From: Paul E Luse <paul.e.luse@linux.intel.com>
To: Shushu Yi <teddyxym@outlook.com>
Cc: linux-raid@vger.kernel.org, firnyee@gmail.com, song@kernel.org,
hch@infradead.org, paul.e.luse@intel.com
Subject: Re: [RFC V4] md/raid5: optimize Scattered Address Space and Thread-Level Parallelism to improve RAID5 performance
Date: Tue, 23 Apr 2024 23:48:36 -0700 [thread overview]
Message-ID: <20240423234836.42bfbf39@peluse-desk5> (raw)
In-Reply-To: <SJ0PR10MB5741964ECA25920AD608FEADD8082@SJ0PR10MB5741.namprd10.prod.outlook.com>
Thanks Shushu! Apprecaite the continued follow-ups for sure. Wrt the
performance claims below can you provide the full details on test setup
and results?
Within the next few days I should have a chance to run this again on
latest Xeon with gen5 Samsungs.
-Paul
On Tue, 16 Apr 2024 13:22:53 +0800
Shushu Yi <teddyxym@outlook.com> wrote:
> Optimize scattered address space. Achieves significant improvements in
> both throughput and latency.
>
> Maximize thread-level parallelism and reduce CPU suspension time
> caused by lock contention. Achieve increased overall storage
> throughput by 89.4% and decrease the 99.99th percentile I/O latency
> by 85.4% on a system with four PCIe 4.0 SSDs.
>
> Note: Publish this work as a paper and provide the URL
> (https://www.hotstorage.org/2022/camera-ready/hotstorage22-5/pdf/
> hotstorage22-5.pdf).
>
> Co-developed-by: Yiming Xu <teddyxym@outlook.com>
> Signed-off-by: Yiming Xu <teddyxym@outlook.com>
> Signed-off-by: Shushu Yi <firnyee@gmail.com>
> Tested-by: Paul Luse <paul.e.luse@intel.com>
> ---
> V1 -> V2: Cleaned up coding style and divided into 2 patches (HemiRAID
> and ScalaRAID corresponding to the paper mentioned above). ScalaRAID
> equipped every counter with a counter lock and employ our D-Block.
> HemiRAID increased the number of stripe locks to 128
> V2 -> V3: Adjusted the language used in the subject and changelog.
> Since patch 1/2 in V2 cannot be used independently and does not
> encompass all of our work, it has been merged into a single patch.
> V3 -> V4: Fixed incorrect sending address and changelog format.
>
> drivers/md/md-bitmap.c | 197
> ++++++++++++++++++++++++++++++----------- drivers/md/md-bitmap.h |
> 12 ++- 2 files changed, 154 insertions(+), 55 deletions(-)
>
> diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
> index 059afc24c08b..5ed5fe810b2f 100644
> --- a/drivers/md/md-bitmap.c
> +++ b/drivers/md/md-bitmap.c
> @@ -47,10 +47,12 @@ static inline char *bmname(struct bitmap *bitmap)
> * if we find our page, we increment the page's refcount so that it
> stays
> * allocated while we're using it
> */
> -static int md_bitmap_checkpage(struct bitmap_counts *bitmap,
> - unsigned long page, int create, int
> no_hijack) -__releases(bitmap->lock)
> -__acquires(bitmap->lock)
> +static int md_bitmap_checkpage(struct bitmap_counts *bitmap,
> unsigned long page,
> + int create, int no_hijack, spinlock_t
> *bmclock, int locktype) +__releases(bmclock)
> +__acquires(bmclock)
> +__releases(bitmap->mlock)
> +__acquires(bitmap->mlock)
> {
> unsigned char *mappage;
>
> @@ -65,8 +67,10 @@ __acquires(bitmap->lock)
> return -ENOENT;
>
> /* this page has not been allocated yet */
> -
> - spin_unlock_irq(&bitmap->lock);
> + if (locktype)
> + spin_unlock_irq(bmclock);
> + else
> + write_unlock_irq(&bitmap->mlock);
> /* It is possible that this is being called inside a
> * prepare_to_wait/finish_wait loop from
> raid5c:make_request().
