Improve uxlsnr by adding a lock around the poll structure and
not reallocating memory for every poll, thereby significantly
speedup processing.
Signed-off-by: Hannes Reinecke <hare@xxxxxxxx>
---
multipathd/main.c | 6 ++--
multipathd/uxlsnr.c | 84 +++++++++++++++++++++++++++++++----------------------
2 files changed, 53 insertions(+), 37 deletions(-)
diff --git a/multipathd/main.c b/multipathd/main.c
index 61b82f6..c1b94bd 100644
--- a/multipathd/main.c
+++ b/multipathd/main.c
@@ -966,8 +966,10 @@ uevqloop (void * ap)
static void *
uxlsnrloop (void * ap)
{
- if (cli_init())
+ if (cli_init()) {
+ condlog(1, "Failed to init uxsock listener");
return NULL;
+ }
set_handler_callback(LIST+PATHS, cli_list_paths);
set_handler_callback(LIST+PATHS+FMT, cli_list_paths_fmt);
@@ -1278,7 +1280,7 @@ check_path (struct vectors * vecs, struct path * pp)
sysfs_attr_set_value(pp->udev, "uevent", "change",
strlen("change"));
return 0;
- }
+ }
/*
* provision a next check soonest,
diff --git a/multipathd/uxlsnr.c b/multipathd/uxlsnr.c
index e5c5d90..77efa8a 100644
--- a/multipathd/uxlsnr.c
+++ b/multipathd/uxlsnr.c
@@ -44,6 +44,8 @@ struct client {
int fd;
};
+#define MIN_POLLS 1023
+
LIST_HEAD(clients);
pthread_mutex_t client_lock = PTHREAD_MUTEX_INITIALIZER;
struct pollfd *polls;
@@ -133,6 +135,7 @@ void * uxsock_listen(uxsock_trigger_fn uxsock_trigger, void * trigger_data)
char *inbuf;
char *reply;
sigset_t mask;
+ int old_clients = MIN_POLLS;
ux_sock = ux_socket_listen(DEFAULT_SOCKET);
@@ -142,20 +145,22 @@ void * uxsock_listen(uxsock_trigger_fn uxsock_trigger, void * trigger_data)
}
if (!conf) {
- condlog(1, "configuration changed");
+ condlog(1, "uxsock: configuration changed");
return NULL;
}
- timeout = conf->uxsock_timeout;
-
pthread_cleanup_push(uxsock_cleanup, NULL);
- polls = (struct pollfd *)MALLOC(0);
+ condlog(3, "uxsock: startup listener");
+ polls = (struct pollfd *)MALLOC(MIN_POLLS + 1);
+ if (!polls) {
+ condlog(0, "uxsock: failed to allocate poll fds");
+ return NULL;
+ }
pthread_sigmask(SIG_SETMASK, NULL, &mask);
sigdelset(&mask, SIGHUP);
sigdelset(&mask, SIGUSR1);
while (1) {
- struct pollfd *new;
struct client *c, *tmp;
int i, poll_count, num_clients;
@@ -173,19 +178,25 @@ void * uxsock_listen(uxsock_trigger_fn uxsock_trigger, void * trigger_data)
list_for_each_entry(c, &clients, node) {
num_clients++;
}
- new = REALLOC(polls, (1+num_clients) * sizeof(*polls));
- /* If we can't allocate poliing space for the new client,
- * close it */
- if (!new) {
- if (!num_clients) {
- condlog(1, "can't listen for new clients");
- return NULL;
+ if (num_clients != old_clients) {
+ struct pollfd *new;
+ if (num_clients < MIN_POLLS) {
+ new = REALLOC(polls, (1 + MIN_POLLS) *
+ sizeof(struct pollfd));
+ } else {
+ new = REALLOC(polls, (1+num_clients) *
+ sizeof(struct pollfd));
}
- dead_client(list_entry(clients.prev,
- typeof(struct client), node));
- }
- else
+ if (!new) {
+ pthread_mutex_unlock(&client_lock);
+ condlog(0, "%s: failed to realloc %d poll fds",
+ "uxsock", 1 + num_clients);
+ pthread_yield();
+ continue;
+ }
+ num_clients = old_clients;
polls = new;
+ }
polls[0].fd = ux_sock;
polls[0].events = POLLIN;
@@ -208,8 +219,8 @@ void * uxsock_listen(uxsock_trigger_fn uxsock_trigger, void * trigger_data)
}
/* something went badly wrong! */
- condlog(0, "poll");
- pthread_exit(NULL);
+ condlog(0, "uxsock: poll failed with %d", errno);
+ break;
}
if (poll_count == 0)
@@ -230,7 +241,7 @@ void * uxsock_listen(uxsock_trigger_fn uxsock_trigger, void * trigger_data)
}
pthread_mutex_unlock(&client_lock);
if (!c) {
- condlog(3, "cli%d: invalid fd %d",
+ condlog(4, "cli%d: new fd %d",
i, polls[i].fd);
continue;
}
@@ -238,24 +249,27 @@ void * uxsock_listen(uxsock_trigger_fn uxsock_trigger, void * trigger_data)
start_time.tv_sec = 0;
if (recv_packet(c->fd, &inbuf, timeout) != 0) {
dead_client(c);
- } else {
- condlog(4, "Got request [%s]", inbuf);
- uxsock_trigger(inbuf, &reply, &rlen,
- trigger_data);
- if (reply) {
- if (send_packet(c->fd,
- reply) != 0) {
- dead_client(c);
- }
- condlog(4, "Reply [%d bytes]",
- rlen);
- FREE(reply);
- reply = NULL;
+ continue;
+ }
+ condlog(4, "cli[%d]: Got request [%s]",
+ i, inbuf);
+ uxsock_trigger(inbuf, &reply, &rlen,
+ trigger_data);
+ if (reply) {
+ if (send_packet(c->fd,
+ reply) != 0) {
+ dead_client(c);
+ } else {
+ condlog(4, "cli[%d]: "
+ "Reply [%d bytes]",
+ i, rlen);
}
- check_timeout(start_time, inbuf,
- timeout);
- FREE(inbuf);
+ FREE(reply);
+ reply = NULL;
}
+ check_timeout(start_time, inbuf,
+ timeout);
+ FREE(inbuf);
}
}
--
2.6.6
--
dm-devel mailing list
dm-devel@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/dm-devel
