The helper will be used in later patches for raid1/raid10/raid5, the difference is that Faulty rdev with unacknowledged bad block will not be considered blocked. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Tested-by: Mariusz Tkaczyk <mariusz.tkaczyk@linux.intel.com> Link: https://lore.kernel.org/r/20241031033114.3845582-2-yukuai1@huaweicloud.com Signed-off-by: Song Liu <song@kernel.org>
From Yu Kuai (with minor changes by Song Liu): The background is that currently bitmap is using a global spin_lock, causing lock contention and huge IO performance degradation for all raid levels. However, it's impossible to implement a new lock free bitmap with current situation that md-bitmap exposes the internal implementation with lots of exported apis. Hence bitmap_operations is invented, to describe bitmap core implementation, and a new bitmap can be introduced with a new bitmap_operations, we only need to switch to the new one during initialization. And with this we can build bitmap as kernel module, but that's not our concern for now. This version was tested with mdadm tests and lvm2 tests. This set does not introduce new errors in these tests. * md-6.12-bitmap: (42 commits) md/md-bitmap: make in memory structure internal md/md-bitmap: merge md_bitmap_enabled() into bitmap_operations md/md-bitmap: merge md_bitmap_wait_behind_writes() into bitmap_operations md/md-bitmap: merge md_bitmap_free() into bitmap_operations md/md-bitmap: merge md_bitmap_set_pages() into struct bitmap_operations md/md-bitmap: merge md_bitmap_copy_from_slot() into struct bitmap_operation. md/md-bitmap: merge get_bitmap_from_slot() into bitmap_operations md/md-bitmap: merge md_bitmap_resize() into bitmap_operations md/md-bitmap: pass in mddev directly for md_bitmap_resize() md/md-bitmap: merge md_bitmap_daemon_work() into bitmap_operations md/md-bitmap: merge bitmap_unplug() into bitmap_operations md/md-bitmap: merge md_bitmap_unplug_async() into md_bitmap_unplug() md/md-bitmap: merge md_bitmap_sync_with_cluster() into bitmap_operations md/md-bitmap: merge md_bitmap_cond_end_sync() into bitmap_operations md/md-bitmap: merge md_bitmap_close_sync() into bitmap_operations md/md-bitmap: merge md_bitmap_end_sync() into bitmap_operations md/md-bitmap: remove the parameter 'aborted' for md_bitmap_end_sync() md/md-bitmap: merge md_bitmap_start_sync() into bitmap_operations md/md-bitmap: merge md_bitmap_endwrite() into bitmap_operations md/md-bitmap: merge md_bitmap_startwrite() into bitmap_operations ... Signed-off-by: Song Liu <song@kernel.org>
For flush request, md has a special flush handling to merge concurrent
flush request into single one, however, the whole mechanism is based on
a disk level spin_lock 'mddev->lock'. And fsync can be called quite
often in some user cases, for consequence, spin lock from IO fast path can
cause performance degradation.
Fortunately, the block layer already has flush handling to merge
concurrent flush request, and it only acquires hctx level spin lock. (see
details in blk-flush.c)
This patch removes the flush handling in md, and converts to use general
block layer flush handling in underlying disks.
Flush test for 4 nvme raid10:
start 128 threads to do fsync 100000 times, on arm64, see how long it
takes.