> * In general it is not permitted to sleep in that context
> as it @@ -81,7 +85,11 @@ __acquires(bitmap->lock)
> */
> sched_annotate_sleep();
> mappage = kzalloc(PAGE_SIZE, GFP_NOIO);
> - spin_lock_irq(&bitmap->lock);
> +
> + if (locktype)
> + spin_lock_irq(bmclock);
> + else
> + write_lock_irq(&bitmap->mlock);
>
> if (mappage == NULL) {
> pr_debug("md/bitmap: map page allocation failed,
> hijacking\n"); @@ -399,7 +407,7 @@ static int read_file_page(struct
> file *file, unsigned long index, }
>
> wait_event(bitmap->write_wait,
> - atomic_read(&bitmap->pending_writes)==0);
> + atomic_read(&bitmap->pending_writes) == 0);
> if (test_bit(BITMAP_WRITE_ERROR, &bitmap->flags))
> ret = -EIO;
> out:
> @@ -458,7 +466,7 @@ static void md_bitmap_wait_writes(struct bitmap
> *bitmap) {
> if (bitmap->storage.file)
> wait_event(bitmap->write_wait,
> - atomic_read(&bitmap->pending_writes)==0);
> + atomic_read(&bitmap->pending_writes) ==
> 0); else
> /* Note that we ignore the return value. The writes
> * might have failed, but that would just mean that
> @@ -1248,16 +1256,28 @@ void md_bitmap_write_all(struct bitmap
> *bitmap) static void md_bitmap_count_page(struct bitmap_counts
> *bitmap, sector_t offset, int inc)
> {
> - sector_t chunk = offset >> bitmap->chunkshift;
> - unsigned long page = chunk >> PAGE_COUNTER_SHIFT;
> + sector_t blockno = offset >> (PAGE_SHIFT - SECTOR_SHIFT);
> + sector_t totblocks = bitmap->chunks << (bitmap->chunkshift -
> (PAGE_SHIFT - SECTOR_SHIFT));
> + unsigned long bits = totblocks ? fls((totblocks - 1)) : 0;
> + unsigned long mask = ULONG_MAX << bits | ~(ULONG_MAX <<
> + (bits - (bitmap->chunkshift
> + SECTOR_SHIFT - PAGE_SHIFT)));
> + unsigned long cntid = blockno & mask;
> + unsigned long page = cntid >> PAGE_COUNTER_SHIFT;
> +
> bitmap->bp[page].count += inc;
> md_bitmap_checkfree(bitmap, page);
> }
>
> static void md_bitmap_set_pending(struct bitmap_counts *bitmap,
> sector_t offset) {
> - sector_t chunk = offset >> bitmap->chunkshift;
> - unsigned long page = chunk >> PAGE_COUNTER_SHIFT;
> + sector_t blockno = offset >> (PAGE_SHIFT - SECTOR_SHIFT);
> + sector_t totblocks = bitmap->chunks << (bitmap->chunkshift -
> (PAGE_SHIFT - SECTOR_SHIFT));
> + unsigned long bits = totblocks ? fls((totblocks - 1)) : 0;
> + unsigned long mask = ULONG_MAX << bits | ~(ULONG_MAX <<
> + (bits - (bitmap->chunkshift
> + SECTOR_SHIFT - PAGE_SHIFT)));
> + unsigned long cntid = blockno & mask;
> + unsigned long page = cntid >> PAGE_COUNTER_SHIFT;
> +
> struct bitmap_page *bp = &bitmap->bp[page];
>
> if (!bp->pending)
> @@ -1266,7 +1286,7 @@ static void md_bitmap_set_pending(struct
> bitmap_counts *bitmap, sector_t offset)
> static bitmap_counter_t *md_bitmap_get_counter(struct bitmap_counts
> *bitmap, sector_t offset, sector_t *blocks,
> - int create);
> + int create,
> spinlock_t *bmclock, int locktype);
> static void mddev_set_timeout(struct mddev *mddev, unsigned long
> timeout, bool force)
> @@ -1349,7 +1369,7 @@ void md_bitmap_daemon_work(struct mddev *mddev)
> * decrement and handle accordingly.
