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path: root/drivers/md/raid10.c
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* md: add MODULE_DESCRIPTION for all md related modules.NeilBrown2009-12-13
| | | | | | Suggested by Oren Held <orenhe@il.ibm.com> Signed-off-by: NeilBrown <neilb@suse.de>
* raid: improve MD/raid10 handling of correctable read errors.Robert Becker2009-12-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We've noticed severe lasting performance degradation of our raid arrays when we have drives that yield large amounts of media errors. The raid10 module will queue each failed read for retry, and also will attempt call fix_read_error() to perform the read recovery. Read recovery is performed while the array is frozen, so repeated recovery attempts can degrade the performance of the array for extended periods of time. With this patch I propose adding a per md device max number of corrected read attempts. Each rdev will maintain a count of read correction attempts in the rdev->read_errors field (not used currently for raid10). When we enter fix_read_error() we'll check to see when the last read error occurred, and divide the read error count by 2 for every hour since the last read error. If at that point our read error count exceeds the read error threshold, we'll fail the raid device. In addition in this patch I add sysfs nodes (get/set) for the per md max_read_errors attribute, the rdev->read_errors attribute, and added some printk's to indicate when fix_read_error fails to repair an rdev. For testing I used debugfs->fail_make_request to inject IO errors to the rdev while doing IO to the raid array. Signed-off-by: Robert Becker <Rob.Becker@riverbed.com> Signed-off-by: NeilBrown <neilb@suse.de>
* md/raid10: print more useful messages on device failure.Robert Becker2009-12-13
| | | | | | | | | When we get a read error on a device in a RAID10, and attempting to repair the error fails, print more useful messages about why it failed. Signed-off-by: Robert Becker <Rob.Becker@riverbed.com> Signed-off-by: NeilBrown <neilb@suse.de>
* md: remove needless setting of thread->timeout in raid10_quiesceNeilBrown2009-12-13
| | | | | | | | | | As bitmap_create and bitmap_destroy already set thread->timeout as appropriate, there is no need to do it in raid10_quiesce. There is a possible need to wake the thread after the timeout has been set low, but it is better to do that where the timeout is actually set low, in bitmap_create. Signed-off-by: NeilBrown <neilb@suse.de>
* md: change daemon_sleep to be in 'jiffies' rather than 'seconds'.NeilBrown2009-12-13
| | | | | | This removes a lot of multiplications by HZ. Signed-off-by: NeilBrown <neilb@suse.de>
* md: move offset, daemon_sleep and chunksize out of bitmap structureNeilBrown2009-12-13
| | | | | | | ... and into bitmap_info. These are all configuration parameters that need to be set before the bitmap is created. Signed-off-by: NeilBrown <neilb@suse.de>
* md: support barrier requests on all personalities.NeilBrown2009-12-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously barriers were only supported on RAID1. This is because other levels requires synchronisation across all devices and so needed a different approach. Here is that approach. When a barrier arrives, we send a zero-length barrier to every active device. When that completes - and if the original request was not empty - we submit the barrier request itself (with the barrier flag cleared) and then submit a fresh load of zero length barriers. The barrier request itself is asynchronous, but any subsequent request will block until the barrier completes. The reason for clearing the barrier flag is that a barrier request is allowed to fail. If we pass a non-empty barrier through a striping raid level it is conceivable that part of it could succeed and part could fail. That would be way too hard to deal with. So if the first run of zero length barriers succeed, we assume all is sufficiently well that we send the request and ignore errors in the second run of barriers. RAID5 needs extra care as write requests may not have been submitted to the underlying devices yet. So we flush the stripe cache before proceeding with the barrier. Note that the second set of zero-length barriers are submitted immediately after the original request is submitted. Thus when a personality finds mddev->barrier to be set during make_request, it should not return from make_request until the corresponding per-device request(s) have been queued. That will be done in later patches. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Andre Noll <maan@systemlinux.org>
* md: raid1/raid10: handle allocation errors during array setup.NeilBrown2009-10-16
