linux/block/blk-exec.c, branch v3.12.14

If the queue is dying then we only call the rq->end_io callout.

2013-09-18T14:33:55Z

This leaves bios setup on the request, because the caller assumes when the blk_execute_rq_nowait/blk_execute_rq call has completed that the rq->bios have been cleaned up. This patch has blk_execute_rq_nowait use __blk_end_request_all to free bios and also call rq->end_io. Signed-off-by: Mike Christie Signed-off-by: Jens Axboe

Merge branch 'for-3.9/core' of git://git.kernel.dk/linux-block

2013-02-28T20:52:24Z

Pull block IO core bits from Jens Axboe: "Below are the core block IO bits for 3.9. It was delayed a few days since my workstation kept crashing every 2-8h after pulling it into current -git, but turns out it is a bug in the new pstate code (divide by zero, will report separately). In any case, it contains: - The big cfq/blkcg update from Tejun and and Vivek. - Additional block and writeback tracepoints from Tejun. - Improvement of the should sort (based on queues) logic in the plug flushing. - _io() variants of the wait_for_completion() interface, using io_schedule() instead of schedule() to contribute to io wait properly. - Various little fixes. You'll get two trivial merge conflicts, which should be easy enough to fix up" Fix up the trivial conflicts due to hlist traversal cleanups (commit b67bfe0d42ca: "hlist: drop the node parameter from iterators"). * 'for-3.9/core' of git://git.kernel.dk/linux-block: (39 commits) block: remove redundant check to bd_openers() block: use i_size_write() in bd_set_size() cfq: fix lock imbalance with failed allocations drivers/block/swim3.c: fix null pointer dereference block: don't select PERCPU_RWSEM block: account iowait time when waiting for completion of IO request sched: add wait_for_completion_io[_timeout] writeback: add more tracepoints block: add block_{touch|dirty}_buffer tracepoint buffer: make touch_buffer() an exported function block: add @req to bio_{front|back}_merge tracepoints block: add missing block_bio_complete() tracepoint block: Remove should_sort judgement when flush blk_plug block,elevator: use new hashtable implementation cfq-iosched: add hierarchical cfq_group statistics cfq-iosched: collect stats from dead cfqgs cfq-iosched: separate out cfqg_stats_reset() from cfq_pd_reset_stats() blkcg: make blkcg_print_blkgs() grab q locks instead of blkcg lock block: RCU free request_queue blkcg: implement blkg_[rw]stat_recursive_sum() and blkg_[rw]stat_merge() ...

block: account iowait time when waiting for completion of IO request

2013-02-15T15:45:07Z

Using wait_for_completion() for waiting for a IO request to be executed results in wrong iowait time accounting. For example, a system having the only task doing write() and fdatasync() on a block device can be reported being idle instead of iowaiting as it should because blkdev_issue_flush() calls wait_for_completion() which in turn calls schedule() that does not increment the iowait proc counter and thus does not turn on iowait time accounting. The patch makes block layer use wait_for_completion_io() instead of wait_for_completion() where appropriate to account iowait time correctly. Signed-off-by: Vladimir Davydov Signed-off-by: Jens Axboe

sched: Move sched.h sysctl bits into separate header

2013-02-07T19:50:54Z

Move the sysctl-related bits from include/linux/sched.h into a new file: include/linux/sched/sysctl.h. Then update source files requiring access to those bits by including the new header file. Signed-off-by: Clark Williams Cc: Peter Zijlstra Cc: Steven Rostedt Link: http://lkml.kernel.org/r/20130207094659.06dced96@riff.lan Signed-off-by: Ingo Molnar

Merge branch 'for-3.8/core' of git://git.kernel.dk/linux-block

2012-12-17T16:27:23Z

Pull block layer core updates from Jens Axboe: "Here are the core block IO bits for 3.8. The branch contains: - The final version of the surprise device removal fixups from Bart. - Don't hide EFI partitions under advanced partition types. It's fairly wide spread these days. This is especially dangerous for systems that have both msdos and efi partition tables, where you want to keep them in sync. - Cleanup of using -1 instead of the proper NUMA_NO_NODE - Export control of bdi flusher thread CPU mask and default to using the home node (if known) from Jeff. - Export unplug tracepoint for MD. - Core improvements from Shaohua. Reinstate the recursive merge, as the original bug has been fixed. Add plugging for discard and also fix a problem handling non pow-of-2 discard limits. There's a trivial merge in block/blk-exec.c due to a fix that went into 3.7-rc at a later point than -rc4 where this is based." * 'for-3.8/core' of git://git.kernel.dk/linux-block: block: export block_unplug tracepoint block: add plug for blkdev_issue_discard block: discard granularity might not be power of 2 deadline: Allow 0ms deadline latency, increase the read speed partitions: enable EFI/GPT support by default bsg: Remove unused function bsg_goose_queue() block: Make blk_cleanup_queue() wait until request_fn finished block: Avoid scheduling delayed work on a dead queue block: Avoid that request_fn is invoked on a dead queue block: Let blk_drain_queue() caller obtain the queue lock block: Rename queue dead flag bdi: add a user-tunable cpu_list for the bdi flusher threads block: use NUMA_NO_NODE instead of -1 block: recursive merge requests block CFQ: avoid moving request to different queue

block: Avoid that request_fn is invoked on a dead queue

2012-12-06T13:32:01Z

A block driver may start cleaning up resources needed by its request_fn as soon as blk_cleanup_queue() finished, so request_fn must not be invoked after draining finished. This is important when blk_run_queue() is invoked without any requests in progress. As an example, if blk_drain_queue() and scsi_run_queue() run in parallel, blk_drain_queue() may have finished all requests after scsi_run_queue() has taken a SCSI device off the starved list but before that last function has had a chance to run the queue. Signed-off-by: Bart Van Assche Cc: James Bottomley Cc: Mike Christie Cc: Chanho Min Acked-by: Tejun Heo Signed-off-by: Jens Axboe

block: Rename queue dead flag

2012-12-06T13:30:58Z

QUEUE_FLAG_DEAD is used to indicate that queuing new requests must stop. After this flag has been set queue draining starts. However, during the queue draining phase it is still safe to invoke the queue's request_fn, so QUEUE_FLAG_DYING is a better name for this flag. This patch has been generated by running the following command over the kernel source tree: git grep -lEw 'blk_queue_dead|QUEUE_FLAG_DEAD' | xargs sed -i.tmp -e 's/blk_queue_dead/blk_queue_dying/g' \ -e 's/QUEUE_FLAG_DEAD/QUEUE_FLAG_DYING/g'; \ sed -i.tmp -e "s/QUEUE_FLAG_DYING$(printf \\t)*5/QUEUE_FLAG_DYING$(printf \\t)5/g" \ include/linux/blkdev.h; \ sed -i.tmp -e 's/ DEAD/ DYING/g' -e 's/dead queue/a dying queue/' \ -e 's/Dead queue/A dying queue/' block/blk-core.c Signed-off-by: Bart Van Assche Acked-by: Tejun Heo Cc: James Bottomley Cc: Mike Christie Cc: Jens Axboe Cc: Chanho Min Signed-off-by: Jens Axboe

block: Don't access request after it might be freed

2012-11-23T13:32:55Z

After we've done __elv_add_request() and __blk_run_queue() in blk_execute_rq_nowait(), the request might finish and be freed immediately. Therefore checking if the type is REQ_TYPE_PM_RESUME isn't safe afterwards, because if it isn't, rq might be gone. Instead, check beforehand and stash the result in a temporary. This fixes crashes in blk_execute_rq_nowait() I get occasionally when running with lots of memory debugging options enabled -- I think this race is usually harmless because the window for rq to be reallocated is so small. Signed-off-by: Roland Dreier Cc: stable@kernel.org Signed-off-by: Jens Axboe

[SCSI] block: Fix blk_execute_rq_nowait() dead queue handling

2012-07-20T07:58:39Z

If the queue is dead blk_execute_rq_nowait() doesn't invoke the done() callback function. That will result in blk_execute_rq() being stuck in wait_for_completion(). Avoid this by initializing rq->end_io to the done() callback before we check the queue state. Also, make sure the queue lock is held around the invocation of the done() callback. Found this through source code review. Signed-off-by: Muthukumar Ratty Signed-off-by: Bart Van Assche Reviewed-by: Tejun Heo Acked-by: Jens Axboe Signed-off-by: James Bottomley

block: add missing blk_queue_dead() checks

2011-12-13T23:33:37Z

blk_insert_cloned_request(), blk_execute_rq_nowait() and blk_flush_plug_list() either didn't check whether the queue was dead or did it without holding queue_lock. Update them so that dead state is checked while holding queue_lock. AFAICS, this plugs all holes (requeue doesn't matter as the request is transitioning atomically from in_flight to queued). Signed-off-by: Tejun Heo Signed-off-by: Jens Axboe