Re: writeout stalls in current -git
From: David Chinner
Date: Sun Nov 04 2007 - 20:46:12 EST
On Sun, Nov 04, 2007 at 12:19:19PM +0100, Torsten Kaiser wrote:
> On 11/2/07, David Chinner <dgc@xxxxxxx> wrote:
> > That's stalled waiting on the inode cluster buffer lock. That implies
> > that the inode lcuser is already being written out and the inode has
> > been redirtied during writeout.
> >
> > Does the kernel you are testing have the "flush inodes in ascending
> > inode number order" patches applied? If so, can you remove that
> > patch and see if the problem goes away?
>
> I can now confirm, that I see this also with the current mainline-git-version
> I used 2.6.24-rc1-git-b4f555081fdd27d13e6ff39d455d5aefae9d2c0c
> plus the fix for the sg changes in ieee1394.
Ok, so it's probably a side effect of the writeback changes.
Attached are two patches (two because one was in a separate patchset as
a standalone change) that should prevent async writeback from blocking
on locked inode cluster buffers. Apply the xfs-factor-inotobp patch first.
Can you see if this fixes the problem?
Cheers,
Dave.
--
Dave Chinner
Principal Engineer
SGI Australian Software Group
---
fs/xfs/xfs_inode.c | 283 ++++++++++++++++++++++++-----------------------------
1 file changed, 129 insertions(+), 154 deletions(-)
Index: 2.6.x-xfs-new/fs/xfs/xfs_inode.c
===================================================================
--- 2.6.x-xfs-new.orig/fs/xfs/xfs_inode.c 2007-09-12 15:41:22.000000000 +1000
+++ 2.6.x-xfs-new/fs/xfs/xfs_inode.c 2007-09-13 08:57:06.395641940 +1000
@@ -124,6 +124,126 @@ xfs_inobp_check(
#endif
/*
+ * Simple wrapper for calling xfs_imap() that includes error
+ * and bounds checking
+ */
+STATIC int
+xfs_ino_to_imap(
+ xfs_mount_t *mp,
+ xfs_trans_t *tp,
+ xfs_ino_t ino,
+ xfs_imap_t *imap,
+ uint imap_flags)
+{
+ int error;
+
+ error = xfs_imap(mp, tp, ino, imap, imap_flags);
+ if (error) {
+ cmn_err(CE_WARN, "xfs_ino_to_imap: xfs_imap() returned an "
+ "error %d on %s. Returning error.",
+ error, mp->m_fsname);
+ return error;
+ }
+
+ /*
+ * If the inode number maps to a block outside the bounds
+ * of the file system then return NULL rather than calling
+ * read_buf and panicing when we get an error from the
+ * driver.
+ */
+ if ((imap->im_blkno + imap->im_len) >
+ XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) {
+ xfs_fs_cmn_err(CE_ALERT, mp, "xfs_ino_to_imap: "
+ "(imap->im_blkno (0x%llx) + imap->im_len (0x%llx)) > "
+ " XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks) (0x%llx)",
+ (unsigned long long) imap->im_blkno,
+ (unsigned long long) imap->im_len,
+ XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks));
+ return XFS_ERROR(EINVAL);
+ }
+ return 0;
+}
+
+/*
+ * Find the buffer associated with the given inode map
+ * We do basic validation checks on the buffer once it has been
+ * retrieved from disk.
+ */
+STATIC int
+xfs_imap_to_bp(
+ xfs_mount_t *mp,
+ xfs_trans_t *tp,
+ xfs_imap_t *imap,
+ xfs_buf_t **bpp,
+ uint buf_flags,
+ uint imap_flags)
+{
+ int error;
+ int i;
+ int ni;
+ xfs_buf_t *bp;
+
+ error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, imap->im_blkno,
+ (int)imap->im_len, XFS_BUF_LOCK, &bp);
+ if (error) {
+ cmn_err(CE_WARN, "xfs_imap_to_bp: xfs_trans_read_buf()returned "
+ "an error %d on %s. Returning error.",
+ error, mp->m_fsname);
+ return error;
+ }
+
+ /*
+ * Validate the magic number and version of every inode in the buffer
+ * (if DEBUG kernel) or the first inode in the buffer, otherwise.
