svn commit: r196973 - stable/6/sys/ufs/ffs

[Attilio Rao]

Author: attilio
Date: Tue Sep  8 14:19:14 2009
New Revision: 196973
URL: http://svn.freebsd.org/changeset/base/196973

Log:
  MFC r180758:
  Prevent the bdflush() activity when trying to lock an indirect block buffer
  setting TDP_INBDFUSH in the appropriate code paths.
  
  Sponsored by:	Sandvine Incorporated

Modified:
  stable/6/sys/ufs/ffs/ffs_balloc.c

Modified: stable/6/sys/ufs/ffs/ffs_balloc.c
==============================================================================
--- stable/6/sys/ufs/ffs/ffs_balloc.c	Tue Sep  8 14:15:14 2009	(r196972)
+++ stable/6/sys/ufs/ffs/ffs_balloc.c	Tue Sep  8 14:19:14 2009	(r196973)
@@ -104,6 +104,7 @@ ffs_balloc_ufs1(struct vnode *vp, off_t 
 	ufs1_daddr_t *allocib, *blkp, *allocblk, allociblk[NIADDR + 1];
 	ufs2_daddr_t *lbns_remfree, lbns[NIADDR + 1];
 	int unwindidx = -1;
+	int saved_inbdflush;
 
 	ip = VTOI(vp);
 	dp = ip->i_din1;
@@ -225,6 +226,9 @@ ffs_balloc_ufs1(struct vnode *vp, off_t 
 	if (num < 1)
 		panic ("ffs_balloc_ufs1: ufs_getlbns returned indirect block");
 #endif
+	saved_inbdflush = ~TDP_INBDFLUSH | (curthread->td_pflags &
+	    TDP_INBDFLUSH);
+	curthread->td_pflags |= TDP_INBDFLUSH;
 	/*
 	 * Fetch the first indirect block allocating if necessary.
 	 */
@@ -237,8 +241,10 @@ ffs_balloc_ufs1(struct vnode *vp, off_t 
 		UFS_LOCK(ump);
 		pref = ffs_blkpref_ufs1(ip, lbn, 0, (ufs1_daddr_t *)0);
 	        if ((error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize,
-		    cred, &newb)) != 0)
+		    cred, &newb)) != 0) {
+			curthread->td_pflags &= saved_inbdflush;
 			return (error);
+		}
 		nb = newb;
 		*allocblk++ = nb;
 		*lbns_remfree++ = indirs[1].in_lbn;
@@ -329,6 +335,7 @@ ffs_balloc_ufs1(struct vnode *vp, off_t 
 	 * If asked only for the indirect block, then return it.
 	 */
 	if (flags & BA_METAONLY) {
+		curthread->td_pflags &= saved_inbdflush;
 		*bpp = bp;
 		return (0);
 	}
@@ -366,6 +373,7 @@ ffs_balloc_ufs1(struct vnode *vp, off_t 
 				bp->b_flags |= B_CLUSTEROK;
 			bdwrite(bp);
 		}
+		curthread->td_pflags &= saved_inbdflush;
 		*bpp = nbp;
 		return (0);
 	}
@@ -387,9 +395,11 @@ ffs_balloc_ufs1(struct vnode *vp, off_t 
 		nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0, 0);
 		nbp->b_blkno = fsbtodb(fs, nb);
 	}
+	curthread->td_pflags &= saved_inbdflush;
 	*bpp = nbp;
 	return (0);
 fail:
+	curthread->td_pflags &= saved_inbdflush;
 	/*
 	 * If we have failed to allocate any blocks, simply return the error.
 	 * This is the usual case and avoids the need to fsync the file.
@@ -489,6 +499,7 @@ ffs_balloc_ufs2(struct vnode *vp, off_t 
 	ufs2_daddr_t *lbns_remfree, lbns[NIADDR + 1];
 	int deallocated, osize, nsize, num, i, error;
 	int unwindidx = -1;
+	int saved_inbdflush;
 
 	ip = VTOI(vp);
 	dp = ip->i_din2;
@@ -719,6 +730,9 @@ ffs_balloc_ufs2(struct vnode *vp, off_t 
 	if (num < 1)
 		panic ("ffs_balloc_ufs2: ufs_getlbns returned indirect block");
 #endif
+	saved_inbdflush = ~TDP_INBDFLUSH | (curthread->td_pflags &
+	    TDP_INBDFLUSH);
+	curthread->td_pflags |= TDP_INBDFLUSH;
 	/*
 	 * Fetch the first indirect block allocating if necessary.
 	 */
@@ -731,8 +745,10 @@ ffs_balloc_ufs2(struct vnode *vp, off_t 
 		UFS_LOCK(ump);
 		pref = ffs_blkpref_ufs2(ip, lbn, 0, (ufs2_daddr_t *)0);
 	        if ((error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize,
-		    cred, &newb)) != 0)
+		    cred, &newb)) != 0) {
+			curthread->td_pflags &= saved_inbdflush;
 			return (error);
+		}
 		nb = newb;
 		*allocblk++ = nb;
 		*lbns_remfree++ = indirs[1].in_lbn;
@@ -823,6 +839,7 @@ ffs_balloc_ufs2(struct vnode *vp, off_t 
 	 * If asked only for the indirect block, then return it.
 	 */
 	if (flags & BA_METAONLY) {
+		curthread->td_pflags &= saved_inbdflush;
 		*bpp = bp;
 		return (0);
 	}
@@ -860,6 +877,7 @@ ffs_balloc_ufs2(struct vnode *vp, off_t 
 				bp->b_flags |= B_CLUSTEROK;
 			bdwrite(bp);
 		}
+		curthread->td_pflags &= saved_inbdflush;
 		*bpp = nbp;
 		return (0);
 	}
@@ -887,9 +905,11 @@ ffs_balloc_ufs2(struct vnode *vp, off_t 
 		nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0, 0);
 		nbp->b_blkno = fsbtodb(fs, nb);
 	}
+	curthread->td_pflags &= saved_inbdflush;
 	*bpp = nbp;
 	return (0);
 fail:
+	curthread->td_pflags &= saved_inbdflush;
 	/*
 	 * If we have failed to allocate any blocks, simply return the error.
 	 * This is the usual case and avoids the need to fsync the file.