[dm-devel] [PATCH v2 38/48] multipathd: pass in the type of reconfigure
mwilck at suse.com
mwilck at suse.com
Thu Nov 18 22:58:30 UTC 2021
From: Benjamin Marzinski <bmarzins at redhat.com>
schedule_reconfigure() now takes the type of reconfigure to do, and that
gets passed down to reconfigure(). If a full reconfigure has already
been requested but not started, weak reconfigure requests will be
upgraded. Currently cli_reconfigure() and the HUP signal request full
reconfigures, while the initial reconfigure, ev_add_map(), and
missing_uev_wait_tick() request weak reconfigures. A future patch will
enable users to control what kind of reconfigures happen.
Signed-off-by: Benjamin Marzinski <bmarzins at redhat.com>
Reviewed-by: Martin Wilck <mwilck at suse.com>
Signed-off-by: Martin Wilck <mwilck at suse.com>
---
libmultipath/configure.c | 2 +-
multipathd/cli_handlers.c | 2 +-
multipathd/main.c | 55 +++++++++++++++++++++------------------
multipathd/main.h | 2 +-
4 files changed, 32 insertions(+), 29 deletions(-)
diff --git a/libmultipath/configure.c b/libmultipath/configure.c
index 7edb355..eb8ec1b 100644
--- a/libmultipath/configure.c
+++ b/libmultipath/configure.c
@@ -1098,7 +1098,7 @@ out:
* FORCE_RELOAD_NONE: existing maps aren't touched at all
* FORCE_RELOAD_YES: all maps are rebuilt from scratch and (re)loaded in DM
* FORCE_RELOAD_WEAK: existing maps are compared to the current conf and only
- * reloaded in DM if there's a difference. This is useful during startup.
+ * reloaded in DM if there's a difference. This is normally sufficient.
*/
int coalesce_paths (struct vectors *vecs, vector mpvec, char *refwwid,
int force_reload, enum mpath_cmds cmd)
diff --git a/multipathd/cli_handlers.c b/multipathd/cli_handlers.c
index f59db3a..d165675 100644
--- a/multipathd/cli_handlers.c
+++ b/multipathd/cli_handlers.c
@@ -1012,7 +1012,7 @@ cli_reconfigure(void * v, struct strbuf *reply, void * data)
{
condlog(2, "reconfigure (operator)");
- schedule_reconfigure();
+ schedule_reconfigure(FORCE_RELOAD_YES);
return 0;
}
diff --git a/multipathd/main.c b/multipathd/main.c
index 57c572d..1efbaab 100644
--- a/multipathd/main.c
+++ b/multipathd/main.c
@@ -162,13 +162,6 @@ static bool get_delayed_reconfig(void)
return val;
}
-static void set_delayed_reconfig(bool val)
-{
- pthread_mutex_lock(&config_lock);
- __delayed_reconfig = val;
- pthread_mutex_unlock(&config_lock);
-}
-
/*
* global copy of vecs for use in sig handlers
*/
@@ -290,7 +283,18 @@ enum daemon_status wait_for_state_change_if(enum daemon_status oldstate,
}
/* Don't access this variable without holding config_lock */
-static bool reconfigure_pending;
+static enum force_reload_types reconfigure_pending = FORCE_RELOAD_NONE;
+/* Only set while changing to DAEMON_CONFIGURE, and only access while
+ * reconfiguring or scheduling a delayed reconfig in DAEMON_CONFIGURE */
+static volatile enum force_reload_types reload_type = FORCE_RELOAD_NONE;
+
+static void enable_delayed_reconfig(void)
+{
+ pthread_mutex_lock(&config_lock);
+ reconfigure_pending = reload_type;
+ __delayed_reconfig = true;
+ pthread_mutex_unlock(&config_lock);
+}
/* must be called with config_lock held */
static void __post_config_state(enum daemon_status state)
@@ -305,7 +309,8 @@ static void __post_config_state(enum daemon_status state)
* In either case, child() will see DAEMON_CONFIGURE
* again and start another reconfigure cycle.