+ */
+#ifdef DEBUG
+ ni = BBTOB(imap->im_len) >> mp->m_sb.sb_inodelog;
+#else /* usual case */
+ ni = 1;
+#endif
+
+ for (i = 0; i < ni; i++) {
+ int di_ok;
+ xfs_dinode_t *dip;
+
+ dip = (xfs_dinode_t *)xfs_buf_offset(bp,
+ (i << mp->m_sb.sb_inodelog));
+ di_ok = be16_to_cpu(dip->di_core.di_magic) == XFS_DINODE_MAGIC &&
+ XFS_DINODE_GOOD_VERSION(dip->di_core.di_version);
+ if (unlikely(XFS_TEST_ERROR(!di_ok, mp,
+ XFS_ERRTAG_ITOBP_INOTOBP,
+ XFS_RANDOM_ITOBP_INOTOBP))) {
+ if (imap_flags & XFS_IMAP_BULKSTAT) {
+ xfs_trans_brelse(tp, bp);
+ return XFS_ERROR(EINVAL);
+ }
+ XFS_CORRUPTION_ERROR("xfs_imap_to_bp",
+ XFS_ERRLEVEL_HIGH, mp, dip);
+#ifdef DEBUG
+ cmn_err(CE_PANIC,
+ "Device %s - bad inode magic/vsn "
+ "daddr %lld #%d (magic=%x)",
+ XFS_BUFTARG_NAME(mp->m_ddev_targp),
+ (unsigned long long)imap->im_blkno, i,
+ be16_to_cpu(dip->di_core.di_magic));
+#endif
+ xfs_trans_brelse(tp, bp);
+ return XFS_ERROR(EFSCORRUPTED);
+ }
+ }
+
+ xfs_inobp_check(mp, bp);
+
+ /*
+ * Mark the buffer as an inode buffer now that it looks good
+ */
+ XFS_BUF_SET_VTYPE(bp, B_FS_INO);
+
+ *bpp = bp;
+ return 0;
+}
+
+/*
* This routine is called to map an inode number within a file
* system to the buffer containing the on-disk version of the
* inode. It returns a pointer to the buffer containing the
@@ -145,72 +265,19 @@ xfs_inotobp(
xfs_buf_t **bpp,
int *offset)
{
- int di_ok;
xfs_imap_t imap;
xfs_buf_t *bp;
int error;
- xfs_dinode_t *dip;
- /*
- * Call the space management code to find the location of the
- * inode on disk.
- */
imap.im_blkno = 0;
- error = xfs_imap(mp, tp, ino, &imap, XFS_IMAP_LOOKUP);
- if (error != 0) {
- cmn_err(CE_WARN,
- "xfs_inotobp: xfs_imap() returned an "
- "error %d on %s. Returning error.", error, mp->m_fsname);
+ error = xfs_ino_to_imap(mp, tp, ino, &imap, XFS_IMAP_LOOKUP);
+ if (error)
return error;
- }
-
- /*
- * If the inode number maps to a block outside the bounds of the
- * file system then return NULL rather than calling read_buf
- * and panicing when we get an error from the driver.
- */
- if ((imap.im_blkno + imap.im_len) >
- XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) {
- cmn_err(CE_WARN,
- "xfs_inotobp: inode number (%llu + %d) maps to a block outside the bounds "
- "of the file system %s. Returning EINVAL.",
- (unsigned long long)imap.im_blkno,
- imap.im_len, mp->m_fsname);
- return XFS_ERROR(EINVAL);
- }
-
- /*
- * Read in the buffer. If tp is NULL, xfs_trans_read_buf() will
- * default to just a read_buf() call.
