commit f8baa40c01917a6261dd6824097cee98e8ace514 Author: Nick Mathewson <nickm@torproject.org> Date: Wed Jan 7 11:37:23 2015 -0500 GETINFO bw-event-cache to get information on recent BW events Closes 14128; useful to regain functionality lost because of 13988. --- changes/ticket14128 | 5 +++++ src/or/control.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++ src/or/control.h | 1 + 3 files changed, 56 insertions(+) diff --git a/changes/ticket14128 b/changes/ticket14128 new file mode 100644 index 0000000..38b25fa --- /dev/null +++ b/changes/ticket14128 @@ -0,0 +1,5 @@ + o Minor features (controller): + - New "GETINFO bw-event-cache" to get information about recent bandwidth + events. Closes ticket 14128. Useful for controllers to get recent + bandwidth history after the fix for 13988. + diff --git a/src/or/control.c b/src/or/control.c index 3dbaa1b..9ff71c9 100644 --- a/src/or/control.c +++ b/src/or/control.c @@ -1438,6 +1438,8 @@ getinfo_helper_misc(control_connection_t *conn, const char *question, (void) conn; if (!strcmp(question, "version")) { *answer = tor_strdup(get_version()); + } else if (!strcmp(question, "bw-event-cache")) { + *answer = get_bw_samples(); } else if (!strcmp(question, "config-file")) { *answer = tor_strdup(get_torrc_fname(0)); } else if (!strcmp(question, "config-defaults-file")) { @@ -2113,6 +2115,7 @@ typedef struct getinfo_item_t { * to answer them. */ static const getinfo_item_t getinfo_items[] = { ITEM("version", misc, "The current version of Tor."), + ITEM("bw-event-cache", misc, "Cached BW events for a short interval."), ITEM("config-file", misc, "Current location of the \"torrc\" file."), ITEM("config-defaults-file", misc, "Current location of the defaults file."), ITEM("config-text", misc, @@ -4155,11 +4158,29 @@ control_event_tb_empty(const char *bucket, uint32_t read_empty_time, return 0; } +/* about 5 minutes worth. */ +#define N_BW_EVENTS_TO_CACHE 300 +/* Index into cached_bw_events to next write. */ +static int next_measurement_idx = 0; +/* number of entries set in n_measurements */ +static int n_measurements = 0; +static struct cached_bw_event_s { + uint32_t n_read; + uint32_t n_written; +} cached_bw_events[N_BW_EVENTS_TO_CACHE]; + /** A second or more has elapsed: tell any interested control * connections how much bandwidth we used. */ int control_event_bandwidth_used(uint32_t n_read, uint32_t n_written) { + cached_bw_events[next_measurement_idx].n_read = n_read; + cached_bw_events[next_measurement_idx].n_written = n_written; + if (++next_measurement_idx == N_BW_EVENTS_TO_CACHE) + next_measurement_idx = 0; + if (n_measurements < N_BW_EVENTS_TO_CACHE) + ++n_measurements; + if (EVENT_IS_INTERESTING(EVENT_BANDWIDTH_USED)) { send_control_event(EVENT_BANDWIDTH_USED, ALL_FORMATS, "650 BW %lu %lu\r\n", @@ -4170,6 +4191,35 @@ control_event_bandwidth_used(uint32_t n_read, uint32_t n_written) return 0; } +STATIC char * +get_bw_samples(void) +{ + int i; + int idx = (next_measurement_idx + N_BW_EVENTS_TO_CACHE - n_measurements) + % N_BW_EVENTS_TO_CACHE; + tor_assert(0 <= idx && idx < N_BW_EVENTS_TO_CACHE); + + smartlist_t *elements = smartlist_new(); + + for (i = 0; i < n_measurements; ++i) { + tor_assert(0 <= idx && idx < N_BW_EVENTS_TO_CACHE); + const struct cached_bw_event_s *bwe = &cached_bw_events[idx]; + + smartlist_add_asprintf(elements, "%u,%u", + (unsigned)bwe->n_read, + (unsigned)bwe->n_written); + + idx = (idx + 1) % N_BW_EVENTS_TO_CACHE; + } + + char *result = smartlist_join_strings(elements, " ", 0, NULL); + + SMARTLIST_FOREACH(elements, char *, cp, tor_free(cp)); + smartlist_free(elements); + + return result; +} + /** Called when we are sending a log message to the controllers: suspend * sending further log messages to the controllers until we're done. Used by * CONN_LOG_PROTECT. */ diff --git a/src/or/control.h b/src/or/control.h index 0af09ae..8c9f7bb 100644 --- a/src/or/control.h +++ b/src/or/control.h @@ -203,6 +203,7 @@ void append_cell_stats_by_command(smartlist_t *event_parts, const uint64_t *number_to_include); void format_cell_stats(char **event_string, circuit_t *circ, cell_stats_t *cell_stats); +STATIC char *get_bw_samples(void); #endif #endif