> */
> counts = &bitmap->counts;
> - spin_lock_irq(&counts->lock);
> + write_lock_irq(&counts->mlock);
> nextpage = 0;
> for (j = 0; j < counts->chunks; j++) {
> bitmap_counter_t *bmc;
> @@ -1364,7 +1384,7 @@ void md_bitmap_daemon_work(struct mddev *mddev)
> counts->bp[j >> PAGE_COUNTER_SHIFT].pending
> = 0; }
>
> - bmc = md_bitmap_get_counter(counts, block, &blocks,
> 0);
> + bmc = md_bitmap_get_counter(counts, block, &blocks,
> 0, 0, 0); if (!bmc) {
> j |= PAGE_COUNTER_MASK;
> continue;
> @@ -1380,7 +1400,7 @@ void md_bitmap_daemon_work(struct mddev *mddev)
> bitmap->allclean = 0;
> }
> }
> - spin_unlock_irq(&counts->lock);
> + write_unlock_irq(&counts->mlock);
>
> md_bitmap_wait_writes(bitmap);
> /* Now start writeout on any page in NEEDWRITE that isn't
> DIRTY. @@ -1413,17 +1433,25 @@ void md_bitmap_daemon_work(struct
> mddev *mddev)
> static bitmap_counter_t *md_bitmap_get_counter(struct bitmap_counts
> *bitmap, sector_t offset, sector_t *blocks,
> - int create)
> -__releases(bitmap->lock)
> -__acquires(bitmap->lock)
> + int create,
> spinlock_t *bmclock, int locktype) +__releases(bmclock)
> +__acquires(bmclock)
> +__releases(bitmap->mlock)
> +__acquires(bitmap->mlock)
> {
> /* If 'create', we might release the lock and reclaim it.
> * The lock must have been taken with interrupts enabled.
> * If !create, we don't release the lock.
> */
> - sector_t chunk = offset >> bitmap->chunkshift;
> - unsigned long page = chunk >> PAGE_COUNTER_SHIFT;
> - unsigned long pageoff = (chunk & PAGE_COUNTER_MASK) <<
> COUNTER_BYTE_SHIFT;
> + sector_t blockno = offset >> (PAGE_SHIFT - SECTOR_SHIFT);
> + sector_t totblocks = bitmap->chunks << (bitmap->chunkshift -
> (PAGE_SHIFT - SECTOR_SHIFT));
> + unsigned long bits = totblocks ? fls((totblocks - 1)) : 0;
> + unsigned long mask = ULONG_MAX << bits | ~(ULONG_MAX <<
> + (bits - (bitmap->chunkshift
> + SECTOR_SHIFT - PAGE_SHIFT)));
> + unsigned long cntid = blockno & mask;
> + unsigned long page = cntid >> PAGE_COUNTER_SHIFT;
> + unsigned long pageoff = (cntid & PAGE_COUNTER_MASK) <<
> COUNTER_BYTE_SHIFT; +
> sector_t csize;
> int err;
>
> @@ -1435,7 +1463,7 @@ __acquires(bitmap->lock)
> */
> return NULL;
> }
> - err = md_bitmap_checkpage(bitmap, page, create, 0);
> + err = md_bitmap_checkpage(bitmap, page, create, 0, bmclock,
> 1);
> if (bitmap->bp[page].hijacked ||
> bitmap->bp[page].map == NULL)
> @@ -1461,6 +1489,28 @@ __acquires(bitmap->lock)
> &(bitmap->bp[page].map[pageoff]);
> }
>
> +/* set-association */
> +static spinlock_t *md_bitmap_get_bmclock(struct bitmap_counts
> *bitmap, sector_t offset); +
> +static spinlock_t *md_bitmap_get_bmclock(struct bitmap_counts
> *bitmap, sector_t offset) +{
> + sector_t blockno = offset >> (PAGE_SHIFT - SECTOR_SHIFT);
> + sector_t totblocks = bitmap->chunks << (bitmap->chunkshift -
> (PAGE_SHIFT - SECTOR_SHIFT));
> + unsigned long bitscnt = totblocks ? fls((totblocks - 1)) : 0;
> + unsigned long maskcnt = ULONG_MAX << bitscnt | ~(ULONG_MAX
> << (bitscnt -
> + (bitmap->chunkshift +
> SECTOR_SHIFT - PAGE_SHIFT)));
> + unsigned long cntid = blockno & maskcnt;
> +
> + unsigned long totcnts = bitmap->chunks;
> + unsigned long bitslock = totcnts ? fls((totcnts - 1)) : 0;
> + unsigned long masklock = ULONG_MAX << bitslock | ~(ULONG_MAX
> <<
> + (bitslock -
> BITMAP_COUNTER_LOCK_RATIO_SHIFT));
> + unsigned long lockid = cntid & masklock;
> +
> + spinlock_t *bmclock = &(bitmap->bmclocks[lockid]);
> + return bmclock;
> +}
> +
> int md_bitmap_startwrite(struct bitmap *bitmap, sector_t offset,
> unsigned long sectors, int behind) {
> if (!bitmap)
> @@ -1480,11 +1530,15 @@ int md_bitmap_startwrite(struct bitmap
> *bitmap, sector_t offset, unsigned long s while (sectors) {
> sector_t blocks;
> bitmap_counter_t *bmc;
> + spinlock_t *bmclock;
>
> - spin_lock_irq(&bitmap->counts.lock);
> - bmc = md_bitmap_get_counter(&bitmap->counts, offset,
> &blocks, 1);
> + bmclock = md_bitmap_get_bmclock(&bitmap->counts,
> offset);
> + read_lock(&bitmap->counts.mlock);
> + spin_lock_irq(bmclock);
> + bmc = md_bitmap_get_counter(&bitmap->counts, offset,
> &blocks, 1, bmclock, 1); if (!bmc) {
> - spin_unlock_irq(&bitmap->counts.lock);
> + spin_unlock_irq(bmclock);
> + read_unlock(&bitmap->counts.mlock);
> return 0;
> }
>
> @@ -1496,7 +1550,8 @@ int md_bitmap_startwrite(struct bitmap *bitmap,
> sector_t offset, unsigned long s */
> prepare_to_wait(&bitmap->overflow_wait,
> &__wait, TASK_UNINTERRUPTIBLE);
> - spin_unlock_irq(&bitmap->counts.lock);
> + spin_unlock_irq(bmclock);
> + read_unlock(&bitmap->counts.mlock);
> schedule();
> finish_wait(&bitmap->overflow_wait, &__wait);
> continue;
> @@ -1513,7 +1568,8 @@ int md_bitmap_startwrite(struct bitmap *bitmap,
> sector_t offset, unsigned long s
> (*bmc)++;
>
> - spin_unlock_irq(&bitmap->counts.lock);
> + spin_unlock_irq(bmclock);
> + read_unlock(&bitmap->counts.mlock);
>
> offset += blocks;
> if (sectors > blocks)
> @@ -1542,11 +1598,15 @@ void md_bitmap_endwrite(struct bitmap
> *bitmap, sector_t offset, sector_t blocks;
> unsigned long flags;
> bitmap_counter_t *bmc;
> + spinlock_t *bmclock;
>
> - spin_lock_irqsave(&bitmap->counts.lock, flags);
> - bmc = md_bitmap_get_counter(&bitmap->counts, offset,
> &blocks, 0);
> + bmclock = md_bitmap_get_bmclock(&bitmap->counts,
> offset);
> + read_lock(&bitmap->counts.mlock);
> + spin_lock_irqsave(bmclock, flags);
> + bmc = md_bitmap_get_counter(&bitmap->counts, offset,
> &blocks, 0, bmclock, 1); if (!bmc) {
> - spin_unlock_irqrestore(&bitmap->counts.lock,
> flags);
> + spin_unlock_irqrestore(bmclock, flags);
> + read_unlock(&bitmap->counts.mlock);
> return;
> }
>
> @@ -1568,7 +1628,8 @@ void md_bitmap_endwrite(struct bitmap *bitmap,
> sector_t offset, md_bitmap_set_pending(&bitmap->counts, offset);
> bitmap->allclean = 0;
> }
> - spin_unlock_irqrestore(&bitmap->counts.lock, flags);
> + spin_unlock_irqrestore(bmclock, flags);
> + read_unlock(&bitmap->counts.mlock);
> offset += blocks;
> if (sectors > blocks)
> sectors -= blocks;
> @@ -1582,13 +1643,16 @@ static int __bitmap_start_sync(struct bitmap
> *bitmap, sector_t offset, sector_t int degraded)
> {
> bitmap_counter_t *bmc;
> + spinlock_t *bmclock;
> int rv;
> if (bitmap == NULL) {/* FIXME or bitmap set as 'failed' */
> *blocks = 1024;
