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2023-02-21Merge tag 'for-6.3/block-2023-02-16' of git://git.kernel.dk/linuxLinus Torvalds1-59/+91
Pull block updates from Jens Axboe: - NVMe updates via Christoph: - Small improvements to the logging functionality (Amit Engel) - Authentication cleanups (Hannes Reinecke) - Cleanup and optimize the DMA mapping cod in the PCIe driver (Keith Busch) - Work around the command effects for Format NVM (Keith Busch) - Misc cleanups (Keith Busch, Christoph Hellwig) - Fix and cleanup freeing single sgl (Keith Busch) - MD updates via Song: - Fix a rare crash during the takeover process - Don't update recovery_cp when curr_resync is ACTIVE - Free writes_pending in md_stop - Change active_io to percpu - Updates to drbd, inching us closer to unifying the out-of-tree driver with the in-tree one (Andreas, Christoph, Lars, Robert) - BFQ update adding support for multi-actuator drives (Paolo, Federico, Davide) - Make brd compliant with REQ_NOWAIT (me) - Fix for IOPOLL and queue entering, fixing stalled IO waiting on timeouts (me) - Fix for REQ_NOWAIT with multiple bios (me) - Fix memory leak in blktrace cleanup (Greg) - Clean up sbitmap and fix a potential hang (Kemeng) - Clean up some bits in BFQ, and fix a bug in the request injection (Kemeng) - Clean up the request allocation and issue code, and fix some bugs related to that (Kemeng) - ublk updates and fixes: - Add support for unprivileged ublk (Ming) - Improve device deletion handling (Ming) - Misc (Liu, Ziyang) - s390 dasd fixes (Alexander, Qiheng) - Improve utility of request caching and fixes (Anuj, Xiao) - zoned cleanups (Pankaj) - More constification for kobjs (Thomas) - blk-iocost cleanups (Yu) - Remove bio splitting from drivers that don't need it (Christoph) - Switch blk-cgroups to use struct gendisk. Some of this is now incomplete as select late reverts were done. (Christoph) - Add bvec initialization helpers, and convert callers to use that rather than open-coding it (Christoph) - Misc fixes and cleanups (Jinke, Keith, Arnd, Bart, Li, Martin, Matthew, Ulf, Zhong) * tag 'for-6.3/block-2023-02-16' of git://git.kernel.dk/linux: (169 commits) brd: use radix_tree_maybe_preload instead of radix_tree_preload block: use proper return value from bio_failfast() block: bio-integrity: Copy flags when bio_integrity_payload is cloned block: Fix io statistics for cgroup in throttle path brd: mark as nowait compatible brd: check for REQ_NOWAIT and set correct page allocation mask brd: return 0/-error from brd_insert_page() block: sync mixed merged request's failfast with 1st bio's Revert "blk-cgroup: pin the gendisk in struct blkcg_gq" Revert "blk-cgroup: pass a gendisk to blkg_lookup" Revert "blk-cgroup: delay blk-cgroup initialization until add_disk" Revert "blk-cgroup: delay calling blkcg_exit_disk until disk_release" Revert "blk-cgroup: move the cgroup information to struct gendisk" nvme-pci: remove iod use_sgls nvme-pci: fix freeing single sgl block: ublk: check IO buffer based on flag need_get_data s390/dasd: Fix potential memleak in dasd_eckd_init() s390/dasd: sort out physical vs virtual pointers usage block: Remove the ALLOC_CACHE_SLACK constant block: make kobj_type structures constant ...
2023-02-15Revert "blk-cgroup: pin the gendisk in struct blkcg_gq"Christoph Hellwig1-17/+18
This reverts commit 84d7d462b16dd5f0bf7c7ca9254bf81db2c952a2. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20230214183308.1658775-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-15Revert "blk-cgroup: pass a gendisk to blkg_lookup"Christoph Hellwig1-8/+8
This reverts commit 821e840c08ad83736eced4037cdad864e95e2584. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20230214183308.1658775-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-15Revert "blk-cgroup: move the cgroup information to struct gendisk"Christoph Hellwig1-33/+33
This reverts commit 3f13ab7c80fdb0ada86a8e3e818960bc1ccbaa59 as a patch it depends on caused a few problems. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20230214183308.1658775-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-09Revert "blk-cgroup: simplify blkg freeing from initialization failure paths"Christoph Hellwig1-7/+20
It turns out this was too soon. blkg_conf_prep does to funky locking games with the queue lock for this to work properly. This reverts commit 27b642b07a4a5eb44dffa94a5171ce468bdc46f9. Reported-by: Dan Carpenter <error27@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20230209053523.437927-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-07block, bfq: cleanup 'bfqg->online'Yu Kuai1-1/+1
After commit dfd6200a0954 ("blk-cgroup: support to track if policy is online"), there is no need to do this again in bfq. However, 'pd->online' is not protected by 'bfqd->lock', in order to make sure bfq won't see that 'pd->online' is still set after bfq_pd_offline(), clear it before bfq_pd_offline() is called. This is fine because other polices doesn't use 'pd->online' and bfq_pd_offline() will move active bfqq to root cgroup anyway. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230202134913.2364549-1-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-06blk-cgroup: fix freeing NULL blkg in blkg_createChristoph Hellwig1-1/+2
new_blkg can be NULL if the caller didn't pass in a pre-allocated blkg. Don't try to free it in that case. Fixes: 27b642b07a4a ("blk-cgroup: simplify blkg freeing from initialization failure paths") Reported-by: Yi Zhang <yi.zhang@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20230206150201.3438972-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-03blk-cgroup: move the cgroup information to struct gendiskChristoph Hellwig1-33/+33
cgroup information only makes sense on a live gendisk that allows file system I/O (which includes the raw block device). So move over the cgroup related members. 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/20230203150400.3199230-20-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-03blk-cgroup: pass a gendisk to blkg_lookupChristoph Hellwig1-8/+8
Pass a gendisk to blkg_lookup and use that to find the match as part of phasing out usage of the request_queue in the blk-cgroup code. 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/20230203150400.3199230-19-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-03blk-cgroup: pass a gendisk to pd_alloc_fnChristoph Hellwig1-5/+5
No need to the request_queue here, pass a gendisk and extract the node ids from that. 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/20230203150400.3199230-18-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-03blk-cgroup: pass a gendisk to blkcg_{de,}activate_policyChristoph Hellwig1-10/+11
Prepare for storing the blkcg information in the gendisk instead of the request_queue. 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/20230203150400.3199230-17-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-03blk-cgroup: store a gendisk to throttle in struct task_structChristoph Hellwig1-17/+15
Switch from a request_queue pointer and reference to a gendisk once for the throttle information in struct task_struct. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andreas Herrmann <aherrmann@suse.de> Link: https://lore.kernel.org/r/20230203150400.3199230-8-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-03blk-cgroup: pin the gendisk in struct blkcg_gqChristoph Hellwig1-18/+17
Currently each blkcg_gq holds a request_queue reference, which is what is used in the policies. But a lot of these interfaces will move over to use a gendisk, so store a disk in struct blkcg_gq and hold a reference to it. 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/20230203150400.3199230-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-03blk-cgroup: remove the !bdi->dev check in blkg_dev_nameChristoph Hellwig1-1/+1
bdi_dev_name already performs the same check. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20230203150400.3199230-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-03blk-cgroup: simplify blkg freeing from initialization failure pathsChristoph Hellwig1-20/+7
There is no need to delay freeing a blkg to a workqueue when freeing it after an initialization failure. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20230203150400.3199230-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-03blk-cgroup: improve error unwinding in blkg_allocChristoph Hellwig1-20/+19
