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* Merge tag 'for-5.1/block-post-20190315' of git://git.kernel.dk/linux-blockLinus Torvalds2019-03-161-7/+8
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull more block layer changes from Jens Axboe: "This is a collection of both stragglers, and fixes that came in after I finalized the initial pull. This contains: - An MD pull request from Song, with a few minor fixes - Set of NVMe patches via Christoph - Pull request from Konrad, with a few fixes for xen/blkback - pblk fix IO calculation fix (Javier) - Segment calculation fix for pass-through (Ming) - Fallthrough annotation for blkcg (Mathieu)" * tag 'for-5.1/block-post-20190315' of git://git.kernel.dk/linux-block: (25 commits) blkcg: annotate implicit fall through nvme-tcp: support C2HData with SUCCESS flag nvmet: ignore EOPNOTSUPP for discard nvme: add proper write zeroes setup for the multipath device nvme: add proper discard setup for the multipath device nvme: remove nvme_ns_config_oncs nvme: disable Write Zeroes for qemu controllers nvmet-fc: bring Disconnect into compliance with FC-NVME spec nvmet-fc: fix issues with targetport assoc_list list walking nvme-fc: reject reconnect if io queue count is reduced to zero nvme-fc: fix numa_node when dev is null nvme-fc: use nr_phys_segments to determine existence of sgl nvme-loop: init nvmet_ctrl fatal_err_work when allocate nvme: update comment to make the code easier to read nvme: put ns_head ref if namespace fails allocation nvme-trace: fix cdw10 buffer overrun nvme: don't warn on block content change effects nvme: add get-feature to admin cmds tracer md: Fix failed allocation of md_register_thread It's wrong to add len to sector_nr in raid10 reshape twice ...
| * block: fix segment calculation for passthrough IOMing Lei2019-03-061-7/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | blk_recount_segments() can be called in bio_add_pc_page() for calculating how many segments this bio will has after one page is added to this bio. If the resulted segment number is beyond the queue limit, the added page will be removed. The try-and-fix policy requires blk_recount_segments(__blk_recalc_rq_segments) to not consider the segment number limit. Unfortunately bvec_split_segs() does check this limit, and causes small segment number returned to bio_add_pc_page(), then page still may be added to the bio even though segment number limit becomes broken. Fixes this issue by not considering segment number limit when calcualting bio's segment number. Fixes: dcebd755926b ("block: use bio_for_each_bvec() to compute multi-page bvec count") Cc: Christoph Hellwig <hch@lst.de> Cc: Omar Sandoval <osandov@fb.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | mm: refactor readahead defines in mm.hNikolay Borisov2019-03-121-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All users of VM_MAX_READAHEAD actually convert it to kbytes and then to pages. Define the macro explicitly as (SZ_128K / PAGE_SIZE). This simplifies the expression in every filesystem. Also rename the macro to VM_READAHEAD_PAGES to properly convey its meaning. Finally remove unused VM_MIN_READAHEAD [akpm@linux-foundation.org: fix fs/io_uring.c, per Stephen] Link: http://lkml.kernel.org/r/20181221144053.24318-1-nborisov@suse.com Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Latchesar Ionkov <lucho@ionkov.net> Cc: Dominique Martinet <asmadeus@codewreck.org> Cc: David Howells <dhowells@redhat.com> Cc: Chris Mason <clm@fb.com> Cc: Josef Bacik <josef@toxicpanda.com> Cc: David Sterba <dsterba@suse.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds2019-03-094-133/+106
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull SCSI updates from James Bottomley: "This is mostly update of the usual drivers: arcmsr, qla2xxx, lpfc, hisi_sas, target/iscsi and target/core. Additionally Christoph refactored gdth as part of the dma changes. The major mid-layer change this time is the removal of bidi commands and with them the whole of the osd/exofs driver and filesystem. This is a major simplification for block and mq in particular" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (240 commits) scsi: cxgb4i: validate tcp sequence number only if chip version <= T5 scsi: cxgb4i: get pf number from lldi->pf scsi: core: replace GFP_ATOMIC with GFP_KERNEL in scsi_scan.c scsi: mpt3sas: Add missing breaks in switch statements scsi: aacraid: Fix missing break in switch statement scsi: kill command serial number scsi: csiostor: drop serial_number usage scsi: mvumi: use request tag instead of serial_number scsi: dpt_i2o: remove serial number usage scsi: st: osst: Remove negative constant left-shifts scsi: ufs-bsg: Allow reading descriptors scsi: ufs: Allow reading descriptor via raw upiu scsi: ufs-bsg: Change the calling convention for write descriptor scsi: ufs: Remove unused device quirks Revert "scsi: ufs: disable vccq if it's not needed by UFS device" scsi: megaraid_sas: Remove a bunch of set but not used variables scsi: clean obsolete return values of eh_timed_out scsi: sd: Optimal I/O size should be a multiple of physical block size scsi: MAINTAINERS: SCSI initiator and target tweaks scsi: fcoe: make use of fip_mode enum complete ...
