From 4e9e63a671fbe13f448fb2e69dfdbb6c2a008368 Mon Sep 17 00:00:00 2001 From: Ryusuke Konishi Date: Fri, 6 Nov 2015 16:31:45 -0800 Subject: [PATCH] nilfs2: do not call nilfs_mdt_bgl_lock() needlessly In the bitmap based allocator implementation, nilfs_mdt_bgl_lock() helper is frequently used to get a spinlock protecting a target block group. This reduces its usage and simplifies arguments of some related functions by directly passing a pointer to the spinlock. Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/nilfs2/alloc.c | 84 ++++++++++++++++++++++------------------------- 1 file changed, 40 insertions(+), 44 deletions(-) diff --git a/fs/nilfs2/alloc.c b/fs/nilfs2/alloc.c index afe983643fdf..ff0d62ce165b 100644 --- a/fs/nilfs2/alloc.c +++ b/fs/nilfs2/alloc.c @@ -133,38 +133,34 @@ nilfs_palloc_bitmap_blkoff(const struct inode *inode, unsigned long group) /** * nilfs_palloc_group_desc_nfrees - get the number of free entries in a group - * @inode: inode of metadata file using this allocator - * @group: group number * @desc: pointer to descriptor structure for the group + * @lock: spin lock protecting @desc */ static unsigned long -nilfs_palloc_group_desc_nfrees(struct inode *inode, unsigned long group, - const struct nilfs_palloc_group_desc *desc) +nilfs_palloc_group_desc_nfrees(const struct nilfs_palloc_group_desc *desc, + spinlock_t *lock) { unsigned long nfree; - spin_lock(nilfs_mdt_bgl_lock(inode, group)); + spin_lock(lock); nfree = le32_to_cpu(desc->pg_nfrees); - spin_unlock(nilfs_mdt_bgl_lock(inode, group)); + spin_unlock(lock); return nfree; } /** * nilfs_palloc_group_desc_add_entries - adjust count of free entries - * @inode: inode of metadata file using this allocator - * @group: group number * @desc: pointer to descriptor structure for the group + * @lock: spin lock protecting @desc * @n: delta to be added */ static void -nilfs_palloc_group_desc_add_entries(struct inode *inode, - unsigned long group, - struct nilfs_palloc_group_desc *desc, - u32 n) +nilfs_palloc_group_desc_add_entries(struct nilfs_palloc_group_desc *desc, + spinlock_t *lock, u32 n) { - spin_lock(nilfs_mdt_bgl_lock(inode, group)); + spin_lock(lock); le32_add_cpu(&desc->pg_nfrees, n); - spin_unlock(nilfs_mdt_bgl_lock(inode, group)); + spin_unlock(lock); } /** @@ -332,17 +328,15 @@ void *nilfs_palloc_block_get_entry(const struct inode *inode, __u64 nr, /** * nilfs_palloc_find_available_slot - find available slot in a group - * @inode: inode of metadata file using this allocator - * @group: group number - * @target: offset number of an entry in the group (start point) * @bitmap: bitmap of the group + * @target: offset number of an entry in the group (start point) * @bsize: size in bits + * @lock: spin lock protecting @bitmap */ -static int nilfs_palloc_find_available_slot(struct inode *inode, - unsigned long group, +static int nilfs_palloc_find_available_slot(unsigned char *bitmap, unsigned long target, - unsigned char *bitmap, - int bsize) + int bsize, + spinlock_t *lock) { int curr, pos, end, i; @@ -351,12 +345,11 @@ static int nilfs_palloc_find_available_slot(struct inode *inode, if (end > bsize) end = bsize; pos = nilfs_find_next_zero_bit(bitmap, end, target); - if (pos < end && - !nilfs_set_bit_atomic( - nilfs_mdt_bgl_lock(inode, group), pos, bitmap)) + if (pos < end && !nilfs_set_bit_atomic(lock, pos, bitmap)) return pos; - } else + } else { end = 0; + } for (i = 0, curr = end; i < bsize; @@ -370,10 +363,8 @@ static int nilfs_palloc_find_available_slot(struct inode *inode, if (end > bsize) end = bsize; pos = nilfs_find_next_zero_bit(bitmap, end, curr); - if ((pos < end) && - !nilfs_set_bit_atomic( - nilfs_mdt_bgl_lock(inode, group), pos, - bitmap)) + if (pos < end && + !nilfs_set_bit_atomic(lock, pos, bitmap)) return pos; } } @@ -477,6 +468,7 @@ int nilfs_palloc_prepare_alloc_entry(struct inode *inode, unsigned long group_offset, maxgroup_offset; unsigned long n, entries_per_group, groups_per_desc_block; unsigned long i, j; + spinlock_t *lock; int pos, ret; ngroups = nilfs_palloc_groups_count(inode); @@ -501,8 +493,8 @@ int nilfs_palloc_prepare_alloc_entry(struct inode *inode, n = nilfs_palloc_rest_groups_in_desc_block(inode, group, maxgroup); for (j = 0; j < n; j++, desc++, group++) { - if (nilfs_palloc_group_desc_nfrees(inode, group, desc) - > 0) { + lock = nilfs_mdt_bgl_lock(inode, group); + if (nilfs_palloc_group_desc_nfrees(desc, lock) > 0) { ret = nilfs_palloc_get_bitmap_block( inode, group, 1, &bitmap_bh); if (ret < 0) @@ -510,12 +502,12 @@ int nilfs_palloc_prepare_alloc_entry(struct inode *inode, bitmap_kaddr = kmap(bitmap_bh->b_page); bitmap = bitmap_kaddr + bh_offset(bitmap_bh); pos = nilfs_palloc_find_available_slot( - inode, group, group_offset, bitmap, - entries_per_group); + bitmap, group_offset, + entries_per_group, lock); if (pos >= 0) { /* found a free entry */ nilfs_palloc_group_desc_add_entries( - inode, group, desc, -1); + desc, lock, -1); req->pr_entry_nr = entries_per_group * group + pos; kunmap(desc_bh->b_page); @@ -573,6 +565,7 @@ void nilfs_palloc_commit_free_entry(struct inode *inode, unsigned long group, group_offset; unsigned char *bitmap; void *desc_kaddr, *bitmap_kaddr; + spinlock_t *lock; group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset); desc_kaddr = kmap(req->pr_desc_bh->b_page); @@ -580,15 +573,15 @@ void nilfs_palloc_commit_free_entry(struct inode *inode, req->pr_desc_bh, desc_kaddr); bitmap_kaddr = kmap(req->pr_bitmap_bh->b_page); bitmap = bitmap_kaddr + bh_offset(req->pr_bitmap_bh); + lock = nilfs_mdt_bgl_lock(inode, group); - if (!nilfs_clear_bit_atomic(nilfs_mdt_bgl_lock(inode, group), - group_offset, bitmap)) + if (!nilfs_clear_bit_atomic(lock, group_offset, bitmap)) nilfs_warning(inode->i_sb, __func__, "entry number %llu already freed: ino=%lu\n", (unsigned long long)req->pr_entry_nr, (unsigned long)inode->i_ino); else - nilfs_palloc_group_desc_add_entries(inode, group, desc, 1); + nilfs_palloc_group_desc_add_entries(desc, lock, 1); kunmap(req->pr_bitmap_bh->b_page); kunmap(req->pr_desc_bh->b_page); @@ -613,6 +606,7 @@ void nilfs_palloc_abort_alloc_entry(struct inode *inode, void *desc_kaddr, *bitmap_kaddr; unsigned char *bitmap; unsigned long group, group_offset; + spinlock_t *lock; group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset); desc_kaddr = kmap(req->pr_desc_bh->b_page); @@ -620,14 +614,15 @@ void nilfs_palloc_abort_alloc_entry(struct inode *inode, req->pr_desc_bh, desc_kaddr); bitmap_kaddr = kmap(req->pr_bitmap_bh->b_page); bitmap = bitmap_kaddr + bh_offset(req->pr_bitmap_bh); - if (!nilfs_clear_bit_atomic(nilfs_mdt_bgl_lock(inode, group), - group_offset, bitmap)) + lock = nilfs_mdt_bgl_lock(inode, group); + + if (!nilfs_clear_bit_atomic(lock, group_offset, bitmap)) nilfs_warning(inode->i_sb, __func__, "entry number %llu already freed: ino=%lu\n", (unsigned long long)req->pr_entry_nr, (unsigned long)inode->i_ino); else - nilfs_palloc_group_desc_add_entries(inode, group, desc, 1); + nilfs_palloc_group_desc_add_entries(desc, lock, 1); kunmap(req->pr_bitmap_bh->b_page); kunmap(req->pr_desc_bh->b_page); @@ -712,6 +707,7 @@ int nilfs_palloc_freev(struct inode *inode, __u64 *entry_nrs, size_t nitems) unsigned char *bitmap; void *desc_kaddr, *bitmap_kaddr; unsigned long group, group_offset; + spinlock_t *lock; int i, j, n, ret; for (i = 0; i < nitems; i = j) { @@ -730,14 +726,14 @@ int nilfs_palloc_freev(struct inode *inode, __u64 *entry_nrs, size_t nitems) inode, group, desc_bh, desc_kaddr); bitmap_kaddr = kmap(bitmap_bh->b_page); bitmap = bitmap_kaddr + bh_offset(bitmap_bh); + lock = nilfs_mdt_bgl_lock(inode, group); for (j = i, n = 0; (j < nitems) && nilfs_palloc_group_is_in(inode, group, entry_nrs[j]); j++) { nilfs_palloc_group(inode, entry_nrs[j], &group_offset); - if (!nilfs_clear_bit_atomic( - nilfs_mdt_bgl_lock(inode, group), - group_offset, bitmap)) { + if (!nilfs_clear_bit_atomic(lock, group_offset, + bitmap)) { nilfs_warning(inode->i_sb, __func__, "entry number %llu already freed: ino=%lu\n", (unsigned long long)entry_nrs[j], @@ -746,7 +742,7 @@ int nilfs_palloc_freev(struct inode *inode, __u64 *entry_nrs, size_t nitems) n++; } } - nilfs_palloc_group_desc_add_entries(inode, group, desc, n); + nilfs_palloc_group_desc_add_entries(desc, lock, n); kunmap(bitmap_bh->b_page); kunmap(desc_bh->b_page); -- GitLab