Unwind only the previous initialization steps that happened in blkg_alloc using goto based unwinding. This avoids the need for the !queue special case in blkg_free and thus ensures that any blkg seens outside of blkg_alloc is always fully constructed. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20230203150400.3199230-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-02blk-cgroup: don't update io stat for root cgroupMing Lei1-0/+4
We source root cgroup stats from the system-wide stats, see blkcg_print_stat and blkcg_rstat_flush, so don't update io state for root cgroup. Fixes blkg leak issue introduced in commit 3b8cc6298724 ("blk-cgroup: Optimize blkcg_rstat_flush()") which starts to grab blkg's reference when adding iostat_cpu into percpu blkcg list, but this state won't be consumed by blkcg_rstat_flush() where the blkg reference is dropped. Tested-by: Bart van Assche <bvanassche@acm.org> Reported-by: Bart van Assche <bvanassche@acm.org> Fixes: 3b8cc6298724 ("blk-cgroup: Optimize blkcg_rstat_flush()") Cc: Tejun Heo <tj@kernel.org> Cc: Waiman Long <longman@redhat.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20230202021804.278582-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-01-30blk-cgroup: synchronize pd_free_fn() from blkg_free_workfn() and ↵Yu Kuai1-6/+29
blkcg_deactivate_policy() Currently parent pd can be freed before child pd: t1: remove cgroup C1 blkcg_destroy_blkgs blkg_destroy list_del_init(&blkg->q_node) // remove blkg from queue list percpu_ref_kill(&blkg->refcnt) blkg_release call_rcu t2: from t1 __blkg_release blkg_free schedule_work t4: deactivate policy blkcg_deactivate_policy pd_free_fn // parent of C1 is freed first t3: from t2 blkg_free_workfn pd_free_fn If policy(for example, ioc_timer_fn() from iocost) access parent pd from child pd after pd_offline_fn(), then UAF can be triggered. Fix the problem by delaying 'list_del_init(&blkg->q_node)' from blkg_destroy() to blkg_free_workfn(), and using a new disk level mutex to synchronize blkg_free_workfn() and blkcg_deactivate_policy(). Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20230119110350.2287325-4-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-01-30blk-cgroup: support to track if policy is onlineYu Kuai1-7/+17
A new field 'online' is added to blkg_policy_data to fix following 2 problem: 1) In blkcg_activate_policy(), if pd_alloc_fn() with 'GFP_NOWAIT' failed, 'queue_lock' will be dropped and pd_alloc_fn() will try again without 'GFP_NOWAIT'. In the meantime, remove cgroup can race with it, and pd_offline_fn() will be called without pd_init_fn() and pd_online_fn(). This way null-ptr-deference can be triggered. 2) In order to synchronize pd_free_fn() from blkg_free_workfn() and blkcg_deactivate_policy(), 'list_del_init(&blkg->q_node)' will be delayed to blkg_free_workfn(), hence pd_offline_fn() can be called first in blkg_destroy(), and then blkcg_deactivate_policy() will call it again, we must prevent it. The new field 'online' will be set after pd_online_fn() and will be cleared after pd_offline_fn(), in the meantime pd_offline_fn() will only be called if 'online' is set. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20230119110350.2287325-3-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-01-30blk-cgroup: dropping parent refcount after pd_free_fn() is doneYu Kuai1-2/+2
Some cgroup policies will access parent pd through child pd even after pd_offline_fn() is done. If pd_free_fn() for parent is called before child, then UAF can be triggered. Hence it's better to guarantee the order of pd_free_fn(). Currently refcount of parent blkg is dropped in __blkg_release(), which is before pd_free_fn() is called in blkg_free_work_fn() while blkg_free_work_fn() is called asynchronously. This patch make sure pd_free_fn() called from removing cgroup is ordered by delaying dropping parent refcount after calling pd_free_fn() for child. BTW, pd_free_fn() will also be called from blkcg_deactivate_policy() from deleting device, and following patches will guarantee the order. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20230119110350.2287325-2-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-01-17blk-cgroup: fix missing pd_online_fn() while activating policyYu Kuai1-0/+4
If the policy defines pd_online_fn(), it should be called after pd_init_fn(), like blkg_create(). Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20230103112833.2013432-1-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-12-14blk-iolatency: Fix memory leak on add_disk() failuresTejun Heo1-0/+2
