From 7e5fec31685a5c69b81e9005eaed44318880d881 Mon Sep 17 00:00:00 2001 From: Fabian Frederick Date: Tue, 14 Jun 2016 00:26:35 +0200 Subject: drbd: code cleanups without semantic changes This contains various cosmetic fixes ranging from simple typos to const-ifying, and using booleans properly. Original commit messages from Fabian's patch set: drbd: debugfs: constify drbd_version_fops drbd: use seq_put instead of seq_print where possible drbd: include linux/uaccess.h instead of asm/uaccess.h drbd: use const char * const for drbd strings drbd: kerneldoc warning fix in w_e_end_data_req() drbd: use unsigned for one bit fields drbd: use bool for peer is_ states drbd: fix typo drbd: use | for bitmask combination drbd: use true/false for bool drbd: fix drbd_bm_init() comments drbd: introduce peer state union drbd: fix maybe_pull_ahead() locking comments drbd: use bool for growing drbd: remove redundant declarations drbd: replace if/BUG by BUG_ON Signed-off-by: Fabian Frederick Signed-off-by: Roland Kammerer Signed-off-by: Jens Axboe --- drivers/block/drbd/drbd_bitmap.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/block/drbd/drbd_bitmap.c') diff --git a/drivers/block/drbd/drbd_bitmap.c b/drivers/block/drbd/drbd_bitmap.c index e5d89f623b90..095625beaf98 100644 --- a/drivers/block/drbd/drbd_bitmap.c +++ b/drivers/block/drbd/drbd_bitmap.c @@ -427,8 +427,7 @@ static struct page **bm_realloc_pages(struct drbd_bitmap *b, unsigned long want) } /* - * called on driver init only. TODO call when a device is created. - * allocates the drbd_bitmap, and stores it in device->bitmap. + * allocates the drbd_bitmap and stores it in device->bitmap. */ int drbd_bm_init(struct drbd_device *device) { @@ -633,7 +632,8 @@ int drbd_bm_resize(struct drbd_device *device, sector_t capacity, int set_new_bi unsigned long bits, words, owords, obits; unsigned long want, have, onpages; /* number of pages */ struct page **npages, **opages = NULL; - int err = 0, growing; + int err = 0; + bool growing; if (!expect(b)) return -ENOMEM; -- cgit v1.2.3 From 13c2088d41e9c63e1a484a08a1d250ff74b299b5 Mon Sep 17 00:00:00 2001 From: Lars Ellenberg Date: Tue, 14 Jun 2016 00:26:37 +0200 Subject: drbd: finally report ms, not jiffies, in log message Also skip the message unless bitmap IO took longer than 5 ms. Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg Signed-off-by: Jens Axboe --- drivers/block/drbd/drbd_bitmap.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'drivers/block/drbd/drbd_bitmap.c') diff --git a/drivers/block/drbd/drbd_bitmap.c b/drivers/block/drbd/drbd_bitmap.c index 095625beaf98..0807fcbf863d 100644 --- a/drivers/block/drbd/drbd_bitmap.c +++ b/drivers/block/drbd/drbd_bitmap.c @@ -1121,10 +1121,14 @@ static int bm_rw(struct drbd_device *device, const unsigned int flags, unsigned kref_put(&ctx->kref, &drbd_bm_aio_ctx_destroy); /* summary for global bitmap IO */ - if (flags == 0) - drbd_info(device, "bitmap %s of %u pages took %lu jiffies\n", - (flags & BM_AIO_READ) ? "READ" : "WRITE", - count, jiffies - now); + if (flags == 0) { + unsigned int ms = jiffies_to_msecs(jiffies - now); + if (ms > 5) { + drbd_info(device, "bitmap %s of %u pages took %u ms\n", + (flags & BM_AIO_READ) ? "READ" : "WRITE", + count, ms); + } + } if (ctx->error) { drbd_alert(device, "we