- Oct 21, 2021
-
-
Jackie Liu authored
We switched to directly use dev_t to get block device, lookup changed the meaning of use, now we fix this conflicting comment. Fixes: 4e7b5671 ("block: remove i_bdev") Cc: Jens Axboe <axboe@kernel.dk> Cc: Christoph Hellwig <hch@lst.de> Cc: linux-fsdevel@vger.kernel.org Signed-off-by:
Jackie Liu <liuyun01@kylinos.cn> Reviewed-by:
Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211021071344.1600362-1-liu.yun@linux.dev Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
John Garry authored
Since it is now possible for a tagset to share a single set of tags, the iter function should not re-iter the tags for the count of #hw queues in that case. Rather it should just iter once. Fixes: e155b0c2 ("blk-mq: Use shared tags for shared sbitmap support") Reported-by:
Kashyap Desai <kashyap.desai@broadcom.com> Signed-off-by:
John Garry <john.garry@huawei.com> Reviewed-by:
Ming Lei <ming.lei@redhat.com> Tested-by:
Kashyap Desai <kashyap.desai@broadcom.com> Link: https://lore.kernel.org/r/1634550083-202815-1-git-send-email-john.garry@huawei.com Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
- Oct 20, 2021
-
-
Christoph Hellwig authored
Consolidate the various helpers into a single blk_flush_plug helper that takes a plk_plug and the from_scheduler bool and switch all callsites to call it directly. Checks that the plug is non-NULL must be performed by the caller, something that most already do anyway. Signed-off-by:
Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211020144119.142582-5-hch@lst.de Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Pavel Begunkov authored
Don't call flush_plug_callbacks if there are no plug callbacks. Signed-off-by:
Pavel Begunkov <asml.silence@gmail.com> [hch: split from a larger patch] Signed-off-by:
Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211020144119.142582-4-hch@lst.de Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Christoph Hellwig authored
This helper is internal to the block layer. Signed-off-by:
Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211020144119.142582-3-hch@lst.de Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Christoph Hellwig authored
Replace the call to blk_flush_plug_list in blk_mq_submit_bio with a direct call to blk_mq_flush_plug_list. This means we do not flush plug callback from stackable devices, which doesn't really help with the accumulated requests anyway, and it also means the cached requests aren't freed here as they can still be used later on. Signed-off-by:
Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211020144119.142582-2-hch@lst.de Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
This check is meant to catch cases where a requeue is attempted on a request that is still inserted. It's never really been useful to catch any misuse, and now it's actively wrong. Outside of that, this should not be a BUG_ON() to begin with. Remove the check as it's now causing active harm, as requeue off the plug path will trigger it even though the request state is just fine. Reported-by:
Yi Zhang <yi.zhang@redhat.com> Link: https://lore.kernel.org/linux-block/CAHj4cs80zAUc2grnCZ015-2Rvd-=gXRfB_dFKy=RTm+wRo09HQ@mail.gmail.com/ Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Pavel Begunkov authored
Inline BIO_NO_PAGE_REF check of bio_release_pages() to avoid function call. Signed-off-by:
Pavel Begunkov <asml.silence@gmail.com> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Pavel Begunkov authored
percpu_ref_put() are inlined for performance and bloat the binary, we don't care about the fail case of blk_try_enter_queue(), so we can replace it with a call to blk_queue_exit(). Reviewed-by:
Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Pavel Begunkov <asml.silence@gmail.com> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Pavel Begunkov authored
First, get rid of an extra branch and chain error checks. Also reshuffle it with bio_advance(), so it goes closer to the final check, with that the compiler loads rq->rq_flags only once, and also doesn't reload bio->bi_iter.bi_size if bio_advance() didn't actually advanced the iter. Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Pavel Begunkov <asml.silence@gmail.com> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Pavel Begunkov authored
Convert bdev->bd_disk->queue to bdev_get_queue(), which is faster. Apparently, there are a few such spots in block that got lost during rebases. Reviewed-by:
Chaitanya Kulkarni <kch@nvidia.com> Signed-off-by:
Pavel Begunkov <asml.silence@gmail.com> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Pavel Begunkov authored
Replace bio_set_dev() with an identical inline helper and move it further to fix a dependency problem with bio_associate_blkg(). Do the same for bio_copy_dev(). Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Pavel Begunkov <asml.silence@gmail.com> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Ming Lei authored
blk_mq_quiesce_queue() has been used a bit wide now, so far we don't support concurrent/nested quiesce. One biggest issue is that unquiesce can happen unexpectedly in case that quiesce/unquiesce are run concurrently from more than one context. This patch introduces q->mq_quiesce_depth to deal concurrent quiesce, and we only unquiesce queue when it is the last/outer-most one of all contexts. Several kernel panic issue has been reported[1][2][3] when running stress quiesce test. And this patch has been verified in these reports. [1] https://lore.kernel.org/linux-block/9b21c797-e505-3821-4f5b-df7bf9380328@huawei.com/T/#m1fc52431fad7f33b1ffc3f12c4450e4238540787 [2] https://lore.kernel.org/linux-block/9b21c797-e505-3821-4f5b-df7bf9380328@huawei.com/T/#m10ad90afeb9c8cc318334190a7c24c8b5c5e0722 [3] https://listman.redhat.com/archives/dm-devel/2021-September/msg00189.html Signed-off-by:
