Many tracepoints were populating an ext4_allocation_context
to pass in, but this requires a slab allocation even when
tracepoints are off. In fact, 4 of 5 of these allocations
were only for tracing. In addition, we were only using a
small fraction of the 144 bytes of this structure for this
purpose.
We can do away with all these alloc/frees of the ac and
simply pass in the bits we care about, instead.
I tested this by turning on tracing and running through
xfstests on x86_64. I did not actually do anything with
the trace output, however.
Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx>
---
Note: This will apply after my other patch,
"[PATCH] fix oops in ext4_mb_release_group_pa tracing"
I could roll them together if desired.
fs/ext4/mballoc.c | 81 ++++++--------------------------------------
include/trace/events/ext4.h | 49 ++++++++++++++++----------
2 files changed, 43 insertions(+), 87 deletions(-)
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 4b4ad4b..f34caf6 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -3535,8 +3535,7 @@ static int ext4_mb_new_preallocation(struct ext4_allocation_context *ac)
*/
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)
+ struct ext4_prealloc_space *pa)
{
struct super_block *sb = e4b->bd_sb;
struct ext4_sb_info *sbi = EXT4_SB(sb);
@@ -3554,11 +3553,6 @@ ext4_mb_release_inode_pa(struct ext4_buddy *e4b, struct buffer_head *bitmap_bh,
BUG_ON(group != e4b->bd_group && pa->pa_len != 0);
end = bit + pa->pa_len;
- if (ac) {
- ac->ac_sb = sb;
- ac->ac_inode = pa->pa_inode;
- }
-
while (bit < end) {
bit = mb_find_next_zero_bit(bitmap_bh->b_data, end, bit);
if (bit >= end)
@@ -3569,16 +3563,9 @@ ext4_mb_release_inode_pa(struct ext4_buddy *e4b, struct buffer_head *bitmap_bh,
(unsigned) next - bit, (unsigned) group);
free += next - bit;
- if (ac) {
- ac->ac_b_ex.fe_group = group;
- ac->ac_b_ex.fe_start = bit;
- ac->ac_b_ex.fe_len = next - bit;
- ac->ac_b_ex.fe_logical = 0;
- trace_ext4_mballoc_discard(ac);
- }
-
- trace_ext4_mb_release_inode_pa(sb, ac, pa, grp_blk_start + bit,
- next - bit);
+ trace_ext4_mballoc_discard(sb, NULL, group, bit, next - bit, 0);
+ trace_ext4_mb_release_inode_pa(sb, pa->pa_inode, pa,
+ grp_blk_start + bit, next - bit);
mb_free_blocks(pa->pa_inode, e4b, bit, next - bit);
bit = next + 1;
}
@@ -3601,29 +3588,19 @@ ext4_mb_release_inode_pa(struct ext4_buddy *e4b, struct buffer_head *bitmap_bh,
static noinline_for_stack int
ext4_mb_release_group_pa(struct ext4_buddy *e4b,
- struct ext4_prealloc_space *pa,
- struct ext4_allocation_context *ac)
+ struct ext4_prealloc_space *pa)
{
struct super_block *sb = e4b->bd_sb;
ext4_group_t group;
ext4_grpblk_t bit;
- trace_ext4_mb_release_group_pa(sb, ac, pa);
+ trace_ext4_mb_release_group_pa(sb, pa);
BUG_ON(pa->pa_deleted == 0);
ext4_get_group_no_and_offset(sb, pa->pa_pstart, &group, &bit);
BUG_ON(group != e4b->bd_group && pa->pa_len != 0);
mb_free_blocks(pa->pa_inode, e4b, bit, pa->pa_len);
atomic_add(pa->pa_len, &EXT4_SB(sb)->s_mb_discarded);
-
- if (ac) {
- ac->ac_sb = sb;
- ac->ac_inode = NULL;
- ac->ac_b_ex.fe_group = group;
- ac->ac_b_ex.fe_start = bit;
- ac->ac_b_ex.fe_len = pa->pa_len;
- ac->ac_b_ex.fe_logical = 0;
- trace_ext4_mballoc_discard(ac);
- }
+ trace_ext4_mballoc_discard(sb, NULL, group, bit, pa->pa_len, 0);
return 0;
}
@@ -3644,7 +3621,6 @@ ext4_mb_discard_group_preallocations(struct super_block *sb,
struct ext4_group_info *grp = ext4_get_group_info(sb, group);
