linux-toradex.git/fs/ext4/ext4_jbd2.h, branch v3.17-rc2

ext4: make local functions static

2014-05-12T14:50:23+00:00

I have been running make namespacecheck to look for unneeded globals, and
found these in ext4.

Signed-off-by: Stephen Hemminger 
Signed-off-by: "Theodore Ts'o"

ext4: Fix misspellings using 'codespell' tool

2013-08-28T18:40:12+00:00

Signed-off-by: Anatol Pomozov 
Signed-off-by: "Theodore Ts'o"

ext4: use transaction reservation for extent conversion in ext4_end_io

2013-06-04T17:21:11+00:00

Later we would like to clear PageWriteback bit only after extent
conversion from unwritten to written extents is performed.  However it
is not possible to start a transaction after PageWriteback is set
because that violates lock ordering (and is easy to deadlock).  So we
have to reserve a transaction before locking pages and sending them
for IO and later we use the transaction for extent conversion from
ext4_end_io().

Reviewed-by: Zheng Liu 
Signed-off-by: Jan Kara 
Signed-off-by: "Theodore Ts'o"

ext4: provide wrappers for transaction reservation calls

2013-06-04T16:37:50+00:00

Reviewed-by: Zheng Liu 
Signed-off-by: Jan Kara 
Signed-off-by: "Theodore Ts'o"

ext4: improve credit estimate for EXT4_SINGLEDATA_TRANS_BLOCKS

2013-04-09T16:39:26+00:00

Estimate of 27 credits for allocation of a block in extent based inode
is unnecessarily high. We can easily argue 20 is enough.

Signed-off-by: Jan Kara 
Signed-off-by: "Theodore Ts'o"

ext4: fix journal callback list traversal

2013-04-04T02:08:52+00:00

It is incorrect to use list_for_each_entry_safe() for journal callback
traversial because ->next may be removed by other task:
->ext4_mb_free_metadata()
  ->ext4_mb_free_metadata()
    ->ext4_journal_callback_del()

This results in the following issue:

WARNING: at lib/list_debug.c:62 __list_del_entry+0x1c0/0x250()
Hardware name:
list_del corruption. prev->next should be ffff88019a4ec198, but was 6b6b6b6b6b6b6b6b
Modules linked in: cpufreq_ondemand acpi_cpufreq freq_table mperf coretemp kvm_intel kvm crc32c_intel ghash_clmulni_intel microcode sg xhci_hcd button sd_mod crc_t10dif aesni_intel ablk_helper cryptd lrw aes_x86_64 xts gf128mul ahci libahci pata_acpi ata_generic dm_mirror dm_region_hash dm_log dm_mod
Pid: 16400, comm: jbd2/dm-1-8 Tainted: G        W    3.8.0-rc3+ #107
Call Trace:
 [] warn_slowpath_common+0xad/0xf0
 [] warn_slowpath_fmt+0x46/0x50
 [] ? ext4_journal_commit_callback+0x99/0xc0
 [] __list_del_entry+0x1c0/0x250
 [] ext4_journal_commit_callback+0x6f/0xc0
 [] jbd2_journal_commit_transaction+0x23a6/0x2570
 [] ? try_to_del_timer_sync+0x82/0xa0
 [] ? del_timer_sync+0x91/0x1e0
 [] kjournald2+0x19f/0x6a0
 [] ? wake_up_bit+0x40/0x40
 [] ? bit_spin_lock+0x80/0x80
 [] kthread+0x10e/0x120
 [] ? __init_kthread_worker+0x70/0x70
 [] ret_from_fork+0x7c/0xb0
 [] ? __init_kthread_worker+0x70/0x70

This patch fix the issue as follows:
- ext4_journal_commit_callback() make list truly traversial safe
  simply by always starting from list_head
- fix race between two ext4_journal_callback_del() and
  ext4_journal_callback_try_del()

Signed-off-by: Dmitry Monakhov 
Signed-off-by: "Theodore Ts'o" 
Reviewed-by: Jan Kara 
Cc: stable@vger.kernel.com

ext4: fix the number of credits needed for acl ops with inline data

2013-02-09T20:23:03+00:00

Operations which modify extended attributes may need extra journal
credits if inline data is used, since there is a chance that some
extended attributes may need to get pushed to an external attribute
block.

Changes to reflect this was made in xattr.c, but they were missed in
fs/ext4/acl.c.  To fix this, abstract the calculation of the number of
credits needed for xattr operations to an inline function defined in
ext4_jbd2.h, and use it in acl.c and xattr.c.

Also move the function declarations used in inline.c from xattr.h
(where they are non-obviously hidden, and caused problems since
ext4_jbd2.h needs to use the function ext4_has_inline_data), and move
them to ext4.h.

Signed-off-by: "Theodore Ts'o" 
Reviewed-by: Tao Ma 
Reviewed-by: Jan Kara

ext4: fix the number of credits needed for ext4_unlink() and ext4_rmdir()

2013-02-09T20:06:24+00:00

The ext4_unlink() and ext4_rmdir() don't actually release the blocks
associated with the file/directory.  This gets done in a separate jbd2
handle called via ext4_evict_inode().  Thus, we don't need to reserve
lots of journal credits for the truncate.

Note that using too many journal credits is non-optimal because it can
leading to the journal transmit getting closed too early, before it is
strictly necessary.

Signed-off-by: "Theodore Ts'o" 
Reviewed-by: Jan Kara

ext4: pass context information to jbd2__journal_start()

2013-02-09T02:59:22+00:00

So we can better understand what bits of ext4 are responsible for
long-running jbd2 handles, use jbd2__journal_start() so we can pass
context information for logging purposes.

The recommended way for finding the longer-running handles is:

   T=/sys/kernel/debug/tracing
   EVENT=$T/events/jbd2/jbd2_handle_stats
   echo "interval > 5" > $EVENT/filter
   echo 1 > $EVENT/enable

   ./run-my-fs-benchmark

   cat $T/trace > /tmp/problem-handles

This will list handles that were active for longer than 20ms.  Having
longer-running handles is bad, because a commit started at the wrong
time could stall for those 20+ milliseconds, which could delay an
fsync() or an O_SYNC operation.  Here is an example line from the
trace file describing a handle which lived on for 311 jiffies, or over
1.2 seconds:

postmark-2917  [000] ....   196.435786: jbd2_handle_stats: dev 254,32 
   tid 570 type 2 line_no 2541 interval 311 sync 0 requested_blocks 1
   dirtied_blocks 0

Signed-off-by: "Theodore Ts'o"

ext4: remove ext4_handle_release_buffer()

2012-11-08T16:22:46+00:00

ext4_handle_release_buffer() was intended to remove journal
write access from a buffer, but it doesn't actually do anything
at all other than add a BUFFER_TRACE point, but it's not reliably
used for that either.  Remove all the associated dead code.

Signed-off-by: Eric Sandeen 
Signed-off-by: "Theodore Ts'o" 
Reviewed-by: Carlos Maiolino