| | | | | | | | | | | | | | Both raid1 and raid10 create a mempool during startup. If the 'alloc' function for this mempool fails, unplug_slaves is called. If that happens when the pool is being initialised, unplug_slaves will try to use the 'conf' structure that isn't filled in yet, and badness will happen. So ensure that unplug_slaves doesn't get called unless we know that the conf structure if fully initialised. Signed-off-by: NeilBrown <neilb@suse.de>
* md/raid1/raid10: add a cond_reschedNeilBrown2009-10-16
| | | | | | | | | | During 'check' of a raid1 or raid10 it is possible for the management thread to spend a lot of time running 'memcmp' on blocks from different devices, so make sure the thread has a chance to schedule. raid5d already has a cond_resched (in process_stripe). Reported-By: Lee Howard <faxguy@howardsilvan.com> Signed-off-by: NeilBrown <neilb@suse.de>
* md: raid-1/10: fix RW bits manipulationDmitry Monakhov2009-09-23
| | | | | | | | | | | Recently Jens has changed bio_rw_flagged() logic by following commit 1f98a13f623e0ef666690a18c1250335fc6d7ef1. Now it returns bool instead of int. This broke raid1/raid10 RW bits manipulation logic. One of visible result is BUG_ON triggering due to empty barrier here scsi_lib.c:1108 scsi_setup_fs_cmnd() Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: NeilBrown <neilb@suse.de>
* md: report device as congested when suspendedNeilBrown2009-09-23
| | | | | | | This should writeback from coming when the device is temporarily suspended. Signed-off-by: NeilBrown <neilb@suse.de>
* md: Improve name of threads created by md_register_threadNeilBrown2009-09-23
| | | | | | | | | | | | | | The management thread for raid4,5,6 arrays are all called mdX_raid5, independent of the actual raid level, which is wrong and can be confusion. So change md_register_thread to use the name from the personality unless no alternate name (like 'resync' or 'reshape') is given. This is simpler and more correct. Cc: Jinzc <zhenchengjin@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
* md: remove sparse waring "symbol xxx shadows an earlier one"NeilBrown2009-09-23
| | | | | | | Rename some variable and remove some duplicate definitions to avoid there warnings. None of them are actual errors. Signed-off-by: NeilBrown <neilb@suse.de>
* bio: first step in sanitizing the bio->bi_rw flag testingJens Axboe2009-09-11
| | | | | | | | Get rid of any functions that test for these bits and make callers use bio_rw_flagged() directly. Then it is at least directly apparent what variable and flag they check. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* md: Push down data integrity code to personalities.Andre Noll2009-08-02
| | | | | | | | | | | | | | | | | | | | | | | | | This patch replaces md_integrity_check() by two new public functions: md_integrity_register() and md_integrity_add_rdev() which are both personality-independent. md_integrity_register() is called from the ->run and ->hot_remove methods of all personalities that support data integrity. The function iterates over the component devices of the array and determines if all active devices are integrity capable and if their profiles match. If this is the case, the common profile is registered for the mddev via blk_integrity_register(). The second new function, md_integrity_add_rdev() is called from the ->hot_add_disk methods, i.e. whenever a new device is being added to a raid array. If the new device does not support data integrity, or has a profile different from the one already registered, data integrity for the mddev is disabled. For raid0 and linear, only the call to md_integrity_register() from the ->run method is necessary. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
* md: Use new topology calls to indicate alignment and I/O sizesMartin K. Petersen2009-06-30
| | | | | | | | | | | Switch MD over to the new disk_stack_limits() function which checks for aligment and adjusts preferred I/O sizes when stacking. Also indicate preferred I/O sizes where applicable. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de>
* md: Push down reconstruction log message to personality code.Andre Noll2009-06-17
| | | | | | | | | | | | Currently, the md layer checks in analyze_sbs() if the raid level supports reconstruction (mddev->level >= 1) and if reconstruction is in progress (mddev->recovery_cp != MaxSector). Move that printk into the personality code of those raid levels that care (levels 1, 4, 5, 6, 10). Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
* md: Make mddev->chunk_size sector-based.Andre Noll2009-06-17
| | | | | | | | | | | | | This patch renames the chunk_size field to chunk_sectors with the implied change of semantics. Since is_power_of_2(chunk_size) = is_power_of_2(chunk_sectors << 9) = is_power_of_2(chunk_sectors) these bits don't need an adjustment for the shift. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
* md: raid10: chunk size check in runraz ben yehuda2009-06-16
| | | | | | | have raid10 check chunk size in run method instead of in md Signed-off-by: raziebe@gmail.com Signed-off-by: NeilBrown <neilb@suse.de>
* md: remove mddev_to_conf "helper" macroNeilBrown2009-06-16
