- 14 2月, 2009 1 次提交
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由 Aneesh Kumar K.V 提交于
With delayed allocation we lock the page in write_cache_pages() and try to build an in memory extent of contiguous blocks. This is needed so that we can get large contiguous blocks request. If range_cyclic mode is enabled, write_cache_pages() will loop back to the 0 index if no I/O has been done yet, and try to start writing from the beginning of the range. That causes an attempt to take the page lock of lower index page while holding the page lock of higher index page, which can cause a dead lock with another writeback thread. The solution is to implement the range_cyclic behavior in ext4_da_writepages() instead. http://bugzilla.kernel.org/show_bug.cgi?id=12579Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 11 2月, 2009 1 次提交
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由 Jan Kara 提交于
If we race with commit code setting i_transaction to NULL, we could possibly dereference it. Proper locking requires the journal pointer (to access journal->j_list_lock), which we don't have. So we have to change the prototype of the function so that filesystem passes us the journal pointer. Also add a more detailed comment about why the function jbd2_journal_begin_ordered_truncate() does what it does and how it should be used. Thanks to Dan Carpenter <error27@gmail.com> for pointing to the suspitious code. Signed-off-by: NJan Kara <jack@suse.cz> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu> Acked-by: NJoel Becker <joel.becker@oracle.com> CC: linux-ext4@vger.kernel.org CC: ocfs2-devel@oss.oracle.com CC: mfasheh@suse.de CC: Dan Carpenter <error27@gmail.com>
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- 30 1月, 2009 1 次提交
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由 Theodore Ts'o 提交于
The code to support journal-less ext4 operation added a BUG to ext4_bmap() which fired if there was no journal and the EXT4_STATE_JDATA bit was set in the i_state field. This caused running the filefrag program (which uses the FIMBAP ioctl) to trigger a BUG(). The EXT4_STATE_JDATA bit is only used for ext4_bmap(), and it's harmless for the bit to be set. We could add a check in __ext4_journalled_writepage() and ext4_journalled_write_end() to only set the EXT4_STATE_JDATA bit if the journal is present, but that adds an extra test and jump instruction. It's easier to simply remove the BUG check. http://bugzilla.kernel.org/show_bug.cgi?id=12568Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu> Cc: stable@kernel.org
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- 20 1月, 2009 1 次提交
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由 Theodore Ts'o 提交于
When trying to unlink a file with indirect blocks on a filesystem without a journal, the "circular indirect block" sanity test was getting falsely triggered. Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 18 1月, 2009 1 次提交
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由 Theodore Ts'o 提交于
Directories are not allowed to be bigger than 2GB, so don't use i_size_high for anything other than regular files. E2fsck should complain about these inodes, but the simplest thing to do for the kernel is to only use i_size_high for regular files. This prevents an intentially corrupted filesystem from causing the kernel to burn a huge amount of CPU and issuing error messages such as: EXT4-fs warning (device loop0): ext4_block_to_path: block 135090028 > max Thanks to David Maciejak from Fortinet's FortiGuard Global Security Research Team for reporting this issue. http://bugzilla.kernel.org/show_bug.cgi?id=12375Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu> Cc: stable@kernel.org
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- 07 1月, 2009 1 次提交
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由 Eric Dumazet 提交于
For NR_CPUS >= 16 values, FBC_BATCH is 2*NR_CPUS Considering more and more distros are using high NR_CPUS values, it makes sense to use a more sensible value for FBC_BATCH, and get rid of NR_CPUS. A sensible value is 2*num_online_cpus(), with a minimum value of 32 (This minimum value helps branch prediction in __percpu_counter_add()) We already have a hotcpu notifier, so we can adjust FBC_BATCH dynamically. We rename FBC_BATCH to percpu_counter_batch since its not a constant anymore. Signed-off-by: NEric Dumazet <dada1@cosmosbay.com> Acked-by: NDavid S. Miller <davem@davemloft.net> Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 05 1月, 2009 1 次提交
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由 Nick Piggin 提交于
