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2022-09-26blk-throttle: pass a gendisk to blk_throtl_cancel_biosChristoph Hellwig1-1/+2
Pass the gendisk to blk_throtl_cancel_bios as part of moving the blk-cgroup infrastructure to be gendisk based. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andreas Herrmann <aherrmann@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220921180501.1539876-15-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-26blk-throttle: pass a gendisk to blk_throtl_register_queueChristoph Hellwig1-1/+2
Pass the gendisk to blk_throtl_register_queue as part of moving the blk-cgroup infrastructure to be gendisk based. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andreas Herrmann <aherrmann@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220921180501.1539876-14-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-26blk-throttle: pass a gendisk to blk_throtl_init and blk_throtl_exitChristoph Hellwig1-2/+5
Pass the gendisk to blk_throtl_init and blk_throtl_exit as part of moving the blk-cgroup infrastructure to be gendisk based. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andreas Herrmann <aherrmann@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220921180501.1539876-13-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-24blk-throttle: improve bypassing bios checkingsYu Kuai1-4/+9
"tg->has_rules" is extended to "tg->has_rules_iops/bps", thus bios that don't need to be throttled can be checked accurately. With this patch, bio will be throttled if: 1) Bio is read/write, and corresponding read/write iops limit exist. 2) If corresponding doesn't exist, corresponding bps limit exist and bio is not throttled before. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220921095309.1481289-3-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-24blk-throttle: remove THROTL_TG_HAS_IOPS_LIMITYu Kuai1-14/+2
Currently, "tg->has_rules" and "tg->flags & THROTL_TG_HAS_IOPS_LIMIT" both try to bypass bios that don't need to be throttled, however, they are a little redundant and both not perfect: 1) "tg->has_rules" only distinguish read and write, but not iops and bps limit. 2) "tg->flags & THROTL_TG_HAS_IOPS_LIMIT" only check if iops limit exist, read and write is not distinguished, and bps limit is not checked. tg->has_rules will extended to distinguish bps and iops in the following patch. There is no need to keep the flag. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220921095309.1481289-2-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-12blk-throttle: cleanup tg_update_disptime()Yu Kuai1-4/+7
tg_update_disptime() only need to adjust postion for 'tg' in 'parent_sq', there is no need to call throtl_enqueue/dequeue_tg(), since they will set/clear flag THROTL_TG_PENDING and increase/decrease nr_pending, which is useless. By the way, clear the flag/decrease nr_pending while there are still throttled bios is not good for debugging. There are no functional changes. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220827101637.1775111-4-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-12blk-throttle: calling throtl_dequeue/enqueue_tg in pairsYu Kuai1-2/+2
It's a little weird to call throtl_dequeue_tg() unconditionally in throtl_select_dispatch(), since it will be called in tg_update_disptime() again if some bio is still throttled. Thus call it later if there are no throttled bio. There are no functional changes. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220827101637.1775111-3-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-12blk-throttle: use 'READ/WRITE' instead of '0/1'Yu Kuai1-3/+3
Make the code easier to read, like everywhere else. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220827101637.1775111-2-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-12blk-throttle: fix io hung due to configuration updatesYu Kuai1-6/+52