| * | scsi: block: remove bidi supportChristoph Hellwig2019-02-052-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | Unused now, and another field in struct request bites the dust. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
| * | scsi: block: remove req->specialChristoph Hellwig2019-02-051-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | No users left. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
| * | scsi: bsg-lib: handle bidi requests without block layer helpChristoph Hellwig2019-02-052-60/+52
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We can just stash away the second request in struct bsg_job instead of using the block layer req->next_rq field, allowing for the eventual removal of the latter. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
| * | scsi: bsg: refactor bsg_ioctlChristoph Hellwig2019-02-051-86/+72
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move all actual functionality into helpers, just leaving the dispatch in this function. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Tested-by: Benjamin Block <bblock@linux.ibm.com> Tested-by: Avri Altman <avri.altman@wdc.com> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* | | Merge tag 'io_uring-2019-03-06' of git://git.kernel.dk/linux-blockLinus Torvalds2019-03-081-8/+54
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull io_uring IO interface from Jens Axboe: "Second attempt at adding the io_uring interface. Since the first one, we've added basic unit testing of the three system calls, that resides in liburing like the other unit tests that we have so far. It'll take a while to get full coverage of it, but we're working towards it. I've also added two basic test programs to tools/io_uring. One uses the raw interface and has support for all the various features that io_uring supports outside of standard IO, like fixed files, fixed IO buffers, and polled IO. The other uses the liburing API, and is a simplified version of cp(1). This adds support for a new IO interface, io_uring. io_uring allows an application to communicate with the kernel through two rings, the submission queue (SQ) and completion queue (CQ) ring. This allows for very efficient handling of IOs, see the v5 posting for some basic numbers: https://lore.kernel.org/linux-block/20190116175003.17880-1-axboe@kernel.dk/ Outside of just efficiency, the interface is also flexible and extendable, and allows for future use cases like the upcoming NVMe key-value store API, networked IO, and so on. It also supports async buffered IO, something that we've always failed to support in the kernel. Outside of basic IO features, it supports async polled IO as well. This particular feature has already been tested at Facebook months ago for flash storage boxes, with 25-33% improvements. It makes polled IO actually useful for real world use cases, where even basic flash sees a nice win in terms of efficiency, latency, and performance. These boxes were IOPS bound before, now they are not. This series adds three new system calls. One for setting up an io_uring instance (io_uring_setup(2)), one for submitting/completing IO (io_uring_enter(2)), and one for aux functions like registrating file sets, buffers, etc (io_uring_register(2)). Through the help of Arnd, I've coordinated the syscall numbers so merge on that front should be painless. Jon did a writeup of the interface a while back, which (except for minor details that have been tweaked) is still accurate. Find that here: https://lwn.net/Articles/776703/ Huge thanks to Al Viro for helping getting the reference cycle code correct, and to Jann Horn for his extensive reviews focused on both security and bugs in general. There's a userspace library that provides basic functionality for applications that don't need or want to care about how to fiddle with the rings directly. It has helpers to allow applications to easily set up an io_uring instance, and submit/complete IO through it without knowing about the intricacies of the rings. It also includes man pages (thanks to Jeff Moyer), and will continue to grow support helper functions and features