summaryrefslogtreecommitdiffstats
path: root/fs/xfs/xfs_buf.c
Commit message (Collapse)AuthorAgeFilesLines
...
* xfs: use kmem_zone_zalloc for buffersDave Chinner2012-05-141-2/+1Star
| | | | | | | | | To replace the alloc/memset pair. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: fix incorrect b_offset initialisationDave Chinner2012-05-141-1/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | Because we no longer use the page cache for buffering, there is no direct block number to page offset relationship anymore. xfs_buf_get_pages is still setting up b_offset as if there was some relationship, and that is leading to incorrectly setting up *uncached* buffers that don't overwrite b_offset once they've had pages allocated. For cached buffers, the first block of the buffer is always at offset zero into the allocated memory. This is true for sub-page sized buffers, as well as for multiple-page buffers. For uncached buffers, b_offset is only non-zero when we are associating specific memory to the buffers, and that is set correctly by the code setting up the buffer. Hence remove the setting of b_offset in xfs_buf_get_pages, because it is now always the wrong thing to do. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: check for buffer errors before waitingDave Chinner2012-05-141-12/+10Star
| | | | | | | | | | | | | | | | | | If we call xfs_buf_iowait() on a buffer that failed dispatch due to an IO error, it will wait forever for an Io that does not exist. This is hndled in xfs_buf_read, but there is other code that calls xfs_buf_iowait directly that doesn't. Rather than make the call sites have to handle checking for dispatch errors and then checking for completion errors, make xfs_buf_iowait() check for dispatch errors on the buffer before waiting. This means we handle both dispatch and completion errors with one set of error handling at the caller sites. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: fix buffer lookup race on allocation failureDave Chinner2012-05-141-7/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | When memory allocation fails to add the page array or tht epages to a buffer during xfs_buf_get(), the buffer is left in the cache in a partially initialised state. There is enough state left for the next lookup on that buffer to find the buffer, and for the buffer to then be used without finishing the initialisation. As a result, when an attempt to do IO on the buffer occurs, it fails with EIO because there are no pages attached to the buffer. We cannot remove the buffer from the cache immediately and free it, because there may already be a racing lookup that is blocked on the buffer lock. Hence the moment we unlock the buffer to then free it, the other user is woken and we have a use-after-free situation. To avoid this race condition altogether, allocate the pages for the buffer before we insert it into the cache. This then means that we don't have an allocation failure case to deal after the buffer is already present in the cache, and hence avoid the problem altogether. In most cases we won't have racing inserts for the same buffer, and so won't increase the memory pressure allocation before insertion may entail. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: on-stack delayed write buffer listsChristoph Hellwig2012-05-141-210/+131Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Queue delwri buffers on a local on-stack list instead of a per-buftarg one, and write back the buffers per-process instead of by waking up xfsbufd. This is now easily doable given that we have very few places left that write delwri buffers: - log recovery: Only done at mount time, and already forcing out the buffers synchronously using xfs_flush_buftarg - quotacheck: Same story. - dquot reclaim: Writes out dirty dquots on the LRU under memory pressure. We might want to look into doing more of this via xfsaild, but it's already more optimal than the synchronous inode reclaim that writes each buffer synchronously. - xfsaild: This is the main beneficiary of the change. By keeping a local list of buffers to write we reduce latency of writing out buffers, and more importably we can remove all the delwri list promotions which were hitting the buffer cache hard under sustained metadata loads. The implementation is very straight forward - xfs_buf_delwri_queue now gets a new list_head pointer that it adds the delwri buffers to, and all callers need to eventually submit the list using xfs_buf_delwi_submit or xfs_buf_delwi_submit_nowait. Buffers that already are on a delwri list are skipped in xfs_buf_delwri_queue, assuming they already are on another delwri list. The biggest change to pass down the buffer list was done to the AIL pushing. Now that we operate on buffers the