struct buffer_head *bitmap_bh = NULL;
struct ext4_prealloc_space *pa, *tmp;
- struct ext4_allocation_context *ac;
struct list_head list;
struct ext4_buddy e4b;
int err;
@@ -3673,9 +3649,6 @@ ext4_mb_discard_group_preallocations(struct super_block *sb,
needed = EXT4_BLOCKS_PER_GROUP(sb) + 1;
INIT_LIST_HEAD(&list);
- ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS);
- if (ac)
- ac->ac_sb = sb;
repeat:
ext4_lock_group(sb, group);
list_for_each_entry_safe(pa, tmp,
@@ -3730,9 +3703,9 @@ repeat:
spin_unlock(pa->pa_obj_lock);
if (pa->pa_type == MB_GROUP_PA)
- ext4_mb_release_group_pa(&e4b, pa, ac);
+ ext4_mb_release_group_pa(&e4b, pa);
else
- ext4_mb_release_inode_pa(&e4b, bitmap_bh, pa, ac);
+ ext4_mb_release_inode_pa(&e4b, bitmap_bh, pa);
list_del(&pa->u.pa_tmp_list);
call_rcu(&(pa)->u.pa_rcu, ext4_mb_pa_callback);
@@ -3740,8 +3713,6 @@ repeat:
out:
ext4_unlock_group(sb, group);
- if (ac)
- kmem_cache_free(ext4_ac_cachep, ac);
ext4_mb_unload_buddy(&e4b);
put_bh(bitmap_bh);
return free;
@@ -3762,7 +3733,6 @@ void ext4_discard_preallocations(struct inode *inode)
struct super_block *sb = inode->i_sb;
struct buffer_head *bitmap_bh = NULL;
struct ext4_prealloc_space *pa, *tmp;
- struct ext4_allocation_context *ac;
ext4_group_t group = 0;
struct list_head list;
struct ext4_buddy e4b;
@@ -3778,11 +3748,6 @@ void ext4_discard_preallocations(struct inode *inode)
INIT_LIST_HEAD(&list);
- ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS);
- if (ac) {
- ac->ac_sb = sb;
- ac->ac_inode = inode;
- }
repeat:
/* first, collect all pa's in the inode */
spin_lock(&ei->i_prealloc_lock);
@@ -3852,7 +3817,7 @@ repeat:
ext4_lock_group(sb, group);
list_del(&pa->pa_group_list);
- ext4_mb_release_inode_pa(&e4b, bitmap_bh, pa, ac);
+ ext4_mb_release_inode_pa(&e4b, bitmap_bh, pa);
ext4_unlock_group(sb, group);
ext4_mb_unload_buddy(&e4b);
@@ -3861,8 +3826,6 @@ repeat:
list_del(&pa->u.pa_tmp_list);
call_rcu(&(pa)->u.pa_rcu, ext4_mb_pa_callback);
}
- if (ac)
- kmem_cache_free(ext4_ac_cachep, ac);
}
/*
@@ -4060,14 +4023,10 @@ ext4_mb_discard_lg_preallocations(struct super_block *sb,
struct ext4_buddy e4b;
struct list_head discard_list;
struct ext4_prealloc_space *pa, *tmp;
- struct ext4_allocation_context *ac;
mb_debug(1, "discard locality group preallocation\n");
INIT_LIST_HEAD(&discard_list);
- ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS);
- if (ac)
- ac->ac_sb = sb;
spin_lock(&lg->lg_prealloc_lock);
list_for_each_entry_rcu(pa, &lg->lg_prealloc_list[order],
@@ -4119,15 +4078,13 @@ ext4_mb_discard_lg_preallocations(struct super_block *sb,
}
ext4_lock_group(sb, group);
list_del(&pa->pa_group_list);
- ext4_mb_release_group_pa(&e4b, pa, ac);
+ ext4_mb_release_group_pa(&e4b, pa);
ext4_unlock_group(sb, group);
ext4_mb_unload_buddy(&e4b);
list_del(&pa->u.pa_tmp_list);
call_rcu(&(pa)->u.pa_rcu, ext4_mb_pa_callback);
}
- if (ac)
- kmem_cache_free(ext4_ac_cachep, ac);
}
/*
@@ -4491,7 +4448,6 @@ void ext4_free_blocks(handle_t *handle, struct inode *inode,
{
struct buffer_head *bitmap_bh = NULL;
struct super_block *sb = inode->i_sb;
- struct ext4_allocation_context *ac = NULL;
struct ext4_group_desc *gdp;
unsigned long freed = 0;
unsigned int overflow;
@@ -4546,12 +4502,6 @@ void ext4_free_blocks(handle_t *handle, struct inode *inode,
if (!ext4_should_writeback_data(inode))
flags |= EXT4_FREE_BLOCKS_METADATA;
- ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS);
- if (ac) {
- ac->ac_inode = inode;
- ac->ac_sb = sb;
- }
-