as time progresses. Find it here: git://git.kernel.dk/liburing Fio has full support for the raw interface, both in the form of an IO engine (io_uring), but also with a small test application (t/io_uring) that can exercise and benchmark the interface" * tag 'io_uring-2019-03-06' of git://git.kernel.dk/linux-block: io_uring: add a few test tools io_uring: allow workqueue item to handle multiple buffered requests io_uring: add support for IORING_OP_POLL io_uring: add io_kiocb ref count io_uring: add submission polling io_uring: add file set registration net: split out functions related to registering inflight socket files io_uring: add support for pre-mapped user IO buffers block: implement bio helper to add iter bvec pages to bio io_uring: batch io_kiocb allocation io_uring: use fget/fput_many() for file references fs: add fget_many() and fput_many() io_uring: support for IO polling io_uring: add fsync support Add io_uring IO interface
| * | | block: implement bio helper to add iter bvec pages to bioJens Axboe2019-02-281-8/+54
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For an ITER_BVEC, we can just iterate the iov and add the pages to the bio directly. For now, we grab a reference to those pages, and release them normally on IO completion. This isn't really needed for the normal case of O_DIRECT from/to a file, but some of the more esoteric use cases (like splice(2)) will unconditionally put the pipe buffer pages when the buffers are released. Until we can manage that case properly, ITER_BVEC pages are treated like normal pages in terms of reference counting. Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | | | Merge tag 'for-5.1/block-20190302' of git://git.kernel.dk/linux-blockLinus Torvalds2019-03-0817-484/+658
|\ \ \ \ | | |_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull block layer updates from Jens Axboe: "Not a huge amount of changes in this round, the biggest one is that we finally have Mings multi-page bvec support merged. Apart from that, this pull request contains: - Small series that avoids quiescing the queue for sysfs changes that match what we currently have (Aleksei) - Series of bcache fixes (via Coly) - Series of lightnvm fixes (via Mathias) - NVMe pull request from Christoph. Nothing major, just SPDX/license cleanups, RR mp policy (Hannes), and little fixes (Bart, Chaitanya). - BFQ series (Paolo) - Save blk-mq cpu -> hw queue mapping, removing a pointer indirection for the fast path (Jianchao) - fops->iopoll() added for async IO polling, this is a feature that the upcoming io_uring interface will use (Christoph, me) - Partition scan loop fixes (Dongli) - mtip32xx conversion from managed resource API (Christoph) - cdrom registration race fix (Guenter) - MD pull from Song, two minor fixes. - Various documentation fixes (Marcos) - Multi-page bvec feature. This brings a lot of nice improvements with it, like more efficient splitting, larger IOs can be supported without growing the bvec table size, and so on. (Ming) - Various little fixes to core and drivers" * tag 'for-5.1/block-20190302' of git://git.kernel.dk/linux-block: (117 commits) block: fix updating bio's front segment size block: Replace function name in string with __func__ nbd: propagate genlmsg_reply return code floppy: remove set but not used variable 'q' null_blk: fix checking for REQ_FUA block: fix NULL pointer dereference in register_disk fs: fix guard_bio_eod to check for real EOD errors blk-mq: use HCTX_TYPE_DEFAULT but not 0 to index blk_mq_tag_set->map block: optimize bvec iteration in bvec_iter_advance block: introduce mp_bvec_for_each_page() for iterating over page block: optimize blk_bio_segment_split for single-page bvec block: optimize __blk_segment_map_sg() for single-page bvec block: introduce bvec_nth_page() iomap: wire up the iopoll method block: add bio_set_polled() helper block: wire up block device iopoll method fs: add an iopoll method to struct file_operations loop: set GENHD_FL_NO_PART_SCAN after blkdev_reread_part() loop: do not print warn message if partition scan is successful block: bounce: make sure that bvec table is updated ...
| * | | block: fix updating bio's front segment sizeMing Lei2019-03-021-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the current bvec can be merged to the 1st segment, the bio's front segment size has to be updated. However, dcebd755926b doesn't consider that case, then bio's front segment size may not be correct. This patch fixes this issue. Cc: Christoph Hellwig <hch@lst.de> Cc: Omar Sandoval <osandov@fb.com> Fixes: dcebd755926b ("block: use bio_for_each_bvec() to compute multi-page bvec count") Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block: Replace function name in string with __func__Keyur Patel2019-02-281-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace hard coded function name register_blkdev with __func__, to improve robustness and to conform to the Linux kernel coding style. Issue found using checkpatch. Signed-off-by: Keyur Patel <iamkeyur96@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block: fix NULL pointer dereference in register_diskzhengbin2019-02-281-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If __device_add_disk-->bdi_register_owner-->bdi_register--> bdi_register_va-->device_create_vargs fails, bdi->dev is still NULL, __device_add_disk-->register_disk will visit bdi->dev->kobj. This patch fixes that. Signed-off-by: zhengbin <zhengbin13@huawei.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | blk-mq: use HCTX_TYPE_DEFAULT but not 0 to index blk_mq_tag_set->mapDongli Zhang2019-02-281-7/+7
| |/ / | | | | | | | | | | | | | | | | | | Replace set->map[0] with set->map[HCTX_TYPE_DEFAULT] to avoid hardcoding. Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | block: optimize blk_bio_segment_split for single-page bvecMing Lei2019-02-271-3/+9
| | | | | | | | | | | | | | | | | | | | | | | | Introduce a fast path for single-page bvec IO, then we can avoid to call bvec_split_segs() unnecessarily. Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | block: optimize __blk_segment_map_sg() for single-page bvecMing Lei2019-02-271-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | Introduce a fast path for single-page bvec IO, then blk_bvec_map_sg() can be avoided. Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | block: introduce bvec_nth_page()Ming Lei2019-02-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | Single-page bvec can often be seen in small BS workloads, so introduce bvec_nth_page() for avoiding to call nth_page() unnecessarily, which looks not cheap. Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | block: bounce: make sure that bvec table is updatedMing Lei2019-02-211-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Block bounce needs to allocate new page for doing IO, and the new page has to be updated to bvec table. Commit 6dc4f100c switches __blk_queue_bounce() to use the new bio_for_each_segment_all() interface. Unfortunately the new bio_for_each_segment_all() can't be used to update bvec table. This patch fixes this issue by retrieving bvec from the table directly, then the new allocated page can be updated to the bio. This way is safe because the cloned bio is single page bvec. Fixes: 6dc4f100c ("block: allow bio_for_each_segment_all() to iterate over multi-page bvec") Cc: Christoph Hellwig <hch@lst.de> Cc: Omar Sandoval <osandov@fb.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | block: avoid to READ fields of null bioMing Lei2019-02-191-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | rq->bio can be NULL sometimes, such as flush request, so don't read bio->bi_seg_front_size until this 'bio' is checked as valid. Cc: Bart Van Assche <bvanassche@acm.org> Reported-by: Bart Van Assche <bvanassche@acm.org> Fixes: dcebd755926b0f39dd1e ("block: use bio_for_each_bvec() to compute multi-page bvec count") Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | Merge tag 'v5.0-rc6' into for-5.1/blockJens Axboe2019-02-155-11/+57
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull in 5.0-rc6 to avoid a dumb merge conflict with fs/iomap.c. This is needed since io_uring is now based on the block branch, to avoid a conflict between the multi-page bvecs and the bits of io_uring that touch the core block parts. * tag 'v5.0-rc6': (525 commits) Linux 5.0-rc6 x86/mm: Make set_pmd_at() paravirt aware MAINTAINERS: Update the ocores i2c bus driver maintainer, etc blk-mq: remove duplicated definition of blk_mq_freeze_queue Blk-iolatency: warn on negative inflight IO counter blk-iolatency: fix IO hang due to negative inflight counter MAINTAINERS: unify reference to xen-devel list x86/mm/cpa: Fix set_mce_nospec() futex: Handle early deadlock return correctly futex: Fix barrier comment net: dsa: b53: Fix for failure when irq is not defined in dt blktrace: Show requests without sector mips: cm: reprime error cause mips: loongson64: remove unreachable(), fix loongson_poweroff(). sit: check if IPv6 enabled before calling ip6_err_gen_icmpv6_unreach() geneve: should not call rt6_lookup() when ipv6 was disabled KVM: nVMX: unconditionally cancel preemption timer in free_nested (CVE-2019-7221) KVM: x86: work around leak of uninitialized stack contents (CVE-2019-7222) kvm: fix kvm_ioctl_create_device() reference counting (CVE-2019-6974) signal: Better detection of synchronous signals ...