| | | | | | | | | | Having a macro just to cast a void* isn't really helpful. I would must rather see that we are simply de-referencing ->private, than have to know what the macro does. So open code the macro everywhere and remove the pointless cast. Signed-off-by: NeilBrown <neilb@suse.de>
* block: Use accessor functions for queue limitsMartin K. Petersen2009-05-22
| | | | | | | | Convert all external users of queue limits to using wrapper functions instead of poking the request queue variables directly. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* md/raid10: don't clear bitmap during recovery if array will still be degraded.NeilBrown2009-05-06
| | | | | | | | | | | | | | | | | | If we have a raid10 with multiple missing devices, and we recover just one of these to a spare, then we risk (depending on the bitmap and array chunk size) clearing bits of the bitmap for which recovery isn't complete (because a device is still missing). This can lead to a subsequent "re-add" being recovered without any IO happening, which would result in loss of data. This patch takes the safe approach of not clearing bitmap bits if the array will still be degraded. This patch is suitable for all active -stable kernels. Cc: stable@kernel.org Signed-off-by: NeilBrown <neilb@suse.de>
* block: move bio list helpers into bio.hChristoph Hellwig2009-04-15
| | | | | | | | | It's used by DM and MD and generally useful, so move the bio list helpers into bio.h. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* md: 'array_size' sysfs attributeDan Williams2009-03-31
| | | | | | | | | | | | | | | | | | | | | | | | | Allow userspace to set the size of the array according to the following semantics: 1/ size must be <= to the size returned by mddev->pers->size(mddev, 0, 0) a) If size is set before the array is running, do_md_run will fail if size is greater than the default size b) A reshape attempt that reduces the default size to less than the set array size should be blocked 2/ once userspace sets the size the kernel will not change it 3/ writing 'default' to this attribute returns control of the size to the kernel and reverts to the size reported by the personality Also, convert locations that need to know the default size from directly reading ->array_sectors to <pers>_size. Resync/reshape operations always follow the default size. Finally, fixup other locations that read a number of 1k-blocks from userspace to use strict_blocks_to_sectors() which checks for unsigned long long to sector_t overflow and blocks to sectors overflow. Reviewed-by: Andre Noll <maan@systemlinux.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* md: centralize ->array_sectors modificationsDan Williams2009-03-30
| | | | | | | | | Get personalities out of the business of directly modifying ->array_sectors. Lays groundwork to introduce policy on when ->array_sectors can be modified. Reviewed-by: Andre Noll <maan@systemlinux.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* md: add 'size' as a personality methodDan Williams2009-03-30
| | | | | | | | | | | | | In preparation for giving userspace control over ->array_sectors we need to be able to retrieve the 'default' size, and the 'anticipated' size when a reshape is requested. For personalities that do not reshape emit a warning if anything but the default size is requested. In the raid5 case we need to update ->previous_raid_disks to make the new 'default' size available. Reviewed-by: Andre Noll <maan@systemlinux.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* md: enable suspend/resume of md devices.NeilBrown2009-03-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To be able to change the 'level' of an md/raid array, we need to suspend the device so that no requests are active - then move some pointers around etc. The code already keeps counts of active requests and the ->quiesce function can be used to wait until those counts hit zero. However the quiesce function blocks new requests once they are all ready 'inside' the personality module, and that is too late if we want to replace the personality modules. So make all md requests come in through a common md_make_request function that keeps track of how many requests have entered the modules but may not yet be on the internal reference counts. Allow md_make_request to be blocked when we want to suspend the device, and make it possible to wait for all those in-transit requests to be added to internal lists so that ->quiesce can wait for them. There is still a problem that when a request completes, we drop the ref count inside the personality code so there is a short time between when the refcount hits zero, and when the personality code is no longer being used. The personality code never blocks (schedule or spinlock) between dropping the refcount and exiting the routine, so this should be safe (as put_module calls synchronize_sched() before unmapping the module code). Signed-off-by: NeilBrown <neilb@suse.de>
* md: Make mddev->size sector-based.Andre Noll2009-03-30
| | | | | | | | | | | | | | | | | This patch renames the "size" field of struct mddev_s to "dev_sectors" and stores the number of 512-byte sectors instead of the number of 1K-blocks in it. All users of that field, including raid levels 1,4-6,10, are adjusted accordingly. This simplifies the code a bit because it allows to get rid of a couple of divisions/multiplications by two. In order to make checkpatch happy, some minor coding style issues have also been addressed. In particular, size_store() now uses strict_strtoull() instead of simple_strtoull(). Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
* md: move md_k.h from include/linux/raid/ to drivers/md/NeilBrown2009-03-30
| | | | | | It really is nicer to keep related code together.. Signed-off-by: NeilBrown <neilb@suse.de>
* md: move lots of #include lines out of .h files and into .cNeilBrown2009-03-30
| | | | | | | | | | This makes the includes more explicit, and is preparation for moving md_k.h to drivers/md/md.h Remove include/raid/md.h as its only remaining use was to #include other files. Signed-off-by: NeilBrown <neilb@suse.de>
* md: move headers out of include/linux/raid/Christoph Hellwig2009-03-30
| | | | | | | | | | Move the headers with the local structures for the disciplines and bitmap.h into drivers/md/ so that they are more easily grepable for hacking and not far away. md.h is left where it is for now as there are some uses from the outside. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: NeilBrown <neilb@suse.de>
* md: avoid races when stopping resync.NeilBrown2009-02-24
| | | | | | | | | | | | | | | | | | | | | There has been a race in raid10 and raid1 for a long time which has only recently started showing up due to a scheduler changed. When a sync_read request finishes, as soon as reschedule_retry is called, another thread can mark the resync request as having completed, so md_do_sync can finish, ->stop can be called, and ->conf can be freed. So using conf after reschedule_retry is not safe. Similarly, when finishing a sync_write, calling md_done_sync must be the last thing we do, as it allows a chain of events which will free conf and other data structures. The first of these requires action in raid10.c The second requires action in raid1.c and raid10.c Cc: stable@kernel.org Signed-off-by: NeilBrown <neilb@suse.de>
* md/raid10: Don't call bitmap_cond_end_sync when we are doing recovery.NeilBrown2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | For raid1/4/5/6, resync (fixing inconsistencies between devices) is very similar to recovery (rebuilding a failed device onto a spare). The both walk through the device addresses in order. For raid10 it can be quite different. resync follows the 'array' address, and makes sure all copies are the same. Recover walks through 'device' addresses and recreates each missing block. The 'bitmap_cond_end_sync' function allows the write-intent-bitmap (When present) to be updated to reflect a partially completed resync. It makes assumptions which mean that it does not work correctly for raid10 recovery at all. In particularly, it can cause bitmap-directed recovery of a raid10 to not recovery some of the blocks that need to be recovered. So move the call to bitmap_cond_end_sync into the resync path, rather than being in the common "resync or recovery" path. Cc: stable@kernel.org Signed-off-by: NeilBrown <neilb@suse.de>
* md/raid10: Don't skip more than 1 bitmap-chunk at a time during recovery.NeilBrown2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | When doing recovery on a raid10 with a write-intent bitmap, we only need to recovery chunks that are flagged in the bitmap. However if we choose to skip a chunk as it isn't flag, the code currently skips the whole raid10-chunk, thus it might not recovery some blocks that need recovering. This patch fixes it. In case that is confusing, it might help to understand that there is a 'raid10 chunk size' which guides how data is distributed across the devices, and a 'bitmap chunk size' which says how much data corresponds to a single bit in the bitmap. This bug only affects cases where the bitmap chunk size is smaller than the raid10 chunk size. Cc: stable@kernel.org Signed-off-by: NeilBrown <neilb@suse.de>
* md: use list_for_each_entry macro directlyCheng Renquan2009-01-08
| | | | | | | | | | | | | | | | | The rdev_for_each macro defined in <linux/raid/md_k.h> is identical to list_for_each_entry_safe, from <linux/list.h>, it should be defined to use list_for_each_entry_safe, instead of reinventing the wheel. But some calls to each_entry_safe don't really need a safe version, just a direct list_for_each_entry is enough, this could save a temp variable (tmp) in every function that used rdev_for_each. In this patch, most rdev_for_each loops are replaced by list_for_each_entry, totally save many tmp vars; and only in the other situations that will call list_del to delete an entry, the safe version is used. Signed-off-by: Cheng Renquan <crquan@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