trylock, push and pushbuf log item methods are merged into a single push routine, which tries to lock the item, and if possible add the buffer that needs writeback to the buffer list. This leads to much simpler code than the previous split but requires the individual IOP_PUSH instances to unlock and reacquire the AIL around calls to blocking routines. Given that xfsailds now also handle writing out buffers, the conditions for log forcing and the sleep times needed some small changes. The most important one is that we consider an AIL busy as long we still have buffers to push, and the other one is that we do increment the pushed LSN for buffers that are under flushing at this moment, but still count them towards the stuck items for restart purposes. Without this we could hammer on stuck items without ever forcing the log and not make progress under heavy random delete workloads on fast flash storage devices. [ Dave Chinner: - rebase on previous patches. - improved comments for XBF_DELWRI_Q handling - fix XBF_ASYNC handling in queue submission (test 106 failure) - rename delwri submit function buffer list parameters for clarity - xfs_efd_item_push() should return XFS_ITEM_PINNED ] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: use per-filesystem I/O completion workqueuesChristoph Hellwig2012-03-051-17/+0Star
| | | | | | | | | | | | | | | | The new concurrency managed workqueues are cheap enough that we can create per-filesystem instead of global workqueues. This allows us to remove the trylock or defer scheme on the ilock, which is not helpful once we have outstanding log reservations until finishing a size update. Also allow the default concurrency on this workqueues so that I/O completions blocking on the ilock for one inode do not block process for another inode. Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2012-01-081-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (53 commits) Kconfig: acpi: Fix typo in comment. misc latin1 to utf8 conversions devres: Fix a typo in devm_kfree comment btrfs: free-space-cache.c: remove extra semicolon. fat: Spelling s/obsolate/obsolete/g SCSI, pmcraid: Fix spelling error in a pmcraid_err() call tools/power turbostat: update fields in manpage mac80211: drop spelling fix types.h: fix comment spelling for 'architectures' typo fixes: aera -> area, exntension -> extension devices.txt: Fix typo of 'VMware'. sis900: Fix enum typo 'sis900_rx_bufer_status' decompress_bunzip2: remove invalid vi modeline treewide: Fix comment and string typo 'bufer' hyper-v: Update MAINTAINERS treewide: Fix typos in various parts of the kernel, and fix some comments. clockevents: drop unknown Kconfig symbol GENERIC_CLOCKEVENTS_MIGR gpio: Kconfig: drop unknown symbol 'CS5535_GPIO' leds: Kconfig: Fix typo 'D2NET_V2' sound: Kconfig: drop unknown symbol ARCH_CLPS7500 ... Fix up trivial conflicts in arch/powerpc/platforms/40x/Kconfig (some new kconfig additions, close to removed commented-out old ones)
| * treewide: Fix comment and string typo 'bufer'Paul Bolle2011-12-061-1/+1
| | | | | | | | | | Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | Merge branch 'pm-for-linus' of ↵Linus Torvalds2012-01-081-1/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm * 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (76 commits) PM / Hibernate: Implement compat_ioctl for /dev/snapshot PM / Freezer: fix return value of freezable_schedule_timeout_killable() PM / shmobile: Allow the A4R domain to be turned off at run time PM / input / touchscreen: Make st1232 use device PM QoS constraints PM / QoS: Introduce dev_pm_qos_add_ancestor_request() PM / shmobile: Remove the stay_on flag from SH7372's PM domains PM / shmobile: Don't include SH7372's INTCS in syscore suspend/resume PM / shmobile: Add support for the sh7372 A4S power domain / sleep mode PM: Drop generic_subsys_pm_ops PM / Sleep: Remove forward-only callbacks from AMBA bus type PM / Sleep: Remove forward-only callbacks from platform bus type PM: Run the driver callback directly if the subsystem one is not there PM / Sleep: Make pm_op() and pm_noirq_op() return callback pointers PM/Devfreq: Add Exynos4-bus device DVFS driver for Exynos4210/4212/4412. PM / Sleep: Merge internal functions in generic_ops.c PM / Sleep: Simplify generic system suspend callbacks PM / Hibernate: Remove deprecated hibernation snapshot ioctls PM / Sleep: Fix freezer failures due to racy usermodehelper_is_disabled() ARM: S3C64XX: Implement basic power domain support PM / shmobile: Use common always on power domain governor ... Fix up trivial conflict in fs/xfs/xfs_buf.c due to removal of unused XBT_FORCE_SLEEP bit