| * | | block: kill BLK_MQ_F_SG_MERGEMing Lei2019-02-151-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | QUEUE_FLAG_NO_SG_MERGE has been killed, so kill BLK_MQ_F_SG_MERGE too. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block: kill QUEUE_FLAG_NO_SG_MERGEMing Lei2019-02-153-29/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since bdced438acd83ad83a6c ("block: setup bi_phys_segments after splitting"), physical segment number is mainly figured out in blk_queue_split() for fast path, and the flag of BIO_SEG_VALID is set there too. Now only blk_recount_segments() and blk_recalc_rq_segments() use this flag. Basically blk_recount_segments() is bypassed in fast path given BIO_SEG_VALID is set in blk_queue_split(). For another user of blk_recalc_rq_segments(): - run in partial completion branch of blk_update_request, which is an unusual case - run in blk_cloned_rq_check_limits(), still not a big problem if the flag is killed since dm-rq is the only user. Multi-page bvec is enabled now, not doing S/G merging is rather pointless with the current setup of the I/O path, as it isn't going to save you a significant amount of cycles. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block: enable multipage bvecsMing Lei2019-02-151-7/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch pulls the trigger for multi-page bvecs. Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block: allow bio_for_each_segment_all() to iterate over multi-page bvecMing Lei2019-02-152-11/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces one extra iterator variable to bio_for_each_segment_all(), then we can allow bio_for_each_segment_all() to iterate over multi-page bvec. Given it is just one mechannical & simple change on all bio_for_each_segment_all() users, this patch does tree-wide change in one single patch, so that we can avoid to use a temporary helper for this conversion. Reviewed-by: Omar Sandoval <osandov@fb.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block: use bio_for_each_bvec() to map sgMing Lei2019-02-151-20/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is more efficient to use bio_for_each_bvec() to map sg, meantime we have to consider splitting multipage bvec as done in blk_bio_segment_split(). Reviewed-by: Omar Sandoval <osandov@fb.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block: use bio_for_each_bvec() to compute multi-page bvec countMing Lei2019-02-151-20/+83
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | First it is more efficient to use bio_for_each_bvec() in both blk_bio_segment_split() and __blk_recalc_rq_segments() to compute how many multi-page bvecs there are in the bio. Secondly once bio_for_each_bvec() is used, the bvec may need to be splitted because its length can be very longer than max segment size, so we have to split the big bvec into several segments. Thirdly when splitting multi-page bvec into segments, the max segment limit may be reached, so the bio split need to be considered under this situation too. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block: don't use bio->bi_vcnt to figure out segment numberMing Lei2019-02-151-7/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is wrong to use bio->bi_vcnt to figure out how many segments there are in the bio even though CLONED flag isn't set on this bio, because this bio may be splitted or advanced. So always use bio_segments() in blk_recount_segments(), and it shouldn't cause any performance loss now because the physical segment number is figured out in blk_queue_split() and BIO_SEG_VALID is set meantime since bdced438acd83ad83a6c ("block: setup bi_phys_segments after splitting"). Reviewed-by: Omar Sandoval <osandov@fb.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Fixes: 76d8137a3113 ("blk-merge: recaculate segment if it isn't less than max segments") Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block: avoid setting none scheduler if it's already noneAleksei Zakharov2019-02-111-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's no reason to freeze queue and remove scheduler if there's no scheduler already. Signed-off-by: Aleksei Zakharov <zakharov.a.g@yandex.ru> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block: avoid setting wbt_lat_usec to current valueAleksei Zakharov2019-02-111-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's no reason to set wbt min lat and freeze request queue if current value is the same. Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Aleksei Zakharov <zakharov.a.g@yandex.ru> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | blk-sysfs: Rework documention of __blk_release_queueMarcos Paulo de Souza2019-02-101-12/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Notes section of the comment was removed, because now blk_release_queue can only be executed from blk_cleanup_queue (being called when the q->kobj reaches zero), and also blk_init_queue was removed in a1ce35fa4985. Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | blk-cgroup: Fix doc related to blkcg_exit_queueMarcos Paulo de Souza2019-02-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since 4cf6324b17e9, a portion of function blk_cleanup_queue was moved to a newly created function called blk_exit_queue, including the call of blkcg_exit_queue. So, adjust the documenation according. Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block: kill QUEUE_FLAG_FLUSH_NQJens Axboe2019-02-092-10/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have various helpers for setting/clearing this flag, and also a helper to check if the queue supports queueable flushes or not. But nobody uses them anymore, kill it with fire. Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block: avoid setting nr_requests to current valueAleksei Zakharov2019-02-081-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's no reason to freeze queue and set nr_requests value if current value is the same. Signed-off-by: Aleksei Zakharov <zakharov.a.g@yandex.ru> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | blk-mq: save default hctx into ctx->hctxs for not-supported typeJianchao Wang2019-02-012-9/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, we check whether the hctx type is supported every time in hot path. Actually, this is not necessary, we could save the default hctx into ctx->hctxs if the type is not supported when map swqueues and use it directly with ctx->hctxs[type]. We also needn't check whether the poll is enabled or not, because the caller would clear the REQ_HIPRI in that case. Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | blk-mq: save queue mapping result into ctx directlyJianchao Wang2019-02-015-8/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, the queue mapping result is saved in a two-dimensional array. In the hot path, to get a hctx, we need do following: q->queue_hw_ctx[q->tag_set->map[type].mq_map[cpu]] This isn't very efficient. We could save the queue mapping result into ctx directly with different hctx type, like, ctx->hctxs[type] Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block, bfq: fix in-service-queue check for queue mergingPaolo Valente2019-01-312-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a new I/O request arrives for a bfq_queue, say Q, bfq checks whether that request is close to (a) the head request of some other queue waiting to be served, or (b) the last request dispatched for the in-service queue (in case Q itself is not the in-service queue) If a queue, say Q2, is found for which the above condition holds, then bfq merges Q and Q2, to hopefully get a more sequential I/O in the resulting merged queue, and thus a possibly higher throughput. Case (b) is checked by comparing the new request for Q with the last request dispatched, assuming that the latter necessarily belonged to the in-service queue. Unfortunately, this assumption is no longer always correct, since commit d0edc2473be9 ("block, bfq: inject other-queue I/O into seeky idle queues on NCQ flash"). When the assumption does not hold, queues that must not be merged may be merged, causing unexpected loss of control on per-queue service guarantees. This commit solves this problem by adding an extra field, which stores the actual last request dispatched for the in-service queue, and by using this new field to correctly check case (b). Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block, bfq: do not overcharge writes in asymmetric scenariosPaolo Valente2019-01-311-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Writes tend to starve reads. bfq counters this problem by overcharging writes with an inflated service w.r.t. the actual service (number of sector written) they receive. Yet his overcharging is useless, and actually causes unfairness in the opposite direction, when bfq happens to be enforcing strong I/O control. bfq does this enforcing when the scenario is asymmetric, i.e., when some bfq_queue or group of bfq_queues is to be granted a different bandwidth than some other bfq_queue or group of bfq_queues. So, in such a scenario, this commit disables write overcharging. Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block, bfq: port commit "cfq-iosched: improve hw_tag detection"Paolo Valente2019-01-311-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The original commit is commit 1a1238a7dd48 ("cfq-iosched: improve hw_tag detection") and has the following commit message: If active queue hasn't enough requests and idle window opens, cfq will not dispatch sufficient requests to hardware. In such situation, current code will zero hw_tag. But this is because cfq doesn't dispatch enough requests instead of hardware queue doesn't work. Don't zero hw_tag in such case. Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block, bfq: reduce threshold for detecting command queueingPaolo Valente2019-01-311-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | bfq simple heuristic from cfq for detecting whether the drive performs command queueing: check whether the average number of in-flight requests is above a given threshold. Unfortunately this heuristic does fail to detect queueing (on drives with queueing) if processes doing I/O are few and issue I/O with a low depth. To reduce false negatives, this commit lowers the threshold. Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block, bfq: fix queue removal from weights treePaolo Valente2019-01-312-7/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | bfq maintains an ordered list, through a red-black tree, of unique weights of active bfq_queues. This list is used to detect whether there are active queues with differentiated weights. The weight of a queue is removed from the list when both the following two conditions become true: (1) the bfq_queue is flagged as inactive (2) the has no in-flight request any longer; Unfortunately, in the rare cases where condition (2) becomes true before condition (1), the removal fails, because the function to remove the weight of the queue (bfq_weights_tree_remove) is rightly invoked in the path that deactivates the bfq_queue, but mistakenly invoked *before* the function that actually performs the deactivation (bfq_deactivate_bfqq). This commits moves the invocation of bfq_weights_tree_remove for condition (1) to after bfq_deactivate_bfqq. As a consequence of this move, it is necessary to add a further reference to the queue when the weight of a queue is added, because the queue might otherwise be freed before bfq_weights_tree_remove is invoked. This commit adds this reference and makes all related modifications. Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block, bfq: fix sequential rq detection in rate estimationPaolo Valente2019-01-311-5/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In bfq_update_peak_rate, to check whether an I/O request rq is sequential, only the seek distance of rq w.r.t. the last request dispatched is controlled. This is not sufficient for non-rotational storage, where the size of rq is at least as relevant. This commit adds the missing control. Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block, bfq: unconditionally plug I/O in asymmetric scenariosPaolo Valente2019-01-311-181/+165
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | bfq detects the creation of multiple bfq_queues shortly after each other, namely a burst of queue creations in the terminology used in the code. If the burst is large, then no queue in the burst is granted - either I/O-dispatch plugging when the queue remains temporarily idle while in service; - or weight raising, because it causes even longer plugging. In fact, such a plugging tends to lower throughput, while these bursts are typically due to applications or services that spawn multiple processes, to reach a common goal as soon as possible. Examples are a "git grep" or the booting of a system. Unfortunately, disabling plugging may cause a loss of service guarantees in asymmetric scenarios, i.e., if queue weights are differentiated or if more than one group is active. This commit addresses this issue by no longer disabling I/O-dispatch plugging for queues in large bursts. Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block, bfq: do not plug I/O of in-service queue when harmfulPaolo Valente2019-01-311-14/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the in-service bfq_queue is sync and remains temporarily idle, then I/O dispatching (from other queues) may be plugged. It may be dome for two reasons: either to boost throughput, or to preserve the bandwidth share of the in-service queue. In the first case, if the I/O of the in-service queue, when it finally arrives, consists only of one small I/O request, then it makes sense to plug even the I/O of the in-service queue. In fact, serving such a small request immediately is likely to lower throughput instead of boosting it, whereas waiting a little bit is likely to let that request grow, thanks to request merging, and become more profitable in terms of throughput (this is likely to happen exactly because the I/O of the queue has been detected to boost throughput). On the opposite end, if I/O dispatching is being plugged only to preserve the bandwidth of the in-service queue, then it would be better not to plug also the I/O of the in-service queue, because such a plugging is likely to cause only loss of bandwidth for the queue. Unfortunately, no distinction is made between the two cases, and the I/O of the in-service queue is always plugged in case just a small I/O request arrives. This commit draws this missing distinction and does not perform harmful plugging. Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block, bfq: split function bfq_better_to_idlePaolo Valente2019-01-311-73/+82
