| Message ID | 20211118225840.19810-34-mwilck@suse.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Delegated to: | christophe varoqui |
| Headers | show |
| Series | multipathd: uxlsnr overhaul | expand |
On Thu, Nov 18, 2021 at 11:58:25PM +0100, mwilck@suse.com wrote: > From: Martin Wilck <mwilck@suse.com> > > The list of clients is never changed anywhere except in > uxsock_listen(). No need to lock. > > Signed-off-by: Martin Wilck <mwilck@suse.com> Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com> > --- > multipathd/uxlsnr.c | 33 ++++++--------------------------- > 1 file changed, 6 insertions(+), 27 deletions(-) > > diff --git a/multipathd/uxlsnr.c b/multipathd/uxlsnr.c > index 6213454..24db377 100644 > --- a/multipathd/uxlsnr.c > +++ b/multipathd/uxlsnr.c > @@ -89,7 +89,6 @@ enum { > static __attribute__((unused)) char ___a[-(MIN_POLLS <= 0)]; > > static LIST_HEAD(clients); > -static pthread_mutex_t client_lock = PTHREAD_MUTEX_INITIALIZER; > static struct pollfd *polls; > static int notify_fd = -1; > static int idle_fd = -1; > @@ -136,15 +135,13 @@ static void new_client(int ux_sock) > c->is_root = _socket_client_is_root(c->fd); > > /* put it in our linked list */ > - pthread_mutex_lock(&client_lock); > list_add_tail(&c->node, &clients); > - pthread_mutex_unlock(&client_lock); > } > > /* > * kill off a dead client > */ > -static void _dead_client(struct client *c) > +static void dead_client(struct client *c) > { > int fd = c->fd; > list_del_init(&c->node); > @@ -156,14 +153,6 @@ static void _dead_client(struct client *c) > close(fd); > } > > -static void dead_client(struct client *c) > -{ > - pthread_cleanup_push(cleanup_mutex, &client_lock); > - pthread_mutex_lock(&client_lock); > - _dead_client(c); > - pthread_cleanup_pop(1); > -} > - > static void free_polls (void) > { > if (polls) > @@ -180,11 +169,9 @@ void uxsock_cleanup(void *arg) > close(notify_fd); > free(watch_config_dir); > > - pthread_mutex_lock(&client_lock); > list_for_each_entry_safe(client_loop, client_tmp, &clients, node) { > - _dead_client(client_loop); > + dead_client(client_loop); > } > - pthread_mutex_unlock(&client_lock); > > cli_exit(); > free_polls(); > @@ -308,8 +295,7 @@ 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) > +static struct timespec *get_soonest_timeout(struct timespec *ts) > { > struct timespec ts_min = ts_max, now; > bool any = false; > @@ -336,8 +322,7 @@ static struct timespec *__get_soonest_timeout(struct timespec *ts) > return ts; > } > > -/* call with clients lock held */ > -static bool __need_vecs_lock(void) > +static bool need_vecs_lock(void) > { > struct client *c; > > @@ -614,7 +599,6 @@ void *uxsock_listen(long ux_sock, void *trigger_data) > /* conf->sequence_nr will be 1 when uxsock_listen is first called */ > unsigned int sequence_nr = 0; > struct watch_descriptors wds = { .conf_wd = -1, .dir_wd = -1 }; > - bool need_lock = false; > struct vectors *vecs = trigger_data; > > condlog(3, "uxsock: startup listener"); > @@ -645,8 +629,6 @@ void *uxsock_listen(long ux_sock, void *trigger_data) > struct timespec __timeout, *timeout; > > /* setup for a poll */ > - pthread_mutex_lock(&client_lock); > - pthread_cleanup_push(cleanup_mutex, &client_lock); > num_clients = 0; > list_for_each_entry(c, &clients, node) { > num_clients++; > @@ -686,9 +668,8 @@ void *uxsock_listen(long ux_sock, void *trigger_data) > else > polls[POLLFD_NOTIFY].events = POLLIN; > > - need_lock = __need_vecs_lock(); > polls[POLLFD_IDLE].fd = idle_fd; > - if (need_lock) > + if (need_vecs_lock()) > polls[POLLFD_IDLE].events = POLLIN; > else > polls[POLLFD_IDLE].events = 0; > @@ -713,9 +694,7 @@ void *uxsock_listen(long ux_sock, void *trigger_data) > break; > } > n_pfds = i; > - timeout = __get_soonest_timeout(&__timeout); > - > - pthread_cleanup_pop(1); > + timeout = get_soonest_timeout(&__timeout); > > /* most of our life is spent in this call */ > poll_count = ppoll(polls, n_pfds, timeout, &mask); > -- > 2.33.1 -- dm-devel mailing list dm-devel@redhat.com https://listman.redhat.com/mailman/listinfo/dm-devel
