From: Alexander Atanasov <alexander.atana...@virtuozzo.com> currently threads do
old_flags = current->flags; current->flags |= ploop flags; ... current->flags = old_flags; this can break process flags To fix this use current_restore_flags(..) macro which only removes our flags and it preserves any other flags. https://virtuozzo.atlassian.net/browse/VSTOR-98626 Signed-off-by: Alexander Atanasov <alexander.atana...@virtuozzo.com> ====== Patchset description: ploop: optimistations and scalling Ploop processes requsts in a different threads in parallel where possible which results in significant improvement in performance and makes further optimistations possible. Known bugs: - delayed metadata writeback is not working and is missing error handling - patch to disable it until fixed - fast path is not working - causes rcu lockups - patch to disable it Further improvements: - optimize md pages lookups Alexander Atanasov (50): dm-ploop: md_pages map all pages at creation time dm-ploop: Use READ_ONCE/WRITE_ONCE to access md page data dm-ploop: fsync after all pios are sent dm-ploop: move md status to use proper bitops dm-ploop: convert wait_list and wb_batch_llist to use lockless lists dm-ploop: convert enospc handling to use lockless lists dm-ploop: convert suspended_pios list to use lockless list dm-ploop: convert the rest of the lists to use llist variant dm-ploop: combine processing of pios thru prepare list and remove fsync worker dm-ploop: move from wq to kthread dm-ploop: move preparations of pios into the caller from worker dm-ploop: fast path execution for reads dm-ploop: do not use a wrapper for set_bit to make a page writeback dm-ploop: BAT use only one list for writeback dm-ploop: make md writeback timeout to be per page dm-ploop: add interface to disable bat writeback delay dm-ploop: convert wb_batch_list to lockless variant dm-ploop: convert high_prio to status dm-ploop: split cow processing into two functions dm-ploop: convert md page rw lock to spin lock dm-ploop: convert bat_rwlock to bat_lock spinlock dm-ploop: prepare bat updates under bat_lock dm-ploop: make ploop_bat_write_complete ready for parallel pio completion dm-ploop: make ploop_submit_metadata_writeback return number of requests sent dm-ploop: introduce pio runner threads dm-ploop: add pio list ids to be used when passing pios to runners dm-ploop: process pios via runners dm-ploop: disable metadata writeback delay dm-ploop: disable fast path dm-ploop: use lockless lists for chained cow updates list dm-ploop: use lockless lists for data ready pios dm-ploop: give runner threads better name dm-ploop: resize operation - add holes bitmap locking dm-ploop: remove unnecessary operations dm-ploop: use filp per thread dm-ploop: catch if we try to advance pio past bio end dm-ploop: support REQ_FUA for data pios dm-ploop: proplerly access nr_bat_entries dm-ploop: fix locking and improve error handling when submitting pios dm-ploop: fix how ENOTBLK is handled dm-ploop: sync when suspended or stopping dm-ploop: rework bat completion logic dm-ploop: rework logic in pio processing dm-ploop: end fsync pios in parallel dm-ploop: make filespace preallocations async dm-ploop: resubmit enospc pios from dispatcher thread dm-ploop: dm-ploop: simplify discard completion dm-ploop: use GFP_ATOMIC instead of GFP_NOIO dm-ploop: fix locks used in mixed context dm-ploop: fix how current flags are managed inside threads Andrey Zhadchenko (13): dm-ploop: do not flush after metadata writes dm-ploop: set IOCB_DSYNC on all FUA requests dm-ploop: remove extra ploop_cluster_is_in_top_delta() dm-ploop: introduce per-md page locking dm-ploop: reduce BAT accesses on discard completion dm-ploop: simplify llseek dm-ploop: speed up ploop_prepare_bat_update() dm-ploop: make new allocations immediately visible in BAT dm-ploop: drop ploop_cluster_is_in_top_delta() dm-ploop: do not wait for BAT update for non-FUA