Keep tighter control of removal dependencies by limiting the number

of dirrem structure rather than the collaterally created freeblks
and freefile structures. Limit the rate of buffer dirtying by the
syncer process during periods of intense file removal.

1 files changed, 22 insertions, 20 deletions

diff --git a/sys/ufs/ffs/ffs_softdep.c b/sys/ufs/ffs/ffs_softdep.c
index fde758b..14e1bb2 100644
--- a/sys/ufs/ffs/ffs_softdep.c
+++ b/sys/ufs/ffs/ffs_softdep.c
@@ -52,7 +52,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	from: @(#)ffs_softdep.c	9.44 (McKusick) 1/9/00
+ *	from: @(#)ffs_softdep.c	9.45 (McKusick) 1/9/00
  * $FreeBSD$
  */
 
@@ -537,7 +537,7 @@ softdep_process_worklist(matchmnt)
 	struct proc *p = CURPROC;
 	struct worklist *wk;
 	struct fs *matchfs;
-	int matchcnt;
+	int matchcnt, loopcount;
 
 	/*
 	 * Record the process identifier of our caller so that we can give
@@ -570,6 +570,7 @@ softdep_process_worklist(matchmnt)
 		wakeup(&proc_waiting);
 	}
 	ACQUIRE_LOCK(&lk);
+	loopcount = 1;
 	while ((wk = LIST_FIRST(&softdep_workitem_pending)) != 0) {
 		WORKLIST_REMOVE(wk);
 		FREE_LOCK(&lk);
@@ -623,6 +624,12 @@ softdep_process_worklist(matchmnt)
 			req_clear_remove = 0;
 			wakeup(&proc_waiting);
 		}
+		/*
+		 * We do not generally want to stop for buffer space, but if
+		 * we are really being a buffer hog, we will stop and wait.
+		 */
+		if (loopcount++ % 128 == 0)
+			bwillwrite();
 		ACQUIRE_LOCK(&lk);
 	}
 	FREE_LOCK(&lk);
@@ -1570,7 +1577,6 @@ setup_allocindir_phase2(bp, ip, aip)
  * later release and zero the inode so that the calling routine
  * can release it.
  */
-static long num_freeblks;	/* number of freeblks allocated */
 void
 softdep_setup_freeblocks(ip, length)
 	struct inode *ip;	/* The inode whose length is to be reduced */
@@ -1587,12 +1593,6 @@ softdep_setup_freeblocks(ip, length)
 	fs = ip->i_fs;
 	if (length != 0)
 		panic("softde_setup_freeblocks: non-zero length");
-	/*
-	 * If we are over our limit, try to improve the situation.
-	 */
-	if (num_freeblks > max_softdeps / 2 && speedup_syncer() == 0)
-		(void) request_cleanup(FLUSH_REMOVE, 0);
-	num_freeblks += 1;
 	MALLOC(freeblks, struct freeblks *, sizeof(struct freeblks),
 		M_FREEBLKS, M_WAITOK);
 	bzero(freeblks, sizeof(struct freeblks));
@@ -1813,7 +1813,6 @@ free_allocdirect(adphead, adp, delay)
  * Prepare an inode to be freed. The actual free operation is not
  * done until the zero'ed inode has been written to disk.
  */
-static long num_freefile;	/* number of freefile allocated */
 void
 softdep_freefile(pvp, ino, mode)
 		struct vnode *pvp;
@@ -1825,14 +1824,8 @@ softdep_freefile(pvp, ino, mode)
 	struct freefile *freefile;
 
 	/*
-	 * If we are over our limit, try to improve the situation.
-	 */
-	if (num_freefile > max_softdeps / 2 && speedup_syncer() == 0)
-		(void) request_cleanup(FLUSH_REMOVE, 0);
-	/*
 	 * This sets up the inode de-allocation dependency.
 	 */
-	num_freefile += 1;
 	MALLOC(freefile, struct freefile *, sizeof(struct freefile),
 		M_FREEFILE, M_WAITOK);
 	freefile->fx_list.wk_type = D_FREEFILE;
@@ -1968,7 +1961,6 @@ handle_workitem_freeblocks(freeblks)
 		softdep_error("handle_workitem_freeblks", allerror);
 #endif /* DIAGNOSTIC */
 	WORKITEM_FREE(freeblks, D_FREEBLKS);
-	num_freeblks -= 1;
 }
 
 /*
@@ -2337,6 +2329,7 @@ softdep_setup_remove(bp, dp, ip, isrmdir)
  * Allocate a new dirrem if appropriate and return it along with
  * its associated pagedep. Called without a lock, returns with lock.
  */
+static long num_dirrem;		/* number of dirrem allocated */
 static struct dirrem *
 newdirrem(bp, dp, ip, isrmdir)
 	struct buf *bp;		/* buffer containing directory block */
@@ -2355,6 +2348,14 @@ newdirrem(bp, dp, ip, isrmdir)
 	 */
 	if (ip == NULL)
 		panic("newdirrem: whiteout");
+	/*
+	 * If we are over our limit, try to improve the situation.
+	 * Limiting the number of dirrem structures will also limit
+	 * the number of freefile and freeblks structures.
+	 */
+	if (num_dirrem > max_softdeps / 2 && speedup_syncer() == 0)
+		(void) request_cleanup(FLUSH_REMOVE, 0);
+	num_dirrem += 1;
 	MALLOC(dirrem, struct dirrem *, sizeof(struct dirrem),
 		M_DIRREM, M_WAITOK);
 	bzero(dirrem, sizeof(struct dirrem));
@@ -2558,6 +2559,7 @@ handle_workitem_remove(dirrem)
 			panic("handle_workitem_remove: bad file delta");
 		ip->i_flag |= IN_CHANGE;
 		vput(vp);
+		num_dirrem -= 1;
 		WORKITEM_FREE(dirrem, D_DIRREM);
 		return;
 	}
@@ -2581,6 +2583,7 @@ handle_workitem_remove(dirrem)
 	 */
 	if (dirrem->dm_state & DIRCHG) {
 		vput(vp);
+		num_dirrem -= 1;
 		WORKITEM_FREE(dirrem, D_DIRREM);
 		return;
 	}
@@ -2630,7 +2633,6 @@ handle_workitem_freefile(freefile)
 	if ((error = ffs_freefile(&vp, freefile->fx_oldinum, freefile->fx_mode)) != 0)
 		softdep_error("handle_workitem_freefile", error);
 	WORKITEM_FREE(freefile, D_FREEFILE);
-	num_freefile -= 1;
 }
 
 /*
@@ -4290,8 +4292,8 @@ pause_timer(arg)
 }
 
 /*
- * Flush out a directory with at least one removal dependency in an effort
- * to reduce the number of freefile and freeblks dependency structures.
+ * Flush out a directory with at least one removal dependency in an effort to
+ * reduce the number of dirrem, freefile, and freeblks dependency structures.
  */
 static void
 clear_remove(p)