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2022-08-31blk-mq: fix io hung due to missing commit_rqsYu Kuai1-2/+3
commit 65fac0d54f374625b43a9d6ad1f2c212bd41f518 upstream. Currently, in virtio_scsi, if 'bd->last' is not set to true while dispatching request, such io will stay in driver's queue, and driver will wait for block layer to dispatch more rqs. However, if block layer failed to dispatch more rq, it should trigger commit_rqs to inform driver. There is a problem in blk_mq_try_issue_list_directly() that commit_rqs won't be called: // assume that queue_depth is set to 1, list contains two rq blk_mq_try_issue_list_directly blk_mq_request_issue_directly // dispatch first rq // last is false __blk_mq_try_issue_directly blk_mq_get_dispatch_budget // succeed to get first budget __blk_mq_issue_directly scsi_queue_rq cmd->flags |= SCMD_LAST virtscsi_queuecommand kick = (sc->flags & SCMD_LAST) != 0 // kick is false, first rq won't issue to disk queued++ blk_mq_request_issue_directly // dispatch second rq __blk_mq_try_issue_directly blk_mq_get_dispatch_budget // failed to get second budget ret == BLK_STS_RESOURCE blk_mq_request_bypass_insert // errors is still 0 if (!list_empty(list) || errors && ...) // won't pass, commit_rqs won't be called In this situation, first rq relied on second rq to dispatch, while second rq relied on first rq to complete, thus they will both hung. Fix the problem by also treat 'BLK_STS_*RESOURCE' as 'errors' since it means that request is not queued successfully. Same problem exists in blk_mq_dispatch_rq_list(), 'BLK_STS_*RESOURCE' can't be treated as 'errors' here, fix the problem by calling commit_rqs if queue_rq return 'BLK_STS_*RESOURCE'. Fixes: d666ba98f849 ("blk-mq: add mq_ops->commit_rqs()") Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220726122224.1790882-1-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-22block: Fix handling of offline queues in blk_mq_alloc_request_hctx()Bart Van Assche1-0/+2
[ Upstream commit 14dc7a18abbe4176f5626c13c333670da8e06aa1 ] This patch prevents that test nvme/004 triggers the following: UBSAN: array-index-out-of-bounds in block/blk-mq.h:135:9 index 512 is out of range for type 'long unsigned int [512]' Call Trace: show_stack+0x52/0x58 dump_stack_lvl+0x49/0x5e dump_stack+0x10/0x12 ubsan_epilogue+0x9/0x3b __ubsan_handle_out_of_bounds.cold+0x44/0x49 blk_mq_alloc_request_hctx+0x304/0x310 __nvme_submit_sync_cmd+0x70/0x200 [nvme_core] nvmf_connect_io_queue+0x23e/0x2a0 [nvme_fabrics] nvme_loop_connect_io_queues+0x8d/0xb0 [nvme_loop] nvme_loop_create_ctrl+0x58e/0x7d0 [nvme_loop] nvmf_create_ctrl+0x1d7/0x4d0 [nvme_fabrics] nvmf_dev_write+0xae/0x111 [nvme_fabrics] vfs_write+0x144/0x560 ksys_write+0xb7/0x140 __x64_sys_write+0x42/0x50 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae Cc: Christoph Hellwig <hch@lst.de> Cc: Ming Lei <ming.lei@redhat.com> Fixes: 20e4d8139319 ("blk-mq: simplify queue mapping & schedule with each possisble CPU") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220615210004.1031820-1-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14blk-mq: don't touch ->tagset in blk_mq_get_sq_hctxMing Lei1-4/+3
[ Upstream commit 5d05426e2d5fd7df8afc866b78c36b37b00188b7 ] blk_mq_run_hw_queues() could be run when there isn't queued request and after queue is cleaned up, at that time tagset is freed, because tagset lifetime is covered by driver, and often freed after blk_cleanup_queue() returns. So don't touch ->tagset for figuring out current default hctx by the mapping built in request queue, so use-after-free on tagset can be avoided. Meantime this way should be fast than retrieving mapping from tagset. Cc: "yukuai (C)" <yukuai3@huawei.com> Cc: Jan Kara <jack@suse.cz> Fixes: b6e68ee82585 ("blk-mq: Improve performance of non-mq IO schedulers with multiple HW queues") Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20220522122350.743103-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-12-01blk-mq: cancel blk-mq dispatch work in both blk_cleanup_queue and disk_release()Ming Lei1-0/+13
commit 2a19b28f7929866e1cec92a3619f4de9f2d20005 upstream. For avoiding to slow down queue destroy, we don't call blk_mq_quiesce_queue() in blk_cleanup_queue(), instead of delaying to cancel dispatch work in blk_release_queue(). However, this way has caused kernel oops[1], reported by Changhui. The log shows that scsi_device can be freed before running blk_release_queue(), which is expected too since scsi_device is released after the scsi disk is closed and the scsi_device is removed. Fixes the issue by canceling blk-mq dispatch work in both blk_cleanup_queue() and disk_release(): 1) when disk_release() is run, the disk has been closed, and any sync dispatch activities have been done, so canceling dispatch work is enough to quiesce filesystem I/O dispatch activity. 2) in blk_cleanup_queue(), we only focus on passthrough request, and passthrough request is always explicitly allocated & freed by its caller, so once queue is frozen, all sync dispatch activity for passthrough request has been done, then it is enough to just cancel dispatch work for avoiding any dispatch activity. [1] kernel panic log [12622.769416] BUG: kernel NULL pointer dereference, address: 0000000000000300 [12622.777186] #PF: supervisor read access in kernel mode [12622.782918] #PF: error_code(0x0000) - not-present page [12622.788649] PGD 0 P4D 0 [12622.791474] Oops: 0000 [#1] PREEMPT SMP PTI [12622.796138] CPU: 10 PID: 744 Comm: kworker/10:1H Kdump: loaded Not tainted 5.15.0+ #1 [12622.804877] Hardware name: Dell Inc. PowerEdge R730/0H21J3, BIOS 1.5.4 10/002/2015 [12622.813321] Workqueue: kblockd blk_mq_run_work_fn [12622.818572] RIP: 0010:sbitmap_get+0x75/0x190 [12622.823336] Code: 85 80 00 00 00 41 8b 57 08 85 d2 0f 84 b1 00 00 00 45 31 e4 48 63 cd 48 8d 1c 49 48 c1 e3 06 49 03 5f 10 4c 8d 6b 40 83 f0 01 <48> 8b 33 44 89 f2 4c 89 ef 0f b6 c8 e8 fa f3 ff ff 83 f8 ff 75 58 [12622.844290] RSP: 0018:ffffb00a446dbd40 EFLAGS: 00010202 [12622.850120] RAX: 0000000000000001 RBX: 0000000000000300 RCX: 0000000000000004 [12622.858082] RDX: 0000000000000006 RSI: 0000000000000082 RDI: ffffa0b7a2dfe030 [12622.866042] RBP: 0000000000000004 R08: 0000000000000001 R09: ffffa0b742721334 [12622.874003] R10: 0000000000000008 R11: 0000000000000008 R12: 0000000000000000 [12622.881964] R13: 0000000000000340 R14: 0000000000000000 R15: ffffa0b7a2dfe030 [12622.889926] FS: 0000000000000000(0000) GS:ffffa0baafb40000(0000) knlGS:0000000000000000 [12622.898956] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [12622.905367] CR2: 0000000000000300 CR3: 0000000641210001 CR4: 00000000001706e0 [12622.913328] Call Trace: [12622.916055] <TASK> [12622.918394] scsi_mq_get_budget+0x1a/0x110 [12622.922969] __blk_mq_do_dispatch_sched+0x1d4/0x320 [12622.928404] ? pick_next_task_fair+0x39/0x390 [12622.933268] __blk_mq_sched_dispatch_requests+0xf4/0x140 [12622.939194] blk_mq_sched_dispatch_requests+0x30/0x60 [12622.944829] __blk_mq_run_hw_queue+0x30/0xa0 [12622.949593] process_one_work+0x1e8/0x3c0 [12622.954059] worker_thread+0x50/0x3b0 [12622.958144] ? rescuer_thread+0x370/0x370 [12622.962616] kthread+0x158/0x180 [12622.966218] ? set_kthread_struct+0x40/0x40 [12622.970884] ret_from_fork+0x22/0x30 [12622.974875] </TASK> [12622.977309] Modules linked in: scsi_debug rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs sunrpc dm_multipath intel_rapl_msr intel_rapl_common dell_wmi_descriptor sb_edac rfkill video x86_pkg_temp_thermal intel_powerclamp dcdbas coretemp kvm_intel kvm mgag200 irqbypass i2c_algo_bit rapl drm_kms_helper ipmi_ssif intel_cstate intel_uncore syscopyarea sysfillrect sysimgblt fb_sys_fops pcspkr cec mei_me lpc_ich mei ipmi_si ipmi_devintf ipmi_msghandler acpi_power_meter drm fuse xfs libcrc32c sr_mod cdrom sd_mod t10_pi sg ixgbe ahci libahci crct10dif_pclmul crc32_pclmul crc32c_intel libata megaraid_sas ghash_clmulni_intel tg3 wdat_wdt mdio dca wmi dm_mirror dm_region_hash dm_log dm_mod [last unloaded: scsi_debug] Reported-by: ChanghuiZhong <czhong@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Bart Van Assche <bvanassche@acm.org> Cc: linux-scsi@vger.kernel.org Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20211116014343.610501-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-18block: remove inaccurate requeue checkJens Axboe1-1/+0
[ Upstream commit 037057a5a979c7eeb2ee5d12cf4c24b805192c75 ] 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> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-18block: bump max plugged deferred size from 16 to 32Jens Axboe1-2/+2
[ Upstream commit ba0ffdd8ce48ad7f7e85191cd29f9674caca3745 ] Particularly for NVMe with efficient deferred submission for many requests, there are nice benefits to be seen by bumping the default max plug count from 16 to 32. This is especially true for virtualized setups, where the submit part is more expensive. But can be noticed even on native hardware. Reduce the multiple queue factor from 4 to 2, since we're changing the default size. While changing it, move the defines into the block layer private header. These aren't values that anyone outside of the block layer uses, or should use. Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-10-27block: schedule queue restart after BLK_STS_ZONE_RESOURCENaohiro Aota1-4/+9
When dispatching a zone append write request to a SCSI zoned block device, if the target zone of the request is already locked, the device driver will return BLK_STS_ZONE_RESOURCE and the request will be pushed back to the hctx dipatch queue. The queue will be marked as RESTART in dd_finish_request() and restarted in __blk_mq_free_request(). However, this restart applies to the hctx of the completed request. If the requeued request is on a different hctx, dispatch will no be retried until another request is submitted or the next periodic queue run triggers, leading to up to 30 seconds latency for the requeued request. Fix this problem by scheduling a queue restart similarly to the BLK_STS_RESOURCE case or when we cannot get the budget. Also, consolidate the checks into the "need_resource" variable to simplify the condition. Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Niklas Cassel <Niklas.Cassel@wdc.com> Link: https://lore.kernel.org/r/20211026165127.4151055-1-naohiro.aota@wdc.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-16block: keep q_usage_counter in atomic mode after del_gendiskChristoph Hellwig1-1/+8