do_more:
overflow = 0;
ext4_get_group_no_and_offset(sb, block, &block_group, &bit);
@@ -4609,12 +4559,7 @@ do_more:
BUG_ON(!mb_test_bit(bit + i, bitmap_bh->b_data));
}
#endif
- if (ac) {
- ac->ac_b_ex.fe_group = block_group;
- ac->ac_b_ex.fe_start = bit;
- ac->ac_b_ex.fe_len = count;
- trace_ext4_mballoc_free(ac);
- }
+ trace_ext4_mballoc_free(sb, inode, block_group, bit, count, 0);
err = ext4_mb_load_buddy(sb, block_group, &e4b);
if (err)
@@ -4685,7 +4630,5 @@ error_return:
dquot_free_block(inode, freed);
brelse(bitmap_bh);
ext4_std_error(sb, err);
- if (ac)
- kmem_cache_free(ext4_ac_cachep, ac);
return;
}
diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h
index e352c77..d500fc4 100644
--- a/include/trace/events/ext4.h
+++ b/include/trace/events/ext4.h
@@ -396,11 +396,11 @@ DEFINE_EVENT(ext4__mb_new_pa, ext4_mb_new_group_pa,
TRACE_EVENT(ext4_mb_release_inode_pa,
TP_PROTO(struct super_block *sb,
- struct ext4_allocation_context *ac,
+ struct inode *inode,
struct ext4_prealloc_space *pa,
unsigned long long block, unsigned int count),
- TP_ARGS(sb, ac, pa, block, count),
+ TP_ARGS(sb, inode, pa, block, count),
TP_STRUCT__entry(
__field( dev_t, dev )
@@ -412,8 +412,7 @@ TRACE_EVENT(ext4_mb_release_inode_pa,
TP_fast_assign(
__entry->dev = sb->s_dev;
- __entry->ino = (ac && ac->ac_inode) ?
- ac->ac_inode->i_ino : 0;
+ __entry->ino = inode->i_ino;
__entry->block = block;
__entry->count = count;
),
@@ -425,10 +424,9 @@ TRACE_EVENT(ext4_mb_release_inode_pa,
TRACE_EVENT(ext4_mb_release_group_pa,
TP_PROTO(struct super_block *sb,
- struct ext4_allocation_context *ac,
struct ext4_prealloc_space *pa),
- TP_ARGS(sb, ac, pa),
+ TP_ARGS(sb, pa),
TP_STRUCT__entry(
__field( dev_t, dev )
@@ -779,9 +777,14 @@ TRACE_EVENT(ext4_mballoc_prealloc,
);
DECLARE_EVENT_CLASS(ext4__mballoc,
- TP_PROTO(struct ext4_allocation_context *ac),
+ TP_PROTO(struct super_block *sb,
+ struct inode *inode,
+ ext4_group_t group,
+ ext4_grpblk_t start,
+ ext4_grpblk_t len,
+ ext4_lblk_t logical),
- TP_ARGS(ac),
+ TP_ARGS(sb, inode, group, start, len, logical),
TP_STRUCT__entry(
__field( dev_t, dev )
@@ -793,12 +796,12 @@ DECLARE_EVENT_CLASS(ext4__mballoc,
),
TP_fast_assign(
- __entry->dev = ac->ac_inode->i_sb->s_dev;
- __entry->ino = ac->ac_inode->i_ino;
- __entry->result_logical = ac->ac_b_ex.fe_logical;
- __entry->result_start = ac->ac_b_ex.fe_start;
- __entry->result_group = ac->ac_b_ex.fe_group;
- __entry->result_len = ac->ac_b_ex.fe_len;
+ __entry->dev = sb->s_dev;
+ __entry->ino = inode ? inode->i_ino : 0;
+ __entry->result_logical = logical;
+ __entry->result_start = start;
+ __entry->result_group = group;
+ __entry->result_len = len;
),
TP_printk("dev %s inode %lu extent %u/%d/%u@%u ",
@@ -809,16 +812,26 @@ DECLARE_EVENT_CLASS(ext4__mballoc,
DEFINE_EVENT(ext4__mballoc, ext4_mballoc_discard,
- TP_PROTO(struct ext4_allocation_context *ac),
+ TP_PROTO(struct super_block *sb,
+ struct inode *inode,
+ ext4_group_t group,
+ ext4_grpblk_t start,
+ ext4_grpblk_t len,
+ ext4_lblk_t logical),
- TP_ARGS(ac)
+ TP_ARGS(sb, inode, group, start, len, logical)
);
DEFINE_EVENT(ext4__mballoc, ext4_mballoc_free,
- TP_PROTO(struct ext4_allocation_context *ac),
+ TP_PROTO(struct super_block *sb,
+ struct inode *inode,
+ ext4_group_t group,
+ ext4_grpblk_t start,
+ ext4_grpblk_t len,
+ ext4_lblk_t logical),
- TP_ARGS(ac)
+ TP_ARGS(sb, inode, group, start, len, logical)
);
TRACE_EVENT(ext4_forget,
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
