Peng Tao 7542274519 pnfsblock: fix writeback deadlock ... We should check if the sector is already initialized before trying to grab the page from page cache. Otherwise when two pages of the same block are written back by two threads each calling from writepage_locked, it can cause deadlock like bellow. [ 1080.972099] INFO: task kswapd0:25 blocked for more than 120 seconds. [ 1080.972377] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1080.972812] kswapd0 D ffff88000c4926c0 0 25 2 0x00000000 [ 1080.972816] ffff88000df276b0 0000000000000046 ffff88000df27640 ffffffff81013ba7 [ 1080.972821] ffff88000c492310 ffff88000df27fd8 ffff88000df27fd8 00000000001d3440 [ 1080.972824] ffff88000c378000 ffff88000c492310 ffff8800175d3d40 ffff880017fc75a8 [ 1080.972828] Call Trace: [ 1080.972860] [<ffffffff81013ba7>] ? read_tsc+0x9/0x19 [ 1080.972877] [<ffffffff810e0b23>] ? lock_page+0x2b/0x2b [ 1080.972899] [<ffffffff81475a1d>] io_schedule+0x63/0x7e [ 1080.972902] [<ffffffff810e0b31>] sleep_on_page+0xe/0x12 [ 1080.972905] [<ffffffff81475fe8>] __wait_on_bit_lock+0x46/0x8f [ 1080.972916] [<ffffffff810822d7>] ? lock_release_holdtime.part.7+0x6b/0x72 [ 1080.972919] [<ffffffff810e0af6>] __lock_page+0x66/0x68 [ 1080.972928] [<ffffffff81072705>] ? autoremove_wake_function+0x3d/0x3d [ 1080.972932] [<ffffffff810e0b1f>] lock_page+0x27/0x2b [ 1080.972934] [<ffffffff810e0bcf>] find_lock_page+0x34/0x57 [ 1080.972937] [<ffffffff810e1738>] find_or_create_page+0x34/0x8a [ 1080.972947] [<ffffffffa034245b>] bl_write_pagelist+0x205/0x6da [blocklayoutdriver] [ 1080.972951] [<ffffffffa034145d>] ? bl_free_lseg+0x38/0x38 [blocklayoutdriver] [ 1080.972995] [<ffffffffa02e27b9>] ? nfs_write_rpcsetup+0x118/0x123 [nfs] [ 1080.973033] [<ffffffffa030246b>] pnfs_generic_pg_writepages+0x10b/0x1f4 [nfs] [ 1080.973089] [<ffffffffa02deaae>] nfs_pageio_doio+0x1a/0x43 [nfs] [ 1080.973098] [<ffffffffa02df035>] nfs_pageio_complete+0x16/0x2d [nfs] [ 1080.973108] [<ffffffffa02e2d8f>] nfs_writepage_locked+0xa0/0xbf [nfs] [ 1080.973119] [<ffffffffa02e36a1>] nfs_writepage+0x16/0x2b [nfs] [ 1080.973122] [<ffffffff810e8762>] ? clear_page_dirty_for_io+0x87/0x9a [ 1080.973133] [<ffffffff810efc5b>] shrink_page_list+0x39b/0x6c8 [ 1080.973139] [<ffffffff810f03bb>] shrink_inactive_list+0x22c/0x39e [ 1080.973144] [<ffffffff810822d7>] ? lock_release_holdtime.part.7+0x6b/0x72 [ 1080.973148] [<ffffffff810f0c33>] shrink_zone+0x445/0x588 [ 1080.973152] [<ffffffff810f1a11>] balance_pgdat+0x2c2/0x56b [ 1080.973170] [<ffffffff81254208>] ? __bitmap_weight+0x34/0x80 [ 1080.973175] [<ffffffff810f1f78>] kswapd+0x2be/0x2fa [ 1080.973179] [<ffffffff810726c8>] ? __init_waitqueue_head+0x4b/0x4b [ 1080.973183] [<ffffffff810f1cba>] ? balance_pgdat+0x56b/0x56b [ 1080.973187] [<ffffffff81071f69>] kthread+0xa8/0xb0 [ 1080.973200] [<ffffffff814806b4>] kernel_thread_helper+0x4/0x10 [ 1080.973205] [<ffffffff81071ec1>] ? __init_kthread_worker+0x5a/0x5a [ 1080.973210] [<ffffffff814806b0>] ? gs_change+0x13/0x13 [ 1080.973213] no locks held by kswapd0/25. Signed-off-by: Peng Tao <peng_tao@emc.com> Signed-off-by: Jim Rees <rees@umich.edu> Cc: stable@kernel.org [3.0] Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>		2011-10-18 09:08:15 -07:00
..
