diff options
| -rw-r--r-- | include/uapi/linux/perf_event.h | 2 | ||||
| -rw-r--r-- | tools/include/uapi/linux/perf_event.h | 2 | ||||
| -rw-r--r-- | tools/perf/util/event.c | 1 | ||||
| -rw-r--r-- | tools/perf/util/machine.c | 19 | ||||
| -rw-r--r-- | tools/perf/util/thread.c | 13 | ||||
| -rw-r--r-- | tools/perf/util/thread.h | 2 |
6 files changed, 29 insertions, 10 deletions
diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h index f35eb72739c0..9de8780ac8d9 100644 --- a/include/uapi/linux/perf_event.h +++ b/include/uapi/linux/perf_event.h @@ -646,10 +646,12 @@ struct perf_event_mmap_page { * * PERF_RECORD_MISC_MMAP_DATA - PERF_RECORD_MMAP* events * PERF_RECORD_MISC_COMM_EXEC - PERF_RECORD_COMM event + * PERF_RECORD_MISC_FORK_EXEC - PERF_RECORD_FORK event (perf internal) * PERF_RECORD_MISC_SWITCH_OUT - PERF_RECORD_SWITCH* events */ #define PERF_RECORD_MISC_MMAP_DATA (1 << 13) #define PERF_RECORD_MISC_COMM_EXEC (1 << 13) +#define PERF_RECORD_MISC_FORK_EXEC (1 << 13) #define PERF_RECORD_MISC_SWITCH_OUT (1 << 13) /* * These PERF_RECORD_MISC_* flags below are safely reused diff --git a/tools/include/uapi/linux/perf_event.h b/tools/include/uapi/linux/perf_event.h index f35eb72739c0..9de8780ac8d9 100644 --- a/tools/include/uapi/linux/perf_event.h +++ b/tools/include/uapi/linux/perf_event.h @@ -646,10 +646,12 @@ struct perf_event_mmap_page { * * PERF_RECORD_MISC_MMAP_DATA - PERF_RECORD_MMAP* events * PERF_RECORD_MISC_COMM_EXEC - PERF_RECORD_COMM event + * PERF_RECORD_MISC_FORK_EXEC - PERF_RECORD_FORK event (perf internal) * PERF_RECORD_MISC_SWITCH_OUT - PERF_RECORD_SWITCH* events */ #define PERF_RECORD_MISC_MMAP_DATA (1 << 13) #define PERF_RECORD_MISC_COMM_EXEC (1 << 13) +#define PERF_RECORD_MISC_FORK_EXEC (1 << 13) #define PERF_RECORD_MISC_SWITCH_OUT (1 << 13) /* * These PERF_RECORD_MISC_* flags below are safely reused diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c index bc646185f8d9..e9c108a6b1c3 100644 --- a/tools/perf/util/event.c +++ b/tools/perf/util/event.c @@ -308,6 +308,7 @@ static int perf_event__synthesize_fork(struct perf_tool *tool, event->fork.pid = tgid; event->fork.tid = pid; event->fork.header.type = PERF_RECORD_FORK; + event->fork.header.misc = PERF_RECORD_MISC_FORK_EXEC; event->fork.header.size = (sizeof(event->fork) + machine->id_hdr_size); diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index 8ee8ab39d8ac..8f36ce813bc5 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -1708,6 +1708,7 @@ int machine__process_fork_event(struct machine *machine, union perf_event *event struct thread *parent = machine__findnew_thread(machine, event->fork.ppid, event->fork.ptid); + bool do_maps_clone = true; int err = 0; if (dump_trace) @@ -1736,9 +1737,25 @@ int machine__process_fork_event(struct machine *machine, union perf_event *event thread = machine__findnew_thread(machine, event->fork.pid, event->fork.tid); + /* + * When synthesizing FORK events, we are trying to create thread + * objects for the already running tasks on the machine. + * + * Normally, for a kernel FORK event, we want to clone the parent's + * maps because that is what the kernel just did. + * + * But when synthesizing, this should not be done. If we do, we end up + * with overlapping maps as we process the sythesized MMAP2 events that + * get delivered shortly thereafter. + * + * Use the FORK event misc flags in an internal way to signal this + * situation, so we can elide the map clone when appropriate. + */ + if (event->fork.header.misc & PERF_RECORD_MISC_FORK_EXEC) + do_maps_clone = false; if (thread == NULL || parent == NULL || - thread__fork(thread, parent, sample->time) < 0) { + thread__fork(thread, parent, sample->time, do_maps_clone) < 0) { dump_printf("problem processing PERF_RECORD_FORK, skipping event.\n"); err = -1; } diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c index 2048d393ece6..3d9ed7d0e281 100644 --- a/tools/perf/util/thread.c +++ b/tools/perf/util/thread.c @@ -330,7 +330,8 @@ static int thread__prepare_access(struct thread *thread) } static int thread__clone_map_groups(struct thread *thread, - struct thread *parent) + struct thread *parent, + bool do_maps_clone) { /* This is new thread, we share map groups for process. */ if (thread->pid_ == parent->pid_) @@ -341,15 +342,11 @@ static int thread__clone_map_groups(struct thread *thread, thread->pid_, thread->tid, parent->pid_, parent->tid); return 0; } - /* But this one is new process, copy maps. */ - if (map_groups__clone(thread, parent->mg) < 0) - return -ENOMEM; - - return 0; + return do_maps_clone ? map_groups__clone(thread, parent->mg) : 0; } -int thread__fork(struct thread *thread, struct thread *parent, u64 timestamp) +int thread__fork(struct thread *thread, struct thread *parent, u64 timestamp, bool do_maps_clone) { if (parent->comm_set) { const char *comm = thread__comm_str(parent); @@ -362,7 +359,7 @@ int thread__fork(struct thread *thread, struct thread *parent, u64 timestamp) } thread->ppid = parent->tid; - return thread__clone_map_groups(thread, parent); + return thread__clone_map_groups(thread, parent, do_maps_clone); } void thread__find_cpumode_addr_location(struct thread *thread, u64 addr, diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h index 36c09a9904e6..30e2b4c165fe 100644 --- a/tools/perf/util/thread.h +++ b/tools/perf/util/thread.h @@ -89,7 +89,7 @@ struct comm *thread__comm(const struct thread *thread); struct comm *thread__exec_comm(const struct thread *thread); const char *thread__comm_str(const struct thread *thread); int thread__insert_map(struct thread *thread, struct map *map); -int thread__fork(struct thread *thread, struct thread *parent, u64 timestamp); +int thread__fork(struct thread *thread, struct thread *parent, u64 timestamp, bool do_maps_clone); size_t thread__fprintf(struct thread *thread, FILE *fp); struct thread *thread__main_thread(struct machine *machine, struct thread *thread); |