ext4: don't use ext4_allocation_contexts for tracing
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@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index ccdfec6..3f62df5 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -3591,8 +3591,7 @@
*/
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);
@@ -3610,11 +3609,6 @@
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)
@@ -3625,16 +3619,9 @@
(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);
+ 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;
}
@@ -3657,29 +3644,19 @@
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);
return 0;
}
@@ -3700,7 +3677,6 @@
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;
@@ -3729,9 +3705,6 @@
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,
@@ -3786,9 +3759,9 @@
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);
@@ -3796,8 +3769,6 @@
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;
@@ -3818,7 +3789,6 @@
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;
@@ -3834,11 +3804,6 @@
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);
@@ -3908,7 +3873,7 @@
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);
@@ -3917,8 +3882,6 @@
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);
}
/*
@@ -4116,14 +4079,10 @@
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],
@@ -4175,15 +4134,13 @@
}
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);
}
/*
@@ -4547,7 +4504,6 @@
{
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;
@@ -4602,12 +4558,6 @@
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);
@@ -4665,12 +4615,7 @@
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);
err = ext4_mb_load_buddy(sb, block_group, &e4b);
if (err)
@@ -4741,7 +4686,5 @@
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 fbdfa3a..b5f4938 100644
--- a/include/trace/events/ext4.h
+++ b/include/trace/events/ext4.h
@@ -396,11 +396,11 @@
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 @@
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_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 )
@@ -779,47 +777,56 @@
);
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),
- TP_ARGS(ac),
+ TP_ARGS(sb, inode, group, start, len),
TP_STRUCT__entry(
__field( dev_t, dev )
__field( ino_t, ino )
- __field( __u32, result_logical )
__field( int, result_start )
__field( __u32, result_group )
__field( int, result_len )
),
TP_fast_assign(
- __entry->dev = ac->ac_sb->s_dev;
- __entry->ino = ac->ac_inode ?
- ac->ac_inode->i_ino : 0;
- __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_start = start;
+ __entry->result_group = group;
+ __entry->result_len = len;
),
- TP_printk("dev %s inode %lu extent %u/%d/%u@%u ",
+ TP_printk("dev %s inode %lu extent %u/%d/%u ",
jbd2_dev_to_name(__entry->dev), (unsigned long) __entry->ino,
__entry->result_group, __entry->result_start,
- __entry->result_len, __entry->result_logical)
+ __entry->result_len)
);
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),
- TP_ARGS(ac)
+ TP_ARGS(sb, inode, group, start, len)
);
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),
- TP_ARGS(ac)
+ TP_ARGS(sb, inode, group, start, len)
);
TRACE_EVENT(ext4_forget,