blocklayout	pnfsblock: fix writeback deadlock	2011-10-18 09:08:15 -07:00
objlayout	pnfs-obj: Fix the comp_index != 0 case	2011-08-04 11:54:48 -04:00
cache_lib.c
cache_lib.h	atomic: use <linux/atomic.h>	2011-07-26 16:49:47 -07:00
callback_proc.c	NFSv4.1: Return NFS4ERR_BADSESSION to callbacks during session resets	2011-08-04 11:55:35 -04:00
callback_xdr.c	NFSv4.1: Fix the callback 'highest_used_slotid' behaviour	2011-08-04 11:55:35 -04:00
callback.c
callback.h	NFSv4.1: Fix the callback 'highest_used_slotid' behaviour	2011-08-04 11:55:35 -04:00
client.c	nfs: fix bug about IPv6 address scope checking	2011-10-18 09:08:10 -07:00
delegation.c	NFSv4: Don't use the delegation->inode in nfs_mark_return_delegation()	2011-07-25 15:37:29 -04:00
delegation.h
dir.c	Additional readdir cookie loop information	2011-07-30 14:37:14 -04:00
direct.c	atomic: use <linux/atomic.h>	2011-07-26 16:49:47 -07:00
dns_resolve.c
dns_resolve.h
file.c
fscache-index.c
fscache.c
fscache.h
getroot.c
idmap.c	SUNRPC/NFS: make rpc pipe upcall generic	2011-10-18 09:08:12 -07:00
inode.c
internal.h
iostat.h
Kconfig	pnfs: Automatically select blocks & objects layouts	2011-08-11 17:51:27 -07:00
Makefile	pnfsblock: add blocklayout Kconfig option, Makefile, and stubs	2011-07-31 12:18:15 -04:00
mount_clnt.c
namespace.c
nfs2xdr.c
nfs3acl.c	switch posix_acl_create() to umode_t *	2011-08-01 02:09:42 -04:00
nfs3proc.c	switch posix_acl_create() to umode_t *	2011-08-01 02:09:42 -04:00
nfs3xdr.c
nfs4_fs.h	NFSv4: renewd needs to be able to handle the NFS4ERR_CB_PATH_DOWN error	2011-08-24 15:07:37 -04:00
nfs4filelayout.c	pnfs: make _set_lo_fail generic	2011-10-18 09:08:13 -07:00
nfs4filelayout.h
nfs4filelayoutdev.c
nfs4namespace.c
nfs4proc.c	NFSv4: renewd needs to be able to handle the NFS4ERR_CB_PATH_DOWN error	2011-08-24 15:07:37 -04:00
nfs4renewd.c	NFSv4: The NFSv4.0 client must send RENEW calls if it holds a delegation	2011-08-24 15:07:37 -04:00
nfs4state.c	NFSv4: renewd needs to be able to handle the NFS4ERR_CB_PATH_DOWN error	2011-08-24 15:07:37 -04:00
nfs4xdr.c	pnfs: cleanup_layoutcommit	2011-07-31 12:18:15 -04:00
nfsroot.c
pagelist.c
pnfs_dev.c
pnfs.c	pnfs: recoalesce when ld read pagelist fails	2011-10-18 09:08:14 -07:00
pnfs.h	pnfs: recoalesce when ld read pagelist fails	2011-10-18 09:08:14 -07:00
proc.c
read.c	pnfs: recoalesce when ld read pagelist fails	2011-10-18 09:08:14 -07:00
super.c	VFS: Fix the remaining automounter semantics regressions	2011-09-26 19:16:46 -07:00
symlink.c
sysctl.c
unlink.c
write.c	pnfs: recoalesce when ld write pagelist fails	2011-10-18 09:08:13 -07:00