,244 @@ +// SPDX-License-Identifier: GPL-2.0 +#include "threads.h" +#include "machine.h" +#include "thread.h" + +struct thread_rb_node { + struct rb_node rb_node; + struct thread *thread; +}; + +static struct threads_table_entry *threads__table(struct threads *threads, pid_t tid) +{ + /* Cast it to handle tid == -1 */ + return &threads->table[(unsigned int)tid % THREADS__TABLE_SIZE]; +} + +void threads__init(struct threads *threads) +{ + for (int i = 0; i < THREADS__TABLE_SIZE; i++) { + struct threads_table_entry *table = &threads->table[i]; + + table->entries = RB_ROOT_CACHED; + init_rwsem(&table->lock); + table->nr = 0; + table->last_match = NULL; + } +} + +void threads__exit(struct threads *threads) +{ + threads__remove_all_threads(threads); + for (int i = 0; i < THREADS__TABLE_SIZE; i++) { + struct threads_table_entry *table = &threads->table[i]; + + exit_rwsem(&table->lock); + } +} + +size_t threads__nr(struct threads *threads) +{ + size_t nr = 0; + + for (int i = 0; i < THREADS__TABLE_SIZE; i++) { + struct threads_table_entry *table = &threads->table[i]; + + down_read(&table->lock); + nr += table->nr; + up_read(&table->lock); + } + return nr; +} + +/* + * Front-end cache - TID lookups come in blocks, + * so most of the time we dont have to look up + * the full rbtree: + */ +static struct thread *__threads_table_entry__get_last_match(struct threads_table_entry *table, + pid_t tid) +{ + struct thread *th, *res = NULL; + + th = table->last_match; + if (th != NULL) { + if (thread__tid(th) == tid) + res = thread__get(th); + } + return res; +} + +static void __threads_table_entry__set_last_match(struct threads_table_entry *table, + struct thread *th) +{ + thread__put(table->last_match); + table->last_match = thread__get(th); +} + +static void threads_table_entry__set_last_match(struct threads_table_entry *table, + struct thread *th) +{ + down_write(&table->lock); + __threads_table_entry__set_last_match(table, th); + up_write(&table->lock); +} + +struct thread *threads__find(struct threads *threads, pid_t tid) +{ + struct threads_table_entry *table = threads__table(threads, tid); + struct rb_node **p; + struct thread *res = NULL; + + down_read(&table->lock); + res = __threads_table_entry__get_last_match(table, tid); + if (res) + return res; + + p = &table->entries.rb_root.rb_node; + while (*p != NULL) { + struct rb_node *parent = *p; + struct thread *th = rb_entry(parent, struct thread_rb_node, rb_node)->thread; + + if (thread__tid(th) == tid) { + res = thread__get(th); + break; + } + + if (tid < thread__tid(th)) + p = &(*p)->rb_left; + else + p = &(*p)->rb_right; + } + up_read(&table->lock); + if (res) + threads_table_entry__set_last_match(table, res); + return res; +} + +struct thread *threads__findnew(struct threads *threads, pid_t pid, pid_t tid, bool *created) +{ + struct threads_table_entry *table = threads__table(threads, tid); + struct rb_node **p; + struct rb_node *parent = NULL; + struct thread *res = NULL; + struct thread_rb_node *nd; + bool leftmost = true; + + *created = false; + down_write(&table->lock); + p = &table->entries.rb_root.rb_node; + while (*p != NULL) { + struct thread *th; + + parent = *p; + th = rb_entry(parent, struct thread_rb_node, rb_node)->thread; + + if (thread__tid(th) == tid) { + __threads_table_entry__set_last_match(table, th); + res = thread__get(th); + goto out_unlock; + } + + if (tid < thread__tid(th)) + p = &(*p)->rb_left; + else { + leftmost = false; + p = &(*p)->rb_right; + } + } + nd = malloc(sizeof(*nd)); + if (nd == NULL) + goto out_unlock; + res = thread__new(pid, tid); + if (!res) + free(nd); + else { + *created = true; + nd->thread = thread__get(res); + rb_link_node(&nd->rb_node, parent, p); + rb_insert_color_cached(&nd->rb_node, &table->entries, leftmost); + ++table->nr; + __threads_table_entry__set_last_match(table, res); + } +out_unlock: + up_write(&table->lock); + return res; +} + +void threads__remove_all_threads(struct threads *threads) +{ + for (int i = 0; i < THREADS__TABLE_SIZE; i++) { + struct threads_table_entry *table = &threads->table[i]; + struct rb_node *nd; + + down_write(&table->lock); + __threads_table_entry__set_last_match(table, NULL); + nd = rb_first_cached(&table->entries); + while (nd) { + struct thread_rb_node *trb = rb_entry(nd, struct thread_rb_node, rb_node); + + nd = rb_next(nd); + thread__put(trb->thread); + rb_erase_cached(&trb->rb_node, &table->entries); + RB_CLEAR_NODE(&trb->rb_node); + --table->nr; + + free(trb); + } + assert(table->nr == 0); + up_write(&table->lock); + } +} + +void threads__remove(struct threads *threads, struct thread *thread) +{ + struct rb_node **p; + struct threads_table_entry *table = threads__table(threads, thread__tid(thread)); + pid_t tid = thread__tid(thread); + + down_write(&table->lock); + if (table->last_match && RC_CHK_EQUAL(table->last_match, thread)) + __threads_table_entry__set_last_match(table, NULL); + + p = &table->entries.rb_root.rb_node; + while (*p != NULL) { + struct rb_node *parent = *p; + struct thread_rb_node *nd = rb_entry(parent, struct thread_rb_node, rb_node); + struct thread *th = nd->thread; + + if (RC_CHK_EQUAL(th, thread)) { + thread__put(nd->thread); + rb_erase_cached(&nd->rb_node, &table->entries); + RB_CLEAR_NODE(&nd->rb_node); + --table->nr; + free(nd); + break; + } + + if (tid < thread__tid(th)) + p = &(*p)->rb_left; + else + p = &(*p)->rb_right; + } + up_write(&table->lock); +} + +int threads__for_each_thread(struct threads *threads, + int (*fn)(struct thread *thread, void *data), + void *data) +{ + for (int i = 0; i < THREADS__TABLE_SIZE; i++) { + struct threads_table_entry *table = &threads->table[i]; + struct rb_node *nd; + + for (nd = rb_first_cached(&table->entries); nd; nd = rb_next(nd)) { + struct thread_rb_node *trb = rb_entry(nd, struct thread_rb_node, rb_node); + int rc = fn(trb->thread, data); + + if (rc != 0) + return rc; + } + } + return 0; + +} diff --git a/tools/perf/util/threads.h b/tools/perf/util/threads.h new file mode 100644 index 000000000000..ed67de627578 --- /dev/null +++ b/tools/perf/util/threads.h @@ -0,0 +1,35 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __PERF_THREADS_H +#define __PERF_THREADS_H + +#include <linux/rbtree.h> +#include "rwsem.h" + +struct thread; + +#define THREADS__TABLE_BITS 8 +#define THREADS__TABLE_SIZE (1 << THREADS__TABLE_BITS) + +struct threads_table_entry { + struct rb_root_cached entries; + struct rw_semaphore lock; + unsigned int nr; + struct thread *last_match; +}; + +struct threads { + struct threads_table_entry table[THREADS__TABLE_SIZE]; +}; + +void threads__init(struct threads *threads); +void threads__exit(struct threads *threads); +size_t threads__nr(struct threads *threads); +struct thread *threads__find(struct threads *threads, pid_t tid); +struct thread *threads__findnew(struct threads *threads, pid_t pid, pid_t tid, bool *created); +void threads__remove_all_threads(struct threads *threads); +void threads__remove(struct threads *threads, struct thread *thread); +int threads__for_each_thread(struct threads *threads, + int (*fn)(struct thread *thread, void *data), + void *data); + +#endif /* __PERF_THREADS_H */ -- 2.43.0.687.g38aa6559b0-goog