If new configuration is submitted while a bio is throttled, then new waiting time is recalculated regardless that the bio might already wait for some time: tg_conf_updated throtl_start_new_slice tg_update_disptime throtl_schedule_next_dispatch Then io hung can be triggered by always submmiting new configuration before the throttled bio is dispatched. Fix the problem by respecting the time that throttled bio already waited. In order to do that, add new fields to record how many bytes/io are waited, and use it to calculate wait time for throttled bio under new configuration. Some simple test: 1) cd /sys/fs/cgroup/blkio/ echo $$ > cgroup.procs echo "8:0 2048" > blkio.throttle.write_bps_device { sleep 2 echo "8:0 1024" > blkio.throttle.write_bps_device } & dd if=/dev/zero of=/dev/sda bs=8k count=1 oflag=direct 2) cd /sys/fs/cgroup/blkio/ echo $$ > cgroup.procs echo "8:0 1024" > blkio.throttle.write_bps_device { sleep 4 echo "8:0 2048" > blkio.throttle.write_bps_device } & dd if=/dev/zero of=/dev/sda bs=8k count=1 oflag=direct test results: io finish time before this patch with this patch 1) 10s 6s 2) 8s 6s Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Michal Koutný <mkoutny@suse.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220829022240.3348319-5-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-12blk-throttle: factor out code to calculate ios/bytes_allowedYu Kuai1-24/+35
No functional changes, new apis will be used in later patches to calculate wait time for throttled bios when new configuration is submitted. Noted this patch also rename tg_with_in_iops/bps_limit() to tg_within_iops/bps_limit(). Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220829022240.3348319-4-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-12blk-throttle: prevent overflow while calculating wait timeYu Kuai1-5/+3
There is a problem found by code review in tg_with_in_bps_limit() that 'bps_limit * jiffy_elapsed_rnd' might overflow. Fix the problem by calling mul_u64_u64_div_u64() instead. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220829022240.3348319-3-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-12blk-throttle: fix that io throttle can only work for single bioYu Kuai1-14/+6
Test scripts: cd /sys/fs/cgroup/blkio/ echo "8:0 1024" > blkio.throttle.write_bps_device echo $$ > cgroup.procs dd if=/dev/zero of=/dev/sda bs=10k count=1 oflag=direct & dd if=/dev/zero of=/dev/sda bs=10k count=1 oflag=direct & Test result: 10240 bytes (10 kB, 10 KiB) copied, 10.0134 s, 1.0 kB/s 10240 bytes (10 kB, 10 KiB) copied, 10.0135 s, 1.0 kB/s The problem is that the second bio is finished after 10s instead of 20s. Root cause: 1) second bio will be flagged: __blk_throtl_bio while (true) { ... if (sq->nr_queued[rw]) -> some bio is throttled already break }; bio_set_flag(bio, BIO_THROTTLED); -> flag the bio 2) flagged bio will be dispatched without waiting: throtl_dispatch_tg tg_may_dispatch tg_with_in_bps_limit if (bps_limit == U64_MAX || bio_flagged(bio, BIO_THROTTLED)) *wait = 0; -> wait time is zero return true; commit 9f5ede3c01f9 ("block: throttle split bio in case of iops limit") support to count split bios for iops limit, thus it adds flagged bio checking in tg_with_in_bps_limit() so that split bios will only count once for bps limit, however, it introduce a new problem that io throttle won't work if multiple bios are throttled. In order to fix the problem, handle iops/bps limit in different ways: 1) for iops limit, there is no flag to record if the bio is throttled, and iops is always applied. 2) for bps limit, original bio will be flagged with BIO_BPS_THROTTLED, and io throttle will ignore bio with the flag. Noted this patch also remove the code to set flag in __bio_clone(), it's introduced in commit 111be8839817 ("block-throttle: avoid double charge"), and author thinks split bio can be resubmited and throttled again, which is wrong because split bio will continue to dispatch from caller. Fixes: 9f5ede3c01f9 ("block: throttle split bio in case of iops limit") Cc: <stable@vger.kernel.org> Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220829022240.3348319-2-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-04blk-throttle: clean up codes that can't be reachedYu Kuai1-34/+56
While doing code coverage testing while CONFIG_BLK_DEV_THROTTLING_LOW is disabled, we found that there are many codes can never be reached. This patch move such codes inside "#ifdef CONFIG_BLK_DEV_THROTTLING_LOW". Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220903062826.1099085-1-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-14block: Use enum req_op where appropriateBart Van Assche1-3/+4