| * | freezer: unexport refrigerator() and update try_to_freeze() slightlyTejun Heo2011-11-211-1/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is no reason to export two functions for entering the refrigerator. Calling refrigerator() instead of try_to_freeze() doesn't save anything noticeable or removes any race condition. * Rename refrigerator() to __refrigerator() and make it return bool indicating whether it scheduled out for freezing. * Update try_to_freeze() to return bool and relay the return value of __refrigerator() if freezing(). * Convert all refrigerator() users to try_to_freeze(). * Update documentation accordingly. * While at it, add might_sleep() to try_to_freeze(). Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Samuel Ortiz <samuel@sortiz.org> Cc: Chris Mason <chris.mason@oracle.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jan Kara <jack@suse.cz> Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp> Cc: Christoph Hellwig <hch@infradead.org>
* / xfs: remove unused XBT_FORCE_SLEEP bitEric Sandeen2011-12-161-5/+1Star
|/ | | | | | | | | | XBT_FORCE_SLEEP is no longer ever tested; it is only set and cleared. Remove it. Signed-off-by: Eric Sandeen <sandeen@sandeen.net> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: do not flush data workqueues in xfs_flush_buftargChristoph Hellwig2011-10-121-10/+1Star
| | | | | | | | | | | | | When we call xfs_flush_buftarg (generally from sync or umount) it already is too late to flush the data workqueues, as I/O completion is signalled for them and we are thus already done with the data we would flush here. There are places where flushing them might be useful, but the current sync interface doesn't give us that opportunity. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
* xfs: remove xfs_buf_target_nameChristoph Hellwig2011-10-121-1/+5
| | | | | | | | | | | The calling convention that returns a pointer to a static buffer is fairly nasty, so just opencode it in the only caller that is left. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
* xfs: clean up xfs_ioerror_alertChristoph Hellwig2011-10-121-0/+11
| | | | | | | | | | | | | | | | | Instead of passing the block number and mount structure explicitly get them off the bp and fix make the argument order more natural. Also move it to xfs_buf.c and stop printing the device name given that we already get the fs name as part of xfs_alert, and we know what device is operates on because of the caller that gets printed, finally rename it to xfs_buf_ioerror_alert and pass __func__ as argument where it makes sense. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
* xfs: clean up buffer allocationChristoph Hellwig2011-10-121-32/+18Star
| | | | | | | | | | | | Change _xfs_buf_initialize to allocate the buffer directly and rename it to xfs_buf_alloc now that is the only buffer allocation routine. Also remove the xfs_buf_deallocate wrapper around the kmem_zone_free calls for buffers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
* xfs: remove buffers from the delwri list in xfs_buf_staleChristoph Hellwig2011-10-121-2/+1Star
| | | | | | | | | | | | | | For each call to xfs_buf_stale we call xfs_buf_delwri_dequeue either directly before or after it, or are guaranteed by the surrounding conditionals that we are never called on delwri buffers. Simply this situation by moving the call to xfs_buf_delwri_dequeue into xfs_buf_stale. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
* xfs: remove XFS_BUF_STALE and XFS_BUF_SUPER_STALEChristoph Hellwig2011-10-121-2/+2
| | | | | | | | Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
* xfs: remove XFS_BUF_FINISH_IOWAITChristoph Hellwig2011-10-121-1/+1
| | | | | | | | Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
* xfs: remove xfs_get_buftarg_listChristoph Hellwig2011-10-121-8/+0Star
| | | | | | | | | | The code is unused and under a config option that doesn't exist, remove it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
* xfs: Don't allocate new buffers on every call to _xfs_buf_findDave Chinner2011-10-121-20/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Stats show that for an 8-way unlink @ ~80,000 unlinks/s we are doing ~1 million cache hit lookups to ~3000 buffer creates. That's almost 3 orders of magnitude more cahce hits than misses, so optimising for cache hits is quite important. In the cache hit case, we do not need to allocate a new buffer in case of a cache miss, so we are effectively hitting the allocator for no good reason for vast the majority of calls to _xfs_buf_find. 8-way create workloads are showing similar cache hit/miss ratios. The result is profiles that look like this: samples pcnt function DSO _______ _____ _______________________________ _________________ 1036.00 10.0% _xfs_buf_find [kernel.kallsyms] 582.00 5.6% kmem_cache_alloc [kernel.kallsyms] 519.00 5.0% __memcpy [kernel.kallsyms] 468.00 4.5% __ticket_spin_lock [kernel.kallsyms] 388.00 3.7% kmem_cache_free [kernel.kallsyms] 331.00 3.2% xfs_log_commit_cil [kernel.kallsyms] Further, there is a fair bit of work involved in initialising a new buffer once a cache miss has occurred and we currently do that under the rbtree spinlock. That increases spinlock hold time on what are heavily used trees. To fix this, remove the initialisation of the buffer from _xfs_buf_find() and only allocate the new buffer once we've had a cache miss. Initialise the buffer immediately after allocating it in xfs_buf_get, too, so that is it ready for insert if we get another cache miss after allocation. This minimises lock hold time and avoids unnecessary allocator churn. The resulting profiles look like: samples pcnt function DSO _______ _____ ___________________________ _________________ 8111.00 9.1% _xfs_buf_find [kernel.kallsyms] 4380.00 4.9% __memcpy [kernel.kallsyms] 4341.00 4.8% __ticket_spin_lock [kernel.kallsyms] 3401.00 3.8% kmem_cache_alloc [kernel.kallsyms] 2856.00 3.2% xfs_log_commit_cil [kernel.kallsyms] 2625.00 2.9% __kmalloc [kernel.kallsyms] 2380.00 2.7% kfree [kernel.kallsyms] 2016.00 2.3% kmem_cache_free [kernel.kallsyms] Showing a significant reduction in time spent doing allocation and freeing from slabs (kmem_cache_alloc and kmem_cache_free). Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
* xfs: Fix the incorrect comment in the header of _xfs_buf_findChandra Seetharaman2011-10-121-4/+1Star
| | | | | | | | | Fix the incorrect comment in the header of the function _xfs_buf_find(). Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com> Signed-off-by: Alex Elder <aelder@sgi.com>
* xfs: use the "delwri" terminology consistentlyChristoph Hellwig2011-10-121-24/+19Star
| | | | | | | | | | | And also remove the strange local lock and delwri list pointers in a few functions. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
* xfs: let xfs_bwrite callers handle the xfs_buf_relseChristoph Hellwig2011-10-121-4/+4
| | | | | | | | | | | | | | Remove the xfs_buf_relse from xfs_bwrite and let the caller handle it to mirror the delwri and read paths. Also remove the mount pointer passed to xfs_bwrite, which is superflous now that we have a mount pointer in the buftarg. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
* xfs: call xfs_buf_delwri_queue directlyChristoph Hellwig2011-10-121-18/+3Star
| | | | | | | | | | | | | | | | Unify the ways we add buffers to the delwri queue by always calling xfs_buf_delwri_queue directly. The xfs_bdwrite functions is removed and opencoded in its callers, and the two places setting XBF_DELWRI while a buffer is locked and expecting xfs_buf_unlock to pick it up are converted to call xfs_buf_delwri_queue directly, too. Also replace the XFS_BUF_UNDELAYWRITE macro with direct calls to xfs_buf_delwri_dequeue to make the explicit queuing/dequeuing more obvious. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
* xfs: move more delwri setup into xfs_buf_delwri_queueChristoph Hellwig2011-10-121-19/+12Star
| | | | | | | | | | | | | | | Do not transfer a reference held by the caller to the buffer on the list, or decrement it in xfs_buf_delwri_queue, but instead grab a new reference if needed, and let the caller drop its own reference. Also move setting of the XBF_DELWRI and XBF_ASYNC flags into xfs_buf_delwri_queue, and only do it if needed. Note that for now xfs_buf_unlock already has XBF_DELWRI, but that will change in the following patches. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
* xfs: remove the unlock argument to xfs_buf_delwri_queueChristoph Hellwig2011-10-121-10/+6Star
| | | | | | | | | | | | We can just unlock the buffer in the caller, and the decrement of b_hold would also be needed in the !unlock, we just never hit that case currently given that the caller handles that case. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
* xfs: remove delwri buffer handling from xfs_buf_iorequestChristoph Hellwig2011-10-121-7/+2Star
| | | | | | | | | | | | | We cannot ever reach xfs_buf_iorequest for a buffer with XBF_DELWRI set, given that all write handlers make sure that the buffer is remove from the delwri queue before, and we never do reads with the XBF_DELWRI flag set (which the code would not handle correctly anyway). Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
* xfs: remove subdirectoriesChristoph Hellwig2011-08-121-0/+1876
Use the move from Linux 2.6 to Linux 3.x as an excuse to kill the annoying subdirectories in the XFS source code. Besides the large amount of file rename the only changes are to the Makefile, a few files including headers with the subdirectory prefix, and the binary sysctl compat code that includes a header under fs/xfs/ from kernel/. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>