spa_config: Rename spa_config_enter_mmp() to spa_config_enter_priority()

Originally this was created for MMP, but now new cases are emerging
where the same mechanism is required. Hence the name's generalization.

Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Brian Behlendorf <[email protected]>
Reviewed-by: Allan Jude <[email protected]>
Reviewed-by: Igor Kozhukhov <[email protected]>
Signed-off-by: Igor Ostapenko <[email protected]>
Closes #17793

Author: ihoro

include/sys/spa.h

@@ -1030,7 +1030,7 @@ extern void spa_import_progress_set_notes_nolog(spa_t *spa,
 extern int spa_config_tryenter(spa_t *spa, int locks, const void *tag,
     krw_t rw);
 extern void spa_config_enter(spa_t *spa, int locks, const void *tag, krw_t rw);
-extern void spa_config_enter_mmp(spa_t *spa, int locks, const void *tag,
+extern void spa_config_enter_priority(spa_t *spa, int locks, const void *tag,
     krw_t rw);
 extern void spa_config_exit(spa_t *spa, int locks, const void *tag);
 extern int spa_config_held(spa_t *spa, int locks, krw_t rw);

module/zfs/mmp.c

@@ -446,7 +446,7 @@ mmp_write_uberblock(spa_t *spa)
 	uint64_t offset;
 
 	hrtime_t lock_acquire_time = gethrtime();
-	spa_config_enter_mmp(spa, SCL_STATE, mmp_tag, RW_READER);
+	spa_config_enter_priority(spa, SCL_STATE, mmp_tag, RW_READER);
 	lock_acquire_time = gethrtime() - lock_acquire_time;
 	if (lock_acquire_time > (MSEC2NSEC(MMP_MIN_INTERVAL) / 10))
 		zfs_dbgmsg("MMP SCL_STATE acquisition pool '%s' took %llu ns "

module/zfs/spa_misc.c

@@ -510,7 +510,7 @@ spa_config_tryenter(spa_t *spa, int locks, const void *tag, krw_t rw)
 
 static void
 spa_config_enter_impl(spa_t *spa, int locks, const void *tag, krw_t rw,
-    int mmp_flag)
+    int priority_flag)
 {
 	(void) tag;
 	int wlocks_held = 0;
@@ -526,7 +526,7 @@ spa_config_enter_impl(spa_t *spa, int locks, const void *tag, krw_t rw,
 		mutex_enter(&scl->scl_lock);
 		if (rw == RW_READER) {
 			while (scl->scl_writer ||
-			    (!mmp_flag && scl->scl_write_wanted)) {
+			    (!priority_flag && scl->scl_write_wanted)) {
 				cv_wait(&scl->scl_cv, &scl->scl_lock);
 			}
 		} else {
@@ -551,7 +551,7 @@ spa_config_enter(spa_t *spa, int locks, const void *tag, krw_t rw)
 }
 
 /*
- * The spa_config_enter_mmp() allows the mmp thread to cut in front of
+ * The spa_config_enter_priority() allows the mmp thread to cut in front of
  * outstanding write lock requests. This is needed since the mmp updates are
  * time sensitive and failure to service them promptly will result in a
  * suspended pool. This pool suspension has been seen in practice when there is
@@ -560,7 +560,7 @@ spa_config_enter(spa_t *spa, int locks, const void *tag, krw_t rw)
  */
 
 void
-spa_config_enter_mmp(spa_t *spa, int locks, const void *tag, krw_t rw)
+spa_config_enter_priority(spa_t *spa, int locks, const void *tag, krw_t rw)
 {
 	spa_config_enter_impl(spa, locks, tag, rw, 1);
 }