- */
- error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, imap.im_blkno,
- (int)imap.im_len, XFS_BUF_LOCK, &bp);
- if (error) {
- cmn_err(CE_WARN,
- "xfs_inotobp: xfs_trans_read_buf() returned an "
- "error %d on %s. Returning error.", error, mp->m_fsname);
+ error = xfs_imap_to_bp(mp, tp, &imap, &bp, XFS_BUF_LOCK, 0);
+ if (error)
return error;
- }
- dip = (xfs_dinode_t *)xfs_buf_offset(bp, 0);
- di_ok =
- be16_to_cpu(dip->di_core.di_magic) == XFS_DINODE_MAGIC &&
- XFS_DINODE_GOOD_VERSION(dip->di_core.di_version);
- if (unlikely(XFS_TEST_ERROR(!di_ok, mp, XFS_ERRTAG_ITOBP_INOTOBP,
- XFS_RANDOM_ITOBP_INOTOBP))) {
- XFS_CORRUPTION_ERROR("xfs_inotobp", XFS_ERRLEVEL_LOW, mp, dip);
- xfs_trans_brelse(tp, bp);
- cmn_err(CE_WARN,
- "xfs_inotobp: XFS_TEST_ERROR() returned an "
- "error on %s. Returning EFSCORRUPTED.", mp->m_fsname);
- return XFS_ERROR(EFSCORRUPTED);
- }
-
- xfs_inobp_check(mp, bp);
- /*
- * Set *dipp to point to the on-disk inode in the buffer.
- */
*dipp = (xfs_dinode_t *)xfs_buf_offset(bp, imap.im_boffset);
*bpp = bp;
*offset = imap.im_boffset;
@@ -251,41 +318,15 @@ xfs_itobp(
xfs_imap_t imap;
xfs_buf_t *bp;
int error;
- int i;
- int ni;
if (ip->i_blkno == (xfs_daddr_t)0) {
- /*
- * Call the space management code to find the location of the
- * inode on disk.
- */
imap.im_blkno = bno;
- if ((error = xfs_imap(mp, tp, ip->i_ino, &imap,
- XFS_IMAP_LOOKUP | imap_flags)))
+ error = xfs_ino_to_imap(mp, tp, ip->i_ino, &imap,
+ XFS_IMAP_LOOKUP | imap_flags);
+ if (error)
return error;
/*
- * If the inode number maps to a block outside the bounds
- * of the file system then return NULL rather than calling
- * read_buf and panicing when we get an error from the
- * driver.
- */
- if ((imap.im_blkno + imap.im_len) >
- XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) {
-#ifdef DEBUG
- xfs_fs_cmn_err(CE_ALERT, mp, "xfs_itobp: "
- "(imap.im_blkno (0x%llx) "
- "+ imap.im_len (0x%llx)) > "
- " XFS_FSB_TO_BB(mp, "
- "mp->m_sb.sb_dblocks) (0x%llx)",
- (unsigned long long) imap.im_blkno,
- (unsigned long long) imap.im_len,
- XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks));
-#endif /* DEBUG */
- return XFS_ERROR(EINVAL);
- }
-
- /*
* Fill in the fields in the inode that will be used to
* map the inode to its buffer from now on.
*/
@@ -303,76 +344,10 @@ xfs_itobp(
}
ASSERT(bno == 0 || bno == imap.im_blkno);
- /*
- * Read in the buffer. If tp is NULL, xfs_trans_read_buf() will
- * default to just a read_buf() call.
- */
- error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, imap.im_blkno,
- (int)imap.im_len, XFS_BUF_LOCK, &bp);
- if (error) {
-#ifdef DEBUG
- xfs_fs_cmn_err(CE_ALERT, mp, "xfs_itobp: "
- "xfs_trans_read_buf() returned error %d, "
- "imap.im_blkno 0x%llx, imap.im_len 0x%llx",
- error, (unsigned long long) imap.im_blkno,
- (unsigned long long) imap.im_len);
-#endif /* DEBUG */
+ error = xfs_imap_to_bp(mp, tp, &imap, &bp, XFS_BUF_LOCK, imap_flags);
+ if (error)
return error;
- }
-
- /*
- * Validate the magic number and version of every inode in the buffer
- * (if DEBUG kernel) or the first inode in the buffer, otherwise.
- * No validation is done here in userspace (xfs_repair).
- */
-#if !defined(__KERNEL__)
- ni = 0;
-#elif defined(DEBUG)
- ni = BBTOB(imap.im_len) >> mp->m_sb.sb_inodelog;
-#else /* usual case */
- ni = 1;
-#endif
-
- for (i = 0; i < ni; i++) {
- int di_ok;
- xfs_dinode_t *dip;
-
- dip = (xfs_dinode_t *)xfs_buf_offset(bp,
- (i << mp->m_sb.sb_inodelog));
- di_ok = be16_to_cpu(dip->di_core.di_magic) == XFS_DINODE_MAGIC &&
- XFS_DINODE_GOOD_VERSION(dip->di_core.di_version);
- if (unlikely(XFS_TEST_ERROR(!di_ok, mp,
- XFS_ERRTAG_ITOBP_INOTOBP,
- XFS_RANDOM_ITOBP_INOTOBP))) {
- if (imap_flags & XFS_IMAP_BULKSTAT) {
- xfs_trans_brelse(tp, bp);
- return XFS_ERROR(EINVAL);
- }
-#ifdef DEBUG
- cmn_err(CE_ALERT,
- "Device %s - bad inode magic/vsn "
- "daddr %lld #%d (magic=%x)",
- XFS_BUFTARG_NAME(mp->m_ddev_targp),
- (unsigned long long)imap.im_blkno, i,
- be16_to_cpu(dip->di_core.di_magic));
-#endif
- XFS_CORRUPTION_ERROR("xfs_itobp", XFS_ERRLEVEL_HIGH,
- mp, dip);
- xfs_trans_brelse(tp, bp);
- return XFS_ERROR(EFSCORRUPTED);
- }
- }
-
- xfs_inobp_check(mp, bp);
- /*
- * Mark the buffer as an inode buffer now that it looks good
- */
- XFS_BUF_SET_VTYPE(bp, B_FS_INO);
-
- /*
- * Set *dipp to point to the on-disk inode in the buffer.
- */
*dipp = (xfs_dinode_t *)xfs_buf_offset(bp, imap.im_boffset);
*bpp = bp;
return 0;
---
fs/xfs/linux-2.6/xfs_super.c | 3 +-
fs/xfs/linux-2.6/xfs_vnode.h | 5 ---
fs/xfs/xfs_inode.c | 33 ++++++++++++++++---------
fs/xfs/xfs_inode.h | 7 +++--
fs/xfs/xfs_vnodeops.c | 55 +++++++++----------------------------------
5 files changed, 41 insertions(+), 62 deletions(-)
Index: 2.6.x-xfs-new/fs/xfs/xfs_inode.c
===================================================================
--- 2.6.x-xfs-new.orig/fs/xfs/xfs_inode.c 2007-11-05 10:17:36.000000000 +1100
+++ 2.6.x-xfs-new/fs/xfs/xfs_inode.c 2007-11-05 10:33:49.590268027 +1100
@@ -306,14 +306,15 @@ xfs_inotobp(
* 0 for the disk block address.
*/
int
-xfs_itobp(
+xfs_itobp_flags(
xfs_mount_t *mp,
xfs_trans_t *tp,
xfs_inode_t *ip,
xfs_dinode_t **dipp,
xfs_buf_t **bpp,
xfs_daddr_t bno,
- uint imap_flags)
+ uint imap_flags,
+ uint buf_flags)
{
xfs_imap_t imap;
xfs_buf_t *bp;
@@ -344,10 +345,17 @@ xfs_itobp(
}
ASSERT(bno == 0 || bno == imap.im_blkno);
- error = xfs_imap_to_bp(mp, tp, &imap, &bp, XFS_BUF_LOCK, imap_flags);
+ error = xfs_imap_to_bp(mp, tp, &imap, &bp, buf_flags, imap_flags);
if (error)
return error;
+ if (!bp) {
+ ASSERT(buf_flags & XFS_BUF_TRYLOCK);
+ ASSERT(tp == NULL);
+ *bpp = NULL;
+ return EAGAIN;
+ }
+
*dipp = (xfs_dinode_t *)xfs_buf_offset(bp, imap.im_boffset);
*bpp = bp;
return 0;
@@ -3068,15 +3076,6 @@ xfs_iflush(
}
/*
- * Get the buffer containing the on-disk inode.
- */
- error = xfs_itobp(mp, NULL, ip, &dip, &bp, 0, 0);
- if (error) {
- xfs_ifunlock(ip);
- return error;
- }
-
- /*
* Decide how buffer will be flushed out. This is done before
* the call to xfs_iflush_int because this field is zeroed by it.
*/
@@ -3125,6 +3124,16 @@ xfs_iflush(
}
/*
+ * Get the buffer containing the on-disk inode.
+ */
+ error = xfs_itobp_flags(mp, NULL, ip, &dip, &bp, 0, 0,
+ (flags == INT_ASYNC) ? XFS_BUF_TRYLOCK : XFS_BUF_LOCK);
+ if (error ||!bp) {
+ xfs_ifunlock(ip);
+ return error;
+ }
+
+ /*
* First flush out the inode that xfs_iflush was called with.
*/
error = xfs_iflush_int(ip, bp);
Index: 2.6.x-xfs-new/fs/xfs/xfs_inode.h
===================================================================
--- 2.6.x-xfs-new.orig/fs/xfs/xfs_inode.h 2007-11-02 13:44:46.000000000 +1100
+++ 2.6.x-xfs-new/fs/xfs/xfs_inode.h 2007-11-05 10:25:44.885153248 +1100
@@ -488,9 +488,12 @@ int xfs_finish_reclaim_all(struct xfs_m
/*
* xfs_inode.c prototypes.
*/
-int xfs_itobp(struct xfs_mount *, struct xfs_trans *,
+int xfs_itobp_flags(struct xfs_mount *, struct xfs_trans *,
xfs_inode_t *, struct xfs_dinode **, struct xfs_buf **,
- xfs_daddr_t, uint);
+ xfs_daddr_t, uint, uint);
+#define xfs_itobp(mp, tp, ip, dipp, bpp, bno, iflags) \
+ xfs_itobp_flags(mp, tp, ip, dipp, bpp, bno, iflags, XFS_BUF_LOCK)
+
int xfs_iread(struct xfs_mount *, struct xfs_trans *, xfs_ino_t,
xfs_inode_t **, xfs_daddr_t, uint);
int xfs_iread_extents(struct xfs_trans *, xfs_inode_t *, int);
Index: 2.6.x-xfs-new/fs/xfs/linux-2.6/xfs_super.c
===================================================================
--- 2.6.x-xfs-new.orig/fs/xfs/linux-2.6/xfs_super.c 2007-11-02 13:44:50.000000000 +1100
+++ 2.6.x-xfs-new/fs/xfs/linux-2.6/xfs_super.c 2007-11-05 10:39:05.969204451 +1100
@@ -840,7 +840,8 @@ xfs_fs_write_inode(
struct inode *inode,
int sync)
{
- int error = 0, flags = FLUSH_INODE;
+ int error = 0;
+ int flags = 0;
xfs_itrace_entry(XFS_I(inode));
if (sync) {
Index: 2.6.x-xfs-new/fs/xfs/linux-2.6/xfs_vnode.h
===================================================================
--- 2.6.x-xfs-new.orig/fs/xfs/linux-2.6/xfs_vnode.h 2007-10-02 16:01:47.000000000 +1000
+++ 2.6.x-xfs-new/fs/xfs/linux-2.6/xfs_vnode.h 2007-11-05 10:40:49.103817818 +1100
@@ -73,12 +73,9 @@ typedef enum bhv_vrwlock {
#define IO_INVIS 0x00020 /* don't update inode timestamps */
/*
- * Flags for vop_iflush call
+ * Flags for xfs_inode_flush
*/
#define FLUSH_SYNC 1 /* wait for flush to complete */
-#define FLUSH_INODE 2 /* flush the inode itself */
-#define FLUSH_LOG 4 /* force the last log entry for
- * this inode out to disk */
/*
* Flush/Invalidate options for vop_toss/flush/flushinval_pages.
Index: 2.6.x-xfs-new/fs/xfs/xfs_vnodeops.c
===================================================================
--- 2.6.x-xfs-new.orig/fs/xfs/xfs_vnodeops.c 2007-11-05 10:02:05.000000000 +1100
+++ 2.6.x-xfs-new/fs/xfs/xfs_vnodeops.c 2007-11-05 10:37:53.398623943 +1100
@@ -3556,29 +3556,6 @@ xfs_inode_flush(
((iip == NULL) || !(iip->ili_format.ilf_fields & XFS_ILOG_ALL)))
return 0;
- if (flags & FLUSH_LOG) {
- if (iip && iip->ili_last_lsn) {
- xlog_t *log = mp->m_log;
- xfs_lsn_t sync_lsn;
- int s, log_flags = XFS_LOG_FORCE;
-
- s = GRANT_LOCK(log);
- sync_lsn = log->l_last_sync_lsn;
- GRANT_UNLOCK(log, s);
-
- if ((XFS_LSN_CMP(iip->ili_last_lsn, sync_lsn) > 0)) {
- if (flags & FLUSH_SYNC)
- log_flags |= XFS_LOG_SYNC;
- error = xfs_log_force(mp, iip->ili_last_lsn, log_flags);
- if (error)
- return error;
- }
-
- if (ip->i_update_core == 0)
- return 0;
- }
- }
-
/*
* We make this non-blocking if the inode is contended,
* return EAGAIN to indicate to the caller that they
@@ -3586,30 +3563,22 @@ xfs_inode_flush(
* blocking on inodes inside another operation right
* now, they get caught later by xfs_sync.
*/
- if (flags & FLUSH_INODE) {
- int flush_flags;
-
- if (flags & FLUSH_SYNC) {
- xfs_ilock(ip, XFS_ILOCK_SHARED);
- xfs_iflock(ip);
- } else if (xfs_ilock_nowait(ip, XFS_ILOCK_SHARED)) {
- if (xfs_ipincount(ip) || !xfs_iflock_nowait(ip)) {
- xfs_iunlock(ip, XFS_ILOCK_SHARED);
- return EAGAIN;
- }
- } else {
+ if (flags & FLUSH_SYNC) {
+ xfs_ilock(ip, XFS_ILOCK_SHARED);
+ xfs_iflock(ip);
+ } else if (xfs_ilock_nowait(ip, XFS_ILOCK_SHARED)) {
+ if (xfs_ipincount(ip) || !xfs_iflock_nowait(ip)) {
+ xfs_iunlock(ip, XFS_ILOCK_SHARED);
return EAGAIN;
}
-
- if (flags & FLUSH_SYNC)
- flush_flags = XFS_IFLUSH_SYNC;
- else
- flush_flags = XFS_IFLUSH_ASYNC;
-
- error = xfs_iflush(ip, flush_flags);
- xfs_iunlock(ip, XFS_ILOCK_SHARED);
+ } else {
+ return EAGAIN;
}
+ error = xfs_iflush(ip, (flags & FLUSH_SYNC) ? XFS_IFLUSH_SYNC
+ : XFS_IFLUSH_ASYNC);
+ xfs_iunlock(ip, XFS_ILOCK_SHARED);
+
return error;
}