With the write_begin/write_end aops, page_symlink was broken because it could no longer pass a GFP_NOFS type mask into the point where the allocations happened. They are done in write_begin, which would always assume that the filesystem can be entered from reclaim. This bug could cause filesystem deadlocks. The funny thing with having a gfp_t mask there is that it doesn't really allow the caller to arbitrarily tinker with the context in which it can be called. It couldn't ever be GFP_ATOMIC, for example, because it needs to take the page lock. The only thing any callers care about is __GFP_FS anyway, so turn that into a single flag. Add a new flag for write_begin, AOP_FLAG_NOFS. Filesystems can now act on this flag in their write_begin function. Change __grab_cache_page to accept a nofs argument as well, to honour that flag (while we're there, change the name to grab_cache_page_write_begin which is more instructive and does away with random leading underscores). This is really a more flexible way to go in the end anyway -- if a filesystem happens to want any extra allocations aside from the pagecache ones in ints write_begin function, it may now use GFP_KERNEL (rather than GFP_NOFS) for common case allocations (eg. ocfs2_alloc_write_ctxt, for a random example). [kosaki.motohiro@jp.fujitsu.com: fix ubifs] [kosaki.motohiro@jp.fujitsu.com: fix fuse] Signed-off-by: NNick Piggin <npiggin@suse.de> Reviewed-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: <stable@kernel.org> [2.6.28.x] Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> [ Cleaned up the calling convention: just pass in the AOP flags untouched to the grab_cache_page_write_begin() function. That just simplifies everybody, and may even allow future expansion of the logic. - Linus ] Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 04 1月, 2009 1 次提交
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由 Theodore Ts'o 提交于
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 06 1月, 2009 1 次提交
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由 Aneesh Kumar K.V 提交于
Rename the lower bits with suffix _lo and add helper to access the values. Also rename bg_itable_unused_hi to bg_pad as in e2fsprogs. Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 01 1月, 2009 1 次提交
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由 Duane Griffin 提交于
Ensure fast symlink targets are NUL-terminated, even if corrupted on-disk. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Theodore Ts'o <tytso@mit.edu> Cc: adilger@sun.com Cc: linux-ext4@vger.kernel.org Signed-off-by: NDuane Griffin <duaneg@dghda.com> Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
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- 07 11月, 2008 1 次提交
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由 Aneesh Kumar K.V 提交于
We need to make sure we mark the buffer_heads as dirty and uptodate so that block_write_full_page write them correctly. This fixes mmap corruptions that can occur in low memory situations. Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 23 11月, 2008 1 次提交
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由 Aneesh Kumar K.V 提交于
* Change EXT4_HAS_*_FEATURE to return a boolean * Add a function prototype for ext4_fiemap() in ext4.h * Make ext4_ext_fiemap_cb() and ext4_xattr_fiemap() be static functions * Add lock annotations to mb_free_blocks() Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 07 11月, 2008 1 次提交
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由 Theodore Ts'o 提交于
This fixes a 2.6.27 regression which was introduced in commit a02908f1. We weren't passing the chunk parameter down to the two subections, ext4_indirect_trans_blocks() and ext4_ext_index_trans_blocks(), with the result that massively overestimate the amount of credits needed by ext4_da_writepages, especially in the non-extents case. This causes failures especially on /boot partitions, which tend to be small and non-extent using since GRUB doesn't handle extents. This patch fixes the bug reported by Joseph Fannin at: http://bugzilla.kernel.org/show_bug.cgi?id=11964Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 05 11月, 2008 1 次提交
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由 Theodore Ts'o 提交于
Convert the unsigned longs that are most responsible for bloating the stack usage on 64-bit systems. Nearly all places in the ext3/4 code which uses "unsigned long" is probably a bug, since on 32-bit systems a ulong a 32-bits, which means we are wasting stack space on 64-bit systems. Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 07 1月, 2009 1 次提交
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由 Frank Mayhar 提交于
A few weeks ago I posted a patch for discussion that allowed ext4 to run without a journal. Since that time I've integrated the excellent comments from Andreas and fixed several serious bugs. We're currently running with this patch and generating some performance numbers against both ext2 (with backported reservations code) and ext4 with and without a journal. It just so happens that running without a journal is slightly faster for most everything. We did iozone -T -t 4 s 2g -r 256k -T -I -i0 -i1 -i2 which creates 4 threads, each of which create and do reads and writes on a 2G file, with a buffer size of 256K, using O_DIRECT for all file opens to bypass the page cache. Results: ext2 ext4, default ext4, no journal initial writes 13.0 MB/s 15.4 MB/s 15.7 MB/s rewrites 13.1 MB/s 15.6 MB/s 15.9 MB/s reads 15.2 MB/s 16.9 MB/s 17.2 MB/s re-reads 15.3 MB/s 16.9 MB/s 17.2 MB/s random readers 5.6 MB/s 5.6 MB/s 5.7 MB/s random writers 5.1 MB/s 5.3 MB/s 5.4 MB/s So it seems that, so far, this was a useful exercise. Signed-off-by: NFrank Mayhar <fmayhar@google.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 06 1月, 2009 1 次提交