When a gendisk is successfully initialized but add_disk() fails such as when a loop device has invalid number of minor device numbers specified, blkcg_init_disk() is called during init and then blkcg_exit_disk() during error handling. Unfortunately, iolatency gets initialized in the former but doesn't get cleaned up in the latter. This is because, in non-error cases, the cleanup is performed by del_gendisk() calling rq_qos_exit(), the assumption being that rq_qos policies, iolatency being one of them, can only be activated once the disk is fully registered and visible. That assumption is true for wbt and iocost, but not so for iolatency as it gets initialized before add_disk() is called. It is desirable to lazy-init rq_qos policies because they are optional features and add to hot path overhead once initialized - each IO has to walk all the registered rq_qos policies. So, we want to switch iolatency to lazy init too. However, that's a bigger change. As a fix for the immediate problem, let's just add an extra call to rq_qos_exit() in blkcg_exit_disk(). This is safe because duplicate calls to rq_qos_exit() become noop's. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: darklight2357@icloud.com Cc: Josef Bacik <josef@toxicpanda.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Fixes: d70675121546 ("block: introduce blk-iolatency io controller") Cc: stable@vger.kernel.org # v4.19+ Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/Y5TQ5gm3O4HXrXR3@slm.duckdns.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-12-13Merge tag 'for-6.2/block-2022-12-08' of git://git.kernel.dk/linuxLinus Torvalds1-17/+77
Pull block updates from Jens Axboe: - NVMe pull requests via Christoph: - Support some passthrough commands without CAP_SYS_ADMIN (Kanchan Joshi) - Refactor PCIe probing and reset (Christoph Hellwig) - Various fabrics authentication fixes and improvements (Sagi Grimberg) - Avoid fallback to sequential scan due to transient issues (Uday Shankar) - Implement support for the DEAC bit in Write Zeroes (Christoph Hellwig) - Allow overriding the IEEE OUI and firmware revision in configfs for nvmet (Aleksandr Miloserdov) - Force reconnect when number of queue changes in nvmet (Daniel Wagner) - Minor fixes and improvements (Uros Bizjak, Joel Granados, Sagi Grimberg, Christoph Hellwig, Christophe JAILLET) - Fix and cleanup nvme-fc req allocation (Chaitanya Kulkarni) - Use the common tagset helpers in nvme-pci driver (Christoph Hellwig) - Cleanup the nvme-pci removal path (Christoph Hellwig) - Use kstrtobool() instead of strtobool (Christophe JAILLET) - Allow unprivileged passthrough of Identify Controller (Joel Granados) - Support io stats on the mpath device (Sagi Grimberg) - Minor nvmet cleanup (Sagi Grimberg) - MD pull requests via Song: - Code cleanups (Christoph) - Various fixes - Floppy pull request from Denis: - Fix a memory leak in the init error path (Yuan) - Series fixing some batch wakeup issues with sbitmap (Gabriel) - Removal of the pktcdvd driver that was deprecated more than 5 years ago, and subsequent removal of the devnode callback in struct block_device_operations as no users are now left (Greg) - Fix for partition read on an exclusively opened bdev (Jan) - Series of elevator API cleanups (Jinlong, Christoph) - Series of fixes and cleanups for blk-iocost (Kemeng) - Series of fixes and cleanups for blk-throttle (Kemeng) - Series adding concurrent support for sync queues in BFQ (Yu) - Series bringing drbd a bit closer to the out-of-tree maintained version (Christian, Joel, Lars, Philipp) - Misc drbd fixes (Wang) - blk-wbt fixes and tweaks for enable/disable (Yu) - Fixes for mq-deadline for zoned devices (Damien) - Add support for read-only and offline zones for null_blk (Shin'ichiro) - Series fixing the delayed holder tracking, as used by DM (Yu, Christoph) - Series enabling bio alloc caching for IRQ based IO (Pavel) - Series enabling userspace peer-to-peer DMA (Logan) - BFQ waker fixes (Khazhismel) - Series fixing elevator refcount issues (Christoph, Jinlong) - Series cleaning up references around queue destruction (Christoph) - Series doing quiesce by tagset, enabling cleanups in drivers (Christoph, Chao) - Series untangling the queue kobject and queue references (Christoph) - Misc fixes and cleanups (Bart, David, Dawei, Jinlong, Kemeng, Ye, Yang, Waiman, Shin'ichiro, Randy, Pankaj, Christoph) * tag 'for-6.2/block-2022-12-08' of git://git.kernel.dk/linux: (247 commits) blktrace: Fix output non-blktrace event when blk_classic option enabled block: sed-opal: Don't include <linux/kernel.h> sed-opal: allow using IOC_OPAL_SAVE for locking too blk-cgroup: Fix typo in comment block: remove bio_set_op_attrs nvmet: don't open-code NVME_NS_ATTR_RO enumeration nvme-pci: use the tagset alloc/free helpers nvme: add the Apple shared tag workaround to nvme_alloc_io_tag_set nvme: only set reserved_tags in nvme_alloc_io_tag_set for fabrics controllers nvme: consolidate setting the tagset flags nvme: pass nr_maps explicitly to nvme_alloc_io_tag_set block: bio_copy_data_iter nvme-pci: split out a nvme_pci_ctrl_is_dead helper nvme-pci: return early on ctrl state mismatch in nvme_reset_work nvme-pci: rename nvme_disable_io_queues nvme-pci: cleanup nvme_suspend_queue nvme-pci: remove nvme_pci_disable nvme-pci: remove nvme_disable_admin_queue nvme: merge nvme_shutdown_ctrl into nvme_disable_ctrl nvme: use nvme_wait_ready in nvme_shutdown_ctrl ...