Don't switch back to percpu mode to avoid the double RCU grace period when tearing down SCSI devices. After removing the disk only passthrough commands can be send anyway. Suggested-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Darrick J. Wong <djwong@kernel.org> Link: https://lore.kernel.org/r/20210929071241.934472-6-hch@lst.de Tested-by: Yi Zhang <yi.zhang@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-09-11Merge tag 'block-5.15-2021-09-11' of git://git.kernel.dk/linux-blockLinus Torvalds1-1/+13
Pull block fixes from Jens Axboe: - NVMe pull request from Christoph: - fix nvmet command set reporting for passthrough controllers (Adam Manzanares) - update a MAINTAINERS email address (Chaitanya Kulkarni) - set QUEUE_FLAG_NOWAIT for nvme-multipth (me) - handle errors from add_disk() (Luis Chamberlain) - update the keep alive interval when kato is modified (Tatsuya Sasaki) - fix a buffer overrun in nvmet_subsys_attr_serial (Hannes Reinecke) - do not reset transport on data digest errors in nvme-tcp (Daniel Wagner) - only call synchronize_srcu when clearing current path (Daniel Wagner) - revalidate paths during rescan (Hannes Reinecke) - Split out the fs/block_dev into block/fops.c and block/bdev.c, which has been long overdue. Do this now before -rc1, to avoid annoying conflicts due to this (Christoph) - blk-throtl use-after-free fix (Li) - Improve plug depth for multi-device plugs, greatly increasing md resync performance (Song) - blkdev_show() locking fix (Tetsuo) - n64cart error check fix (Yang) * tag 'block-5.15-2021-09-11' of git://git.kernel.dk/linux-block: n64cart: fix return value check in n64cart_probe() blk-mq: allow 4x BLK_MAX_REQUEST_COUNT at blk_plug for multiple_queues block: move fs/block_dev.c to block/bdev.c block: split out operations on block special files blk-throttle: fix UAF by deleteing timer in blk_throtl_exit() block: genhd: don't call blkdev_show() with major_names_lock held nvme: update MAINTAINERS email address nvme: add error handling support for add_disk() nvme: only call synchronize_srcu when clearing current path nvme: update keep alive interval when kato is modified nvme-tcp: Do not reset transport on data digest errors nvmet: fixup buffer overrun in nvmet_subsys_attr_serial() nvmet: return bool from nvmet_passthru_ctrl and nvmet_is_passthru_req nvmet: looks at the passthrough controller when initializing CAP nvme: move nvme_multi_css into nvme.h nvme-multipath: revalidate paths during rescan nvme-multipath: set QUEUE_FLAG_NOWAIT
2021-09-08blk-mq: allow 4x BLK_MAX_REQUEST_COUNT at blk_plug for multiple_queuesSong Liu1-1/+13
Limiting number of request to BLK_MAX_REQUEST_COUNT at blk_plug hurts performance for large md arrays. [1] shows resync speed of md array drops for md array with more than 16 HDDs. Fix this by allowing more request at plug queue. The multiple_queue flag is used to only apply higher limit to multiple queue cases. [1] https://lore.kernel.org/linux-raid/CAFDAVznS71BXW8Jxv6k9dXc2iR3ysX3iZRBww_rzA8WifBFxGg@mail.gmail.com/ Tested-by: Marcin Wanat <marcin.wanat@gmail.com> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-09-03Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds1-2/+0
Pull SCSI updates from James Bottomley: "This series consists of the usual driver updates (ufs, qla2xxx, target, smartpqi, lpfc, mpt3sas). The core change causing the most churn was replacing the command request field request with a macro, allowing us to offset map to it and remove the redundant field; the same was also done for the tag field. The most impactful change is the final removal of scsi_ioctl, which has been deprecated for over a decade" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (293 commits) scsi: ufs: Fix ufshcd_request_sense_async() for Samsung KLUFG8RHDA-B2D1 scsi: ufs: ufs-exynos: Fix static checker warning scsi: mpt3sas: Use the proper SCSI midlayer interfaces for PI scsi: lpfc: Use the proper SCSI midlayer interfaces for PI scsi: lpfc: Copyright updates for 14.0.0.1 patches scsi: lpfc: Update lpfc version to 14.0.0.1 scsi: lpfc: Add bsg support for retrieving adapter cmf data scsi: lpfc: Add cmf_info sysfs entry scsi: lpfc: Add debugfs support for cm framework buffers scsi: lpfc: Add support for maintaining the cm statistics buffer scsi: lpfc: Add rx monitoring statistics scsi: lpfc: Add support for the CM framework scsi: lpfc: Add cmfsync WQE support scsi: lpfc: Add support for cm enablement buffer scsi: lpfc: Add cm statistics buffer support scsi: lpfc: Add EDC ELS support scsi: lpfc: Expand FPIN and RDF receive logging scsi: lpfc: Add MIB feature enablement support scsi: lpfc: Add SET_HOST_DATA mbox cmd to pass date/time info to firmware scsi: fc: Add EDC ELS definition ...
