svn commit: r355725 - in head/sys: kern sys

[John Baldwin]

Author: jhb
Date: Fri Dec 13 19:26:04 2019
New Revision: 355725
URL: https://svnweb.freebsd.org/changeset/base/355725

Log:
  Use callout(9) instead of deprecated timeout(9) for fail points.
  
  Allocate the callout structure on-demand from
  fail_point_use_timeout_path() since most fail points do not use
  timeouts.
  
  Reviewed by:	markj (earlier version), cem
  Differential Revision:	https://reviews.freebsd.org/D22599

Modified:
  head/sys/kern/kern_fail.c
  head/sys/sys/fail.h

Modified: head/sys/kern/kern_fail.c
==============================================================================
--- head/sys/kern/kern_fail.c	Fri Dec 13 19:21:58 2019	(r355724)
+++ head/sys/kern/kern_fail.c	Fri Dec 13 19:26:04 2019	(r355725)
@@ -403,6 +403,8 @@ fail_point_drain(struct fail_point *fp, int expected_r
 		wakeup(FP_PAUSE_CHANNEL(fp));
 		tsleep(&fp, PWAIT, "fail_point_drain", hz / 100);
 	}
+	if (fp->fp_callout)
+		callout_drain(fp->fp_callout);
 	fail_point_swap_settings(fp, entries);
 }
 
@@ -442,8 +444,8 @@ fail_point_sleep(struct fail_point *fp, int msecs,
 			if (fp->fp_pre_sleep_fn)
 				fp->fp_pre_sleep_fn(fp->fp_pre_sleep_arg);
 
-			timeout(fp->fp_post_sleep_fn, fp->fp_post_sleep_arg,
-			    timo);
+			callout_reset(fp->fp_callout, timo,
+			    fp->fp_post_sleep_fn, fp->fp_post_sleep_arg);
 			*pret = FAIL_POINT_RC_QUEUED;
 		}
 	}
@@ -493,6 +495,20 @@ fail_point_init(struct fail_point *fp, const char *fmt
 	fp->fp_post_sleep_arg = NULL;
 }
 
+void
+fail_point_alloc_callout(struct fail_point *fp)
+{
+
+	/**
+	 * This assumes that calls to fail_point_use_timeout_path()
+	 * will not race.
+	 */
+	if (fp->fp_callout != NULL)
+		return;
+	fp->fp_callout = fp_malloc(sizeof(*fp->fp_callout), M_WAITOK);
+	callout_init(fp->fp_callout, CALLOUT_MPSAFE);
+}
+
 /**
  * Free the resources held by a fail_point, and wake any paused threads.
  * Thou shalt not allow threads to hit this fail point after you enter this
@@ -510,6 +526,10 @@ fail_point_destroy(struct fail_point *fp)
 		fp->fp_name = NULL;
 	}
 	fp->fp_flags = 0;
+	if (fp->fp_callout) {
+		fp_free(fp->fp_callout);
+		fp->fp_callout = NULL;
+	}
 
 	sx_xlock(&sx_fp_set);
 	fail_point_garbage_collect();

Modified: head/sys/sys/fail.h
==============================================================================
--- head/sys/sys/fail.h	Fri Dec 13 19:21:58 2019	(r355724)
+++ head/sys/sys/fail.h	Fri Dec 13 19:26:04 2019	(r355725)
@@ -84,6 +84,8 @@ struct fail_point {
 	void (*fp_post_sleep_fn)(void *);
 	/**< Arg for fp_post_sleep_fn */
 	void *fp_post_sleep_arg;
+
+	struct callout *fp_callout;
 };
 
 #define	FAIL_POINT_DYNAMIC_NAME	0x01	/**< Must free name on destroy */
@@ -149,9 +151,12 @@ fail_point_sleep_set_post_arg(struct fail_point *fp, v
 {
 	fp->fp_post_sleep_arg = sleep_arg;
 }
+
+void fail_point_alloc_callout(struct fail_point *);
+
 /**
  * If the FAIL_POINT_USE_TIMEOUT flag is set on a failpoint, then
- * FAIL_POINT_SLEEP will result in a call to timeout instead of
+ * FAIL_POINT_SLEEP will result in a call to callout_reset instead of
  * msleep. Note that if you sleep while this flag is set, you must
  * set fp_post_sleep_fn or an error will occur upon waking.
  */
@@ -163,9 +168,10 @@ fail_point_use_timeout_path(struct fail_point *fp, boo
 	        (post_sleep_fn == NULL && fp->fp_post_sleep_fn != NULL),
 	        ("Setting fp to use timeout, but not setting post_sleep_fn\n"));
 
-	if (use_timeout)
+	if (use_timeout) {
+		fail_point_alloc_callout(fp);
 		fp->fp_flags |= FAIL_POINT_USE_TIMEOUT_PATH;
-	else
+	} else
 		fp->fp_flags &= ~FAIL_POINT_USE_TIMEOUT_PATH;
 
 	if (post_sleep_fn != NULL)