> return 1; /* always resync if no bitmap */
> }
> - spin_lock_irq(&bitmap->counts.lock);
> - bmc = md_bitmap_get_counter(&bitmap->counts, offset, blocks,
> 0);
> + bmclock = md_bitmap_get_bmclock(&bitmap->counts, offset);
> + read_lock(&bitmap->counts.mlock);
> + spin_lock_irq(bmclock);
> + bmc = md_bitmap_get_counter(&bitmap->counts, offset, blocks,
> 0, bmclock, 1); rv = 0;
> if (bmc) {
> /* locked */
> @@ -1602,7 +1666,8 @@ static int __bitmap_start_sync(struct bitmap
> *bitmap, sector_t offset, sector_t }
> }
> }
> - spin_unlock_irq(&bitmap->counts.lock);
> + spin_unlock_irq(bmclock);
> + read_unlock(&bitmap->counts.mlock);
> return rv;
> }
>
> @@ -1634,13 +1699,16 @@ void md_bitmap_end_sync(struct bitmap
> *bitmap, sector_t offset, sector_t *blocks {
> bitmap_counter_t *bmc;
> unsigned long flags;
> + spinlock_t *bmclock;
>
> if (bitmap == NULL) {
> *blocks = 1024;
> return;
> }
> - spin_lock_irqsave(&bitmap->counts.lock, flags);
> - bmc = md_bitmap_get_counter(&bitmap->counts, offset, blocks,
> 0);
> + bmclock = md_bitmap_get_bmclock(&bitmap->counts, offset);
> + read_lock(&bitmap->counts.mlock);
> + spin_lock_irqsave(bmclock, flags);
> + bmc = md_bitmap_get_counter(&bitmap->counts, offset, blocks,
> 0, bmclock, 1); if (bmc == NULL)
> goto unlock;
> /* locked */
> @@ -1657,7 +1725,8 @@ void md_bitmap_end_sync(struct bitmap *bitmap,
> sector_t offset, sector_t *blocks }
> }
> unlock:
> - spin_unlock_irqrestore(&bitmap->counts.lock, flags);
> + spin_unlock_irqrestore(bmclock, flags);
> + read_unlock(&bitmap->counts.mlock);
> }
> EXPORT_SYMBOL(md_bitmap_end_sync);
>
> @@ -1738,10 +1807,15 @@ static void md_bitmap_set_memory_bits(struct
> bitmap *bitmap, sector_t offset, in
> sector_t secs;
> bitmap_counter_t *bmc;
> - spin_lock_irq(&bitmap->counts.lock);
> - bmc = md_bitmap_get_counter(&bitmap->counts, offset, &secs,
> 1);
> + spinlock_t *bmclock;
> +
> + bmclock = md_bitmap_get_bmclock(&bitmap->counts, offset);
> + read_lock(&bitmap->counts.mlock);
> + spin_lock_irq(bmclock);
> + bmc = md_bitmap_get_counter(&bitmap->counts, offset, &secs,
> 1, bmclock, 1); if (!bmc) {
> - spin_unlock_irq(&bitmap->counts.lock);
> + spin_unlock_irq(bmclock);
> + read_unlock(&bitmap->counts.mlock);
> return;
> }
> if (!*bmc) {
> @@ -1752,7 +1826,8 @@ static void md_bitmap_set_memory_bits(struct
> bitmap *bitmap, sector_t offset, in }
> if (needed)
> *bmc |= NEEDED_MASK;
> - spin_unlock_irq(&bitmap->counts.lock);
> + spin_unlock_irq(bmclock);
> + read_unlock(&bitmap->counts.mlock);
> }
>
> /* dirty the memory and file bits for bitmap chunks "s" to "e" */
> @@ -1806,6 +1881,7 @@ void md_bitmap_free(struct bitmap *bitmap)
> {
> unsigned long k, pages;
> struct bitmap_page *bp;
> + spinlock_t *bmclocks;
>
> if (!bitmap) /* there was no bitmap */
> return;
> @@ -1826,6 +1902,7 @@ void md_bitmap_free(struct bitmap *bitmap)
>
> bp = bitmap->counts.bp;
> pages = bitmap->counts.pages;
> + bmclocks = bitmap->counts.bmclocks;
>
> /* free all allocated memory */
>
> @@ -1834,6 +1911,7 @@ void md_bitmap_free(struct bitmap *bitmap)
> if (bp[k].map && !bp[k].hijacked)
> kfree(bp[k].map);
> kfree(bp);
> + kfree(bmclocks);