Test script:
void* thread_func(void* arg) {
int fd = *(int*)arg;
for (int i = 0; i < FSYNC_COUNT; i++) {
fsync(fd);
}
return NULL;
}
int main() {
int fd = open("/dev/md0", O_RDWR);
if (fd < 0) {
perror("open");
exit(1);
}
pthread_t threads[THREADS];
struct timeval start, end;
gettimeofday(&start, NULL);
for (int i = 0; i < THREADS; i++) {
pthread_create(&threads[i], NULL, thread_func, &fd);
}
for (int i = 0; i < THREADS; i++) {
pthread_join(threads[i], NULL);
}
gettimeofday(&end, NULL);
close(fd);
long long elapsed = (end.tv_sec - start.tv_sec) * 1000000LL + (end.tv_usec - start.tv_usec);
printf("Elapsed time: %lld microseconds\n", elapsed);
return 0;
}
Test result: about 10 times faster:
Before this patch: 50943374 microseconds
After this patch: 5096347 microseconds
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240827110616.3860190-1-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
Now that struct bitmap_page and bitmap is not used externally anymore, move them from md-bitmap.h to md-bitmap.c (expect that dm-raid is still using define marco 'COUNTER_MAX'). Also fix some checkpatch warnings. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Link: https://lore.kernel.org/r/20240826074452.1490072-43-yukuai1@huaweicloud.com Signed-off-by: Song Liu <song@kernel.org>
The structure is empty for now, and will be used in later patches to merge in bitmap operations, so that bitmap implementation won't be exposed. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Link: https://lore.kernel.org/r/20240826074452.1490072-12-yukuai1@huaweicloud.com Signed-off-by: Song Liu <song@kernel.org>
'struct md_cluster_operations' is not modified in this driver. Constifying this structure moves some data to a read-only section, so increase overall security. On a x86_64, with allmodconfig, as an example: Before: ====== text data bss dec hex filename 51941 1442 80 53463 d0d7 drivers/md/md-cluster.o After: ===== text data bss dec hex filename 52133 1246 80 53459 d0d3 drivers/md/md-cluster.o Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/3727f3ce9693cae4e62ae6778ea13971df805479.1719173852.git.christophe.jaillet@wanadoo.fr
The md driver wants to enforce a number of flags for all devices, even
when not inheriting them from the underlying devices. To make sure these
flags survive the queue_limits_set calls that md uses to update the
queue limits without deriving them form the previous limits add a new
md_init_stacking_limits helper that calls blk_set_stacking_limits and sets
these flags.
Fixes: 1122c0c1cc71 ("block: move cache control settings out of queue->flags")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240626142637.300624-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull in block limits branch, which exists as a shared branch for both
the block and SCSI tree.
* for-6.11/block-limits: (26 commits)
block: move integrity information into queue_limits
block: invert the BLK_INTEGRITY_{GENERATE,VERIFY} flags
block: bypass the STABLE_WRITES flag for protection information
block: don't require stable pages for non-PI metadata
block: use kstrtoul in flag_store
block: factor out flag_{store,show} helper for integrity
block: remove the blk_flush_integrity call in blk_integrity_unregister
block: remove the blk_integrity_profile structure
dm-integrity: use the nop integrity profile
md/raid1: don't free conf on raid0_run failure
md/raid0: don't free conf on raid0_run failure
block: initialize integrity buffer to zero before writing it to media
block: add special APIs for run-time disabling of discard and friends
block: remove unused queue limits API
sr: convert to the atomic queue limits API
sd: convert to the atomic queue limits API
sd: cleanup zoned queue limits initialization
sd: factor out a sd_discard_mode helper
sd: simplify the disable case in sd_config_discard
sd: add a sd_disable_write_same helper
...
Move the integrity information into the queue limits so that it can be set atomically with other queue limits, and that the sysfs changes to the read_verify and write_generate flags are properly synchronized. This also allows to provide a more useful helper to stack the integrity fields, although it still is separate from the main stacking function as not all stackable devices want to inherit the integrity settings. Even with that it greatly simplifies the code in md and dm. Note that the integrity field is moved as-is into the queue limits. While there are good arguments for removing the separate blk_integrity structure, this would cause a lot of churn and might better be done at a later time if desired. However the integrity field in the queue_limits structure is now unconditional so that various ifdefs can be avoided or replaced with IS_ENABLED(). Given that tiny size of it that seems like a worthwhile trade off. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20240613084839.1044015-13-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
For different sync_action, sync_thread will use different max_sectors, see details in md_sync_max_sectors(), currently both md_do_sync() and pers->sync_request() in eatch iteration have to get the same max_sectors. Hence pass in max_sectors for pers->sync_request() to prevent redundant code. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240611132251.1967786-12-yukuai1@huaweicloud.com