From 6c6c5927a1e16e347a0e353904241694b21b57f9 Mon Sep 17 00:00:00 2001 From: Stefan Metzmacher Date: Fri, 4 May 2007 09:22:52 +0000 Subject: r22661: optimize the handling of directly triggered timed events: - if someone adds a timed_event with a zero timeval we now avoid serval gettimeofday() calls and the event handler doesn't get the current time when it's called, instead we also pass a zero timeval - this also makes sure multiple timed events with a zero timeval are processed in the order there're added. the little benchmark shows that processing 2000000 directly timed events is now much faster, while avoiding syscalls at all! > time ./evtest (with the old code) real 0m6.388s user 0m1.740s sys 0m4.632s > time ./evtest (with the new code) real 0m1.498s user 0m1.496s sys 0m0.004s metze@SERNOX:~/devel/samba/4.0/samba4-ci/source> cat evtest.c #include #include #include #include #include static void dummy_fde_handler(struct event_context *ev_ctx, struct fd_event *fde, uint16_t flags, void *private_data) { } static void timeout_handler(struct event_context *ev, struct timed_event *te, struct timeval tval, void *private_data) { uint32_t *countp = (uint32_t *)private_data; (*countp)++; if (*countp > 2000000) exit(0); event_add_timed(ev, ev, tval, timeout_handler, countp); } int main(void) { struct event_context *ev; struct timeval tval = { 0, 0 }; uint32_t count = 0; ev = event_context_init(NULL); event_add_fd(ev, ev, 0, 0, dummy_fde_handler, NULL); event_add_timed(ev, ev, tval, timeout_handler, &count); return event_loop_wait(ev); } (This used to be commit 4db64b4ce2320b88d648078cbf86385f6fb44f1f) --- source4/lib/events/events_aio.c | 7 ++-- source4/lib/events/events_epoll.c | 7 ++-- source4/lib/events/events_internal.h | 3 +- source4/lib/events/events_select.c | 7 ++-- source4/lib/events/events_standard.c | 10 ++--- source4/lib/events/events_timed.c | 74 ++++++++++++++++++++++-------------- 6 files changed, 60 insertions(+), 48 deletions(-) (limited to 'source4/lib') diff --git a/source4/lib/events/events_aio.c b/source4/lib/events/events_aio.c index 9f4e9c5612..0eadcf5fec 100644 --- a/source4/lib/events/events_aio.c +++ b/source4/lib/events/events_aio.c @@ -250,7 +250,8 @@ static int aio_event_loop(struct aio_event_context *aio_ev, struct timeval *tval } if (ret == 0 && tvalp) { - common_event_loop_timer(aio_ev->ev); + /* we don't care about a possible delay here */ + common_event_loop_timer_delay(aio_ev->ev); return 0; } @@ -431,10 +432,8 @@ static int aio_event_loop_once(struct event_context *ev) struct aio_event_context); struct timeval tval; - tval = common_event_loop_delay(ev); - + tval = common_event_loop_timer_delay(ev); if (timeval_is_zero(&tval)) { - common_event_loop_timer(ev); return 0; } diff --git a/source4/lib/events/events_epoll.c b/source4/lib/events/events_epoll.c index 41a6509e36..2f879cc410 100644 --- a/source4/lib/events/events_epoll.c +++ b/source4/lib/events/events_epoll.c @@ -233,7 +233,8 @@ static int epoll_event_loop(struct epoll_event_context *epoll_ev, struct timeval } if (ret == 0 && tvalp) { - common_event_loop_timer(epoll_ev->ev); + /* we don't care about a possible delay here */ + common_event_loop_timer_delay(epoll_ev->ev); return 0; } @@ -376,10 +377,8 @@ static int epoll_event_loop_once(struct event_context *ev) struct epoll_event_context); struct timeval tval; - tval = common_event_loop_delay(ev); - + tval = common_event_loop_timer_delay(ev); if (timeval_is_zero(&tval)) { - common_event_loop_timer(ev); return 0; } diff --git a/source4/lib/events/events_internal.h b/source4/lib/events/events_internal.h index 04b92df550..fb15665c0a 100644 --- a/source4/lib/events/events_internal.h +++ b/source4/lib/events/events_internal.h @@ -117,8 +117,7 @@ bool event_register_backend(const char *name, const struct event_ops *ops); struct timed_event *common_event_add_timed(struct event_context *, TALLOC_CTX *, struct timeval, event_timed_handler_t, void *); -void common_event_loop_timer(struct event_context *); -struct timeval common_event_loop_delay(struct event_context *); +struct timeval common_event_loop_timer_delay(struct event_context *); struct signal_event *common_event_add_signal(struct event_context *ev, TALLOC_CTX *mem_ctx, diff --git a/source4/lib/events/events_select.c b/source4/lib/events/events_select.c index 291ddbde2b..b2f9cacf5f 100644 --- a/source4/lib/events/events_select.c +++ b/source4/lib/events/events_select.c @@ -218,7 +218,8 @@ static int select_event_loop_select(struct select_event_context *select_ev, stru } if (selrtn == 0 && tvalp) { - common_event_loop_timer(select_ev->ev); + /* we don't care about a possible delay here */ + common_event_loop_timer_delay(select_ev->ev); return 0; } @@ -252,10 +253,8 @@ static int select_event_loop_once(struct event_context *ev) struct select_event_context); struct timeval tval; - tval = common_event_loop_delay(ev); - + tval = common_event_loop_timer_delay(ev); if (timeval_is_zero(&tval)) { - common_event_loop_timer(ev); return 0; } diff --git a/source4/lib/events/events_standard.c b/source4/lib/events/events_standard.c index 8495ccdec0..dcf890ac12 100644 --- a/source4/lib/events/events_standard.c +++ b/source4/lib/events/events_standard.c @@ -248,7 +248,8 @@ static int epoll_event_loop(struct std_event_context *std_ev, struct timeval *tv } if (ret == 0 && tvalp) { - common_event_loop_timer(std_ev->ev); + /* we don't care about a possible delay here */ + common_event_loop_timer_delay(std_ev->ev); return 0; } @@ -471,7 +472,8 @@ static int std_event_loop_select(struct std_event_context *std_ev, struct timeva } if (selrtn == 0 && tvalp) { - common_event_loop_timer(std_ev->ev); + /* we don't care about a possible delay here */ + common_event_loop_timer_delay(std_ev->ev); return 0; } @@ -505,10 +507,8 @@ static int std_event_loop_once(struct event_context *ev) struct std_event_context); struct timeval tval; - tval = common_event_loop_delay(ev); - + tval = common_event_loop_timer_delay(ev); if (timeval_is_zero(&tval)) { - common_event_loop_timer(ev); return 0; } diff --git a/source4/lib/events/events_timed.c b/source4/lib/events/events_timed.c index c85f8371c1..31619dcb5f 100644 --- a/source4/lib/events/events_timed.c +++ b/source4/lib/events/events_timed.c @@ -68,9 +68,7 @@ struct timed_event *common_event_add_timed(struct event_context *ev, TALLOC_CTX last_te = NULL; for (cur_te = ev->timed_events; cur_te; cur_te = cur_te->next) { /* if the new event comes before the current one break */ - if (!timeval_is_zero(&cur_te->next_event) && - timeval_compare(&te->next_event, - &cur_te->next_event) < 0) { + if (timeval_compare(&te->next_event, &cur_te->next_event) < 0) { break; } @@ -85,17 +83,47 @@ struct timed_event *common_event_add_timed(struct event_context *ev, TALLOC_CTX } /* - a timer has gone off - call it + do a single event loop using the events defined in ev + + return the delay untill the next timed event, + or zero if a timed event was triggered */ -void common_event_loop_timer(struct event_context *ev) +struct timeval common_event_loop_timer_delay(struct event_context *ev) { - struct timeval t = timeval_current(); + struct timeval current_time = timeval_zero(); struct timed_event *te = ev->timed_events; - if (te == NULL) { - return; + if (!te) { + /* have a default tick time of 30 seconds. This guarantees + that code that uses its own timeout checking will be + able to proceeed eventually */ + return timeval_set(30, 0); } + /* + * work out the right timeout for the next timed event + * + * avoid the syscall to gettimeofday() if the timed event should + * be triggered directly + * + * if there's a delay till the next timed event, we're done + * with just returning the delay + */ + if (!timeval_is_zero(&te->next_event)) { + struct timeval delay; + + current_time = timeval_current(); + + delay = timeval_until(¤t_time, &te->next_event); + if (!timeval_is_zero(&delay)) { + return delay; + } + } + + /* + * ok, we have a timed event that we'll process ... + */ + /* deny the handler to free the event */ talloc_set_destructor(te, common_event_timed_deny_destructor); @@ -104,33 +132,21 @@ void common_event_loop_timer(struct event_context *ev) * handler we don't want to come across this event again -- vl */ DLIST_REMOVE(ev->timed_events, te); - te->handler(ev, te, t, te->private_data); + /* + * If the timed event was registered for a zero current_time, + * then we pass a zero timeval here too! To avoid the + * overhead of gettimeofday() calls. + * + * otherwise we pass the current time + */ + te->handler(ev, te, current_time, te->private_data); /* The destructor isn't necessary anymore, we've already removed the * event from the list. */ talloc_set_destructor(te, NULL); talloc_free(te); -} -/* - do a single event loop using the events defined in ev -*/ -struct timeval common_event_loop_delay(struct event_context *ev) -{ - struct timeval tval; - - /* work out the right timeout for all timed events */ - if (ev->timed_events) { - struct timeval t = timeval_current(); - tval = timeval_until(&t, &ev->timed_events->next_event); - } else { - /* have a default tick time of 30 seconds. This guarantees - that code that uses its own timeout checking will be - able to proceeed eventually */ - tval = timeval_set(30, 0); - } - - return tval; + return timeval_zero(); } -- cgit