2021-08-31Merge tag 'for-5.15/block-2021-08-30' of git://git.kernel.dk/linux-blockLinus Torvalds1-4/+4
Pull block updates from Jens Axboe: "Nothing major in here - lots of good cleanups and tech debt handling, which is also evident in the diffstats. In particular: - Add disk sequence numbers (Matteo) - Discard merge fix (Ming) - Relax disk zoned reporting restrictions (Niklas) - Bio error handling zoned leak fix (Pavel) - Start of proper add_disk() error handling (Luis, Christoph) - blk crypto fix (Eric) - Non-standard GPT location support (Dmitry) - IO priority improvements and cleanups (Damien)o - blk-throtl improvements (Chunguang) - diskstats_show() stack reduction (Abd-Alrhman) - Loop scheduler selection (Bart) - Switch block layer to use kmap_local_page() (Christoph) - Remove obsolete disk_name helper (Christoph) - block_device refcounting improvements (Christoph) - Ensure gendisk always has a request queue reference (Christoph) - Misc fixes/cleanups (Shaokun, Oliver, Guoqing)" * tag 'for-5.15/block-2021-08-30' of git://git.kernel.dk/linux-block: (129 commits) sg: pass the device name to blk_trace_setup block, bfq: cleanup the repeated declaration blk-crypto: fix check for too-large dun_bytes blk-zoned: allow BLKREPORTZONE without CAP_SYS_ADMIN blk-zoned: allow zone management send operations without CAP_SYS_ADMIN block: mark blkdev_fsync static block: refine the disk_live check in del_gendisk mmc: sdhci-tegra: Enable MMC_CAP2_ALT_GPT_TEGRA mmc: block: Support alternative_gpt_sector() operation partitions/efi: Support non-standard GPT location block: Add alternative_gpt_sector() operation bio: fix page leak bio_add_hw_page failure block: remove CONFIG_DEBUG_BLOCK_EXT_DEVT block: remove a pointless call to MINOR() in device_add_disk null_blk: add error handling support for add_disk() virtio_blk: add error handling support for add_disk() block: add error handling for device_add_disk / add_disk block: return errors from disk_alloc_events block: return errors from blk_integrity_add block: call blk_register_queue earlier in device_add_disk ...
2021-08-31Merge tag 'irq-core-2021-08-30' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "Updates to the interrupt core and driver subsystems: Core changes: - The usual set of small fixes and improvements all over the place, but nothing stands out MSI changes: - Further consolidation of the PCI/MSI interrupt chip code - Make MSI sysfs code independent of PCI/MSI and expose the MSI interrupts of platform devices in the same way as PCI exposes them. Driver changes: - Support for ARM GICv3 EPPI partitions - Treewide conversion to generic_handle_domain_irq() for all chained interrupt controllers - Conversion to bitmap_zalloc() throughout the irq chip drivers - The usual set of small fixes and improvements" * tag 'irq-core-2021-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits) platform-msi: Add ABI to show msi_irqs of platform devices genirq/msi: Move MSI sysfs handling from PCI to MSI core genirq/cpuhotplug: Demote debug printk to KERN_DEBUG irqchip/qcom-pdc: Trim unused levels of the interrupt hierarchy irqdomain: Export irq_domain_disconnect_hierarchy() irqchip/gic-v3: Fix priority comparison when non-secure priorities are used irqchip/apple-aic: Fix irq_disable from within irq handlers pinctrl/rockchip: drop the gpio related codes gpio/rockchip: drop irq_gc_lock/irq_gc_unlock for irq set type gpio/rockchip: support next version gpio controller gpio/rockchip: use struct rockchip_gpio_regs for gpio controller gpio/rockchip: add driver for rockchip gpio dt-bindings: gpio: change items restriction of clock for rockchip,gpio-bank pinctrl/rockchip: add pinctrl device to gpio bank struct pinctrl/rockchip: separate struct rockchip_pin_bank to a head file pinctrl/rockchip: always enable clock for gpio controller genirq: Fix kernel doc indentation EDAC/altera: Convert to generic_handle_domain_irq() powerpc: Bulk conversion to generic_handle_domain_irq() nios2: Bulk conversion to generic_handle_domain_irq() ...
2021-08-23block: add an explicit ->disk backpointer to the request_queueChristoph Hellwig1-1/+1
Replace the magic lookup through the kobject tree with an explicit backpointer, given that the device model links are set up and torn down at times when I/O is still possible, leading to potential NULL or invalid pointer dereferences. Fixes: edb0872f44ec ("block: move the bdi from the request_queue to the gendisk") Reported-by: syzbot <syzbot+aa0801b6b32dca9dda82@syzkaller.appspotmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Sven Schnelle <svens@linux.ibm.com> Link: https://lore.kernel.org/r/20210816134624.GA24234@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-23block: pass a request_queue to __blk_alloc_diskChristoph Hellwig1-2/+1
Pass in a request_queue and assign disk->queue in __blk_alloc_disk to ensure struct gendisk always has a valid ->queue pointer. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210816131910.615153-8-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-23block: remove the minors argument to __alloc_disk_nodeChristoph Hellwig1-1/+1
This was a leftover from the legacy alloc_disk interface. Switch the scsi ULPs and dasd to set ->minors directly like all other drivers and remove the argument. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Stefan Haberland <sth@linux.ibm.com> [dasd] Link: https://lore.kernel.org/r/20210816131910.615153-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-23block: cleanup the lockdep handling in *alloc_diskChristoph Hellwig1-2/+3
Pass the lockdep name to the low-level __blk_alloc_disk helper and hardcode the name for it given that the number of minors or node_id are not very useful information. While this passes a pointless argument for non-lockdep builds that is not really an issue as disk allocation is a probe time only slow path. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210816131910.615153-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-18blk-mq: fix is_flush_rqMing Lei1-1/+1