Change the type of the arguments that are used to pass a REQ_OP_* value from int or unsigned int into enum req_op to improve static type checking. Cc: Christoph Hellwig <hch@lst.de> Cc: Ming Lei <ming.lei@redhat.com> Cc: Hannes Reinecke <hare@suse.de> Cc: Damien Le Moal <damien.lemoal@wdc.com> Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20220714180729.1065367-3-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-17blk-throttle: Set BIO_THROTTLED when bio has been throttledLaibin Qiu1-1/+2
1.In current process, all bio will set the BIO_THROTTLED flag after __blk_throtl_bio(). 2.If bio needs to be throttled, it will start the timer and stop submit bio directly. Bio will submit in blk_throtl_dispatch_work_fn() when the timer expires.But in the current process, if bio is throttled. The BIO_THROTTLED will be set to bio after timer start. If the bio has been completed, it may cause use-after-free blow. BUG: KASAN: use-after-free in blk_throtl_bio+0x12f0/0x2c70 Read of size 2 at addr ffff88801b8902d4 by task fio/26380 dump_stack+0x9b/0xce print_address_description.constprop.6+0x3e/0x60 kasan_report.cold.9+0x22/0x3a blk_throtl_bio+0x12f0/0x2c70 submit_bio_checks+0x701/0x1550 submit_bio_noacct+0x83/0xc80 submit_bio+0xa7/0x330 mpage_readahead+0x380/0x500 read_pages+0x1c1/0xbf0 page_cache_ra_unbounded+0x471/0x6f0 do_page_cache_ra+0xda/0x110 ondemand_readahead+0x442/0xae0 page_cache_async_ra+0x210/0x300 generic_file_buffered_read+0x4d9/0x2130 generic_file_read_iter+0x315/0x490 blkdev_read_iter+0x113/0x1b0 aio_read+0x2ad/0x450 io_submit_one+0xc8e/0x1d60 __se_sys_io_submit+0x125/0x350 do_syscall_64+0x2d/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Allocated by task 26380: kasan_save_stack+0x19/0x40 __kasan_kmalloc.constprop.2+0xc1/0xd0 kmem_cache_alloc+0x146/0x440 mempool_alloc+0x125/0x2f0 bio_alloc_bioset+0x353/0x590 mpage_alloc+0x3b/0x240 do_mpage_readpage+0xddf/0x1ef0 mpage_readahead+0x264/0x500 read_pages+0x1c1/0xbf0 page_cache_ra_unbounded+0x471/0x6f0 do_page_cache_ra+0xda/0x110 ondemand_readahead+0x442/0xae0 page_cache_async_ra+0x210/0x300 generic_file_buffered_read+0x4d9/0x2130 generic_file_read_iter+0x315/0x490 blkdev_read_iter+0x113/0x1b0 aio_read+0x2ad/0x450 io_submit_one+0xc8e/0x1d60 __se_sys_io_submit+0x125/0x350 do_syscall_64+0x2d/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 0: kasan_save_stack+0x19/0x40 kasan_set_track+0x1c/0x30 kasan_set_free_info+0x1b/0x30 __kasan_slab_free+0x111/0x160 kmem_cache_free+0x94/0x460 mempool_free+0xd6/0x320 bio_free+0xe0/0x130 bio_put+0xab/0xe0 bio_endio+0x3a6/0x5d0 blk_update_request+0x590/0x1370 scsi_end_request+0x7d/0x400 scsi_io_completion+0x1aa/0xe50 scsi_softirq_done+0x11b/0x240 blk_mq_complete_request+0xd4/0x120 scsi_mq_done+0xf0/0x200 virtscsi_vq_done+0xbc/0x150 vring_interrupt+0x179/0x390 __handle_irq_event_percpu+0xf7/0x490 handle_irq_event_percpu+0x7b/0x160 handle_irq_event+0xcc/0x170 handle_edge_irq+0x215/0xb20 common_interrupt+0x60/0x120 asm_common_interrupt+0x1e/0x40 Fix this by move BIO_THROTTLED set into the queue_lock. Signed-off-by: Laibin Qiu <qiulaibin@huawei.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220301123919.2381579-1-qiulaibin@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-02blktrace: cleanup the __trace_note_message interfaceChristoph Hellwig1-1/+1
Pass the cgroup_subsys_state instead of a the blkg so that blktrace doesn't need to poke into blk-cgroup internals, and give the name a blk prefix as the current name is way too generic for a public interface. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220420042723.1010598-9-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-18block: cancel all throttled bios in del_gendisk()Yu Kuai1-1/+35
Throttled bios can't be issued after del_gendisk() is done, thus it's better to cancel them immediately rather than waiting for throttle is done. For example, if user thread is throttled with low bps while it's issuing large io, and the device is deleted. The user thread will wait for a long time for io to return. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220318130144.1066064-4-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-18block: avoid use-after-free on throttle dataMing Lei1-1/+11