requests dm-ploop: add delay for metadata writeback dm-ploop: submit all postponed metadata on REQ_OP_FLUSH dm-ploop: handle REQ_PREFLUSH Feature: dm-ploop: ploop target driver --- drivers/md/dm-ploop-map.c | 26 +++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-) diff --git a/drivers/md/dm-ploop-map.c b/drivers/md/dm-ploop-map.c index 0b934b83a176..4669efed3cc0 100644 --- a/drivers/md/dm-ploop-map.c +++ b/drivers/md/dm-ploop-map.c @@ -2149,6 +2149,7 @@ void ploop_resubmit_enospc_pios(struct ploop *ploop) ploop_submit_embedded_pios(ploop, llist_reverse_order(enospc_pending)); } +#define PLOOP_PFLAGS (PF_IO_THREAD|PF_LOCAL_THROTTLE|PF_MEMALLOC_NOIO) void do_ploop_run_work(struct ploop *ploop) { LLIST_HEAD(deferred_pios); @@ -2162,7 +2163,7 @@ void do_ploop_run_work(struct ploop *ploop) int npios; int force_md_update; - current->flags |= PF_IO_THREAD|PF_LOCAL_THROTTLE|PF_MEMALLOC_NOIO; + current->flags |= PLOOP_PFLAGS; if (ploop->submit_enospc) { ploop->submit_enospc = false; @@ -2200,10 +2201,10 @@ void do_ploop_run_work(struct ploop *ploop) * put stick in the wheel - wait for all pios to be executed before doing metadata * we could gain a bit more iops if we can skip this wait but for now we can not */ - current->flags = old_flags; + current_restore_flags(old_flags, PLOOP_PFLAGS); wait_event_interruptible(ploop->dispatcher_wq_data, (!ploop_runners_have_pending(ploop))); - current->flags |= PF_IO_THREAD|PF_LOCAL_THROTTLE|PF_MEMALLOC_NOIO; + current->flags |= PLOOP_PFLAGS; /* if we have a flush we must sync md data too */ force_md_update = !!llflush_pios | ploop->force_md_writeback; @@ -2211,25 +2212,25 @@ void do_ploop_run_work(struct ploop *ploop) if (npios) { /* wait for metadata writeback to complete */ - current->flags = old_flags; + current_restore_flags(old_flags, PLOOP_PFLAGS); /* First wait all pios to be processed */ wait_event_interruptible(ploop->dispatcher_wq_data, (!ploop_runners_have_pending(ploop))); - current->flags |= PF_IO_THREAD|PF_LOCAL_THROTTLE|PF_MEMALLOC_NOIO; + current->flags |= PLOOP_PFLAGS; } if (llflush_pios || npios) { /* Now process fsync pios after we have done all other */ npios = process_ploop_fsync_work(ploop, llflush_pios); /* Since dispatcher is single thread no other work can be queued */ if (npios) { - current->flags = old_flags; + current_restore_flags(old_flags, PLOOP_PFLAGS); wait_event_interruptible(ploop->dispatcher_wq_fsync, !atomic_read(&ploop->kt_worker->fsync_pios)); - current->flags |= PF_IO_THREAD|PF_LOCAL_THROTTLE|PF_MEMALLOC_NOIO; + current->flags |= PLOOP_PFLAGS; } } - current->flags = old_flags; + current_restore_flags(old_flags, PLOOP_PFLAGS); } void do_ploop_work(struct work_struct *ws) @@ -2252,7 +2253,7 @@ int ploop_allocator(void *data) if (ploop->prealloc_size) { __set_current_state(TASK_RUNNING); file = ploop_top_delta(ploop)->file; - current->flags |= PF_IO_THREAD|PF_LOCAL_THROTTLE|PF_MEMALLOC_NOIO; + current->flags |= PLOOP_PFLAGS; ret = ploop_preallocate_cluster(ploop, file); if (ret) { /* @@ -2265,7 +2266,7 @@ int ploop_allocator(void *data) ploop_device_name(ploop), ret); } wake_up_interruptible(&ploop->dispatcher_wq_prealloc); - current->flags = old_flags; + current_restore_flags(old_flags, PLOOP_PFLAGS); } if (kthread_should_stop()) { __set_current_state(TASK_RUNNING); @@ -2290,7 +2291,7 @@ int ploop_pio_runner(void *data) int did_process_fsync = 0; for (;;) { - current->flags = old_flags; + current_restore_flags(old_flags, PLOOP_PFLAGS); set_current_state(TASK_INTERRUPTIBLE); check_for_more: @@ -2313,8 +2314,7 @@ int ploop_pio_runner(void *data) continue; } __set_current_state(TASK_RUNNING); - old_flags = current->flags; - current->flags |= PF_IO_THREAD|PF_LOCAL_THROTTLE|PF_MEMALLOC_NOIO; + current->flags |= PLOOP_PFLAGS; llist_for_each_safe(pos, t, llwork) { pio = llist_entry(pos, typeof(*pio), llist); -- 2.43.5 _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel
