From: Tom Zanussi Date: Fri, 2 Apr 2010 04:59:15 +0000 (-0500) Subject: perf: Add pipe-specific header read/write and event processing code X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=8dc58101f2c838355d44402aa77646649d10dbec;p=openwrt%2Fstaging%2Fblogic.git perf: Add pipe-specific header read/write and event processing code This patch makes several changes to allow the perf event stream to be sent and received over a pipe: - adds pipe-specific versions of the header read/write code - adds pipe-specific version of the event processing code - adds a range of event types to be used for header or other pseudo events, above the range used by the kernel - checks the return value of event handlers, which they can use to skip over large events during event processing rather than actually reading them into event objects. - unifies the multiple do_read() functions and updates its users. Note that none of these changes affect the existing perf data file format or processing - this code only comes into play if perf output is sent to stdout (or is read from stdin). Signed-off-by: Tom Zanussi Acked-by: Thomas Gleixner Cc: fweisbec@gmail.com Cc: rostedt@goodmis.org Cc: k-keiichi@bx.jp.nec.com Cc: acme@ghostprotocols.net LKML-Reference: <1270184365-8281-2-git-send-email-tzanussi@gmail.com> Signed-off-by: Ingo Molnar --- diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 9a9513687235..d060fc50c8a4 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -487,7 +487,7 @@ static int __cmd_record(int argc, const char **argv) } if (!file_new) { - err = perf_header__read(&session->header, output); + err = perf_header__read(session, output); if (err < 0) return err; } diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h index 7f7cf8539cfe..5c1eba671305 100644 --- a/tools/perf/util/event.h +++ b/tools/perf/util/event.h @@ -83,6 +83,10 @@ struct build_id_event { char filename[]; }; +enum perf_header_event_type { /* above any possible kernel type */ + PERF_RECORD_HEADER_MAX = 64, +}; + typedef union event_union { struct perf_event_header header; struct ip_event ip; diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c index 6c9aa16ee51f..8d05337d1a59 100644 --- a/tools/perf/util/header.c +++ b/tools/perf/util/header.c @@ -427,6 +427,25 @@ out_free: return err; } +int perf_header__write_pipe(int fd) +{ + struct perf_pipe_file_header f_header; + int err; + + f_header = (struct perf_pipe_file_header){ + .magic = PERF_MAGIC, + .size = sizeof(f_header), + }; + + err = do_write(fd, &f_header, sizeof(f_header)); + if (err < 0) { + pr_debug("failed to write perf pipe header\n"); + return err; + } + + return 0; +} + int perf_header__write(struct perf_header *self, int fd, bool at_exit) { struct perf_file_header f_header; @@ -518,25 +537,10 @@ int perf_header__write(struct perf_header *self, int fd, bool at_exit) return 0; } -static int do_read(int fd, void *buf, size_t size) -{ - while (size) { - int ret = read(fd, buf, size); - - if (ret <= 0) - return -1; - - size -= ret; - buf += ret; - } - - return 0; -} - static int perf_header__getbuffer64(struct perf_header *self, int fd, void *buf, size_t size) { - if (do_read(fd, buf, size)) + if (do_read(fd, buf, size) <= 0) return -1; if (self->needs_swap) @@ -592,7 +596,7 @@ int perf_file_header__read(struct perf_file_header *self, { lseek(fd, 0, SEEK_SET); - if (do_read(fd, self, sizeof(*self)) || + if (do_read(fd, self, sizeof(*self)) <= 0 || memcmp(&self->magic, __perf_magic, sizeof(self->magic))) return -1; @@ -662,13 +666,51 @@ static int perf_file_section__process(struct perf_file_section *self, return 0; } -int perf_header__read(struct perf_header *self, int fd) +static int perf_file_header__read_pipe(struct perf_pipe_file_header *self, + struct perf_header *ph, int