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a preparatory commit for commits that need to check only one of the two main reasons for idling. This change should also improve the quality of the code a little bit, by splitting a function that contains very long, non-trivial and little related comments. Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block, bfq: consider also ioprio classes in symmetry detectionPaolo Valente2019-01-313-47/+59
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In asymmetric scenarios, i.e., when some bfq_queue or bfq_group needs to be guaranteed a different bandwidth than other bfq_queues or bfq_groups, these service guaranteed can be provided only by plugging I/O dispatch, completely or partially, when the queue in service remains temporarily empty. A case where asymmetry is particularly strong is when some active bfq_queues belong to a higher-priority class than some other active bfq_queues. Unfortunately, this important case is not considered at all in the code for detecting asymmetric scenarios. This commit adds the missing logic. Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block, bfq: remove case of redirected bic from insert_requestPaolo Valente2019-01-311-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before commit 18e5a57d7987 ("block, bfq: postpone rq preparation to insert or merge"), the destination queue for a request was chosen by a different hook than the one that then inserted the request. So, between the execution of the two hooks, the bic of the process generating the request could happen to be redirected to a different bfq_queue. As a consequence, the destination bfq_queue stored in the request could be wrong. Such an event does not need to ba handled any longer. Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block, bfq: make sure queue budgets are not below service receivedPaolo Valente2019-01-311-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With some unlucky sequences of events, the function bfq_updated_next_req updates the current budget of a bfq_queue to a lower value than the service received by the queue using such a budget. Unfortunately, if this happens, then the return value of the function bfq_bfqq_budget_left becomes inconsistent. This commit solves this problem by lower-bounding the budget computed in bfq_updated_next_req to the service currently charged to the queue. Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block, bfq: avoid selecting a queue w/o budgetPaolo Valente2019-01-311-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To boost throughput on devices with internal queueing and in scenarios where device idling is not strictly needed, bfq immediately starts serving a new bfq_queue if the in-service bfq_queue remains without pending I/O, even if new I/O may arrive soon for the latter queue. Then, if such I/O actually arrives soon, bfq preempts the new in-service bfq_queue so as to give the previous queue a chance to go on being served (in case the previous queue should actually be the one to be served, according to its timestamps). However, the in-service bfq_queue, say Q, may also be without further budget when it remains also pending I/O. Since bfq changes budgets dynamically to fit the needs of bfq_queues, this happens more often than one may expect. If this happens, then there is no point in trying to go on serving Q when new I/O arrives for it soon: Q would be expired immediately after being selected for service. This would only cause useless overhead. This commit avoids such a useless selection. Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | block, bfq: do not consider interactive queues in srt filteringPaolo Valente2019-01-311-10/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The speed at which a bfq_queue receives I/O is one of the parameters by which bfq decides whether the queue is soft real-time (i.e., whether the queue contains the I/O of a soft real-time application). In particular, when a bfq_queue remains without outstanding I/O requests, bfq computes the minimum time instant, named soft_rt_next_start, at which the next request of the queue may arrive for the queue to be deemed as soft real time. Unfortunately this filtering may cause problems with a queue in interactive weight raising. In fact, such a queue may be conveying the I/O needed to load a soft real-time application. The latter will actually exhibit a soft real-time I/O pattern after it finally starts doing its job. But, if soft_rt_next_start is updated for an interactive bfq_queue, and the queue has received a lot of service before remaining with no outstanding request (likely to happen on a fast device), then soft_rt_next_start is assigned such a high value that, for a very long time, the queue is prevented from being possibly considered as soft real time. This commit removes the updating of soft_rt_next_start for bfq_queues in interactive weight raising. Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>