From 10146c9c51e17272970b19434be2e0bca0c7cf8f Mon Sep 17 00:00:00 2001 From: Willy Tarreau Date: Mon, 13 Apr 2015 20:44:19 +0200 Subject: [PATCH] CLEANUP: poll: move the conditions for waiting out of the poll functions The poll() functions have become a bit dirty because they now check the size of the signal queue, the FD cache and the number of tasks. It's not their job, this must be moved to the caller. In the end it simplifies the code because the expiration date is now set to now_ms if we must not wait, and this achieves in exactly the same result and is cleaner. The change looks large due to the change of indent for blocks which were inside an "if" block. --- src/ev_epoll.c | 24 +++++------------------- src/ev_kqueue.c | 27 ++++++++++++--------------- src/ev_poll.c | 6 +----- src/ev_select.c | 26 +++++++++++--------------- src/haproxy.c | 4 ++++ 5 files changed, 33 insertions(+), 54 deletions(-) diff --git a/src/ev_epoll.c b/src/ev_epoll.c index c52d07521..ccb7c3377 100644 --- a/src/ev_epoll.c +++ b/src/ev_epoll.c @@ -25,9 +25,6 @@ #include #include -#include -#include - /* private data */ @@ -112,25 +109,14 @@ REGPRM2 static void _do_poll(struct poller *p, int exp) fd_nbupdt = 0; /* compute the epoll_wait() timeout */ - - if (fd_cache_num || run_queue || signal_queue_len) { - /* Maybe we still have events in the spec list, or there are - * some tasks left pending in the run_queue, so we must not - * wait in epoll() otherwise we would delay their delivery by - * the next timeout. - */ + if (!exp) + wait_time = MAX_DELAY_MS; + else if (tick_is_expired(exp, now_ms)) wait_time = 0; - } else { - if (!exp) + wait_time = TICKS_TO_MS(tick_remain(now_ms, exp)) + 1; + if (wait_time > MAX_DELAY_MS) wait_time = MAX_DELAY_MS; - else if (tick_is_expired(exp, now_ms)) - wait_time = 0; - else { - wait_time = TICKS_TO_MS(tick_remain(now_ms, exp)) + 1; - if (wait_time > MAX_DELAY_MS) - wait_time = MAX_DELAY_MS; - } } /* now let's wait for polled events */ diff --git a/src/ev_kqueue.c b/src/ev_kqueue.c index 2af94b647..007336fa7 100644 --- a/src/ev_kqueue.c +++ b/src/ev_kqueue.c @@ -26,8 +26,7 @@ #include #include -#include -#include + /* private data */ static int kqueue_fd; @@ -93,19 +92,17 @@ REGPRM2 static void _do_poll(struct poller *p, int exp) timeout.tv_sec = 0; timeout.tv_nsec = 0; - if (!fd_cache_num && !run_queue && !signal_queue_len) { - if (!exp) { - delta_ms = MAX_DELAY_MS; - timeout.tv_sec = (MAX_DELAY_MS / 1000); - timeout.tv_nsec = (MAX_DELAY_MS % 1000) * 1000000; - } - else if (!tick_is_expired(exp, now_ms)) { - delta_ms = TICKS_TO_MS(tick_remain(now_ms, exp)) + 1; - if (delta_ms > MAX_DELAY_MS) - delta_ms = MAX_DELAY_MS; - timeout.tv_sec = (delta_ms / 1000); - timeout.tv_nsec = (delta_ms % 1000) * 1000000; - } + if (!exp) { + delta_ms = MAX_DELAY_MS; + timeout.tv_sec = (MAX_DELAY_MS / 1000); + timeout.tv_nsec = (MAX_DELAY_MS % 1000) * 1000000; + } + else if (!tick_is_expired(exp, now_ms)) { + delta_ms = TICKS_TO_MS(tick_remain(now_ms, exp)) + 1; + if (delta_ms > MAX_DELAY_MS) + delta_ms = MAX_DELAY_MS; + timeout.tv_sec = (delta_ms / 1000); + timeout.tv_nsec = (delta_ms % 1000) * 1000000; } fd = MIN(maxfd, global.tune.maxpollevents); diff --git a/src/ev_poll.c b/src/ev_poll.c index 866906c3a..44a2b9b64 100644 --- a/src/ev_poll.c +++ b/src/ev_poll.c @@ -23,8 +23,6 @@ #include #include -#include -#include static unsigned int *fd_evts[2]; @@ -116,9 +114,7 @@ REGPRM2 static void _do_poll(struct poller *p, int exp) } /* now let's wait for events */ - if (fd_cache_num || run_queue || signal_queue_len) - wait_time = 0; - else if (!exp) + if (!exp) wait_time = MAX_DELAY_MS; else if (tick_is_expired(exp, now_ms)) wait_time = 0; diff --git a/src/ev_select.c b/src/ev_select.c index 73fe327aa..35d3c77db 100644 --- a/src/ev_select.c +++ b/src/ev_select.c @@ -22,8 +22,6 @@ #include #include -#include -#include static fd_set *fd_evts[2]; @@ -83,19 +81,17 @@ REGPRM2 static void _do_poll(struct poller *p, int exp) delta.tv_sec = 0; delta.tv_usec = 0; - if (!fd_cache_num && !run_queue && !signal_queue_len) { - if (!exp) { - delta_ms = MAX_DELAY_MS; - delta.tv_sec = (MAX_DELAY_MS / 1000); - delta.tv_usec = (MAX_DELAY_MS % 1000) * 1000; - } - else if (!tick_is_expired(exp, now_ms)) { - delta_ms = TICKS_TO_MS(tick_remain(now_ms, exp)) + SCHEDULER_RESOLUTION; - if (delta_ms > MAX_DELAY_MS) - delta_ms = MAX_DELAY_MS; - delta.tv_sec = (delta_ms / 1000); - delta.tv_usec = (delta_ms % 1000) * 1000; - } + if (!exp) { + delta_ms = MAX_DELAY_MS; + delta.tv_sec = (MAX_DELAY_MS / 1000); + delta.tv_usec = (MAX_DELAY_MS % 1000) * 1000; + } + else if (!tick_is_expired(exp, now_ms)) { + delta_ms = TICKS_TO_MS(tick_remain(now_ms, exp)) + SCHEDULER_RESOLUTION; + if (delta_ms > MAX_DELAY_MS) + delta_ms = MAX_DELAY_MS; + delta.tv_sec = (delta_ms / 1000); + delta.tv_usec = (delta_ms % 1000) * 1000; } /* let's restore fdset state */ diff --git a/src/haproxy.c b/src/haproxy.c index b2f3e367a..752c4a2d0 100644 --- a/src/haproxy.c +++ b/src/haproxy.c @@ -1486,6 +1486,10 @@ void run_poll_loop() if (jobs == 0) break; + /* expire immediately if events are pending */ + if (fd_cache_num || run_queue || signal_queue_len) + next = now_ms; + /* The poller will ensure it returns around */ cur_poller.poll(&cur_poller, next); fd_process_cached_events();