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Similar Internal Domain=false; Similar Monitored External Domain=false; Custom External Domain=false; Mimecast External Domain=false; Newly Observed Domain=false; Internal User Name=false; Custom Display Name List=false; Reply-to Address Mismatch=false; Targeted Threat Dictionary=false; Mimecast Threat Dictionary=false; Custom Threat Dictionary=false X-Scanned-By: MIMEDefang 2.84 on 10.11.54.1 X-MIME-Autoconverted: from quoted-printable to 8bit by lists01.pubmisc.prod.ext.phx2.redhat.com id 1AIMxBPs002214 X-loop: dm-devel@redhat.com Cc: lixiaokeng@huawei.com, Chongyun Wu , dm-devel@redhat.com, Martin Wilck Subject: [dm-devel] [PATCH v2 31/48] multipathd: uxlsnr: add timeout handling X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dm-devel-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com From: Martin Wilck Our ppoll() call needs to wake up when a client request times out. This logic can be added by determining the first client that's about to time out. The logic in handle_client() will then cause a timeout reply to be sent to the client. This is more client-friendly as the client timing out without receiving a reply. Signed-off-by: Martin Wilck Reviewed-by: Benjamin Marzinski --- multipathd/uxlsnr.c | 57 +++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 52 insertions(+), 5 deletions(-) diff --git a/multipathd/uxlsnr.c b/multipathd/uxlsnr.c index bf9780d..45fe7b5 100644 --- a/multipathd/uxlsnr.c +++ b/multipathd/uxlsnr.c @@ -306,6 +306,35 @@ static void handle_inotify(int fd, struct watch_descriptors *wds) } static const struct timespec ts_zero = { .tv_sec = 0, }; +static const struct timespec ts_max = { .tv_sec = LONG_MAX, .tv_nsec = 999999999 }; + +/* call with clients lock held */ +static struct timespec *__get_soonest_timeout(struct timespec *ts) +{ + struct timespec ts_min = ts_max, now; + bool any = false; + struct client *c; + + list_for_each_entry(c, &clients, node) { + if (timespeccmp(&c->expires, &ts_zero) != 0 && + timespeccmp(&c->expires, &ts_min) < 0) { + ts_min = c->expires; + any = true; + } + } + + if (!any) + return NULL; + + get_monotonic_time(&now); + timespecsub(&ts_min, &now, ts); + if (timespeccmp(ts, &ts_zero) < 0) + *ts = ts_zero; + + condlog(4, "%s: next client expires in %ld.%03lds", __func__, + (long)ts->tv_sec, ts->tv_nsec / 1000000); + return ts; +} /* call with clients lock held */ static bool __need_vecs_lock(void) @@ -532,6 +561,24 @@ static int client_state_machine(struct client *c, struct vectors *vecs, } } +static void check_timeout(struct client *c) +{ + struct timespec now; + + if (timespeccmp(&c->expires, &ts_zero) == 0) + return; + + get_monotonic_time(&now); + if (timespeccmp(&c->expires, &now) > 0) + return; + + condlog(2, "%s: cli[%d]: timed out at %ld.%03ld", __func__, + c->fd, (long)c->expires.tv_sec, c->expires.tv_nsec / 1000000); + + c->error = -ETIMEDOUT; + set_client_state(c, CLT_SEND); +} + static void handle_client(struct client *c, struct vectors *vecs, short revents) { if (revents & (POLLHUP|POLLERR)) { @@ -539,6 +586,7 @@ static void handle_client(struct client *c, struct vectors *vecs, short revents) return; } + check_timeout(c); while (client_state_machine(c, vecs, revents) == STM_CONT); } @@ -580,6 +628,7 @@ void *uxsock_listen(long ux_sock, void *trigger_data) while (1) { struct client *c, *tmp; int i, n_pfds, poll_count, num_clients; + struct timespec __timeout, *timeout; /* setup for a poll */ pthread_mutex_lock(&client_lock); @@ -647,10 +696,12 @@ void *uxsock_listen(long ux_sock, void *trigger_data) break; } n_pfds = i; + timeout = __get_soonest_timeout(&__timeout); + pthread_cleanup_pop(1); /* most of our life is spent in this call */ - poll_count = ppoll(polls, n_pfds, NULL, &mask); + poll_count = ppoll(polls, n_pfds, timeout, &mask); handle_signals(false); if (poll_count == -1) { @@ -665,10 +716,6 @@ void *uxsock_listen(long ux_sock, void *trigger_data) break; } - if (poll_count == 0) { - handle_signals(true); - continue; - } if (polls[POLLFD_IDLE].fd != -1 && polls[POLLFD_IDLE].revents & POLLIN) drain_idle_fd(idle_fd);