2022-12-08blk-cgroup: Fix typo in commentKemeng Shi1-2/+2
Replace assocating with associating. Replace intiailized with initialized. Signed-off-by: Kemeng Shi <shikemeng@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Reviewed-by: Mukesh Ojha <quic_mojha@quicinc.com> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20221206093307.378249-1-shikemeng@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-12-02blk-cgroup: Fix some kernel-doc commentsYang Li1-1/+1
Make the description of @gendisk to @disk in blkcg_schedule_throttle() to clear the below warnings: block/blk-cgroup.c:1850: warning: Function parameter or member 'disk' not described in 'blkcg_schedule_throttle' block/blk-cgroup.c:1850: warning: Excess function parameter 'gendisk' description in 'blkcg_schedule_throttle' Fixes: de185b56e8a6 ("blk-cgroup: pass a gendisk to blkcg_schedule_throttle") Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=3338 Reported-by: Abaci Robot <abaci@linux.alibaba.com> Signed-off-by: Yang Li <yang.lee@linux.alibaba.com> Link: https://lore.kernel.org/r/20221202011713.14834-1-yang.lee@linux.alibaba.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-30Revert "blk-cgroup: Flush stats at blkgs destruction path"Jens Axboe1-14/+1
This reverts commit dae590a6c96c799434e0ff8156ef29b88c257e60. We've had a few reports on this causing a crash at boot time, because of a reference issue. While this problem seemginly did exist before the patch and needs solving separately, this patch makes it a lot easier to trigger. Link: https://lore.kernel.org/linux-block/CA+QYu4oxiRKC6hJ7F27whXy-PRBx=Tvb+-7TQTONN8qTtV3aDA@mail.gmail.com/ Link: https://lore.kernel.org/linux-block/69af7ccb-6901-c84c-0e95-5682ccfb750c@acm.org/ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-17blk-cgroup: Flush stats at blkgs destruction pathWaiman Long1-1/+14
As noted by Michal, the blkg_iostat_set's in the lockless list hold reference to blkg's to protect against their removal. Those blkg's hold reference to blkcg. When a cgroup is being destroyed, cgroup_rstat_flush() is only called at css_release_work_fn() which is called when the blkcg reference count reaches 0. This circular dependency will prevent blkcg from being freed until some other events cause cgroup_rstat_flush() to be called to flush out the pending blkcg stats. To prevent this delayed blkcg removal, add a new cgroup_rstat_css_flush() function to flush stats for a given css and cpu and call it at the blkgs destruction path, blkcg_destroy_blkgs(), whenever there are still some pending stats to be flushed. This will ensure that blkcg reference count can reach 0 ASAP. Signed-off-by: Waiman Long <longman@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20221105005902.407297-4-longman@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-17blk-cgroup: Optimize blkcg_rstat_flush()Waiman Long1-6/+70
For a system with many CPUs and block devices, the time to do blkcg_rstat_flush() from cgroup_rstat_flush() can be rather long. It can be especially problematic as interrupt is disabled during the flush. It was reported that it might take seconds to complete in some extreme cases leading to hard lockup messages. As it is likely that not all the percpu blkg_iostat_set's has been updated since the last flush, those stale blkg_iostat_set's don't need to be flushed in this case. This patch optimizes blkcg_rstat_flush() by keeping a lockless list of recently updated blkg_iostat_set's in a newly added percpu blkcg->lhead pointer. The blkg_iostat_set is added to a lockless list on the update side in blk_cgroup_bio_start(). It is removed from the lockless list when flushed in blkcg_rstat_flush(). Due to racing, it is possible that blk_iostat_set's in the lockless list may have no new IO stats to be flushed, but that is OK. To protect against destruction of blkg, a percpu reference is gotten when putting into the lockless list and put back when removed. When booting up an instrumented test kernel with this patch on a 2-socket 96-thread system with cgroup v2, out of the 2051 calls to cgroup_rstat_flush() after bootup, 1788 of the calls were exited immediately because of empty lockless list. After an all-cpu kernel build, the ratio became 6295424/6340513. That was more than 99%. Signed-off-by: Waiman Long <longman@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20221105005902.407297-3-longman@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-17blk-cgroup: Return -ENOMEM directly in blkcg_css_alloc() error pathWaiman Long1-8/+4
