diff options
Diffstat (limited to 'tools/perf')
| -rw-r--r-- | tools/perf/builtin-record.c | 5 | ||||
| -rw-r--r-- | tools/perf/util/evlist.c | 62 | ||||
| -rw-r--r-- | tools/perf/util/evlist.h | 31 |
3 files changed, 98 insertions, 0 deletions
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index dbcb22304398..d4f15e76c98a 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -513,6 +513,9 @@ static int record__mmap_read_evlist(struct record *rec, struct perf_evlist *evli if (!maps) return 0; + if (backward && evlist->bkw_mmap_state != BKW_MMAP_DATA_PENDING) + return 0; + for (i = 0; i < evlist->nr_mmaps; i++) { struct auxtrace_mmap *mm = &maps[i].auxtrace_mmap; @@ -538,6 +541,8 @@ static int record__mmap_read_evlist(struct record *rec, struct perf_evlist *evli if (bytes_written != rec->bytes_written) rc = record__write(rec, &finished_round_event, sizeof(finished_round_event)); + if (backward) + perf_evlist__toggle_bkw_mmap(evlist, BKW_MMAP_EMPTY); out: return rc; } diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index 5beb44faa71d..93ab66415f51 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -15,6 +15,7 @@ #include "evlist.h" #include "evsel.h" #include "debug.h" +#include "asm/bug.h" #include <unistd.h> #include "parse-events.h" @@ -44,6 +45,7 @@ void perf_evlist__init(struct perf_evlist *evlist, struct cpu_map *cpus, perf_evlist__set_maps(evlist, cpus, threads); fdarray__init(&evlist->pollfd, 64); evlist->workload.pid = -1; + evlist->bkw_mmap_state = BKW_MMAP_NOTREADY; } struct perf_evlist *perf_evlist__new(void) @@ -1068,6 +1070,8 @@ static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int idx, if (!maps) return -1; evlist->backward_mmap = maps; + if (evlist->bkw_mmap_state == BKW_MMAP_NOTREADY) + perf_evlist__toggle_bkw_mmap(evlist, BKW_MMAP_RUNNING); } } @@ -1972,3 +1976,61 @@ perf_evlist__find_evsel_by_str(struct perf_evlist *evlist, return NULL; } + +void perf_evlist__toggle_bkw_mmap(struct perf_evlist *evlist, + enum bkw_mmap_state state) +{ + enum bkw_mmap_state old_state = evlist->bkw_mmap_state; + enum action { + NONE, + PAUSE, + RESUME, + } action = NONE; + + if (!evlist->backward_mmap) + return; + + switch (old_state) { + case BKW_MMAP_NOTREADY: { + if (state != BKW_MMAP_RUNNING) + goto state_err;; + break; + } + case BKW_MMAP_RUNNING: { + if (state != BKW_MMAP_DATA_PENDING) + goto state_err; + action = PAUSE; + break; + } + case BKW_MMAP_DATA_PENDING: { + if (state != BKW_MMAP_EMPTY) + goto state_err; + break; + } + case BKW_MMAP_EMPTY: { + if (state != BKW_MMAP_RUNNING) + goto state_err; + action = RESUME; + break; + } + default: + WARN_ONCE(1, "Shouldn't get there\n"); + } + + evlist->bkw_mmap_state = state; + + switch (action) { + case PAUSE: + perf_evlist__pause(evlist); + break; + case RESUME: + perf_evlist__resume(evlist); + break; + case NONE: + default: + break; + } + +state_err: + return; +} diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h index 6a3d9bdda4bb..20faaab1941c 100644 --- a/tools/perf/util/evlist.h +++ b/tools/perf/util/evlist.h @@ -41,6 +41,34 @@ perf_mmap__mmap_len(struct perf_mmap *map) return map->mask + 1 + page_size; } +/* + * State machine of bkw_mmap_state: + * + * .________________(forbid)_____________. + * | V + * NOTREADY --(0)--> RUNNING --(1)--> DATA_PENDING --(2)--> EMPTY + * ^ ^ | ^ | + * | |__(forbid)____/ |___(forbid)___/| + * | | + * \_________________(3)_______________/ + * + * NOTREADY : Backward ring buffers are not ready + * RUNNING : Backward ring buffers are recording + * DATA_PENDING : We are required to collect data from backward ring buffers + * EMPTY : We have collected data from backward ring buffers. + * + * (0): Setup backward ring buffer + * (1): Pause ring buffers for reading + * (2): Read from ring buffers + * (3): Resume ring buffers for recording + */ +enum bkw_mmap_state { + BKW_MMAP_NOTREADY, + BKW_MMAP_RUNNING, + BKW_MMAP_DATA_PENDING, + BKW_MMAP_EMPTY, +}; + struct perf_evlist { struct list_head entries; struct hlist_head heads[PERF_EVLIST__HLIST_SIZE]; @@ -54,6 +82,7 @@ struct perf_evlist { int id_pos; int is_pos; u64 combined_sample_type; + enum bkw_mmap_state bkw_mmap_state; struct { int cork_fd; pid_t pid; @@ -135,6 +164,8 @@ struct perf_evsel *perf_evlist__id2evsel_strict(struct perf_evlist *evlist, struct perf_sample_id *perf_evlist__id2sid(struct perf_evlist *evlist, u64 id); +void perf_evlist__toggle_bkw_mmap(struct perf_evlist *evlist, enum bkw_mmap_state state); + union perf_event *perf_mmap__read_forward(struct perf_mmap *map, bool check_messup); union perf_event *perf_mmap__read_backward(struct perf_mmap *map); |