diff --git a/multipathd/uxlsnr.c b/multipathd/uxlsnr.c index 6213454..24db377 100644 --- a/multipathd/uxlsnr.c +++ b/multipathd/uxlsnr.c @@ -89,7 +89,6 @@ enum { static __attribute__((unused)) char ___a[-(MIN_POLLS <= 0)]; static LIST_HEAD(clients); -static pthread_mutex_t client_lock = PTHREAD_MUTEX_INITIALIZER; static struct pollfd *polls; static int notify_fd = -1; static int idle_fd = -1; @@ -136,15 +135,13 @@ static void new_client(int ux_sock) c->is_root = _socket_client_is_root(c->fd); /* put it in our linked list */ - pthread_mutex_lock(&client_lock); list_add_tail(&c->node, &clients); - pthread_mutex_unlock(&client_lock); } /* * kill off a dead client */ -static void _dead_client(struct client *c) +static void dead_client(struct client *c) { int fd = c->fd; list_del_init(&c->node); @@ -156,14 +153,6 @@ static void _dead_client(struct client *c) close(fd); } -static void dead_client(struct client *c) -{ - pthread_cleanup_push(cleanup_mutex, &client_lock); - pthread_mutex_lock(&client_lock); - _dead_client(c); - pthread_cleanup_pop(1); -} - static void free_polls (void) { if (polls) @@ -180,11 +169,9 @@ void uxsock_cleanup(void *arg) close(notify_fd); free(watch_config_dir); - pthread_mutex_lock(&client_lock); list_for_each_entry_safe(client_loop, client_tmp, &clients, node) { - _dead_client(client_loop); + dead_client(client_loop); } - pthread_mutex_unlock(&client_lock); cli_exit(); free_polls(); @@ -308,8 +295,7 @@ 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) +static struct timespec *get_soonest_timeout(struct timespec *ts) { struct timespec ts_min = ts_max, now; bool any = false; @@ -336,8 +322,7 @@ static struct timespec *__get_soonest_timeout(struct timespec *ts) return ts; } -/* call with clients lock held */ -static bool __need_vecs_lock(void) +static bool need_vecs_lock(void) { struct client *c; @@ -614,7 +599,6 @@ void *uxsock_listen(long ux_sock, void *trigger_data) /* conf->sequence_nr will be 1 when uxsock_listen is first called */ unsigned int sequence_nr = 0; struct watch_descriptors wds = { .conf_wd = -1, .dir_wd = -1 }; - bool need_lock = false; struct vectors *vecs = trigger_data; condlog(3, "uxsock: startup listener"); @@ -645,8 +629,6 @@ void *uxsock_listen(long ux_sock, void *trigger_data) struct timespec __timeout, *timeout; /* setup for a poll */ - pthread_mutex_lock(&client_lock); - pthread_cleanup_push(cleanup_mutex, &client_lock); num_clients = 0; list_for_each_entry(c, &clients, node) { num_clients++; @@ -686,9 +668,8 @@ void *uxsock_listen(long ux_sock, void *trigger_data) else polls[POLLFD_NOTIFY].events = POLLIN; - need_lock = __need_vecs_lock(); polls[POLLFD_IDLE].fd = idle_fd; - if (need_lock) + if (need_vecs_lock()) polls[POLLFD_IDLE].events = POLLIN; else polls[POLLFD_IDLE].events = 0; @@ -713,9 +694,7 @@ void *uxsock_listen(long ux_sock, void *trigger_data) break; } n_pfds = i; - timeout = __get_soonest_timeout(&__timeout); - - pthread_cleanup_pop(1); + timeout = get_soonest_timeout(&__timeout); /* most of our life is spent in this call */ poll_count = ppoll(polls, n_pfds, timeout, &mask);