In throtl_pending_timer_fn(), request queue is retrieved from throttle data. And tg's pending timer is deleted synchronously when releasing the associated blkg, at that time, throttle data may have been freed since commit 1059699f87eb ("block: move blkcg initialization/destroy into disk allocation/release handler") moves freeing q->td to disk_release() from blk_release_queue(). So use-after-free on q->td in throtl_pending_timer_fn can be triggered. Fixes the issue by: - do nothing in case that disk is released, when there isn't any bio to dispatch - retrieve request queue from blkg instead of throttle data for non top-level pending timer. Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220318130144.1066064-2-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-16block: revert 4f1e9630afe6 ("blk-throtl: optimize IOPS throttle for large IO scenarios")Ming Lei1-28/+0
Revert commit 4f1e9630afe6 ("blk-throtl: optimize IOPS throttle for large IO scenarios") since we have another easier way to address this issue and get better iops throttling result. Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220216044514.2903784-9-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-16block: don't try to throttle split bio if iops limit isn't setMing Lei1-7/+14
We need to throttle split bio in case of IOPS limit even though the split bio has been marked as BIO_THROTTLED since block layer accounts split bio actually. If only throughput throttle is setup, no need to throttle any more if BIO_THROTTLED is set since we have accounted & considered the whole bio bytes already. Add one flag of THROTL_TG_HAS_IOPS_LIMIT for serving this purpose. Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220216044514.2903784-8-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-16block: throttle split bio in case of iops limitMing Lei1-3/+7
Commit 111be8839817 ("block-throttle: avoid double charge") marks bio as BIO_THROTTLED unconditionally if __blk_throtl_bio() is called on this bio, then this bio won't be called into __blk_throtl_bio() any more. This way is to avoid double charge in case of bio splitting. It is reasonable for read/write throughput limit, but not reasonable for IOPS limit because block layer provides io accounting against split bio. Chunguang Xu has already observed this issue and fixed it in commit 4f1e9630afe6 ("blk-throtl: optimize IOPS throttle for large IO scenarios"). However, that patch only covers bio splitting in __blk_queue_split(), and we have other kind of bio splitting, such as bio_split() & submit_bio_noacct() and other ways. This patch tries to fix the issue in one generic way by always charging the bio for iops limit in blk_throtl_bio(). This way is reasonable: re-submission & fast-cloned bio is charged if it is submitted to same disk/queue, and BIO_THROTTLED will be cleared if bio->bi_bdev is changed. This new approach can get much more smooth/stable iops limit compared with commit 4f1e9630afe6 ("blk-throtl: optimize IOPS throttle for large IO scenarios") since that commit can't throttle current split bios actually. Also this way won't cause new double bio iops charge in blk_throtl_dispatch_work_fn() in which blk_throtl_bio() won't be called any more. Reported-by: Ning Li <lining2020x@163.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: Chunguang Xu <brookxu@tencent.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220216044514.2903784-7-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-16block: don't check bio in blk_throtl_dispatch_work_fnMing Lei1-1/+1
The bio has been checked already before throttling, so no need to check it again before dispatching it from throttle queue. Add a helper of submit_bio_noacct_nocheck() for this purpose. Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220216044514.2903784-5-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-11block: partition include/linux/blk-cgroup.hMing Lei1-1/+0
Partition include/linux/blk-cgroup.h into two parts: one is public part, the other is block layer private part. Suggested by Christoph Hellwig. Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220211101149.2368042-4-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29block: don't include blk-mq.h in blk.hChristoph Hellwig1-0/+1
No needed, shift a blk-stat.h include into the source file that needs it instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211123185312.1432157-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18block: convert the rest of block to bdev_get_queuePavel Begunkov1-1/+1
