user/sven/linux.git/drivers/md/raid1.c, branch v5.11.9

block: remove the request_queue argument to the block_bio_remap tracepoint

2020-12-04T16:42:00Z

The request_queue can trivially be derived from the bio. Signed-off-by: Christoph Hellwig Reviewed-by: Damien Le Moal Reviewed-by: Hannes Reinecke Reviewed-by: Chaitanya Kulkarni Acked-by: Tejun Heo Signed-off-by: Jens Axboe

writeback: remove bdi->congested_fn

2020-07-08T23:20:46Z

Except for pktdvd, the only places setting congested bits are file systems that allocate their own backing_dev_info structures. And pktdvd is a deprecated driver that isn't useful in stack setup either. So remove the dead congested_fn stacking infrastructure. Signed-off-by: Christoph Hellwig Acked-by: Song Liu Acked-by: David Sterba [axboe: fixup unused variables in bcache/request.c] Signed-off-by: Jens Axboe

block: rename generic_make_request to submit_bio_noacct

2020-07-01T13:27:24Z

generic_make_request has always been very confusingly misnamed, so rename it to submit_bio_noacct to make it clear that it is submit_bio minus accounting and a few checks. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

md/raid1: release pending accounting for an I/O only after write-behind is also finished

2020-05-13T18:22:31Z

When using RAID1 and write-behind, md can deadlock when errors occur. With write-behind, r1bio structs can be accounted by raid1 as queued but not counted as pending. The pending count is dropped when the original bio is returned complete but write-behind for the r1bio may still be active. This breaks the accounting used in some conditions to know when the raid1 md device has reached an idle state. It can result in calls to freeze_array deadlocking. freeze_array will never complete from a negative "unqueued" value being calculated due to a queued count larger than the pending count. To properly account for write-behind, move the call to allow_barrier from call_bio_endio to raid_end_bio_io. When using write-behind, md can call call_bio_endio before all write-behind I/O is complete. Using raid_end_bio_io for the point to call allow_barrier will release the pending count at a point where all I/O for an r1bio, even write-behind, is done. Signed-off-by: David Jeffery Signed-off-by: Song Liu

md/raid1: introduce wait_for_serialization

2020-01-13T19:44:10Z

Previously, we call check_and_add_serial when serialization is enabled for write IO, but it could allocate and free memory back and forth. Now, let's just get an element from memory pool with the new function, then insert node to rb tree if no collision happens. Signed-off-by: Guoqing Jiang Signed-off-by: Song Liu

md/raid1: use bucket based mechanism for IO serialization

2020-01-13T19:44:10Z

Since raid1 had already used bucket based mechanism to reduce the conflict between write IO and resync IO, it is possible to speed up performance for io serialization with refer to the same mechanism. To align with the barrier bucket mechanism, we created arrays (with the same number of BARRIER_BUCKETS_NR) for spinlock, rb tree and waitqueue. Then we can reduce lock competition with multiple spinlocks, boost search performance with multiple rb trees and also reduce thundering herd problem with multiple waitqueues. Signed-off-by: Guoqing Jiang Signed-off-by: Song Liu

md: introduce a new struct for IO serialization

2020-01-13T19:44:10Z

Obviously, IO serialization could cause the degradation of performance a lot. In order to reduce the degradation, so a rb interval tree is added in raid1 to speed up the check of collision. So, a rb root is needed in md_rdev, then abstract all the serialize related members to a new struct (serial_in_rdev), embed it into md_rdev. Of course, we need to free the struct if it is not needed anymore, so rdev/rdevs_uninit_serial are added accordingly. And they should be called when destroty memory pool or can't alloc memory. And we need to consider to call mddev_destroy_serial_pool in case serialize_policy/write-behind is disabled, bitmap is destroyed or in __md_stop_writes. Signed-off-by: Guoqing Jiang Signed-off-by: Song Liu

raid1: serialize the overlap write

2020-01-13T19:44:09Z

Before dispatch write bio, raid1 array which enables serialize_policy need to check if overlap exists between this bio and previous on-flying bios. If there is overlap, then it has to wait until the collision is disappeared. Signed-off-by: Guoqing Jiang Signed-off-by: Song Liu

md: rename wb stuffs

2020-01-13T19:44:09Z

Previously, wb_info_pool and wb_list stuffs are introduced to address potential data inconsistence issue for write behind device. Now rename them to serial related name, since the same mechanism will be used to address reorder overlap write issue for raid1. Signed-off-by: Guoqing Jiang Signed-off-by: Song Liu

md: raid1: check rdev before reference in raid1_sync_request func

2019-12-11T18:36:13Z

In raid1_sync_request func, rdev should be checked before reference. Signed-off-by: Zhiqiang Liu Signed-off-by: Song Liu