is_flush_rq() is called from bt_iter()/bt_tags_iter(), and runs the following check: hctx->fq->flush_rq == req but the passed hctx from bt_iter()/bt_tags_iter() may be NULL because: 1) memory re-order in blk_mq_rq_ctx_init(): rq->mq_hctx = data->hctx; ... refcount_set(&rq->ref, 1); OR 2) tag re-use and ->rqs[] isn't updated with new request. Fix the issue by re-writing is_flush_rq() as: return rq->end_io == flush_end_io; which turns out simpler to follow and immune to data race since we have ordered WRITE rq->end_io and refcount_set(&rq->ref, 1). Fixes: 2e315dc07df0 ("blk-mq: grab rq->refcount before calling ->fn in blk_mq_tagset_busy_iter") Cc: "Blank-Burian, Markus, Dr." <blankburian@uni-muenster.de> Cc: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210818010925.607383-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-17blk-mq: don't grab rq's refcount in blk_mq_check_expired()Ming Lei1-25/+5
Inside blk_mq_queue_tag_busy_iter() we already grabbed request's refcount before calling ->fn(), so needn't to grab it one more time in blk_mq_check_expired(). Meantime remove extra request expire check in blk_mq_check_expired(). Cc: Keith Busch <kbusch@kernel.org> Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: John Garry <john.garry@huawei.com> Link: https://lore.kernel.org/r/20210811155202.629575-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-13blk-mq: clear active_queues before clearing BLK_MQ_F_TAG_QUEUE_SHAREDYu Kuai1-2/+4
We run a test that delete and recover devcies frequently(two devices on the same host), and we found that 'active_queues' is super big after a period of time. If device a and device b share a tag set, and a is deleted, then blk_mq_exit_queue() will clear BLK_MQ_F_TAG_QUEUE_SHARED because there is only one queue that are using the tag set. However, if b is still active, the active_queues of b might never be cleared even if b is deleted. Thus clear active_queues before BLK_MQ_F_TAG_QUEUE_SHARED is cleared. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210731062130.1533893-1-yukuai3@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-10genirq: Change force_irqthreads to a static keyTanner Love1-1/+1
With CONFIG_IRQ_FORCED_THREADING=y, testing the boolean force_irqthreads could incur a cache line miss in invoke_softirq() and other places. Replace the test with a static key to avoid the potential cache miss. [ tglx: Dropped the IDE part, removed the export and updated blk-mq ] Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Tanner Love <tannerlove@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210602180338.3324213-1-tannerlove.kernel@gmail.com
2021-08-09block: move the bdi from the request_queue to the gendiskChristoph Hellwig1-1/+1
The backing device information only makes sense for file system I/O, and thus belongs into the gendisk and not the lower level request_queue structure. Move it there. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20210809141744.1203023-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-31scsi: block: Remove the remaining SG_IO-related fields from struct request_queueChristoph Hellwig1-2/+0
Move the sg_timeout and sg_reserved_size fields into the bsg_device and scsi_device structures as they have nothing to do with generic block I/O. Note that these values are now separate for bsg vs. SCSI device node access, but that just matches how /dev/sg vs the other nodes has always behaved. Link: https://lore.kernel.org/r/20210729064845.1044147-4-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-07-01block: mark blk_mq_init_queue_data staticChristoph Hellwig1-2/+1
All driver uses are gone now. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20210624081012.256464-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-30Merge tag 'for-5.14/block-2021-06-29' of git://git.kernel.dk/linux-blockLinus Torvalds1-67/+139
Pull core block updates from Jens Axboe: - disk events cleanup (Christoph) - gendisk and request queue allocation simplifications (Christoph) - bdev_disk_changed cleanups (Christoph) - IO priority improvements (Bart) - Chained bio completion trace fix (Edward) - blk-wbt fixes (Jan) - blk-wbt enable/disable fix (Zhang) - Scheduler dispatch improvements (Jan, Ming) - Shared tagset scheduler improvements (John) - BFQ updates (Paolo, Luca, Pietro) - BFQ lock inversion fix (Jan) - Documentation improvements (Kir) - CLONE_IO block cgroup fix (Tejun) - Remove of ancient and deprecated block dump feature (zhangyi) - Discard merge fix (Ming) - Misc fixes or followup fixes (Colin, Damien, Dan, Long, Max, Thomas, Yang) * tag 'for-5.14/block-2021-06-29' of git://git.kernel.dk/linux-block: (129 commits) block: fix discard request merge block/mq-deadline: Remove a WARN_ON_ONCE() call blk-mq: update hctx->dispatch_busy in case of real scheduler blk: Fix lock inversion between ioc lock and bfqd lock bfq: Remove merged request already in bfq_requests_merged() block: pass a gendisk to bdev_disk_changed block: move bdev_disk_changed block: add the events* attributes to disk_attrs block: move the disk events code to a separate file block: fix trace completion for chained bio block/partitions/msdos: Fix typo inidicator -> indicator block, bfq: reset waker pointer with shared queues block, bfq: check waker only for queues with no in-flight I/O block, bfq: avoid delayed merge of async queues block, bfq: boost throughput by extending queue-merging times block, bfq: consider also creation time in delayed stable merge block, bfq: fix delayed stable merge check block, bfq: let also stably merged queues enjoy weight raising blk-wbt: make sure throttle is enabled properly blk-wbt: introduce a new disable state to prevent false positive by rwb_enabled() ...
2021-06-25blk-mq: update hctx->dispatch_busy in case of real schedulerMing Lei1-3/+0
Commit 6e6fcbc27e77 ("blk-mq: support batching dispatch in case of io") starts to support io batching submission by using hctx->dispatch_busy. However, blk_mq_update_dispatch_busy() isn't changed to update hctx->dispatch_busy in that commit, so fix the issue by updating hctx->dispatch_busy in case of real scheduler. Reported-by: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Fixes: 6e6fcbc27e77 ("blk-mq: support batching dispatch in case of io") Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210625020248.1630497-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-18sched: Change task_struct::statePeter Zijlstra1-1/+1
Change the type and name of task_struct::state. Drop the volatile and shrink it to an 'unsigned int'. Rename it in order to find all uses such that we can use READ_ONCE/WRITE_ONCE as appropriate. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com> Acked-by: Will Deacon <will@kernel.org> Acked-by: Daniel Thompson <daniel.thompson@linaro.org> Link: https://lore.kernel.org/r/20210611082838.550736351@infradead.org
2021-06-18sched: Add get_current_state()Peter Zijlstra1-1/+1
Remove yet another few p->state accesses. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20210611082838.347475156@infradead.org
2021-06-18sched: Introduce task_is_running()Peter Zijlstra1-1/+1
Replace a bunch of 'p->state == TASK_RUNNING' with a new helper: task_is_running(p). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Davidlohr Bueso <dave@stgolabs.net> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20210611082838.222401495@infradead.org
2021-06-11blk-mq: remove blk_mq_init_sq_queueChristoph Hellwig1-22/+0
All users are gone now. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Link: https://lore.kernel.org/r/20210602065345.355274-16-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-11blk-mq: add the blk_mq_alloc_disk APIsChristoph Hellwig1-0/+19
Add a new API to allocate a gendisk including the request_queue for use with blk-mq based drivers. This is to avoid boilerplate code in drivers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Link: https://lore.kernel.org/r/20210602065345.355274-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-11blk-mq: improve the blk_mq_init_allocated_queue interfaceChristoph Hellwig1-22/+14
Don't return the passed in request_queue but a normal error code, and drop the elevator_init argument in favor of just calling elevator_init_mq directly from dm-rq. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Link: https://lore.kernel.org/r/20210602065345.355274-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-11blk-mq: factor out a blk_mq_alloc_sq_tag_set helperChristoph Hellwig1-14/+18
Factour out a helper to initialize a simple single hw queue tag_set from blk_mq_init_sq_queue. This will allow to phase out blk_mq_init_sq_queue in favor of a more symmetric and general API. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Link: https://lore.kernel.org/r/20210602065345.355274-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-03block: Do not pull requests from the scheduler when we cannot dispatch themJan Kara1-1/+1
Provided the device driver does not implement dispatch budget accounting (which only SCSI does) the loop in __blk_mq_do_dispatch_sched() pulls requests from the IO scheduler as long as it is willing to give out any. That defeats scheduling heuristics inside the scheduler by creating false impression that the device can take more IO when it in fact cannot. For example with BFQ IO scheduler on top of virtio-blk device setting blkio cgroup weight has barely any impact on observed throughput of async IO because __blk_mq_do_dispatch_sched() always sucks out all the IO queued in BFQ. BFQ first submits IO from higher weight cgroups but when that is all dispatched, it will give out IO of lower weight cgroups as well. And then we have to wait for all this IO to be dispatched to the disk (which means lot of it actually has to complete) before the IO scheduler is queried again for dispatching more requests. This completely destroys any service differentiation. So grab request tag for a request pulled out of the IO scheduler already in __blk_mq_do_dispatch_sched() and do not pull any more requests if we cannot get it because we are unlikely to be able to dispatch it. That way only single request is going to wait in the dispatch list for some tag to free. Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20210603104721.6309-1-jack@suse.cz Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-24blk-mq: Use request queue-wide tags for tagset-wide sbitmapJohn Garry1-2/+11
The tags used for an IO scheduler are currently per hctx. As such, when q->nr_hw_queues grows, so does the request queue total IO scheduler tag depth. This may cause problems for SCSI MQ HBAs whose total driver depth is fixed. Ming and Yanhui report higher CPU usage and lower throughput in scenarios where the fixed total driver tag depth is appreciably lower than the total scheduler tag depth: https://lore.kernel.org/linux-block/440dfcfc-1a2c-bd98-1161-cec4d78c6dfc@huawei.com/T/#mc0d6d4f95275a2743d1c8c3e4dc9ff6c9aa3a76b In that scenario, since the scheduler tag is got first, much contention is introduced since a driver tag may not be available after we have got the sched tag. Improve this scenario by introducing request queue-wide tags for when a tagset-wide sbitmap is used. The static sched requests are still allocated per hctx, as requests are initialised per hctx, as in blk_mq_init_request(..., hctx_idx, ...) -> set->ops->init_request(.., hctx_idx, ...). For simplicity of resizing the request queue sbitmap when updating the request queue depth, just init at the max possible size, so we don't need to deal with the possibly with swapping out a new sbitmap for old if we need to grow. Signed-off-by: John Garry <john.garry@huawei.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/1620907258-30910-3-git-send-email-john.garry@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-24blk-mq: Some tag allocation code refactoringJohn Garry1-1/+1
The tag allocation code to alloc the sbitmap pairs is common for regular bitmaps tags and shared sbitmap, so refactor into a common function. Also remove superfluous "flags" argument from blk_mq_init_shared_sbitmap(). Signed-off-by: John Garry <john.garry@huawei.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/1620907258-30910-2-git-send-email-john.garry@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-24blk-mq: clearing flush request reference in tags->rqs[]Ming Lei1-1/+34
Before we free request queue, clearing flush request reference in tags->rqs[], so that potential UAF can be avoided. Based on one patch written by David Jeffery. Tested-by: John Garry <john.garry@huawei.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: David Jeffery <djeffery@redhat.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210511152236.763464-5-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-24blk-mq: clear stale request in tags->rq[] before freeing one request poolMing Lei1-5/+41
refcount_inc_not_zero() in bt_tags_iter() still may read one freed request. Fix the issue by the following approach: 1) hold a per-tags spinlock when reading ->rqs[tag] and calling refcount_inc_not_zero in bt_tags_iter() 2) clearing stale request referred via ->rqs[tag] before freeing request pool, the per-tags spinlock is held for clearing stale ->rq[tag] So after we cleared stale requests, bt_tags_iter() won't observe freed request any more, also the clearing will wait for pending request reference. The idea of clearing ->rqs[] is borrowed from John Garry's previous patch and one recent David's patch. Tested-by: John Garry <john.garry@huawei.com> Reviewed-by: David Jeffery <djeffery@redhat.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210511152236.763464-4-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-24blk-mq: grab rq->refcount before calling ->fn in blk_mq_tagset_busy_iterMing Lei1-5/+9
Grab rq->refcount before calling ->fn in blk_mq_tagset_busy_iter(), and this way will prevent the request from being re-used when ->fn is running. The approach is same as what we do during handling timeout. Fix request use-after-free(UAF) related with completion race or queue releasing: - If one rq is referred before rq->q is frozen, then queue won't be frozen before the request is released during iteration. - If one rq is referred after rq->q is frozen, refcount_inc_not_zero() will return false, and we won't iterate over this request. However, still one request UAF not covered: refcount_inc_not_zero() may read one freed request, and it will be handled in next patch. Tested-by: John Garry <john.garry@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210511152236.763464-3-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-14blk-mq: Swap two calls in blk_mq_exit_queue()Bart Van Assche1-2/+4
If a tag set is shared across request queues (e.g. SCSI LUNs) then the block layer core keeps track of the number of active request queues in tags->active_queues. blk_mq_tag_busy() and blk_mq_tag_idle() update that atomic counter if the hctx flag BLK_MQ_F_TAG_QUEUE_SHARED is set. Make sure that blk_mq_exit_queue() calls blk_mq_tag_idle() before that flag is cleared by blk_mq_del_queue_tag_set(). Cc: Christoph Hellwig <hch@infradead.org> Cc: Ming Lei <ming.lei@redhat.com> Cc: Hannes Reinecke <hare@suse.com> Fixes: 0d2602ca30e4 ("blk-mq: improve support for shared tags maps") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210513171529.7977-1-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-14blk-mq: plug request for shared sbitmapMing Lei1-2/+3
In case of shared sbitmap, request won't be held in plug list any more sine commit 32bc15afed04 ("blk-mq: Facilitate a shared sbitmap per tagset"), this way makes request merge from flush plug list & batching submission not possible, so cause performance regression. Yanhui reports performance regression when running sequential IO test(libaio, 16 jobs, 8 depth for each job) in VM, and the VM disk is emulated with image stored on xfs/megaraid_sas. Fix the issue by recovering original behavior to allow to hold request in plug list. Cc: Yanhui Ma <yama@redhat.com> Cc: John Garry <john.garry@huawei.com> Cc: Bart Van Assche <bvanassche@acm.org> Cc: kashyap.desai@broadcom.com Fixes: 32bc15afed04 ("blk-mq: Facilitate a shared sbitmap per tagset") Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210514022052.1047665-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-29Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds1-12/+26
Pull SCSI updates from James Bottomley: "This consists of the usual driver updates (ufs, target, tcmu, smartpqi, lpfc, zfcp, qla2xxx, mpt3sas, pm80xx). The major core change is using a sbitmap instead of an atomic for queue tracking" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (412 commits) scsi: target: tcm_fc: Fix a kernel-doc header scsi: target: Shorten ALUA error messages scsi: target: Fix two format specifiers scsi: target: Compare explicitly with SAM_STAT_GOOD scsi: sd: Introduce a new local variable in sd_check_events() scsi: dc395x: Open-code status_byte(u8) calls scsi: 53c700: Open-code status_byte(u8) calls scsi: smartpqi: Remove unused functions scsi: qla4xxx: Remove an unused function scsi: myrs: Remove unused functions scsi: myrb: Remove unused functions scsi: mpt3sas: Fix two kernel-doc headers scsi: fcoe: Suppress a compiler warning scsi: libfc: Fix a format specifier scsi: aacraid: Remove an unused function scsi: core: Introduce enum scsi_disposition scsi: core: Modify the scsi_send_eh_cmnd() return value for the SDEV_BLOCK case scsi: core: Rename scsi_softirq_done() into scsi_complete() scsi: core: Remove an incorrect comment scsi: core: Make the scsi_alloc_sgtables() documentation more accurate ...
2021-04-29Merge tag 'for-5.13/block-2021-04-27' of git://git.kernel.dk/linux-blockLinus Torvalds1-1/+2
Pull block updates from Jens Axboe: "Pretty quiet round this time, which is nice. In detail: - Series revamping bounce buffer support (Christoph) - Dead code removal (Christoph, Bart) - Partition iteration revamp, now using xarray (Christoph) - Passthrough request scheduler improvements (Lin) - Series of BFQ improvements (Paolo) - Fix ioprio task iteration (Peter) - Various little tweaks and fixes (Tejun, Saravanan, Bhaskar, Max, Nikolay)" * tag 'for-5.13/block-2021-04-27' of git://git.kernel.dk/linux-block: (41 commits) blk-iocost: don't ignore vrate_min on QD contention blk-mq: Fix spurious debugfs directory creation during initialization bfq/mq-deadline: remove redundant check for passthrough request blk-mq: bypass IO scheduler's limit_depth for passthrough request block: Remove an obsolete comment from sg_io() block: move bio_list_copy_data to pktcdvd block: remove zero_fill_bio_iter block: add queue_to_disk() to get gendisk from request_queue block: remove an incorrect check from blk_rq_append_bio block: initialize ret in bdev_disk_changed block: Fix sys_ioprio_set(.which=IOPRIO_WHO_PGRP) task iteration block: remove disk_part_iter block: simplify diskstats_show block: simplify show_partition block: simplify printk_all_partitions block: simplify partition_overlaps block: simplify partition removal block: take bd_mutex around delete_partitions in del_gendisk block: refactor blk_drop_partitions block: move more syncing and invalidation to delete_partition ...