* md: fix bug in raid10 recovery.NeilBrown2008-11-06
| | | | | | | | | | | | | | Adding a spare to a raid10 doesn't cause recovery to start. This is due to an silly type in commit 6c2fce2ef6b4821c21b5c42c7207cb9cf8c87eda and so is a bug in 2.6.27 and .28-rc. Thanks to Thomas Backlund for bisecting to find this. Cc: Thomas Backlund <tmb@mandriva.org> Cc: stable@kernel.org Signed-off-by: NeilBrown <neilb@suse.de>
* md: build failure due to missing delay.hStephen Rothwell2008-10-15
| | | | | | | | | | | | | | | | | | | | | Today's linux-next build (powerpc ppc64_defconfig) failed like this: drivers/md/raid1.c: In function 'sync_request': drivers/md/raid1.c:1759: error: implicit declaration of function 'msleep_interruptible' make[3]: *** [drivers/md/raid1.o] Error 1 make[3]: *** Waiting for unfinished jobs.... drivers/md/raid10.c: In function 'sync_request': drivers/md/raid10.c:1749: error: implicit declaration of function 'msleep_interruptible' make[3]: *** [drivers/md/raid10.o] Error 1 drivers/md/md.c: In function 'md_do_sync': drivers/md/md.c:5915: error: implicit declaration of function 'msleep' Caused by commit 6caa3b0bbdb474647f6bdd8a958ffc46f78d8d58 ("md: Remove unnecessary #includes, #defines, and function declarations"). I added the following patch. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: NeilBrown <neilb@suse.de>
* md: Relax minimum size restrictions on chunk_size.NeilBrown2008-10-12
| | | | | | | | | | | | | | | | | | Currently, the 'chunk_size' of an array must be at-least PAGE_SIZE. This makes moving an array to a machine with a larger PAGE_SIZE, or changing the kernel to use a larger PAGE_SIZE, can stop an array from working. For RAID10 and RAID4/5/6, this is non-trivial to fix as the resync process works on whole pages at a time, and assumes them to be wholly within a stripe. For other raid personalities, this restriction is not needed at all and can be dropped. So remove the test on chunk_size from common can, and add it in just the places where it is needed: raid10 and raid4/5/6. Signed-off-by: NeilBrown <neilb@suse.de>
* block: mark bio_split_pool staticDenis ChengRq2008-10-09
| | | | | | | | | | | Since all bio_split calls refer the same single bio_split_pool, the bio_split function can use bio_split_pool directly instead of the mempool_t parameter; then the mempool_t parameter can be removed from bio_split param list, and bio_split_pool is only referred in fs/bio.c file, can be marked static. Signed-off-by: Denis ChengRq <crquan@gmail.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: move stats from disk to part0Tejun Heo2008-10-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move stats related fields - stamp, in_flight, dkstats - from disk to part0 and unify stat handling such that... * part_stat_*() now updates part0 together if the specified partition is not part0. ie. part_stat_*() are now essentially all_stat_*(). * {disk|all}_stat_*() are gone. * part_round_stats() is updated similary. It handles part0 stats automatically and disk_round_stats() is killed. * part_{inc|dec}_in_fligh() is implemented which automatically updates part0 stats for parts other than part0. * disk_map_sector_rcu() is updated to return part0 if no part matches. Combined with the above changes, this makes NULL special case handling in callers unnecessary. * Separate stats show code paths for disk are collapsed into part stats show code paths. * Rename disk_stat_lock/unlock() to part_stat_lock/unlock() While at it, reposition stat handling macros a bit and add missing parentheses around macro parameters. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: fix diskstats accessTejun Heo2008-10-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are two variants of stat functions - ones prefixed with double underbars which don't care about preemption and ones without which disable preemption before manipulating per-cpu counters. It's unclear whether the underbarred ones assume that preemtion is disabled on entry as some callers don't do that. This patch unifies diskstats access by implementing disk_stat_lock() and disk_stat_unlock() which take care of both RCU (for partition access) and preemption (for per-cpu counter access). diskstats access should always be enclosed between the two functions. As such, there's no need for the versions which disables preemption. They're removed and double underbars ones are renamed to drop the underbars. As an extra argument is added, there's no danger of using the old version unconverted. disk_stat_lock() uses get_cpu() and returns the cpu index and all diskstat functions which access per-cpu counters now has @cpu argument to help RT. This change adds RCU or preemption operations at some places but also collapses several preemption ops into one at others. Overall, the performance difference should be negligible as all involved ops are very lightweight per-cpu ones. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: raid fixups for removal of bi_hw_segmentsJens Axboe2008-10-09
| | | | Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* drop vmerge accountingMikulas Patocka2008-10-09
| | | | | | | | Remove hw_segments field from struct bio and struct request. Without virtual merge accounting they have no purpose. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* Allow raid10 resync to happening in larger chunks.NeilBrown2008-08-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | The raid10 resync/recovery code currently limits the amount of in-flight resync IO to 2Meg. This was copied from raid1 where it seems quite adequate. However for raid10, some layouts require a bit of seeking to perform a resync, and allowing a larger buffer size means that the seeking can be significantly reduced. There is probably no real need to limit the amount of in-flight IO at all. Any shortage of memory will naturally reduce the amount of buffer space available down to a set minimum, and any concurrent normal IO will quickly cause resync IO to back off. The only problem would be that normal IO has to wait for all resync IO to finish, so a very large amount of resync IO could cause unpleasant latency when normal IO starts up. So: increase RESYNC_DEPTH to allow 32Meg of buffer (if memory is available) which seems to be a good amount. Also reduce the amount of memory reserved as there is no need to keep 2Meg just for resync if memory is tight. Thanks to Keld for the suggestion. Cc: Keld Jørn Simonsen <keld@dkuug.dk> Signed-off-by: NeilBrown <neilb@suse.de>
* Merge branch 'for-linus' of git://neil.brown.name/mdLinus Torvalds2008-08-01
|\ | | | | | | | | | | | | | | | | | | * 'for-linus' of git://neil.brown.name/md: md: raid10: wake up frozen array md: do not count blocked devices as spares md: do not progress the resync process if the stripe was blocked md: delay notification of 'active_idle' to the recovery thread md: fix merge error md: move async_tx_issue_pending_all outside spin_lock_irq
| * md: raid10: wake up frozen arrayArthur Jones2008-07-31
| | | | | | | | | | | | | | | | | | | | | | | | | | When rescheduling a bio in raid10, we wake up the md thread, but if the array is frozen, this will have no effect. This causes the array to remain frozen for eternity. We add a wake_up to allow the array to de-freeze. This code is nearly identical to the raid1 code, which has this fix already. Signed-off-by: Arthur Jones <ajones@riverbed.com> Signed-off-by: NeilBrown <neilb@suse.de>
* | Merge branch 'for-linus' of git://neil.brown.name/mdLinus Torvalds2008-07-21
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'for-linus' of git://neil.brown.name/md: (52 commits) md: Protect access to mddev->disks list using RCU md: only count actual openers as access which prevent a 'stop' md: linear: Make array_size sector-based and rename it to array_sectors. md: Make mddev->array_size sector-based. md: Make super_type->rdev_size_change() take sector-based sizes. md: Fix check for overlapping devices. md: Tidy up rdev_size_store a bit: md: Remove some unused macros. md: Turn rdev->sb_offset into a sector-based quantity. md: Make calc_dev_sboffset() return a sector count. md: Replace calc_dev_size() by calc_num_sectors(). md: Make update_size() take the number of sectors. md: Better control of when do_md_stop is allowed to stop the array. md: get_disk_info(): Don't convert between signed and unsigned and back. md: Simplify restart_array(). md: alloc_disk_sb(): Return proper error value. md: Simplify sb_equal(). md: Simplify uuid_equal(). md: sb_equal(): Fix misleading printk. md: Fix a typo in the comment to cmd_match(). ...
| * md: Make mddev->array_size sector-based.Andre Noll2008-07-21
| | | | | | | | | | | | | | | | | | This patch renames the array_size field of struct mddev_s to array_sectors and converts all instances to use units of 512 byte sectors instead of 1k blocks. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
| * rationalise return value for ->hot_add_disk method.Neil Brown2008-06-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For all array types but linear, ->hot_add_disk returns 1 on success, 0 on failure. For linear, it returns 0 on success and -errno on failure. This doesn't cause a functional problem because the ->hot_add_disk function of linear is used quite differently to the others. However it is confusing. So convert all to return 0 for success or -errno on failure and fix call sites to match. Signed-off-by: Neil Brown <neilb@suse.de>
| * Support adding a spare to a live md array with external metadata.Neil Brown2008-06-27
| | | | | | | | | | | | | | i.e. extend the 'md/dev-XXX/slot' attribute so that you can tell a device to fill an vacant slot in an and md array. Signed-off-by: Neil Brown <neilb@suse.de>