For blkcg_css_alloc(), the only error that will be returned is -ENOMEM. Simplify error handling code by returning this error directly instead of setting an intermediate "ret" variable. Signed-off-by: Waiman Long <longman@redhat.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20221105005902.407297-2-longman@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-14blk-cgroup: properly pin the parent in blkcg_css_onlineChris Mason1-1/+1
blkcg_css_online is supposed to pin the blkcg of the parent, but 397c9f46ee4d refactored things and along the way, changed it to pin the css instead. This results in extra pins, and we end up leaking blkcgs and cgroups. Fixes: 397c9f46ee4d ("blk-cgroup: move blkcg_{pin,unpin}_online out of line") Signed-off-by: Chris Mason <clm@fb.com> Spotted-by: Rik van Riel <riel@surriel.com> Cc: <stable@vger.kernel.org> # v5.19+ Acked-by: Johannes Weiner <hannes@cmpxchg.org> Link: https://lore.kernel.org/r/20221114181930.2093706-1-clm@fb.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: don't update the blkg lookup hint in blkg_conf_prepChristoph Hellwig1-13/+4
blkg_conf_prep just creates a new blkg structure, there is no real need to update the lookup hint which should only be done on a successful lookup in the I/O path. Suggested-by: Tejun Heo <tj@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220927065425.257876-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: pass a gendisk to the blkg allocation helpersChristoph Hellwig1-28/+28
Prepare for storing the blkcg information in the gendisk instead of the request_queue. 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/20220921180501.1539876-18-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: pass a gendisk to blkcg_schedule_throttleChristoph Hellwig1-3/+5
Pass the gendisk to blkcg_schedule_throttle as part of moving the blk-cgroup infrastructure to be gendisk based. Remove the unused !BLK_CGROUP stub while we're at it. 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/20220921180501.1539876-17-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: pass a gendisk to blkg_destroy_allChristoph Hellwig1-9/+4
Pass the gendisk to blkg_destroy_all 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/20220921180501.1539876-16-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-throttle: pass a gendisk to blk_throtl_init and blk_throtl_exitChristoph Hellwig1-3/+3
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>
2022-09-27blk-iolatency: pass a gendisk to blk_iolatency_initChristoph Hellwig1-1/+1
Pass the gendisk to blk_iolatency_init 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/20220921180501.1539876-9-hch@lst.de [axboe: missed inline for blk_iolatency_init() and !CONFIG_BLK_CGROUP_IOLATENCY] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-ioprio: pass a gendisk to blk_ioprio_init and blk_ioprio_exitChristoph Hellwig1-2/+2
Pass the gendisk to blk_ioprio_init and blk_ioprio_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/20220921180501.1539876-8-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: pass a gendisk to blkcg_init_queue and blkcg_exit_queueChristoph Hellwig1-20/+5
Pass the gendisk to blkcg_init_disk and blkcg_exit_disk as part of moving the blk-cgroup infrastructure to be gendisk based. Also remove the rather pointless kerneldoc comments for these internal functions with a single caller each. 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/20220921180501.1539876-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: remove blkg_lookup_checkChristoph Hellwig1-26/+10
The combinations of an error check with an ERR_PTR return and a lookup with a NULL return leads to ugly handling of the return values in the callers. Just open coding the check and the lookup is much simpler. 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/20220921180501.1539876-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: cleanup the blkg_lookup family of functionsChristoph Hellwig1-23/+15
Add a fully inlined blkg_lookup as the extra two checks aren't going to generated a lot more code vs the call to the slowpath routine, and open code the hint update in the two callers that care. 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/20220921180501.1539876-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: remove open coded blkg_lookup instancesChristoph Hellwig1-3/+3
Use blkg_lookup instead of open coding it. 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/20220921180501.1539876-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: remove blk_queue_root_blkgChristoph Hellwig1-2/+1
