linux-stable.git/include/trace/events/ext4.h, branch v5.8

ext4: mballoc: use lock for checking free blocks while retrying

2020-06-04T03:16:53+00:00

Currently while doing block allocation grp->bb_free may be getting
modified if discard is happening in parallel.
For e.g. consider a case where there are lot of threads who have
preallocated lot of blocks and there is a thread which is trying
to discard all of this group's PA. Now it could happen that
we see all of those group's bb_free is zero and fail the allocation
while there is sufficient space if we free up all the PA.

So this patch adds another flag "EXT4_MB_STRICT_CHECK" which will be set
if we are unable to allocate any blocks in the first try (since we may
not have considered blocks about to be discarded from PA lists).
So during retry attempt to allocate blocks we will use ext4_lock_group()
for checking if the group is good or not.

Signed-off-by: Ritesh Harjani 
Link: https://lore.kernel.org/r/9cb740a117c958c36596f167b12af1beae9a68b7.1589955723.git.riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o

ext4: translate a few more map flags to strings in tracepoints

2020-06-04T03:16:49+00:00

As new ext4_map_blocks() flags have been added, not all have gotten flag
bit to string translations to make tracepoint output more readable.
Fix that, and go one step further by adding a translation for the
EXT4_EX_NOCACHE flag as well.  The EXT4_EX_FORCE_CACHE flag can never
be set in a tracepoint in the current code, so there's no need to
bother with a translation for it right now.

Signed-off-by: Eric Whitney 
Reviewed-by: Jan Kara 
Link: https://lore.kernel.org/r/20200415203140.30349-3-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o

ext4: remove EXT4_GET_BLOCKS_KEEP_SIZE flag

2020-06-04T03:16:48+00:00

The eofblocks code was removed in the 5.7 release by "ext4: remove
EOFBLOCKS_FL and associated code" (4337ecd1fe99).  The ext4_map_blocks()
flag used to trigger it can now be removed as well.

Signed-off-by: Eric Whitney 
Reviewed-by: Jan Kara 
Link: https://lore.kernel.org/r/20200415203140.30349-2-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o

ext4: fix extent_status trace points

2020-01-25T07:03:03+00:00

Show pblock only if it has meaningful value.

# before
   ext4:ext4_es_lookup_extent_exit: dev 253,0 ino 12 found 1 [1/4294967294) 576460752303423487 H
   ext4:ext4_es_lookup_extent_exit: dev 253,0 ino 12 found 1 [2/4294967293) 576460752303423487 HR
# after
   ext4:ext4_es_lookup_extent_exit: dev 253,0 ino 12 found 1 [1/4294967294) 0 H
   ext4:ext4_es_lookup_extent_exit: dev 253,0 ino 12 found 1 [2/4294967293) 0 HR

Signed-off-by: Dmitry Monakhov 
Link: https://lore.kernel.org/r/20191114200147.1073-2-dmonakhov@gmail.com
Signed-off-by: Theodore Ts'o

ext4: fix symbolic enum printing in trace output

2020-01-25T07:03:02+00:00

Trace's macro __print_flags() produce raw event's decraration w/o knowing actual
flags value

cat /sys/kernel/debug/tracing/events/ext4/ext4_ext_map_blocks_exit/format
..
__print_flags(REC->mflags, "", { (1 << BH_New),

For that reason we have to explicitly define it via special macro TRACE_DEFINE_ENUM()
Also add missed EXTENT_STATUS_REFERENCED flag.

#Before patch
ext4:ext4_ext_map_blocks_exit: dev 253,0 ino 2 flags  lblk 0 pblk 4177 len 1 mflags 0x20 ret 1
ext4:ext4_ext_map_blocks_exit: dev 253,0 ino 12 flags CREATE lblk 0 pblk 34304 len 1 mflags 0x60 ret 1

#With patch
ext4:ext4_ext_map_blocks_exit: dev 253,0 ino 2 flags  lblk 0 pblk 4177 len 1 mflags M ret 1
ext4:ext4_ext_map_blocks_exit: dev 253,0 ino 12 flags CREATE lblk 0 pblk 34816 len 1 mflags NM ret 1

Signed-off-by: Dmitry Monakhov 
Link: https://lore.kernel.org/r/20191114200147.1073-1-dmonakhov@gmail.com
Signed-off-by: Theodore Ts'o

ext4: Reserve revoke credits for freed blocks

2019-11-05T21:00:49+00:00

So far we have reserved only relatively high fixed amount of revoke
credits for each transaction. We over-reserved by large amount for most
cases but when freeing large directories or files with data journalling,
the fixed amount is not enough. In fact the worst case estimate is
inconveniently large (maximum extent size) for freeing of one extent.

We fix this by doing proper estimate of the amount of blocks that need
to be revoked when removing blocks from the inode due to truncate or
hole punching and otherwise reserve just a small amount of revoke
credits for each transaction to accommodate freeing of xattrs block or
so.

Signed-off-by: Jan Kara 
Link: https://lore.kernel.org/r/20191105164437.32602-23-jack@suse.cz
Signed-off-by: Theodore Ts'o

ext4: force inode writes when nfsd calls commit_metadata()

2018-12-19T19:07:58+00:00

Some time back, nfsd switched from calling vfs_fsync() to using a new
commit_metadata() hook in export_operations().  If the file system did
not provide a commit_metadata() hook, it fell back to using
sync_inode_metadata().  Unfortunately doesn't work on all file
systems.  In particular, it doesn't work on ext4 due to how the inode
gets journalled --- the VFS writeback code will not always call
ext4_write_inode().

So we need to provide our own ext4_nfs_commit_metdata() method which
calls ext4_write_inode() directly.

Google-Bug-Id: 121195940
Signed-off-by: Theodore Ts'o 
Cc: stable@kernel.org

ext4: adjust reserved cluster count when removing extents

2018-10-01T18:25:08+00:00

Modify ext4_ext_remove_space() and the code it calls to correct the
reserved cluster count for pending reservations (delayed allocated
clusters shared with allocated blocks) when a block range is removed
from the extent tree.  Pending reservations may be found for the clusters
at the ends of written or unwritten extents when a block range is removed.
If a physical cluster at the end of an extent is freed, it's necessary
to increment the reserved cluster count to maintain correct accounting
if the corresponding logical cluster is shared with at least one
delayed and unwritten extent as found in the extents status tree.

Add a new function, ext4_rereserve_cluster(), to reapply a reservation
on a delayed allocated cluster sharing blocks with a freed allocated
cluster.  To avoid ENOSPC on reservation, a flag is applied to
ext4_free_blocks() to briefly defer updating the freeclusters counter
when an allocated cluster is freed.  This prevents another thread
from allocating the freed block before the reservation can be reapplied.

Redefine the partial cluster object as a struct to carry more state
information and to clarify the code using it.

Adjust the conditional code structure in ext4_ext_remove_space to
reduce the indentation level in the main body of the code to improve
readability.

Signed-off-by: Eric Whitney 
Signed-off-by: Theodore Ts'o

ext4: fix reserved cluster accounting at delayed write time

2018-10-01T18:19:37+00:00

The code in ext4_da_map_blocks sometimes reserves space for more
delayed allocated clusters than it should, resulting in premature
ENOSPC, exceeded quota, and inaccurate free space reporting.

Fix this by checking for written and unwritten blocks shared in the
same cluster with the newly delayed allocated block.  A cluster
reservation should not be made for a cluster for which physical space
has already been allocated.

Signed-off-by: Eric Whitney 
Signed-off-by: Theodore Ts'o

ext4: generalize extents status tree search functions

2018-10-01T18:10:39+00:00

Ext4 contains a few functions that are used to search for delayed
extents or blocks in the extents status tree.  Rather than duplicate
code to add new functions to search for extents with different status
values, such as written or a combination of delayed and unwritten,
generalize the existing code to search for caller-specified extents
status values.  Also, move this code into extents_status.c where it
is better associated with the data structures it operates upon, and
where it can be more readily used to implement new extents status tree
functions that might want a broader scope for i_es_lock.

Three missing static specifiers in RFC version of patch reported and
fixed by Fengguang Wu .

Signed-off-by: Eric Whitney 
Signed-off-by: Theodore Ts'o