2021-04-16blk-mq: bypass IO scheduler's limit_depth for passthrough requestLin Feng1-1/+2
Commit 01e99aeca39796003 ("blk-mq: insert passthrough request into hctx->dispatch directly") gives high priority to passthrough requests and bypass underlying IO scheduler. But as we allocate tag for such request it still runs io-scheduler's callback limit_depth, while we really want is to give full sbitmap-depth capabity to such request for acquiring available tag. blktrace shows PC requests(dmraid -s -c -i) hit bfq's limit_depth: 8,0 2 0 0.000000000 39952 1,0 m N bfq [bfq_limit_depth] wr_busy 0 sync 0 depth 8 8,0 2 1 0.000008134 39952 D R 4 [dmraid] 8,0 2 2 0.000021538 24 C R [0] 8,0 2 0 0.000035442 39952 1,0 m N bfq [bfq_limit_depth] wr_busy 0 sync 0 depth 8 8,0 2 3 0.000038813 39952 D R 24 [dmraid] 8,0 2 4 0.000044356 24 C R [0] This patch introduce a new wrapper to make code not that ugly. Signed-off-by: Lin Feng <linf@wangsu.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210415033920.213963-1-linf@wangsu.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-09treewide: Change list_sort to use const pointersSami Tolvanen1-1/+2
list_sort() internally casts the comparison function passed to it to a different type with constant struct list_head pointers, and uses this pointer to call the functions, which trips indirect call Control-Flow Integrity (CFI) checking. Instead of removing the consts, this change defines the list_cmp_func_t type and changes the comparison function types of all list_sort() callers to use const pointers, thus avoiding type mismatches. Suggested-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kees Cook <keescook@chromium.org> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210408182843.1754385-10-samitolvanen@google.com
2021-03-05scsi: blk-mq: Return budget token from .get_budget callbackMing Lei1-11/+25
SCSI uses a global atomic variable to track queue depth for each LUN/request queue. This doesn't scale well when there are lots of CPU cores and the disk is very fast. It has been observed that IOPS is affected a lot by tracking queue depth via sdev->device_busy in the I/O path. Return budget token from .get_budget callback. The budget token can be passed to driver so that we can replace the atomic variable with sbitmap_queue and alleviate the scaling problems that way. Link: https://lore.kernel.org/r/20210122023317.687987-9-ming.lei@redhat.com Cc: Omar Sandoval <osandov@fb.com> Cc: Kashyap Desai <kashyap.desai@broadcom.com> Cc: Sumanesh Samanta <sumanesh.samanta@broadcom.com> Cc: Ewan D. Milne <emilne@redhat.com> Tested-by: Sumanesh Samanta <sumanesh.samanta@broadcom.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-03-05scsi: sbitmap: Move allocation hint into sbitmapMing Lei1-1/+1
Allocation hint should have belonged to sbitmap. Also, when sbitmap's depth is high and there is no need to use mulitple wakeup queues, user can benefit from percpu allocation hint too. Move allocation hint into sbitmap, then SCSI device queue can benefit from allocation hint when converting to plain sbitmap. Convert vhost/scsi.c to use sbitmap allocation with percpu alloc hint. This is more efficient than the previous approach. Link: https://lore.kernel.org/r/20210122023317.687987-5-ming.lei@redhat.com Cc: Omar Sandoval <osandov@fb.com> Cc: Kashyap Desai <kashyap.desai@broadcom.com> Cc: Sumanesh Samanta <sumanesh.samanta@broadcom.com> Cc: Ewan D. Milne <emilne@redhat.com> Cc: Mike Christie <michael.christie@oracle.com> Cc: virtualization@lists.linux-foundation.org Tested-by: Sumanesh Samanta <sumanesh.samanta@broadcom.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-03-05scsi: sbitmap: Maintain allocation round_robin in sbitmapMing Lei1-1/+1
Currently the allocation round_robin info is maintained by sbitmap_queue. However, bit allocation really belongs to sbitmap. Move it there. Link: https://lore.kernel.org/r/20210122023317.687987-3-ming.lei@redhat.com Cc: Omar Sandoval <osandov@fb.com> Cc: Kashyap Desai <kashyap.desai@broadcom.com> Cc: Sumanesh Samanta <sumanesh.samanta@broadcom.com> Cc: Ewan D. Milne <emilne@redhat.com> Cc: Hannes Reinecke <hare@suse.de> Cc: virtualization@lists.linux-foundation.org Tested-by: Sumanesh Samanta <sumanesh.samanta@broadcom.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-02-22Merge tag 'for-5.12/block-ipi-2021-02-21' of git://git.kernel.dk/linux-blockLinus Torvalds1-68/+41
Pull block IPI updates from Jens Axboe: "Avoid IRQ locking for the block IPI handling (Sebastian Andrzej Siewior)" * tag 'for-5.12/block-ipi-2021-02-21' of git://git.kernel.dk/linux-block: blk-mq: Use llist_head for blk_cpu_done blk-mq: Always complete remote completions requests in softirq smp: Process pending softirqs in flush_smp_call_function_from_idle()
2021-02-12blk-mq: Use llist_head for blk_cpu_doneSebastian Andrzej Siewior1-56/+41
With llist_head it is possible to avoid the locking (the irq-off region) when items are added. This makes it possible to add items on a remote CPU without additional locking. llist_add() returns true if the list was previously empty. This can be used to invoke the SMP function call / raise sofirq only if the first item was added (otherwise it is already pending). This simplifies the code a little and reduces the IRQ-off regions. blk_mq_raise_softirq() needs a preempt-disable section to ensure the request is enqueued on the same CPU as the softirq is raised. Some callers (USB-storage) invoke this path in preemptible context. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Daniel Wagner <dwagner@suse.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>