fd) { + if (do_read(fd, self, sizeof(*self)) <= 0 || + memcmp(&self->magic, __perf_magic, sizeof(self->magic))) + return -1; + + if (self->size != sizeof(*self)) { + u64 size = bswap_64(self->size); + + if (size != sizeof(*self)) + return -1; + + ph->needs_swap = true; + } + + return 0; +} + +static int perf_header__read_pipe(struct perf_session *session, int fd) +{ + struct perf_header *self = &session->header; + struct perf_pipe_file_header f_header; + + if (perf_file_header__read_pipe(&f_header, self, fd) < 0) { + pr_debug("incompatible file format\n"); + return -EINVAL; + } + + session->fd = fd; + + return 0; +} + +int perf_header__read(struct perf_session *session, int fd) +{ + struct perf_header *self = &session->header; struct perf_file_header f_header; struct perf_file_attr f_attr; u64 f_id; int nr_attrs, nr_ids, i, j; + if (session->fd_pipe) + return perf_header__read_pipe(session, fd); + if (perf_file_header__read(&f_header, self, fd) < 0) { pr_debug("incompatible file format\n"); return -EINVAL; diff --git a/tools/perf/util/header.h b/tools/perf/util/header.h index c059f08cf877..6562ece67064 100644 --- a/tools/perf/util/header.h +++ b/tools/perf/util/header.h @@ -39,6 +39,11 @@ struct perf_file_header { DECLARE_BITMAP(adds_features, HEADER_FEAT_BITS); }; +struct perf_pipe_file_header { + u64 magic; + u64 size; +}; + struct perf_header; int perf_file_header__read(struct perf_file_header *self, @@ -60,8 +65,9 @@ struct perf_header { int perf_header__init(struct perf_header *self); void perf_header__exit(struct perf_header *self); -int perf_header__read(struct perf_header *self, int fd); +int perf_header__read(struct perf_session *session, int fd); int perf_header__write(struct perf_header *self, int fd, bool at_exit); +int perf_header__write_pipe(int fd); int perf_header__add_attr(struct perf_header *self, struct perf_header_attr *attr); diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c index ddf288fca3eb..2c1277cb4ae4 100644 --- a/tools/perf/util/session.c +++ b/tools/perf/util/session.c @@ -14,6 +14,16 @@ static int perf_session__open(struct perf_session *self, bool force) { struct stat input_stat; + if (!strcmp(self->filename, "-")) { + self->fd_pipe = true; + self->fd = STDIN_FILENO; + + if (perf_header__read(self, self->fd) < 0) + pr_err("incompatible file format"); + + return 0; + } + self->fd = open(self->filename, O_RDONLY); if (self->fd < 0) { pr_err("failed to open file: %s", self->filename); @@ -38,7 +48,7 @@ static int perf_session__open(struct perf_session *self, bool force) goto out_close; } - if (perf_header__read(&self->header, self->fd) < 0) { + if (perf_header__read(self, self->fd) < 0) { pr_err("incompatible file format"); goto out_close; } @@ -52,6 +62,11 @@ out_close: return -1; } +void perf_session__update_sample_type(struct perf_session *self) +{ + self->sample_type = perf_header__sample_type(&self->header); +} + struct perf_session *perf_session__new(const char *filename, int mode, bool force) { size_t len = filename ? strlen(filename) + 1 : 0; @@ -85,7 +100,7 @@ struct perf_session *perf_session__new(const char *filename, int mode, bool forc goto out_delete; } - self->sample_type = perf_header__sample_type(&self->header); + perf_session__update_sample_type(self); out: return self; out_free: @@ -200,14 +215,17 @@ static const char *event__name[] = { [PERF_RECORD_SAMPLE] = "SAMPLE", }; -unsigned long event__total[PERF_RECORD_MAX]; +unsigned long event__total[PERF_RECORD_HEADER_MAX]; void event__print_totals(void) { int i; - for (i = 0; i < PERF_RECORD_MAX; ++i) + for (i = 0; i < PERF_RECORD_HEADER_MAX; ++i) { + if (!event__name[i]) + continue; pr_info("%10s events: %10ld\n", event__name[i], event__total[i]); + } } void mem_bswap_64(void *src, int byte_size) @@ -271,7 +289,7 @@ static event__swap_op event__swap_ops[] = { [PERF_RECORD_LOST] = event__all64_swap, [PERF_RECORD_READ] = event__read_swap, [PERF_RECORD_SAMPLE] = event__all64_swap, - [PERF_RECORD_MAX] = NULL, + [PERF_RECORD_HEADER_MAX] = NULL, }; static int perf_session__process_event(struct perf_session *self, @@ -281,7 +299,7 @@ static int perf_session__process_event(struct perf_session *self, { trace_event(event); - if (event->header.type < PERF_RECORD_MAX) { + if (event->header.type < PERF_RECORD_HEADER_MAX) { dump_printf("%#Lx [%#x]: PERF_RECORD_%s", offset + head, event->header.size, event__name[event->header.type]); @@ -376,6 +394,101 @@ static struct thread *perf_session__register_idle_thread(struct perf_session *se return thread; } +int do_read(int fd, void *buf, size_t size) +{ + void *buf_start = buf; + + while (size) { + int ret = read(fd, buf, size); + + if (ret <= 0) + return ret; + + size -= ret; + buf += ret; + } + + return buf - buf_start; +} + +#define session_done() (*(volatile int *)(&session_done)) +volatile int session_done; + +static int __perf_session__process_pipe_events(struct perf_session *self, + struct perf_event_ops *ops) +{ + event_t event; + uint32_t size; + int skip = 0; + u64 head; + int err; + void *p; + + perf_event_ops__fill_defaults(ops); + + head = 0; +more: + err = do_read(self->fd, &event, sizeof(struct perf_event_header)); + if (err <= 0) { + if (err == 0) + goto done; + + pr_err("failed to read event header\n"); + goto out_err; + } + + if (self->header.needs_swap) + perf_event_header__bswap(&event.header); + + size = event.header.size; + if (size == 0) + size = 8; + + p = &event; + p += sizeof(struct perf_event_header); + + err = do_read(self->fd, p, size - sizeof(struct perf_event_header)); + if (err <= 0) { + if (err == 0) { + pr_err("unexpected end of event stream\n"); + goto done; + } + + pr_err("failed to read event data\n"); + goto out_err; + } + + if (size == 0 || + (skip = perf_session__process_event(self, &event, ops, + 0, head)) < 0) { + dump_printf("%#Lx [%#x]: skipping unknown header type: %d\n", + head, event.header.size, event.header.type); + /* + * assume we lost track of the stream, check alignment, and + * increment a single u64 in the hope to catch on again 'soon'. + */ + if (unlikely(head & 7)) + head &= ~7ULL; + + size = 8; + } + + head += size; + + dump_printf("\n%#Lx [%#x]: event: %d\n", + head, event.header.size, event.header.type); + + if (skip > 0) + head += skip; + + if (!session_done()) + goto more; +done: + err = 0; +out_err: + return err; +} + int __perf_session__process_events(struct perf_session *self, u64 data_offset, u64 data_size, u64 file_size, struct perf_event_ops *ops) @@ -499,9 +612,13 @@ out_getcwd_err: self->cwdlen = strlen(self->cwd); } - err = __perf_session__process_events(self, self->header.data_offset, - self->header.data_size, - self->size, ops); + if (!self->fd_pipe) + err = __perf_session__process_events(self, + self->header.data_offset, + self->header.data_size, + self->size, ops); + else + err = __perf_session__process_pipe_events(self, ops); out_err: return err; } diff --git a/tools/perf/util/session.h b/tools/perf/util/session.h index 27f4c2dc715b..5f7891136655 100644 --- a/tools/perf/util/session.h +++ b/tools/perf/util/session.h @@ -27,6 +27,7 @@ struct perf_session { u64 sample_type; struct ref_reloc_sym ref_reloc_sym; int fd; + bool fd_pipe; int cwdlen; char *cwd; char filename[0]; @@ -92,6 +93,9 @@ static inline struct map * return map_groups__new_module(&self->kmaps, start, filename); } +int do_read(int fd, void *buf, size_t size); +void perf_session__update_sample_type(struct perf_session *self); + #ifdef NO_NEWT_SUPPORT static inline int perf_session__browse_hists(struct rb_root *hists __used, u64 nr_hists __used,