Just open code it in the only caller and drop the unused !BLK_CGROUP stub. 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/20220921180501.1539876-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: fix error unwinding in blkcg_init_queueChristoph Hellwig1-6/+7
When blk_throtl_init fails, we need to call blk_ioprio_exit. Switch to proper goto based unwinding to fix this. 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/20220921180501.1539876-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-13blk-cgroup: Use atomic{,64}_try_cmpxchgUros Bizjak1-1/+1
Use atomic_try_cmpxchg instead of atomic_cmpxchg (*ptr, old, new) == old in blkcg_unuse_delay, blkcg_set_delay and blkcg_clear_delay and atomic64_try_cmpxchg in blkcg_scale_delay. x86 CMPXCHG instruction returns success in ZF flag, so this change saves a compare after cmpxchg (and related move instruction in front of cmpxchg). Also, atomic_try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg fails, enabling further code simplifications. No functional change intended. Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Cc: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/20220712154455.66868-1-ubizjak@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-29blk-cgroup: factor out blkcg_free_all_cpd()Jason Yan1-18/+18
To reduce some duplicated code, factor out blkcg_free_all_cpd(). No functional change. Signed-off-by: Jason Yan <yanaijie@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220629070917.3113016-3-yanaijie@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-29blk-cgroup: factor out blkcg_iostat_update()Jason Yan1-17/+20
To reduce some duplicated code, factor out blkcg_iostat_update(). No functional change. Signed-off-by: Jason Yan <yanaijie@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220629070917.3113016-2-yanaijie@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-27blk-ioprio: Convert from rqos policy to direct callJan Kara1-0/+1
Convert blk-ioprio handling from a rqos policy to a direct call from blk_mq_submit_bio(). Firstly, blk-ioprio is not much of a rqos policy anyway, it just needs a hook in bio submission path to set the bio's IO priority. Secondly, the rqos .track hook gets actually called too late for blk-ioprio purposes and introducing a special rqos hook just for blk-ioprio looks even weirder. Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220623074840.5960-7-jack@suse.cz Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-02block: fix bio_clone_blkg_association() to associate with proper blkcg_gqJan Kara1-6/+2
Commit d92c370a16cb ("block: really clone the block cgroup in bio_clone_blkg_association") changed bio_clone_blkg_association() to just clone bio->bi_blkg reference from source to destination bio. This is however wrong if the source and destination bios are against different block devices because struct blkcg_gq is different for each bdev-blkcg pair. This will result in IOs being accounted (and throttled as a result) multiple times against the same device (src bdev) while throttling of the other device (dst bdev) is ignored. In case of BFQ the inconsistency can even result in crashes in bfq_bic_update_cgroup(). Fix the problem by looking up correct blkcg_gq for the cloned bio. Reported-by: Logan Gunthorpe <logang@deltatee.com> Reported-and-tested-by: Donald Buczek <buczek@molgen.mpg.de> Fixes: d92c370a16cb ("block: really clone the block cgroup in bio_clone_blkg_association") CC: stable@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20220602081242.7731-1-jack@suse.cz Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-19blk-cgroup: delete rcu_read_lock_held() WARN_ON_ONCE()Jens Axboe1-1/+0
A previous commit got rid of unnecessary rcu_read_lock() inside the IRQ disabling queue_lock, but this debug statement was left. It's now firing since we are indeed not inside a RCU read lock, but we don't need to be as we're still preempt safe. Get rid of the check, as we have a lockdep assert for holding the queue lock right after it anyway. Link: https://lore.kernel.org/linux-block/46253c48-81cb-0787-20ad-9133afdd9e21@samsung.com/ Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Fixes: 77c570a1ea85 ("blk-cgroup: Remove unnecessary rcu_read_lock/unlock()") Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-17blk-cgroup: Remove unnecessary rcu_read_lock/unlock()Fanjun Kong1-3/+1
spin_lock_irq/spin_unlock_irq contains preempt_disable/enable(). Which can serve as RCU read-side critical region, so remove rcu_read_lock/unlock(). Signed-off-by: Fanjun Kong <bh1scw@gmail.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220516173930.159535-1-bh1scw@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>