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path: root/drivers/block/ll_rw_blk.c
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2005-06-28[PATCH] ll_rw_blk: prevent huge request allocationsJens Axboe
Currently we cap request allocations at q->nr_requests, but we allow a batching io context to allocate up to 32 more (default setting). This can flood the queue with request allocations, with only a few batching processes. The real fix would be to limit the number of batchers, but as that isn't currently tracked, I suggest we just cap the maximum number of allocated requests to eg 50% over the limit. This was observed in real life, users typically see this as vmstat bo numbers going off the wall with seconds of no queueing afterwards. Behaviour this bursty is not beneficial. Signed-off-by: Jens Axboe <axboe@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-27[PATCH] Update cfq io scheduler to time sliced designJens Axboe
This updates the CFQ io scheduler to the new time sliced design (cfq v3). It provides full process fairness, while giving excellent aggregate system throughput even for many competing processes. It supports io priorities, either inherited from the cpu nice value or set directly with the ioprio_get/set syscalls. The latter closely mimic set/getpriority. This import is based on my latest from -mm. Signed-off-by: Jens Axboe <axboe@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25[PATCH] ll_merge_requests_fn() cleanupNikita Danilov
ll_merge_requests_fn() assigns total_{phys,hw}_segments twice. Fix this and a typo. Signed-off-by: Nikita Danilov <nikita@clusterfs.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25[PATCH] drivers/block/ll_rw_blk.c: cleanupsAdrian Bunk
This patch contains the following cleanups: - make needlessly global code static - remove the following unused global functions: - blkdev_scsi_issue_flush_fn - __blk_attempt_remerge - remove the following unused EXPORT_SYMBOL's: - blk_phys_contig_segment - blk_hw_contig_segment - blkdev_scsi_issue_flush_fn - __blk_attempt_remerge Signed-off-by: Adrian Bunk <bunk@stusta.de> Acked-by: Jens Axboe <axboe@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23[PATCH] blk: unplug laterNick Piggin
get_request_wait needn't unplug the device immediately. Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Jens Axboe <axboe@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23[PATCH] blk: branch hintsNick Piggin
Sprinkle around a few branch hints in the block layer. Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Jens Axboe <axboe@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23[PATCH] blk: no memory barrierNick Piggin
This memory barrier is not needed because the waitqueue will only get waiters on it in the following situations: rq->count has exceeded the threshold - however all manipulations of ->count are performed under the runqueue lock, and so we will correctly pick up any waiter. Memory allocation for the request fails. In this case, there is no additional help provided by the memory barrier. We are guaranteed to eventually wake up waiters because the request allocation mempool guarantees that if the mem allocation for a request fails, there must be some requests in flight. They will wake up waiters when they are retired. Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Jens Axboe <axboe@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23[PATCH] blk: cleanup generic tag support error messagesTejun Heo
Add KERN_ERR and __FUNCTION__ to generic tag error messages, and add a comment in blk_queue_end_tag() which explains the silent failure path. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Jens Axboe <axboe@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23[PATCH] blk: remove BLK_TAGS_{PER_LONG|MASK}Tejun Heo
Replace BLK_TAGS_PER_LONG with BITS_PER_LONG and remove unused BLK_TAGS_MASK. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Jens Axboe <axboe@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23[PATCH] blk: remove blk_queue_tag->real_max_depth optimizationTejun Heo
blk_queue_tag->real_max_depth was used to optimize out unnecessary allocations/frees on tag resize. However, the whole thing was very broken - tag_map was never allocated to real_max_depth resulting in access beyond the end of the map, bits in [max_depth..real_max_depth] were set when initializing a map and copied when resizing resulting in pre-occupied tags. As the gain of the optimization is very small, well, almost nill, remove the whole thing. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Jens Axboe <axboe@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23[PATCH] blk: use find_first_zero_bit() in blk_queue_start_tag()Tejun Heo
blk_queue_start_tag() hand-coded searching for the first zero bit in the tag map. Replace it with find_first_zero_bit(). With this patch, blk_queue_star_tag() doesn't need to fill remains of tag map with 1, thus allowing it to work properly with the next remove_real_max_depth patch. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Jens Axboe <axboe@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23[PATCH] NUMA aware block device control structure allocationChristoph Lameter
Patch to allocate the control structures for for ide devices on the node of the device itself (for NUMA systems). The patch depends on the Slab API change patch by Manfred and me (in mm) and the pcidev_to_node patch that I posted today. Does some realignment too. Signed-off-by: Justin M. Forbes <jmforbes@linuxtx.org> Signed-off-by: Christoph Lameter <christoph@lameter.com> Signed-off-by: Pravin Shelar <pravin@calsoftinc.com> Signed-off-by: Shobhit Dayal <shobhit@calsoftinc.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-20[PATCH] sysfs: (driver/block) if show/store is missing return -EIODmitry Torokhov
sysfs: fix drivers/block so if an attribute doesn't implement show or store method read/write will return -EIO instead of 0 or -EINVAL. Signed-off-by: Dmitry Torokhov <dtor@mail.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-20[SCSI] remove requeue feature from blk_insert_request()Tejun Heo
blk_insert_request() has a unobivous feature of requeuing a request setting REQ_SPECIAL|REQ_SOFTBARRIER. SCSI midlayer was the only user and as previous patches removed the usage, remove the feature from blk_insert_request(). Only special requests should be queued with blk_insert_request(). All requeueing should go through blk_requeue_request(). Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-04-16[PATCH] fix NMI lockup with CFQ scheduler
The current problem seen is that the queue lock is actually in the SCSI device structure, so when that structure is freed on device release, we go boom if the queue tries to access the lock again. The fix here is to move the lock from the scsi_device to the queue. Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-04-16[PATCH] use cheaper elv_queue_empty when unplug a deviceKen Chen
In function __generic_unplug_device(), kernel can use a cheaper function elv_queue_empty() instead of more expensive elv_next_request to find whether the queue is empty or not. blk_run_queue can also made conditional on whether queue's emptiness before calling request_fn(). Signed-off-by: Jens Axboe <axboe@suse.de> Signed-off-by: Ken Chen <kenneth.w.chen@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16[PATCH] possible use-after-free of bioJens Axboe
There is a possibility that a bio will be accessed after it has been freed on SCSI. It happens if you submit a bio with BIO_SYNC marked and the auto-unplugging kicks the request_fn, SCSI re-enables interrupts in-between so if the request completes between the add_request() in __make_request() and the bio_sync() call, we could be looking at a dead bio. It's a slim race, but it has been triggered in the Real World. So assign bio_sync() to a local variable instead. Signed-off-by: Jens Axboe <axboe@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!