user/sven/linux.git/include/linux/genhd.h, branch v5.7.11

Merge tag 'for-5.7/block-2020-03-29' of git://git.kernel.dk/linux-block

2020-03-30T18:20:13Z

Pull block updates from Jens Axboe: - Online capacity resizing (Balbir) - Number of hardware queue change fixes (Bart) - null_blk fault injection addition (Bart) - Cleanup of queue allocation, unifying the node/no-node API (Christoph) - Cleanup of genhd, moving code to where it makes sense (Christoph) - Cleanup of the partition handling code (Christoph) - disk stat fixes/improvements (Konstantin) - BFQ improvements (Paolo) - Various fixes and improvements * tag 'for-5.7/block-2020-03-29' of git://git.kernel.dk/linux-block: (72 commits) block: return NULL in blk_alloc_queue() on error block: move bio_map_* to blk-map.c Revert "blkdev: check for valid request queue before issuing flush" block: simplify queue allocation bcache: pass the make_request methods to blk_queue_make_request null_blk: use blk_mq_init_queue_data block: add a blk_mq_init_queue_data helper block: move the ->devnode callback to struct block_device_operations block: move the part_stat* helpers from genhd.h to a new header block: move block layer internals out of include/linux/genhd.h block: move guard_bio_eod to bio.c block: unexport get_gendisk block: unexport disk_map_sector_rcu block: unexport disk_get_part block: mark part_in_flight and part_in_flight_rw static block: mark block_depr static block: factor out requeue handling from dispatch code block/diskstats: replace time_in_queue with sum of request times block/diskstats: accumulate all per-cpu counters in one pass block/diskstats: more accurate approximation of io_ticks for slow disks ...

block: move the ->devnode callback to struct block_device_operations

2020-03-27T15:50:05Z

There really isn't any good reason to stash a method directly into struct gendisk. Move it together with the other block device operations. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

block: move the part_stat* helpers from genhd.h to a new header

2020-03-25T15:50:09Z

These macros are just used by a few files. Move them out of genhd.h, which is included everywhere into a new standalone header. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

block: move block layer internals out of include/linux/genhd.h

2020-03-25T15:50:08Z

None of this needs to be exposed to drivers. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

block: mark part_in_flight and part_in_flight_rw static

2020-03-25T15:50:08Z

Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

block: mark block_depr static

2020-03-25T15:50:08Z

Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

block/diskstats: replace time_in_queue with sum of request times

2020-03-25T14:49:12Z

Column "time_in_queue" in diskstats is supposed to show total waiting time of all requests. I.e. value should be equal to the sum of times from other columns. But this is not true, because column "time_in_queue" is counted separately in jiffies rather than in nanoseconds as other times. This patch removes redundant counter for "time_in_queue" and shows total time of read, write, discard and flush requests. Signed-off-by: Konstantin Khlebnikov Signed-off-by: Jens Axboe

block/diskstats: accumulate all per-cpu counters in one pass

2020-03-25T14:49:10Z

Reading /proc/diskstats iterates over all cpus for summing each field. It's faster to sum all fields in one pass. Hammering /proc/diskstats with fio shows 2x performance improvement: fio --name=test --numjobs=$JOBS --filename=/proc/diskstats \ --size=1k --bs=1k --fallocate=none --create_on_open=1 \ --time_based=1 --runtime=10 --invalidate=0 --group_report JOBS=1 JOBS=10 Before: 7k iops 64k iops After: 18k iops 120k iops Also this way code is more compact: add/remove: 1/0 grow/shrink: 0/2 up/down: 194/-1540 (-1346) Function old new delta part_stat_read_all - 194 +194 diskstats_show 1344 631 -713 part_stat_show 1219 392 -827 Total: Before=14966947, After=14965601, chg -0.01% Signed-off-by: Konstantin Khlebnikov Signed-off-by: Jens Axboe

block/diskstats: more accurate approximation of io_ticks for slow disks

2020-03-25T14:49:08Z

Currently io_ticks is approximated by adding one at each start and end of requests if jiffies counter has changed. This works perfectly for requests shorter than a jiffy or if one of requests starts/ends at each jiffy. If disk executes just one request at a time and they are longer than two jiffies then only first and last jiffies will be accounted. Fix is simple: at the end of request add up into io_ticks jiffies passed since last update rather than just one jiffy. Example: common HDD executes random read 4k requests around 12ms. fio --name=test --filename=/dev/sdb --rw=randread --direct=1 --runtime=30 & iostat -x 10 sdb Note changes of iostat's "%util" 8,43% -> 99,99% before/after patch: Before: Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util sdb 0,00 0,00 82,60 0,00 330,40 0,00 8,00 0,96 12,09 12,09 0,00 1,02 8,43 After: Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util sdb 0,00 0,00 82,50 0,00 330,00 0,00 8,00 1,00 12,10 12,10 0,00 12,12 99,99 Now io_ticks does not loose time between start and end of requests, but for queue-depth > 1 some I/O time between adjacent starts might be lost. For load estimation "%util" is not as useful as average queue length, but it clearly shows how often disk queue is completely empty. Fixes: 5b18b5a73760 ("block: delete part_round_stats and switch to less precise counting") Signed-off-by: Konstantin Khlebnikov Reviewed-by: Ming Lei Signed-off-by: Jens Axboe

block: move the various x86 Unix label formats out of genhd.h

2020-03-24T13:57:08Z

All these are just used in block/partitions/msdos.c, so move them out of the genhd.h driver included by every driver. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe