Theodore Ts'o f783f091e4 jbd2: trace when lock_buffer in do_get_write_access takes a long time ... While investigating interactivity problems it was clear that processes sometimes stall for long periods of times if an attempt is made to lock a buffer which is undergoing writeback. It would stall in a trace looking something like [<ffffffff811a39de>] __lock_buffer+0x2e/0x30 [<ffffffff8123a60f>] do_get_write_access+0x43f/0x4b0 [<ffffffff8123a7cb>] jbd2_journal_get_write_access+0x2b/0x50 [<ffffffff81220f79>] __ext4_journal_get_write_access+0x39/0x80 [<ffffffff811f3198>] ext4_reserve_inode_write+0x78/0xa0 [<ffffffff811f3209>] ext4_mark_inode_dirty+0x49/0x220 [<ffffffff811f57d1>] ext4_dirty_inode+0x41/0x60 [<ffffffff8119ac3e>] __mark_inode_dirty+0x4e/0x2d0 [<ffffffff8118b9b9>] update_time+0x79/0xc0 [<ffffffff8118ba98>] file_update_time+0x98/0x100 [<ffffffff81110ffc>] __generic_file_aio_write+0x17c/0x3b0 [<ffffffff811112aa>] generic_file_aio_write+0x7a/0xf0 [<ffffffff811ea853>] ext4_file_write+0x83/0xd0 [<ffffffff81172b23>] do_sync_write+0xa3/0xe0 [<ffffffff811731ae>] vfs_write+0xae/0x180 [<ffffffff8117361d>] sys_write+0x4d/0x90 [<ffffffff8159d62d>] system_call_fastpath+0x1a/0x1f [<ffffffffffffffff>] 0xffffffffffffffff Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>		2013-04-21 16:47:54 -04:00
..
9p.h	net/9p: Convert net/9p protocol dumps to tracepoints	2011-10-24 11:13:12 -05:00
asoc.h	ASoC: dapm: Fix x86_64 build warning.	2012-04-23 13:15:35 +01:00
block.h	block: add block_{touch|dirty}_buffer tracepoint	2013-01-14 15:00:36 +01:00
btrfs.h	Btrfs: parse parent 0 into correct value in tracepoint	2012-12-16 20:46:18 -05:00
compaction.h	UAPI: (Scripted) Convert #include "..." to #include <path/...> in kernel system headers	2012-10-02 18:01:25 +01:00
ext3.h	userns: Convert ext3 to use kuid/kgid where appropriate	2012-05-15 14:59:27 -07:00
ext4.h	ext4: fix miscellaneous big endian warnings	2013-04-09 23:59:55 -04:00
gfpflags.h	mm: add a __GFP_KMEMCG flag	2012-12-18 15:02:12 -08:00
gpio.h	gpio: add trace events for setting direction and value	2011-05-20 00:40:19 -06:00
irq.h	rcu: Use softirq to address performance regression	2011-06-14 15:25:39 -07:00
jbd.h	jbd: Write journal superblock with WRITE_FUA after checkpointing	2012-05-15 23:34:37 +02:00
jbd2.h	jbd2: trace when lock_buffer in do_get_write_access takes a long time	2013-04-21 16:47:54 -04:00
kmem.h	UAPI: (Scripted) Convert #include "..." to #include <path/...> in kernel system headers	2012-10-02 18:01:25 +01:00
kvm.h	KVM: trace: Fix exit decoding.	2013-01-10 15:51:11 -02:00
lock.h
mce.h	tracing: Fix event alignment: mce:mce_record	2011-03-10 10:34:28 -05:00
migrate.h	mm: migrate: Add a tracepoint for migrate_pages	2012-12-11 14:28:35 +00:00
module.h	include: replace linux/module.h with "struct module" wherever possible	2011-10-31 19:32:32 -04:00
napi.h
net.h	net: tracepoint of net_dev_xmit sees freed skb and causes panic	2011-06-02 14:06:31 -07:00
oom.h	mm, oom: change type of oom_score_adj to short	2012-12-11 17:22:27 -08:00
power.h	PM / tracing: remove deprecated power trace API	2013-01-26 00:39:12 +01:00
printk.h	printk/tracing: Add console output tracing	2012-02-13 13:46:05 -05:00
random.h	random: add tracepoints for easier debugging and verification	2012-07-14 20:17:48 -04:00
ras.h	aerdrv: Trace Event for PCI Express Advanced Error Reporting	2013-01-03 14:31:44 -08:00
rcu.h	Merge branches 'doctorture.2013.01.29a', 'fixes.2013.01.26a', 'tagcb.2013.01.24a' and 'tiny.2013.01.29b' into HEAD	2013-01-28 22:25:21 -08:00
regmap.h	The following text was taken from the original review request:	2012-03-24 10:41:37 -07:00
regulator.h	regulator: Add basic trace facilities	2011-01-12 14:33:00 +00:00
rpm.h	device.h: audit and cleanup users in main include dir	2012-03-16 10:38:24 -04:00
sched.h	perf/trace: Add ability to set a target task for events	2012-07-31 17:02:05 +02:00
scsi.h	[SCSI] Include protection operation in SCSI command trace	2011-03-14 18:36:02 -05:00
signal.h	tracing: let trace_signal_generate() report more info, kill overflow_fail/lose_info	2012-01-13 18:48:50 +01:00
skb.h	tracing: Fix event alignment: skb:kfree_skb	2011-03-10 10:34:31 -05:00
sock.h	core: add tracepoints for queueing skb to rcvbuf	2011-06-21 16:06:10 -07:00
sunrpc.h	SUNRPC: Adding status trace points	2012-02-06 10:37:53 -05:00
syscalls.h	tracing: Allow raw syscall trace events for non privileged users	2010-11-18 14:37:43 +01:00
task.h	mm, oom: change type of oom_score_adj to short	2012-12-11 17:22:27 -08:00
timer.h
udp.h	udp: add tracepoints for queueing skb to rcvbuf	2011-06-21 16:06:10 -07:00
vmscan.h	UAPI: (Scripted) Convert #include "..." to #include <path/...> in kernel system headers	2012-10-02 18:01:25 +01:00
workqueue.h	workqueue: rename cpu_workqueue to pool_workqueue	2013-02-13 19:29:12 -08:00
writeback.h	writeback: add more tracepoints	2013-01-14 15:00:36 +01:00
xen.h	xen/mmu: Use Xen specific TLB flush instead of the generic one.	2012-10-31 12:38:31 -04:00