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由 Aneesh Kumar K.V 提交于
When iterating through the pages which have mapped buffer_heads, we failed to update the b_state value. This results in allocating blocks at logical offset 0. Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu> Cc: stable@kernel.org
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- 05 11月, 2008 1 次提交
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由 Theodore Ts'o 提交于
If the filesystem has errors, ext4_da_writepages() will return a *lot* of errors, including lots and lots of stack dumps. While it's true that we are dropping user data on the floor, which is unfortunate, the stack dumps aren't helpful, and they tend to obscure the true original root cause of the problem. So in the case where the filesystem has aborted, return an EROFS right away. Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 02 1月, 2009 1 次提交
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由 Theodore Ts'o 提交于
There was only one caller of the compatibility function ext4_new_blocks(), in balloc.c's ext4_alloc_blocks(). Change it to call ext4_mb_new_blocks() directly, and remove ext4_new_blocks() altogether. This cleans up the code, by removing two extra functions from the call chain, and hopefully saving some stack usage. Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 30 10月, 2008 1 次提交
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由 Alexander Beregalov 提交于
fs/ext4/balloc.c:607: warning: format '%lld' expects type 'long long int', but argument 2 has type 's64' fs/ext4/inode.c:1822: warning: format '%lld' expects type 'long long int', but argument 2 has type 's64' fs/ext4/inode.c:1824: warning: format '%lld' expects type 'long long int', but argument 2 has type 's64' Signed-off-by: NAlexander Beregalov <a.beregalov@gmail.com> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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- 17 10月, 2008 1 次提交
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由 Theodore Ts'o 提交于
If the HUGE_FILE feature flag is not set, don't allow the creation of large files, instead of automatically enabling the feature flag. Recent versions of mke2fs will set the HUGE_FILE flag automatically anyway for ext4 filesystems. Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 16 10月, 2008 1 次提交
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由 Aneesh Kumar K.V 提交于
The range_cyclic writeback mode uses the address_space writeback_index as the start index for writeback. With delayed allocation we were updating writeback_index wrongly resulting in highly fragmented file. This patch reduces the number of extents reduced from 4000 to 27 for a 3GB file. Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
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- 14 10月, 2008 1 次提交
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由 Aneesh Kumar K.V 提交于
This enables us to drop the range_cont writeback mode use from ext4_da_writepages. Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
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- 11 10月, 2008 1 次提交
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由 Theodore Ts'o 提交于
The ext4 filesystem is getting stable enough that it's time to drop the "dev" prefix. Also remove the requirement for the TEST_FILESYS flag. Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 07 10月, 2008 1 次提交
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由 Eric Sandeen 提交于
ext4_ext_walk_space() was reinstated to be used for iterating over file extents with a callback; it is used by the ext4 fiemap implementation. Signed-off-by: NEric Sandeen <sandeen@redhat.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu> Cc: linux-ext4@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org
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- 10 10月, 2008 2 次提交
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由 Theodore Ts'o 提交于
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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由 Theodore Ts'o 提交于
With modern hard drives, reading 64k takes roughly the same time as reading a 4k block. So request readahead for adjacent inode table blocks to reduce the time it takes when iterating over directories (especially when doing this in htree sort order) in a cold cache case. With this patch, the time it takes to run "git status" on a kernel tree after flushing the caches via "echo 3 > /proc/sys/vm/drop_caches" is reduced by 21%. Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 14 9月, 2008 2 次提交