had at least one MD IO ERROR during bitmap IO\n"); -- cgit v1.2.3 From 27ea1d876e16c0ca5ae6335fc85cf4f278f5c98c Mon Sep 17 00:00:00 2001 From: Lars Ellenberg Date: Tue, 14 Jun 2016 00:26:38 +0200 Subject: drbd: al_write_transaction: skip re-scanning of bitmap page pointer array For larger devices, the array of bitmap page pointers can grow very large (8000 pointers per TB of storage). For each activity log transaction, we need to flush the associated bitmap pages to stable storage. Currently, we just "mark" the respective pages while setting up the transaction, then tell the bitmap code to write out all marked pages, but skip unchanged pages. But one such transaction can affect only a small number of bitmap pages, there is no need to scan the full array of several (ten-)thousand page pointers to find the few marked ones. Instead, remember the index numbers of the few affected pages, and later only re-check those to skip duplicates and unchanged ones. Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg Signed-off-by: Jens Axboe --- drivers/block/drbd/drbd_actlog.c | 2 ++ drivers/block/drbd/drbd_bitmap.c | 66 +++++++++++++++++++++++++++++++--------- drivers/block/drbd/drbd_int.h | 1 + 3 files changed, 54 insertions(+), 15 deletions(-) (limited to 'drivers/block/drbd/drbd_bitmap.c') diff --git a/drivers/block/drbd/drbd_actlog.c b/drivers/block/drbd/drbd_actlog.c index f9af555f9e69..0a1aaf8c24c4 100644 --- a/drivers/block/drbd/drbd_actlog.c +++ b/drivers/block/drbd/drbd_actlog.c @@ -341,6 +341,8 @@ static int __al_write_transaction(struct drbd_device *device, struct al_transact i = 0; + drbd_bm_reset_al_hints(device); + /* Even though no one can start to change this list * once we set the LC_LOCKED -- from drbd_al_begin_io(), * lc_try_lock_for_transaction() --, someone may still diff --git a/drivers/block/drbd/drbd_bitmap.c b/drivers/block/drbd/drbd_bitmap.c index 0807fcbf863d..ab62b81c2ca7 100644 --- a/drivers/block/drbd/drbd_bitmap.c +++ b/drivers/block/drbd/drbd_bitmap.c @@ -96,6 +96,13 @@ struct drbd_bitmap { struct page **bm_pages; spinlock_t bm_lock; + /* exclusively to be used by __al_write_transaction(), + * drbd_bm_mark_for_writeout() and + * and drbd_bm_write_hinted() -> bm_rw() called from there. + */ + unsigned int n_bitmap_hints; + unsigned int al_bitmap_hints[AL_UPDATES_PER_TRANSACTION]; + /* see LIMITATIONS: above */ unsigned long bm_set; /* nr of set bits; THINK maybe atomic_t? */ @@ -242,6 +249,11 @@ static void bm_set_page_need_writeout(struct page *page) set_bit(BM_PAGE_NEED_WRITEOUT, &page_private(page)); } +void drbd_bm_reset_al_hints(struct drbd_device *device) +{ + device->bitmap->n_bitmap_hints = 0; +} + /** * drbd_bm_mark_for_writeout() - mark a page with a "hint" to be considered for writeout * @device: DRBD device. @@ -253,6 +265,7 @@ static void bm_set_page_need_writeout(struct page *page) */ void drbd_bm_mark_for_writeout(struct drbd_device *device, int page_nr) { + struct drbd_bitmap *b = device->bitmap; struct page *page; if (page_nr >= device->bitmap->bm_number_of_pages) { drbd_warn(device, "BAD: page_nr: %u, number_of_pages: %u\n", @@ -260,7 +273,9 @@ void drbd_bm_mark_for_writeout(struct drbd_device *device, int page_nr) return; } page = device->bitmap->bm_pages[page_nr]; - set_bit(BM_PAGE_HINT_WRITEOUT, &page_private(page)); + BUG_ON(b->n_bitmap_hints >= ARRAY_SIZE(b->al_bitmap_hints)); + if (!test_and_set_bit(BM_PAGE_HINT_WRITEOUT, &page_private(page))) + b->al_bitmap_hints[b->n_bitmap_hints++] = page_nr; } static int bm_test_page_unchanged(struct page *page) @@ -1030,7 +1045,7 @@ static int bm_rw(struct drbd_device *device, const unsigned int flags, unsigned { struct drbd_bm_aio_ctx *ctx; struct drbd_bitmap *b = device->bitmap; - int num_pages, i, count = 0; + unsigned int num_pages, i, count = 0; unsigned long now; char ppb[10]; int err = 0; @@ -1078,16 +1093,37 @@ static int bm_rw(struct drbd_device *device, const unsigned int flags, unsigned now = jiffies; /* let the layers below us try to merge these bios... */ - for (i = 0; i < num_pages; i++) { - /* ignore completely unchanged pages */ - if (lazy_writeout_upper_idx && i == lazy_writeout_upper_idx) - break; - if (!(flags & BM_AIO_READ)) { - if ((flags & BM_AIO_WRITE_HINTED) && - !test_and_clear_bit(BM_PAGE_HINT_WRITEOUT, - &page_private(b->bm_pages[i]))) - continue; + if (flags & BM_AIO_READ) { + for (i = 0; i < num_pages; i++) { + atomic_inc(&ctx->in_flight); + bm_page_io_async(ctx, i); + ++count; + cond_resched(); + } + } else if (flags & BM_AIO_WRITE_HINTED) { + /* ASSERT: BM_AIO_WRITE_ALL_PAGES is not set. */ + unsigned int hint; + for (hint = 0; hint < b->n_bitmap_hints; hint++) { + i = b->al_bitmap_hints[hint]; + if (i >= num_pages) /* == -1U: no hint here. */ + continue; + /* Several AL-extents may point to the same page. */ + if (!test_and_clear_bit(BM_PAGE_HINT_WRITEOUT, + &page_private(b->bm_pages[i]))) + continue; + /* Has it even changed? */ + if (bm_test_page_unchanged(b->bm_pages[i])) + continue; + atomic_inc(&ctx->in_flight); + bm_page_io_async(ctx, i); + ++count; + } + } else { + for (i = 0; i < num_pages; i++) { + /* ignore completely unchanged pages */ + if (lazy_writeout_upper_idx && i == lazy_writeout_upper_idx) + break; if (!(flags & BM_AIO_WRITE_ALL_PAGES) && bm_test_page_unchanged(b->bm_pages[i])) { dynamic_drbd_dbg(device, "skipped bm write for idx %u\n", i); @@ -1100,11 +1136,11 @@ static int bm_rw(struct drbd_device *device, const unsigned int flags, unsigned dynamic_drbd_dbg(device, "skipped bm lazy write for idx %u\n", i); continue; } + atomic_inc(&ctx->in_flight); + bm_page_io_async(ctx, i); + ++count; + cond_resched(); } - atomic_inc(&ctx->in_flight); - bm_page_io_async(ctx, i); - ++count; - cond_resched(); } /* diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h index 2c9194dc2ec2..352fbe031b98 100644 --- a/drivers/block/drbd/drbd_int.h +++ b/drivers/block/drbd/drbd_int.h @@ -1378,6 +1378,7 @@ extern int drbd_bm_e_weight(struct drbd_device *device, unsigned long enr); extern int drbd_bm_read(struct drbd_device *device) __must_hold(local); extern void drbd_bm_mark_for_writeout(struct drbd_device *device, int page_nr); extern int drbd_bm_write(struct drbd_device *device) __must_hold(local); +extern void drbd_bm_reset_al_hints(struct drbd_device *device) __must_hold(local); extern int drbd_bm_write_hinted(struct drbd_device *device) __must_hold(local); extern int drbd_bm_write_lazy(struct drbd_device *device, unsigned upper_idx) __must_hold(local); extern int drbd_bm_write_all(struct drbd_device *device) __must_hold(local); -- cgit v1.2.3