[PATCH 1/4] xfs: only lock the rt bitmap inode once per allocation
From: kdasu <hidden>
Date: 2012-02-17 22:51:17
Subsystem:
filesystems (vfs and infrastructure), the rest, xfs filesystem · Maintainers:
Alexander Viro, Christian Brauner, Linus Torvalds, Carlos Maiolino
Currently both xfs_rtpick_extent and xfs_rtallocate_extent call
xfs_trans_iget to grab and lock the rt bitmap inode, which results in a
deadlock since the removal of the lock recursion counters in commit
"xfs: simplify inode to transaction joining"
Fix this by acquiring and locking the inode in xfs_bmap_rtalloc before
calling into xfs_rtpick_extent and xfs_rtallocate_extent.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <redacted>
Signed-off-by: Kamal Dasu <redacted>
---
fs/xfs/xfs_bmap.c | 11 +++++++++++
fs/xfs/xfs_rtalloc.c | 34 +++++++++++++---------------------
2 files changed, 24 insertions(+), 21 deletions(-)
diff --git a/fs/xfs/xfs_bmap.c b/fs/xfs/xfs_bmap.c
index 4111cd3..9d9970b 100644
--- a/fs/xfs/xfs_bmap.c
+++ b/fs/xfs/xfs_bmap.c@@ -2316,6 +2316,7 @@ xfs_bmap_rtalloc( xfs_extlen_t prod = 0; /* product factor for allocators */ xfs_extlen_t ralen = 0; /* realtime allocation length */ xfs_extlen_t align; /* minimum allocation alignment */ + xfs_inode_t *ip; /* bitmap incore inode */ xfs_rtblock_t rtb;
kdasu@kdasu-VirtualBox:~/linux-2.6$ more 0001-xfs-only-lock-the-rt-bitmap-inode-once-per-allocatio.patch
From f59ab29cc191a5955c4d44c0b92a537f981184c2 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@infradead.org>
Date: Tue, 25 Jan 2011 09:06:19 +0000
Subject: [PATCH 1/4] xfs: only lock the rt bitmap inode once per allocation
Currently both xfs_rtpick_extent and xfs_rtallocate_extent call
xfs_trans_iget to grab and lock the rt bitmap inode, which results in a
deadlock since the removal of the lock recursion counters in commit
"xfs: simplify inode to transaction joining"
Fix this by acquiring and locking the inode in xfs_bmap_rtalloc before
calling into xfs_rtpick_extent and xfs_rtallocate_extent.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <redacted>
Signed-off-by: Kamal Dasu <redacted>
---
fs/xfs/xfs_bmap.c | 11 +++++++++++
fs/xfs/xfs_rtalloc.c | 34 +++++++++++++---------------------
2 files changed, 24 insertions(+), 21 deletions(-)
diff --git a/fs/xfs/xfs_bmap.c b/fs/xfs/xfs_bmap.c
index 4111cd3..9d9970b 100644
--- a/fs/xfs/xfs_bmap.c
+++ b/fs/xfs/xfs_bmap.c@@ -2316,6 +2316,7 @@ xfs_bmap_rtalloc( xfs_extlen_t prod = 0; /* product factor for allocators */ xfs_extlen_t ralen = 0; /* realtime allocation length */ xfs_extlen_t align; /* minimum allocation alignment */ + xfs_inode_t *ip; /* bitmap incore inode */ xfs_rtblock_t rtb; mp = ap->ip->i_mount;
@@ -2348,6 +2349,16 @@ xfs_bmap_rtalloc( */ if (ralen * mp->m_sb.sb_rextsize >= MAXEXTLEN) ralen = MAXEXTLEN / mp->m_sb.sb_rextsize; + + /* + * Lock out other modifications to the RT bitmap inode. + */ + error = xfs_trans_iget(mp, ap->tp, mp->m_sb.sb_rbmino, 0, + XFS_ILOCK_EXCL, &ip); + if (error) + return error; + ASSERT(ip == mp->m_rbmip); + /* * If it's an allocation to an empty file at offset 0, * pick an extent that will space things out in the rt area.
diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c
index 12a1913..037fab1 100644
--- a/fs/xfs/xfs_rtalloc.c
+++ b/fs/xfs/xfs_rtalloc.c@@ -2075,15 +2075,15 @@ xfs_rtallocate_extent( xfs_extlen_t prod, /* extent product factor */ xfs_rtblock_t *rtblock) /* out: start block allocated */ { + xfs_mount_t *mp = tp->t_mountp; int error; /* error value */ - xfs_inode_t *ip; /* inode for bitmap file */ - xfs_mount_t *mp; /* file system mount structure */ xfs_rtblock_t r; /* result allocated block */ xfs_fsblock_t sb; /* summary file block number */ xfs_buf_t *sumbp; /* summary file block buffer */ + ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL)); ASSERT(minlen > 0 && minlen <= maxlen); - mp = tp->t_mountp; + /* * If prod is set then figure out what to do to minlen and maxlen. */
@@ -2099,12 +2099,7 @@ xfs_rtallocate_extent( return 0; } } - /* - * Lock out other callers by grabbing the bitmap inode lock. - */ - if ((error = xfs_trans_iget(mp, tp, mp->m_sb.sb_rbmino, 0, - XFS_ILOCK_EXCL, &ip))) - return error; + sumbp = NULL; /* * Allocate by size, or near another block, or exactly at some
block.
@@ -2123,11 +2118,12 @@ xfs_rtallocate_extent( len, &sumbp, &sb, prod, &r); break; default: + error = EIO; ASSERT(0); } - if (error) { + if (error) return error; - } + /* * If it worked, update the superblock. */
@@ -2306,20 +2302,16 @@ xfs_rtpick_extent( xfs_rtblock_t *pick) /* result rt extent */ { xfs_rtblock_t b; /* result block */ - int error; /* error return value */ - xfs_inode_t *ip; /* bitmap incore inode */ int log2; /* log of sequence number */ __uint64_t resid; /* residual after log removed */ __uint64_t seq; /* sequence number of file creation
*/
__uint64_t *seqp; /* pointer to seqno in inode */
- if ((error = xfs_trans_iget(mp, tp, mp->m_sb.sb_rbmino, 0,
- XFS_ILOCK_EXCL, &ip)))
- return error;
+
sumbp = NULL;
/*
* Allocate by size, or near another block, or exactly at some
block.@@ -2123,11 +2118,12 @@ xfs_rtallocate_extent( len, &sumbp, &sb, prod, &r); break; default: + error = EIO; ASSERT(0); } - if (error) { + if (error) return error; - } + /* * If it worked, update the superblock. */
@@ -2306,20 +2302,16 @@ xfs_rtpick_extent( xfs_rtblock_t *pick) /* result rt extent */ { xfs_rtblock_t b; /* result block */ - int error; /* error return value */ - xfs_inode_t *ip; /* bitmap incore inode */ int log2; /* log of sequence number */ __uint64_t resid; /* residual after log removed */ __uint64_t seq; /* sequence number of file creation
*/
__uint64_t *seqp; /* pointer to seqno in inode */
- if ((error = xfs_trans_iget(mp, tp, mp->m_sb.sb_rbmino, 0,
- XFS_ILOCK_EXCL, &ip)))
- return error;
- ASSERT(ip == mp->m_rbmip);
- seqp = (__uint64_t *)&ip->i_d.di_atime;
- if (!(ip->i_d.di_flags & XFS_DIFLAG_NEWRTBM)) {
- ip->i_d.di_flags |= XFS_DIFLAG_NEWRTBM;
+ ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
+
+ seqp = (__uint64_t *)&mp->m_rbmip->i_d.di_atime;
+ if (!(mp->m_rbmip->i_d.di_flags & XFS_DIFLAG_NEWRTBM)) {
+ mp->m_rbmip->i_d.di_flags |= XFS_DIFLAG_NEWRTBM;
*seqp = 0;
}
seq = *seqp;@@ -2335,7 +2327,7 @@ xfs_rtpick_extent( b = mp->m_sb.sb_rextents - len; } *seqp = seq + 1; - xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); + xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE); *pick = b; return 0; }
--
1.7.5.4
--
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