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由 Aneesh Kumar K.V 提交于
With delayed allocation we use i_data_sem to update i_disksize. We need to update i_disksize only if the new size specified is greater than the current value and we need to make sure we don't race with other i_disksize update. With delayed allocation we will switch to the write_begin function for non-delayed allocation if we are low on free blocks. This means the write_begin function for non-delayed allocation also needs to use the same locking. We also need to check and update i_disksize even if the new size is less that inode.i_size because of delayed allocation. Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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由 Aneesh Kumar K.V 提交于
For blocksize < pagesize we need to remove blocks that got allocated in block_write_begin() if we fail with ENOSPC for later blocks. block_write_begin() internally does this if it allocated pages locally. This makes sure we don't have blocks outside inode.i_size during ENOSPC. Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 09 9月, 2008 2 次提交
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由 Aneesh Kumar K.V 提交于
When we truncate files, the meta-data blocks released are not reused untill we commit the truncate transaction. That means delayed get_block request will return ENOSPC even if we have free blocks left. Force a journal commit and retry block allocation if we get ENOSPC with free blocks left. Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: NMingming Cao <cmm@us.ibm.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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由 Aneesh Kumar K.V 提交于
Make sure we don't add the inode to the journal handle until after the block allocation, so that a journal commit will not include the inode in case of block allocation failure. Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: NMingming Cao <cmm@us.ibm.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 09 10月, 2008 1 次提交
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由 Aneesh Kumar K.V 提交于
The delayed allocation code allocates blocks during writepages(), which can not handle block allocation failures. To deal with this, we switch away from delayed allocation mode when we are running low on free blocks. This also allows us to avoid needing to reserve a large number of meta-data blocks in case all of the requested blocks are discontiguous. Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: NMingming Cao <cmm@us.ibm.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 10 10月, 2008 1 次提交
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由 Aneesh Kumar K.V 提交于
This patch adds dirty block accounting using percpu_counters. Delayed allocation block reservation is now done by updating dirty block counter. In a later patch we switch to non delalloc mode if the filesystem free blocks is greater than 150% of total filesystem dirty blocks Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Mingming Cao<cmm@us.ibm.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 09 9月, 2008 1 次提交
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由 Aneesh Kumar K.V 提交于
During block reservation if we don't have enough blocks left, retry block reservation with smaller block counts. This makes sure we try fallocate and DIO with smaller request size and don't fail early. The delayed allocation reservation cannot try with smaller block count. So retry block reservation to handle temporary disk full conditions. Also print free blocks details if we fail block allocation during writepages. Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: NMingming Cao <cmm@us.ibm.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 09 10月, 2008 1 次提交
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由 Aneesh Kumar K.V 提交于
With delayed allocation we need to make sure block are reserved before we attempt to allocate them. Otherwise we get block allocation failure (ENOSPC) during writepages which cannot be handled. This would mean silent data loss (We do a printk stating data will be lost). This patch updates the DIO and fallocate code path to do block reservation before block allocation. This is needed to make sure parallel DIO and fallocate request doesn't take block out of delayed reserve space. When free blocks count go below a threshold we switch to a slow patch which looks at other CPU's accumulated percpu counter values. Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 20 8月, 2008 1 次提交
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由 Aneesh Kumar K.V 提交于
We are a bit agressive in invalidating all the pages. But it is ok because we really don't know why the block allocation failed and it is better to come of the writeback path so that user can look for more info. Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
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- 09 9月, 2008 1 次提交