> kfree(bitmap);
> }
> EXPORT_SYMBOL(md_bitmap_free);
> @@ -1900,7 +1978,9 @@ struct bitmap *md_bitmap_create(struct mddev
> *mddev, int slot) if (!bitmap)
> return ERR_PTR(-ENOMEM);
>
> - spin_lock_init(&bitmap->counts.lock);
> + /* initialize metadata lock */
> + rwlock_init(&bitmap->counts.mlock);
> +
> atomic_set(&bitmap->pending_writes, 0);
> init_waitqueue_head(&bitmap->write_wait);
> init_waitqueue_head(&bitmap->overflow_wait);
> @@ -2143,6 +2223,8 @@ int md_bitmap_resize(struct bitmap *bitmap,
> sector_t blocks, int ret = 0;
> long pages;
> struct bitmap_page *new_bp;
> + spinlock_t *new_bmclocks;
> + int num_bmclocks, i;
>
> if (bitmap->storage.file && !init) {
> pr_info("md: cannot resize file-based bitmap\n");
> @@ -2211,7 +2293,7 @@ int md_bitmap_resize(struct bitmap *bitmap,
> sector_t blocks, memcpy(page_address(store.sb_page),
> page_address(bitmap->storage.sb_page),
> sizeof(bitmap_super_t));
> - spin_lock_irq(&bitmap->counts.lock);
> + write_lock_irq(&bitmap->counts.mlock);
> md_bitmap_file_unmap(&bitmap->storage);
> bitmap->storage = store;
>
> @@ -2227,18 +2309,28 @@ int md_bitmap_resize(struct bitmap *bitmap,
> sector_t blocks, blocks = min(old_counts.chunks <<
> old_counts.chunkshift, chunks << chunkshift);
>
> + /* initialize bmc locks */
> + num_bmclocks = DIV_ROUND_UP(chunks,
> BITMAP_COUNTER_LOCK_RATIO); +
> + new_bmclocks = kvcalloc(num_bmclocks, sizeof(*new_bmclocks),
> GFP_KERNEL);
> + bitmap->counts.bmclocks = new_bmclocks;
> + for (i = 0; i < num_bmclocks; ++i) {
> + spinlock_t *bmclock = &(bitmap->counts.bmclocks)[i];
> +
> + spin_lock_init(bmclock);
> + }
> +
> /* For cluster raid, need to pre-allocate bitmap */
> if (mddev_is_clustered(bitmap->mddev)) {
> unsigned long page;
> for (page = 0; page < pages; page++) {
> - ret = md_bitmap_checkpage(&bitmap->counts,
> page, 1, 1);
> + ret = md_bitmap_checkpage(&bitmap->counts,
> page, 1, 1, 0, 0); if (ret) {
> unsigned long k;
>
> /* deallocate the page memory */
> - for (k = 0; k < page; k++) {
> + for (k = 0; k < page; k++)
> kfree(new_bp[k].map);
> - }
> kfree(new_bp);
>
> /* restore some fields from
> old_counts */ @@ -2261,11 +2353,12 @@ int md_bitmap_resize(struct
> bitmap *bitmap, sector_t blocks, bitmap_counter_t *bmc_old, *bmc_new;
> int set;
>
> - bmc_old = md_bitmap_get_counter(&old_counts, block,
> &old_blocks, 0);
> + bmc_old = md_bitmap_get_counter(&old_counts, block,
> &old_blocks, 0, 0, 0); set = bmc_old && NEEDED(*bmc_old);
>
> if (set) {
> - bmc_new =
> md_bitmap_get_counter(&bitmap->counts, block, &new_blocks, 1);
> + bmc_new =
> md_bitmap_get_counter(&bitmap->counts, block, &new_blocks,
> +
> 1, 0, 0); if (bmc_new) {
> if (*bmc_new == 0) {
> /* need to set on-disk bits
> too. */ @@ -2301,7 +2394,7 @@ int md_bitmap_resize(struct bitmap
> *bitmap, sector_t blocks, int i;
> while (block < (chunks << chunkshift)) {
> bitmap_counter_t *bmc;
> - bmc = md_bitmap_get_counter(&bitmap->counts,
> block, &new_blocks, 1);
> + bmc = md_bitmap_get_counter(&bitmap->counts,
> block, &new_blocks, 1, 0, 0); if (bmc) {
> /* new space. It needs to be
> resynced, so
> * we set NEEDED_MASK.