Convert bdev->bd_disk->queue to bdev_get_queue(), it's uses a cached queue pointer and so is faster. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/addf6ea988c04213697ba3684c853e4ed7642a39.1634219547.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18block: move blk-throtl fast path inlineJens Axboe1-158/+3
Even if no policies are defined, we spend ~2% of the total IO time checking. Move the fast path inline. Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-09-07blk-throttle: fix UAF by deleteing timer in blk_throtl_exit()Li Jinlin1-0/+1
The pending timer has been set up in blk_throtl_init(). However, the timer is not deleted in blk_throtl_exit(). This means that the timer handler may still be running after freeing the timer, which would result in a use-after-free. Fix by calling del_timer_sync() to delete the timer in blk_throtl_exit(). Signed-off-by: Li Jinlin <lijinlin3@huawei.com> Link: https://lore.kernel.org/r/20210907121242.2885564-1-lijinlin3@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-14blk-throtl: optimize IOPS throttle for large IO scenariosChunguang Xu1-0/+32
After patch 54efd50 (block: make generic_make_request handle arbitrarily sized bios), the IO through io-throttle may be larger, and these IOs may be further split into more small IOs. However, IOPS throttle does not seem to be aware of this change, which makes the calculation of IOPS of large IOs incomplete, resulting in disk-side IOPS that does not meet expectations. Maybe we should fix this problem. We can reproduce it by set max_sectors_kb of disk to 128, set blkio.write_iops_throttle to 100, run a dd instance inside blkio and use iostat to watch IOPS: dd if=/dev/zero of=/dev/sdb bs=1M count=1000 oflag=direct As a result, without this change the average IOPS is 1995, with this change the IOPS is 98. Signed-off-by: Chunguang Xu <brookxu@tencent.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/65869aaad05475797d63b4c3fed4f529febe3c26.1627876014.git.brookxu@tencent.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-24block: store a block_device pointer in struct bioChristoph Hellwig1-1/+1
Replace the gendisk pointer in struct bio with a pointer to the newly improved struct block device. From that the gendisk can be trivially accessed with an extra indirection, but it also allows to directly look up all information related to partition remapping. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-02blk-throttle: don't check whether or not lower limit is valid if CONFIG_BLK_DEV_THROTTLING_LOW is offYu Kuai1-0/+6
blk_throtl_update_limit_valid() will search for descendants to see if 'LIMIT_LOW' of bps/iops and READ/WRITE is nonzero. However, they're always zero if CONFIG_BLK_DEV_THROTTLING_LOW is not set, furthermore, a lot of time will be wasted to iterate descendants. Thus do nothing in blk_throtl_update_limit_valid() in such situation. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-08blk-throttle: Re-use the throtl_set_slice_end()Baolin Wang1-1/+1
Re-use throtl_set_slice_end() to remove duplicate code. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-08blk-throttle: Open code __throtl_de/enqueue_tg()Baolin Wang1-17/+9
The __throtl_de/enqueue_tg() functions are only be called by throtl_de/enqueue_tg(), thus we can just open code them to make code more readable. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-08blk-throttle: Move service tree validation out of the throtl_rb_first()Baolin Wang1-4/+5
The throtl_schedule_next_dispatch() will validate if the service queue is empty before calling update_min_dispatch_time(), and the update_min_dispatch_time() will call throtl_rb_first(), which will validate service queue again. Thus we can move the service queue validation out of the throtl_rb_first() to remove the redundant validation in the fast path. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-08blk-throttle: Move the list operation after list validationBaolin Wang1-2/+4
We should move the list operation after validation. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-08blk-throttle: Fix IO hang for a corner caseBaolin Wang1-4/+4
It can not scale up in throtl_adjusted_limit() if we set bps or iops is 1, which will cause IO hang when enable low limit. Thus we should treat 1 as a illegal value to avoid this issue. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-08blk-throttle: Avoid tracking latency if low limit is invalidBaolin Wang1-1/+3
The IO latency tracking is only for LOW limit, so we should add a validation to avoid redundant latency tracking if the LOW limit is not valid. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-08blk-throttle: Avoid getting the current time if tg->last_finish_time is 0Baolin Wang1-2/+6
We only update the tg->last_finish_time when the low limitaion is enabled, so we can move the tg->last_finish_time validation a little forward to avoid getting the unnecessary current time stamp if the the low limitation is not enabled. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-08blk-throttle: Remove a meaningless parameter for throtl_downgrade_state()Baolin Wang1-3/+3
The throtl_downgrade_state() is always used to change to LIMIT_LOW limitation, thus remove the latter meaningless parameter which indicates the limitation index. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-14blk-throttle: Avoid checking bps/iops limitation if bps or iops is unlimitedBaolin Wang1-0/+12
Do not need check the bps or iops limitation if bps or iops is unlimited. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-14blk-throttle: Avoid calculating bps/iops limitation repeatedlyBaolin Wang1-9/+10
The tg_may_dispatch() will call tg_with_in_bps_limit() and tg_with_in_iops_limit() to check if we can dispatch a bio or not, which will calculate bps/iops limitation multiple times. But tg_may_dispatch() is always called under queue lock, which means the bps/iops limitation will not change in tg_may_dispatch(). So we can calculate the bps/iops limitation only once, and pass them to tg_with_in_bps_limit() and tg_with_in_iops_limit() to avoid calculating bps/iops limitation repeatedly. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-14blk-throttle: Define readable macros instead of static variablesBaolin Wang1-5/+5
The 'throtl_grp_quantum' and 'throtl_quantum' are both read-only variables, thus better to use readable macros instead of static variables, which can also save some spaces for .bss area. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-14blk-throttle: Use readable READ/WRITE macrosBaolin Wang1-2/+2
Use readable READ/WRITE macros instead of magic numbers. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-14blk-throttle: Fix some comments' typosBaolin Wang1-7/+7
Fix some comments' typos. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01block: rename generic_make_request to submit_bio_noacctChristoph Hellwig1-2/+2
generic_make_request has always been very confusingly misnamed, so rename it to submit_bio_noacct to make it clear that it is submit_bio minus accounting and a few checks. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-29blk-cgroup: remove a dead check in blk_throtl_bioChristoph Hellwig1-1/+1
bios must have a valid block group by the time they are submitted. Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-29blk-cgroup: remove blkcg_bio_issue_checkChristoph Hellwig1-2/+3
blkcg_bio_issue_check is a giant inline function that does three entirely different things. Factor out the blk-cgroup related bio initalization into a new helper, and the open code the sequence in the only caller, relying on the fact that all the actual functionality is stubbed out for non-cgroup builds. Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-29blk-cgroup: move rcu locking from blkcg_bio_issue_check to blk_throtl_bioChristoph Hellwig1-1/+2
The only thing in blkcg_bio_issue_check that needs to be under rcu_read_lock is blk_throtl_bio, so move the locking there. Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-29blk-throttle: remove tg_drain_biosGuoqing Jiang1-22/+0
After blk_throtl_drain is removed, there is no caller of tg_drain_bios, so remove it as well. Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-29blk-throttle: remove blk_throtl_drainGuoqing Jiang1-41/+0
After the commit 5addeae1bedc4 ("blk-cgroup: remove blkcg_drain_queue"), there is no caller of blk_throtl_drain, so let's remove it. Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-07blk-cgroup: separate out blkg_rwstat under CONFIG_BLK_CGROUP_RWSTATTejun Heo1-0/+1
blkg_rwstat is now only used by bfq-iosched and blk-throtl when on cgroup1. Let's move it into its own files and gate it behind a config option. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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