ext4: reduce mballoc stack usage with noinline_for_stack
mballoc.c is a whole lot of static functions, which gcc seems to
really like to inline.
With the changes below, on x86, I can at least get from:
432 ext4_mb_new_blocks
240 ext4_mb_free_blocks
208 ext4_mb_discard_group_preallocations
188 ext4_mb_seq_groups_show
164 ext4_mb_init_cache
152 ext4_mb_release_inode_pa
136 ext4_mb_seq_history_show
...
to
220 ext4_mb_free_blocks
188 ext4_mb_seq_groups_show
176 ext4_mb_regular_allocator
164 ext4_mb_init_cache
156 ext4_mb_new_blocks
152 ext4_mb_release_inode_pa
136 ext4_mb_seq_history_show
124 ext4_mb_release_group_pa
...
which still has some big functions in there, but not 432 bytes!
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 9d57695..66e1451 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -1168,8 +1168,9 @@
return err;
}
-static int ext4_mb_load_buddy(struct super_block *sb, ext4_group_t group,
- struct ext4_buddy *e4b)
+static noinline_for_stack int
+ext4_mb_load_buddy(struct super_block *sb, ext4_group_t group,
+ struct ext4_buddy *e4b)
{
struct ext4_sb_info *sbi = EXT4_SB(sb);
struct inode *inode = sbi->s_buddy_cache;
@@ -1965,7 +1966,8 @@
return 0;
}
-static int ext4_mb_regular_allocator(struct ext4_allocation_context *ac)
+static noinline_for_stack int
+ext4_mb_regular_allocator(struct ext4_allocation_context *ac)
{
ext4_group_t group;
ext4_group_t i;
@@ -2465,7 +2467,8 @@
/* if we can't allocate history, then we simple won't use it */
}
-static void ext4_mb_store_history(struct ext4_allocation_context *ac)
+static noinline_for_stack void
+ext4_mb_store_history(struct ext4_allocation_context *ac)
{
struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb);
struct ext4_mb_history h;
@@ -2801,7 +2804,8 @@
return 0;
}
-static void ext4_mb_free_committed_blocks(struct super_block *sb)
+static noinline_for_stack void
+ext4_mb_free_committed_blocks(struct super_block *sb)
{
struct ext4_sb_info *sbi = EXT4_SB(sb);
int err;
@@ -3021,7 +3025,8 @@
* Check quota and mark choosed space (ac->ac_b_ex) non-free in bitmaps
* Returns 0 if success or error code
*/
-static int ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac,
+static noinline_for_stack int
+ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac,
handle_t *handle)
{
struct buffer_head *bitmap_bh = NULL;
@@ -3138,7 +3143,8 @@
* Normalization means making request better in terms of
* size and alignment
*/
-static void ext4_mb_normalize_request(struct ext4_allocation_context *ac,
+static noinline_for_stack void
+ext4_mb_normalize_request(struct ext4_allocation_context *ac,
struct ext4_allocation_request *ar)
{
int bsbits, max;
@@ -3404,7 +3410,8 @@
/*
* search goal blocks in preallocated space
*/
-static int ext4_mb_use_preallocated(struct ext4_allocation_context *ac)
+static noinline_for_stack int
+ext4_mb_use_preallocated(struct ext4_allocation_context *ac)
{
struct ext4_inode_info *ei = EXT4_I(ac->ac_inode);
struct ext4_locality_group *lg;
@@ -3571,7 +3578,8 @@
/*
* creates new preallocated space for given inode
*/
-static int ext4_mb_new_inode_pa(struct ext4_allocation_context *ac)
+static noinline_for_stack int
+ext4_mb_new_inode_pa(struct ext4_allocation_context *ac)
{
struct super_block *sb = ac->ac_sb;
struct ext4_prealloc_space *pa;
@@ -3658,7 +3666,8 @@
/*
* creates new preallocated space for locality group inodes belongs to
*/
-static int ext4_mb_new_group_pa(struct ext4_allocation_context *ac)
+static noinline_for_stack int
+ext4_mb_new_group_pa(struct ext4_allocation_context *ac)
{
struct super_block *sb = ac->ac_sb;
struct ext4_locality_group *lg;
@@ -3731,8 +3740,8 @@
* the caller MUST hold group/inode locks.
* TODO: optimize the case when there are no in-core structures yet
*/
-static int ext4_mb_release_inode_pa(struct ext4_buddy *e4b,
- struct buffer_head *bitmap_bh,
+static noinline_for_stack int
+ext4_mb_release_inode_pa(struct ext4_buddy *e4b, struct buffer_head *bitmap_bh,
struct ext4_prealloc_space *pa)
{
struct ext4_allocation_context *ac;
@@ -3803,7 +3812,8 @@
return err;
}
-static int ext4_mb_release_group_pa(struct ext4_buddy *e4b,
+static noinline_for_stack int
+ext4_mb_release_group_pa(struct ext4_buddy *e4b,
struct ext4_prealloc_space *pa)
{
struct ext4_allocation_context *ac;
@@ -3845,7 +3855,8 @@
* - how many do we discard
* 1) how many requested
*/
-static int ext4_mb_discard_group_preallocations(struct super_block *sb,
+static noinline_for_stack int
+ext4_mb_discard_group_preallocations(struct super_block *sb,
ext4_group_t group, int needed)
{
struct ext4_group_info *grp = ext4_get_group_info(sb, group);
@@ -4167,7 +4178,8 @@
mutex_lock(&ac->ac_lg->lg_mutex);
}
-static int ext4_mb_initialize_context(struct ext4_allocation_context *ac,
+static noinline_for_stack int
+ext4_mb_initialize_context(struct ext4_allocation_context *ac,
struct ext4_allocation_request *ar)
{
struct super_block *sb = ar->inode->i_sb;
@@ -4398,7 +4410,8 @@
ext4_mb_free_committed_blocks(sb);
}
-static int ext4_mb_free_metadata(handle_t *handle, struct ext4_buddy *e4b,
+static noinline_for_stack int
+ext4_mb_free_metadata(handle_t *handle, struct ext4_buddy *e4b,
ext4_group_t group, ext4_grpblk_t block, int count)
{
struct ext4_group_info *db = e4b->bd_info;