Ming Lei <ming.lei@redhat.com> Reviewed-by:
Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211014081710.1871747-7-ming.lei@redhat.com Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Ming Lei authored
The nvme-loop's admin queue may be freed and reallocated, and we have to reset the flag of NVME_CTRL_ADMIN_Q_STOPPED so that the flag can match with the quiesce state of the admin queue. nvme-loop is the only driver to reallocate request queue, and not see such usage in other nvme drivers. Signed-off-by:
Ming Lei <ming.lei@redhat.com> Reviewed-by:
Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211014081710.1871747-6-ming.lei@redhat.com Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Ming Lei authored
The current blk_mq_quiesce_queue() and blk_mq_unquiesce_queue() always stops and starts the queue unconditionally. And there can be concurrent quiesce/unquiesce coming from different unrelated code paths, so unquiesce may come unexpectedly and start queue too early. Prepare for supporting concurrent quiesce/unquiesce from multiple contexts, so that we can address the above issue. NVMe has very complicated quiesce/unquiesce use pattern, add one atomic bit for makeiing sure that blk-mq quiece/unquiesce is always called in pair. Signed-off-by:
Ming Lei <ming.lei@redhat.com> Reviewed-by:
Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211014081710.1871747-5-ming.lei@redhat.com Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Ming Lei authored
Add two helpers so that we can prepare for pairing quiescing and unquiescing which will be done in next patch. Signed-off-by:
Ming Lei <ming.lei@redhat.com> Reviewed-by:
Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211014081710.1871747-4-ming.lei@redhat.com Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Ming Lei authored
Apply the added two APIs to quiesce/unquiesce admin queue. Signed-off-by:
Ming Lei <ming.lei@redhat.com> Reviewed-by:
Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211014081710.1871747-3-ming.lei@redhat.com Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Ming Lei authored
Add two APIs for stopping and starting admin queue. Signed-off-by:
Ming Lei <ming.lei@redhat.com> Reviewed-by:
Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211014081710.1871747-2-ming.lei@redhat.com Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Zheng Liang authored
In bfq_pd_alloc(), the function bfqg_stats_init() init bfqg. If blkg_rwstat_init() init bfqg_stats->bytes successful and init bfqg_stats->ios failed, bfqg_stats_init() return failed, bfqg will be freed. But blkg_rwstat->cpu_cnt is not deleted from the list of percpu_counters. If we traverse the list of percpu_counters, It will have UAF problem. we should use blkg_rwstat_exit() to cleanup bfqg_stats bytes in the above scenario. Fixes: commit fd41e603 ("bfq-iosched: stop using blkg->stat_bytes and ->stat_ios") Signed-off-by:
Zheng Liang <zhengliang6@huawei.com> Acked-by:
Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20211018024225.1493938-1-zhengliang6@huawei.com Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
If we don't use an IO scheduler or have shared tags, then we don't need to call into this external function at all. This saves ~2% for such a setup. Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Christoph Hellwig authored
Return to the normal blk_mq_submit_bio flow if the bio did not end up actually being a flush because the device didn't support it. Note that this is basically impossible to hit without special instrumentation given that submit_bio_checks already clears these flags usually, so we'd need a tight race to actually hit this code path. With this the call to blk_mq_run_hw_queue for the flush requests can be removed given that the actual flush requests are always issued via the requeue workqueue which runs the queue unconditionally. Signed-off-by:
Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211019122553.2467817-1-hch@lst.de Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
- Oct 19, 2021
-
-
Jens Axboe authored
If we have just one queue type in the plug list, then we can extend our direct issue to cover a full plug list as well. This allows sending a batch of requests for direct issue, which is more efficient than doing one-at-a-time kind of issue. Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
Use a singly linked list for the blk_plug. This saves 8 bytes in the blk_plug struct, and makes for faster list manipulations than doubly linked lists. As we don't use the doubly linked lists for anything, singly linked is just fine. This yields a bump in default (merging enabled) performance from 7.0 to 7.1M IOPS, and ~7.5M IOPS with merging disabled. Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Andrea Righi authored
The timer callback used to evaluate if the latency is exceeded can be executed after the corresponding disk has been released, causing the following NULL pointer dereference: [ 119.987108] BUG: kernel NULL pointer dereference, address: 0000000000000098 [ 119.987617] #PF: supervisor read access in kernel mode [ 119.987971] #PF: error_code(0x0000) - not-present page [ 119.988325] PGD 7c4a4067 P4D 7c4a4067 PUD 7bf63067 PMD 0 [ 119.988697] Oops: 0000 [#1] SMP NOPTI [ 119.988959] CPU: 1 PID: 9353 Comm: cloud-init Not tainted 5.15-rc5+arighi #rc5+arighi [ 119.989520] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 [ 119.990055] RIP: 0010:wb_timer_fn+0x44/0x3c0 [ 119.990376] Code: 41 8b 9c 24 98 00 00 00 41 8b 94 24 b8 00 00 00 41 8b 84 24 d8 00 00 00 4d 8b 74 24 28 01 d3 01 c3 49 8b 44 24 60 48 8b 40 78 <4c> 8b b8 98 00 00 00 4d 85 f6 0f 84 c4 00 00 00 49 83 7c 24 30 00 [ 119.991578] RSP: 0000:ffffb5f580957da8 EFLAGS: 0001024...
-
Jens Axboe authored
We get all sorts of unreliable and funky results since the bio is designed to align on a cacheline, which it does not when inlined like this. Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
This is in the fast path of driver issue or completion, and it's a single array index operation. Move it inline to avoid a function call for it. This does mean making struct blk_mq_tags block layer public, but there's not really much in there. Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
Even if we have multiple queues in the plug list, chances that they are very interspersed is minimal. Don't bother spending CPU cycles sorting the list. Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
Instead of returning the same queue request through a request pointer, use a boolean to accomplish the same. Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Christoph Hellwig authored
We only need to call it to resolve the blk_status_t -> errno mapping for tracing, so move the conversion into the tracepoints that are not called at all when tracing isn't enabled. Signed-off-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
This is called for every write in the fast path, move it inline next to get_disk_ro() which is called internally. Reviewed-by:
Christoph Hellwig <hch@lst.de> Reviewed-by:
Chaitanya Kulkarni <kch@nvidia.com> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
We added RQF_ELV to tell whether there's an IO scheduler attached, and RQF_ELVPRIV tells us whether there's an IO scheduler with private data attached. Don't check RQF_ELV in blk_mq_free_request(), what we care about here is just if we have scheduler private data attached. This fixes a boot crash Fixes: 2ff0682d ("block: store elevator state in request") Reported-by:
Yi Zhang <yi.zhang@redhat.com> Reported-by:
<syzbot+eb8104072aeab6cc1195@syzkaller.appspotmail.com> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
Trivial to do now, just need our own io_comp_batch on the stack and pass that in to the usual command completion handling. I pondered making this dependent on how many entries we had to process, but even for a single entry there's no discernable difference in performance or latency. Running a sync workload over io_uring: t/io_uring -b512 -d1 -s1 -c1 -p0 -F1 -B1 -n2 /dev/nvme1n1 /dev/nvme2n1 yields the below performance before the patch: IOPS=254820, BW=124MiB/s, IOS/call=1/1, inflight=(1 1) IOPS=251174, BW=122MiB/s, IOS/call=1/1, inflight=(1 1) IOPS=250806, BW=122MiB/s, IOS/call=1/1, inflight=(1 1) and the following after: IOPS=255972, BW=124MiB/s, IOS/call=1/1, inflight=(1 1) IOPS=251920, BW=123MiB/s, IOS/call=1/1, inflight=(1 1) IOPS=251794, BW=122MiB/s, IOS/call=1/1, inflight=(1 1) which definitely isn't slower, about the same if you factor in a bit of variance. For peak performance workloads, benchmarking shows a 2% improvement. Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
Wire up using an io_comp_batch for f_op->iopoll(). If the lower stack supports it, we can handle high rates of polled IO more efficiently. This raises the single core efficiency on my system from ~6.1M IOPS to ~6.6M IOPS running a random read workload at depth 128 on two gen2 Optane drives. Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
Take advantage of struct io_comp_batch, if passed in to the nvme poll handler. If it's set, rather than complete each request individually inline, store them in the io_comp_batch list. We only do so for requests that will complete successfully, anything else will be completed inline as before. Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
Instead of calling blk_mq_end_request() on a single request, add a helper that takes the new struct io_comp_batch and completes any request stored in there. Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
sbitmap currently only supports clearing tags one-by-one, add a helper that allows the caller to pass in an array of tags to clear. Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
struct io_comp_batch contains a list head and a completion handler, which will allow completions to more effciently completed batches of IO. For now, no functional changes in this patch, we just define the io_comp_batch structure and add the argument to the file_operations iopoll handler. Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
Instead of open-coding the list additions, traversal, and removal, provide a basic set of helpers. Suggested-by:
Christoph Hellwig <hch@infradead.org> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
Just like the blk_mq_ctx counterparts, we've got a bunch of counters in here that are only for debugfs and are of questionnable value. They are: - dispatched, index of how many requests were dispatched in one go - poll_{considered,invoked,success}, which track poll sucess rates. We're confident in the iopoll implementation at this point, don't bother tracking these. As a bonus, this shrinks each hardware queue from 576 bytes to 512 bytes, dropping a whole cacheline. Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
These were added as part of early days debugging for blk-mq, and they are not really useful anymore. Rather than spend cycles updating them, just get rid of them. As a bonus, this shrinks the per-cpu software queue size from 256b to 192b. That's a whole cacheline less. Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-