*/
- if (reconfigure_pending && state == DAEMON_IDLE &&
+ if (reconfigure_pending != FORCE_RELOAD_NONE &&
+ state == DAEMON_IDLE &&
(old_state == DAEMON_CONFIGURE ||
old_state == DAEMON_RUNNING)) {
/*
@@ -317,7 +322,8 @@ static void __post_config_state(enum daemon_status state)
state = DAEMON_CONFIGURE;
}
if (state == DAEMON_CONFIGURE) {
- reconfigure_pending = false;
+ reload_type = (reconfigure_pending == FORCE_RELOAD_YES) ? FORCE_RELOAD_YES : FORCE_RELOAD_WEAK;
+ reconfigure_pending = FORCE_RELOAD_NONE;
__delayed_reconfig = false;
}
running_state = state;
@@ -334,20 +340,26 @@ void post_config_state(enum daemon_status state)
pthread_cleanup_pop(1);
}
-void schedule_reconfigure(void)
+void schedule_reconfigure(enum force_reload_types requested_type)
{
pthread_mutex_lock(&config_lock);
pthread_cleanup_push(config_cleanup, NULL);
+ enum force_reload_types type;
+
+ type = (reconfigure_pending == FORCE_RELOAD_YES ||
+ requested_type == FORCE_RELOAD_YES) ?
+ FORCE_RELOAD_YES : FORCE_RELOAD_WEAK;
switch (running_state)
{
case DAEMON_SHUTDOWN:
break;
case DAEMON_IDLE:
+ reconfigure_pending = type;
__post_config_state(DAEMON_CONFIGURE);
break;
case DAEMON_CONFIGURE:
case DAEMON_RUNNING:
- reconfigure_pending = true;
+ reconfigure_pending = type;
break;
default:
break;
@@ -812,7 +824,7 @@ ev_add_map (char * dev, const char * alias, struct vectors * vecs)
if (get_delayed_reconfig() &&
!need_to_delay_reconfig(vecs)) {
condlog(2, "reconfigure (delayed)");
- schedule_reconfigure();
+ schedule_reconfigure(FORCE_RELOAD_WEAK);
return 0;
}
}
@@ -1830,7 +1842,7 @@ missing_uev_wait_tick(struct vectors *vecs)
if (timed_out && get_delayed_reconfig() &&
!need_to_delay_reconfig(vecs)) {
condlog(2, "reconfigure (delayed)");
- schedule_reconfigure();
+ schedule_reconfigure(FORCE_RELOAD_WEAK);
}
}
@@ -2595,7 +2607,6 @@ configure (struct vectors * vecs)
vector mpvec;
int i, ret;
struct config *conf;
- static int force_reload = FORCE_RELOAD_WEAK;
if (!vecs->pathvec && !(vecs->pathvec = vector_alloc())) {
condlog(0, "couldn't allocate path vec in configure");
@@ -2643,15 +2654,7 @@ configure (struct vectors * vecs)
if (should_exit())
goto fail;
- /*
- * create new set of maps & push changed ones into dm
- * In the first call, use FORCE_RELOAD_WEAK to avoid making
- * superfluous ACT_RELOAD ioctls. Later calls are done
- * with FORCE_RELOAD_YES.
- */
- ret = coalesce_paths(vecs, mpvec, NULL, force_reload, CMD_NONE);
- if (force_reload == FORCE_RELOAD_WEAK)
- force_reload = FORCE_RELOAD_YES;
+ ret = coalesce_paths(vecs, mpvec, NULL, reload_type, CMD_NONE);
if (ret != CP_OK) {
condlog(0, "configure failed while coalescing paths");
goto fail;
@@ -2815,7 +2818,7 @@ handle_signals(bool nonfatal)
return;
if (reconfig_sig) {
condlog(2, "reconfigure (signal)");
- schedule_reconfigure();
+ schedule_reconfigure(FORCE_RELOAD_YES);
}
if (log_reset_sig) {
condlog(2, "reset log (signal)");
@@ -3276,7 +3279,7 @@ child (__attribute__((unused)) void *param)
if (!need_to_delay_reconfig(vecs))
reconfigure(vecs);
else
- set_delayed_reconfig(true);
+ enable_delayed_reconfig();
lock_cleanup_pop(vecs->lock);
post_config_state(DAEMON_IDLE);
}
diff --git a/multipathd/main.h b/multipathd/main.h
index 7017380..c91f9f9 100644
--- a/multipathd/main.h
+++ b/multipathd/main.h
@@ -37,7 +37,7 @@ void exit_daemon(void);
const char * daemon_status(void);
enum daemon_status wait_for_state_change_if(enum daemon_status oldstate,
unsigned long ms);
-void schedule_reconfigure(void);
+void schedule_reconfigure(enum force_reload_types requested_type);
int need_to_delay_reconfig (struct vectors *);
int ev_add_path (struct path *, struct vectors *, int);
int ev_remove_path (struct path *, struct vectors *, int);
--
2.33.1
More information about the dm-devel
mailing list