Btrfs: improve fsync by filtering extents that we want

This is based on Josef's "Btrfs: turbo charge fsync".

The above Josef's patch performs very good in random sync write test,

Btrfs: improve fsync by filtering extents that we want

This is based on Josef's "Btrfs: turbo charge fsync".

The above Josef's patch performs very good in random sync write test,
because we won't have too much extents to merge.

However, it does not performs good on the test:
dd if=/dev/zero of=foobar bs=4k count=12500 oflag=sync

The reason is when we do sequencial sync write, we need to merge the
current extent just with the previous one, so that we can get accumulated
extents to log:

A(4k) --> AA(8k) --> AAA(12k) --> AAAA(16k) ...

So we'll have to flush more and more checksum into log tree, which is the
bottleneck according to my tests.

But we can avoid this by telling fsync the real extents that are needed
to be logged.

With this, I did the above dd sync write test (size=50m),

w/o (orig) w/ (josef's) w/ (this)
SATA 104KB/s 109KB/s 121KB/s
ramdisk 1.5MB/s 1.5MB/s 10.7MB/s (613%)

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>

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Btrfs: turbo charge fsync

At least for the vm workload. Currently on fsync we will

1) Truncate all items in the log tree for the given inode if they exist

and

2)

Btrfs: turbo charge fsync

At least for the vm workload. Currently on fsync we will

1) Truncate all items in the log tree for the given inode if they exist

and

2) Copy all items for a given inode into the log

The problem with this is that for things like VMs you can have lots of
extents from the fragmented writing behavior, and worst yet you may have
only modified a few extents, not the entire thing. This patch fixes this
problem by tracking which transid modified our extent, and then when we do
the tree logging we find all of the extents we've modified in our current
transaction, sort them and commit them. We also only truncate up to the
xattrs of the inode and copy that stuff in normally, and then just drop any
extents in the range we have that exist in the log already. Here are some
numbers of a 50 meg fio job that does random writes and fsync()s after every
write

Original Patched
SATA drive 82KB/s 140KB/s
Fusion drive 431KB/s 2532KB/s

So around 2-6 times faster depending on your hardware. There are a few
corner cases, for example if you truncate at all we have to do it the old
way since there is no way to be sure what is in the log is ok. This
probably could be done smarter, but if you write-fsync-truncate-write-fsync
you deserve what you get. All this work is in RAM of course so if your
inode gets evicted from cache and you read it in and fsync it we'll do it
the slow way if we are still in the same transaction that we last modified
the inode in.

The biggest cool part of this is that it requires no changes to the recovery
code, so if you fsync with this patch and crash and load an old kernel, it
will run the recovery and be a-ok. I have tested this pretty thoroughly
with an fsync tester and everything comes back fine, as well as xfstests.
Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>

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Btrfs: clean up code for merging extent maps

unpin_extent_cache() and add_extent_mapping() shares the same code
that merges extent maps.

Signed-off-by: Li Zefan <lizf@cn.fujitsu

Btrfs: clean up code for merging extent maps

unpin_extent_cache() and add_extent_mapping() shares the same code
that merges extent maps.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

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Btrfs: clean up code for extent_map lookup

lookup_extent_map() and search_extent_map() can share most of code.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris

Btrfs: clean up code for extent_map lookup

lookup_extent_map() and search_extent_map() can share most of code.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

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Btrfs: clean up search_extent_mapping()

rb_node returned by __tree_search() can be a valid pointer or NULL,
but won't be some errno.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com

Btrfs: clean up search_extent_mapping()

rb_node returned by __tree_search() can be a valid pointer or NULL,
but won't be some errno.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

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btrfs: drop gfp parameter from alloc_extent_map

pass GFP_NOFS directly to kmem_cache_alloc

Signed-off-by: David Sterba <dsterba@suse.cz>

btrfs: drop unused parameter from extent_map_tree_init

the GFP flags are not stored anywhere and all allocations are done via
alloc_extent_map(GFP_NOFS).

Signed-off-by: David St

btrfs: drop unused parameter from extent_map_tree_init

the GFP flags are not stored anywhere and all allocations are done via
alloc_extent_map(GFP_NOFS).

Signed-off-by: David Sterba <dsterba@suse.cz>

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Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>

Btrfs: check return value of alloc_extent_map()

I add the check on the return value of alloc_extent_map() to several places.
In addition, alloc_extent_map() returns only the address or N

Btrfs: check return value of alloc_extent_map()

I add the check on the return value of alloc_extent_map() to several places.
In addition, alloc_extent_map() returns only the address or NULL.
Therefore, check by IS_ERR() is unnecessary. So, I remove IS_ERR() checking.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

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btrfs: Allow to add new compression algorithm

Make the code aware of compression type, instead of always assuming
zlib compression.

Also make the zlib workspace function as comm

btrfs: Allow to add new compression algorithm

Make the code aware of compression type, instead of always assuming
zlib compression.

Also make the zlib workspace function as common code for all
compression types.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>

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Btrfs: Use ERR_CAST helpers

Use ERR_CAST(x) rather than ERR_PTR(PTR_ERR(x)). The former makes more
clear what is the purpose of the operation, which otherwise looks like a
no-op.