> @@ -2317,7 +2410,7 @@ int md_bitmap_resize(struct bitmap *bitmap,
> sector_t blocks, for (i = 0; i < bitmap->storage.file_pages; i++)
> set_page_attr(bitmap, i, BITMAP_PAGE_DIRTY);
> }
> - spin_unlock_irq(&bitmap->counts.lock);
> + write_unlock_irq(&bitmap->counts.mlock);
>
> if (!init) {
> md_bitmap_unplug(bitmap);
> diff --git a/drivers/md/md-bitmap.h b/drivers/md/md-bitmap.h
> index bb9eb418780a..1b9c36bb73ed 100644
> --- a/drivers/md/md-bitmap.h
> +++ b/drivers/md/md-bitmap.h
> @@ -2,7 +2,9 @@
> /*
> * bitmap.h: Copyright (C) Peter T. Breuer (ptb@ot.uc3m.es) 2003
> *
> - * additions: Copyright (C) 2003-2004, Paul Clements, SteelEye
> Technology, Inc.
> + * additions:
> + * Copyright (C) 2003-2004, Paul Clements, SteelEye
> Technology, Inc.
> + * Copyright (C) 2022-2023, Shushu Yi
> (firnyee@gmail.com) */
> #ifndef BITMAP_H
> #define BITMAP_H 1
> @@ -103,6 +105,9 @@ typedef __u16 bitmap_counter_t;
> #define PAGE_COUNTER_MASK (PAGE_COUNTER_RATIO - 1)
>
> #define BITMAP_BLOCK_SHIFT 9
> +/* how many counters share the same bmclock? */
> +#define BITMAP_COUNTER_LOCK_RATIO_SHIFT 0
> +#define BITMAP_COUNTER_LOCK_RATIO (1 <<
> BITMAP_COUNTER_LOCK_RATIO_SHIFT)
> #endif
>
> @@ -116,7 +121,7 @@ typedef __u16 bitmap_counter_t;
> enum bitmap_state {
> BITMAP_STALE = 1, /* the bitmap file is out of
> date or had -EIO */ BITMAP_WRITE_ERROR = 2, /* A write error has
> occurred */
> - BITMAP_HOSTENDIAN =15,
> + BITMAP_HOSTENDIAN = 15,
> };
>
> /* the superblock at the front of the bitmap file -- little endian */
> @@ -180,7 +185,8 @@ struct bitmap_page {
> struct bitmap {
>
> struct bitmap_counts {
> - spinlock_t lock;
> + rwlock_t mlock; /*
> lock for metadata */
> + spinlock_t *bmclocks; /* locks for
> bmc */ struct bitmap_page *bp;
> unsigned long pages; /* total number
> of pages
> * in the bitmap */
next prev parent reply other threads:[~2024-04-25 16:36 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-16 5:22 [RFC V4] md/raid5: optimize Scattered Address Space and Thread-Level Parallelism to improve RAID5 performance Shushu Yi
2024-04-24 6:48 ` Paul E Luse [this message]
2024-04-29 14:23 ` teddyxym
2024-05-01 18:53 ` Paul E Luse
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