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由 Theodore Ts'o 提交于
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 03 8月, 2008 1 次提交
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由 Eric Sandeen 提交于
The variables 'from' and 'to' are not used anywhere. Signed-off-by: NEric Sandeen <sandeen@redhat.com> Acked-by: NMingming Cao <cmm@us.ibm.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 29 7月, 2008 1 次提交
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由 Hisashi Hifumi 提交于
When we read some part of a file through pagecache, if there is a pagecache of corresponding index but this page is not uptodate, read IO is issued and this page will be uptodate. I think this is good for pagesize == blocksize environment but there is room for improvement on pagesize != blocksize environment. Because in this case a page can have multiple buffers and even if a page is not uptodate, some buffers can be uptodate. So I suggest that when all buffers which correspond to a part of a file that we want to read are uptodate, use this pagecache and copy data from this pagecache to user buffer even if a page is not uptodate. This can reduce read IO and improve system throughput. I wrote a benchmark program and got result number with this program. This benchmark do: 1: mount and open a test file. 2: create a 512MB file. 3: close a file and umount. 4: mount and again open a test file. 5: pwrite randomly 300000 times on a test file. offset is aligned by IO size(1024bytes). 6: measure time of preading randomly 100000 times on a test file. The result was: 2.6.26 330 sec 2.6.26-patched 226 sec Arch:i386 Filesystem:ext3 Blocksize:1024 bytes Memory: 1GB On ext3/4, a file is written through buffer/block. So random read/write mixed workloads or random read after random write workloads are optimized with this patch under pagesize != blocksize environment. This test result showed this. The benchmark program is as follows: #include <stdio.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <unistd.h> #include <time.h> #include <stdlib.h> #include <string.h> #include <sys/mount.h> #define LEN 1024 #define LOOP 1024*512 /* 512MB */ main(void) { unsigned long i, offset, filesize; int fd; char buf[LEN]; time_t t1, t2; if (mount("/dev/sda1", "/root/test1/", "ext3", 0, 0) < 0) { perror("cannot mount\n"); exit(1); } memset(buf, 0, LEN); fd = open("/root/test1/testfile", O_CREAT|O_RDWR|O_TRUNC); if (fd < 0) { perror("cannot open file\n"); exit(1); } for (i = 0; i < LOOP; i++) write(fd, buf, LEN); close(fd); if (umount("/root/test1/") < 0) { perror("cannot umount\n"); exit(1); } if (mount("/dev/sda1", "/root/test1/", "ext3", 0, 0) < 0) { perror("cannot mount\n"); exit(1); } fd = open("/root/test1/testfile", O_RDWR); if (fd < 0) { perror("cannot open file\n"); exit(1); } filesize = LEN * LOOP; for (i = 0; i < 300000; i++){ offset = (random() % filesize) & (~(LEN - 1)); pwrite(fd, buf, LEN, offset); } printf("start test\n"); time(&t1); for (i = 0; i < 100000; i++){ offset = (random() % filesize) & (~(LEN - 1)); pread(fd, buf, LEN, offset); } time(&t2); printf("%ld sec\n", t2-t1); close(fd); if (umount("/root/test1/") < 0) { perror("cannot umount\n"); exit(1); } } Signed-off-by: NHisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Christoph Hellwig <hch@infradead.org> Cc: Jan Kara <jack@ucw.cz> Cc: <linux-ext4@vger.kernel.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 19 8月, 2008 1 次提交
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由 Aneesh Kumar K.V 提交于
For small file block allocations, mballoc uses per cpu prealloc space. Use goal block when searching for the right prealloc space. Also make sure ext4_da_writepages tries to write all the pages for small files in single attempt Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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- 20 8月, 2008 1 次提交
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由 Mingming Cao 提交于
Previous delalloc writepages implementation started a new transaction outside of a loop which called get_block() to do the block allocation. Since we didn't know exactly how many blocks would need to be allocated, the estimated journal credits required was very conservative and caused many issues. With the reworked delayed allocation, a new transaction is created for each get_block(), thus we don't need to guess how many credits for the multiple chunk of allocation. We start every transaction with enough credits for inserting a single exent. When estimate the credits for indirect blocks to allocate a chunk of blocks, we need to know the number of data blocks to allocate. We use the total number of reserved delalloc datablocks; if that is too big, for non-extent files, we need to limit the number of blocks to EXT4_MAX_TRANS_BLOCKS. Code cleanup from Aneesh. Signed-off-by: NMingming Cao <cmm@us.ibm.com> Reviewed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
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