Btrfs: Use ERR_CAST helpers

Use ERR_CAST(x) rather than ERR_PTR(PTR_ERR(x)). The former makes more
clear what is the purpose of the operation, which otherwise looks like a
no-op.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
type T;
T x;
identifier f;
@@

T f (...) { <+...
- ERR_PTR(PTR_ERR(x))
+ x
...+> }

@@
expression x;
@@

- ERR_PTR(PTR_ERR(x))
+ ERR_CAST(x)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

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include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
incl

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

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Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable

* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
Btrfs: kfree correct pointer during mount

Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable

* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
Btrfs: kfree correct pointer during mount option parsing
Btrfs: use RB_ROOT to intialize rb_trees instead of setting rb_node to NULL

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Btrfs: use RB_ROOT to intialize rb_trees instead of setting rb_node to NULL

btrfs inialize rb trees in quite a number of places by settin rb_node =
NULL; The problem with this is that 1

Btrfs: use RB_ROOT to intialize rb_trees instead of setting rb_node to NULL

btrfs inialize rb trees in quite a number of places by settin rb_node =
NULL; The problem with this is that 17d9ddc72fb8bba0d4f678 in the
linux-next tree adds a new field to that struct which needs to be NULL for
the new rbtree library code to work properly. This patch uses RB_ROOT as
the intializer so all of the relevant fields will be NULL'd. Without the
patch I get a panic.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

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Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable

* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
Btrfs: check total number of devices when

Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable

* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
Btrfs: check total number of devices when removing missing
Btrfs: check return value of open_bdev_exclusive properly
Btrfs: do not mark the chunk as readonly if in degraded mode
Btrfs: run orphan cleanup on default fs root
Btrfs: fix a memory leak in btrfs_init_acl
Btrfs: Use correct values when updating inode i_size on fallocate
Btrfs: remove tree_search() in extent_map.c
Btrfs: Add mount -o compress-force

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Btrfs: remove tree_search() in extent_map.c

This patch removes tree_search() in extent_map.c because it is not called by
anything.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>

Btrfs: remove tree_search() in extent_map.c

This patch removes tree_search() in extent_map.c because it is not called by
anything.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

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Merge branch 'for-next' into for-linus

Conflicts:

kernel/irq/chip.c

tree-wide: fix assorted typos all over the place

That is "success", "unknown", "through", "performance", "[re|un]mapping"
, "access", "default", "reasonable", "[con]currently", "temperat

tree-wide: fix assorted typos all over the place

That is "success", "unknown", "through", "performance", "[re|un]mapping"
, "access", "default", "reasonable", "[con]currently", "temperature"
, "channel", "[un]used", "application", "example","hierarchy", "therefore"
, "[over|under]flow", "contiguous", "threshold", "enough" and others.

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

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Btrfs: avoid null deref in unpin_extent_cache()

I re-orderred the checks to avoid dereferencing "em" if it was null.

Found by smatch static checker.

Signed-off-by: Dan Carp

Btrfs: avoid null deref in unpin_extent_cache()

I re-orderred the checks to avoid dereferencing "em" if it was null.

Found by smatch static checker.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

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Btrfs: search for an allocation hint while filling file COW

The allocator has some nice knobs for sending hints about where
to try and allocate new blocks, but when we're doing file allo

Btrfs: search for an allocation hint while filling file COW

The allocator has some nice knobs for sending hints about where
to try and allocate new blocks, but when we're doing file allocations
we're not sending any hint at all.

This commit adds a simple extent map search to see if we can
quickly and easily find a hint for the allocator.

Signed-off-by: Chris Mason <chris.mason@oracle.com>

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Btrfs: Fix extent replacment race

Data COW means that whenever we write to a file, we replace any old
extent pointers with new ones. There was a window where a readpage
might find t

Btrfs: Fix extent replacment race

Data COW means that whenever we write to a file, we replace any old
extent pointers with new ones. There was a window where a readpage
might find the old extent pointers on disk and cache them in the
extent_map tree in ram in the middle of a given write replacing them.

Even though both the readpage and the write had their respective bytes
in the file locked, the extent readpage inserts may cover more bytes than
it had locked down.

This commit closes the race by keeping the new extent pinned in the extent
map tree until after the on-disk btree is properly setup with the new
extent pointers.

Signed-off-by: Chris Mason <chris.mason@oracle.com>

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Btrfs: switch extent_map to a rw lock

There are two main users of the extent_map tree. The
first is regular file inodes, where it is evenly spread
between readers and writers.

Btrfs: switch extent_map to a rw lock

There are two main users of the extent_map tree. The
first is regular file inodes, where it is evenly spread
between readers and writers.

The second is the chunk allocation tree, which maps blocks from
logical addresses to phyiscal ones, and it is 99.99% reads.

The mapping tree is a point of lock contention during heavy IO
workloads, so this commit switches things to a rw lock.

Signed-off-by: Chris Mason <chris.mason@oracle.com>

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Btrfs: kill btrfs_cache_create

Just use kmem_cache_create directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

Btrfs: don't export symbols

Currently the extent_map code is only for btrfs so don't export it's
symbols.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chris

Btrfs: don't export symbols

Currently the extent_map code is only for btrfs so don't export it's
symbols.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

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Btrfs: remove dead code

merge is always NULL at this point.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>