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Btrfs: add the ability to cache a pointer into the eb
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This cuts down on the CPU time used by map_private_extent_buffer

Signed-off-by: Chris Mason <chris.mason@oracle.com>
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Chris Mason committed Mar 26, 2012
1 parent 0b32f4b commit cfed81a
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Showing 3 changed files with 116 additions and 30 deletions.
80 changes: 57 additions & 23 deletions fs/btrfs/ctree.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -2333,6 +2333,7 @@ static noinline int __push_leaf_right(struct btrfs_trans_handle *trans,
{
struct extent_buffer *left = path->nodes[0];
struct extent_buffer *upper = path->nodes[1];
struct btrfs_map_token token;
struct btrfs_disk_key disk_key;
int slot;
u32 i;
Expand All @@ -2344,6 +2345,8 @@ static noinline int __push_leaf_right(struct btrfs_trans_handle *trans,
u32 data_end;
u32 this_item_size;

btrfs_init_map_token(&token);

if (empty)
nr = 0;
else
Expand Down Expand Up @@ -2421,8 +2424,8 @@ static noinline int __push_leaf_right(struct btrfs_trans_handle *trans,
push_space = BTRFS_LEAF_DATA_SIZE(root);
for (i = 0; i < right_nritems; i++) {
item = btrfs_item_nr(right, i);
push_space -= btrfs_item_size(right, item);
btrfs_set_item_offset(right, item, push_space);
push_space -= btrfs_token_item_size(right, item, &token);
btrfs_set_token_item_offset(right, item, push_space, &token);
}

left_nritems -= push_items;
Expand Down Expand Up @@ -2553,6 +2556,9 @@ static noinline int __push_leaf_left(struct btrfs_trans_handle *trans,
int wret;
u32 this_item_size;
u32 old_left_item_size;
struct btrfs_map_token token;

btrfs_init_map_token(&token);

if (empty)
nr = min(right_nritems, max_slot);
Expand Down Expand Up @@ -2613,9 +2619,10 @@ static noinline int __push_leaf_left(struct btrfs_trans_handle *trans,

item = btrfs_item_nr(left, i);

ioff = btrfs_item_offset(left, item);
btrfs_set_item_offset(left, item,
ioff - (BTRFS_LEAF_DATA_SIZE(root) - old_left_item_size));
ioff = btrfs_token_item_offset(left, item, &token);
btrfs_set_token_item_offset(left, item,
ioff - (BTRFS_LEAF_DATA_SIZE(root) - old_left_item_size),
&token);
}
btrfs_set_header_nritems(left, old_left_nritems + push_items);

Expand Down Expand Up @@ -2645,8 +2652,9 @@ static noinline int __push_leaf_left(struct btrfs_trans_handle *trans,
for (i = 0; i < right_nritems; i++) {
item = btrfs_item_nr(right, i);

push_space = push_space - btrfs_item_size(right, item);
btrfs_set_item_offset(right, item, push_space);
push_space = push_space - btrfs_token_item_size(right,
item, &token);
btrfs_set_token_item_offset(right, item, push_space, &token);
}

btrfs_mark_buffer_dirty(left);
Expand Down Expand Up @@ -2767,6 +2775,9 @@ static noinline int copy_for_split(struct btrfs_trans_handle *trans,
int ret = 0;
int wret;
struct btrfs_disk_key disk_key;
struct btrfs_map_token token;

btrfs_init_map_token(&token);

nritems = nritems - mid;
btrfs_set_header_nritems(right, nritems);
Expand All @@ -2788,8 +2799,9 @@ static noinline int copy_for_split(struct btrfs_trans_handle *trans,
struct btrfs_item *item = btrfs_item_nr(right, i);
u32 ioff;

ioff = btrfs_item_offset(right, item);
btrfs_set_item_offset(right, item, ioff + rt_data_off);
ioff = btrfs_token_item_offset(right, item, &token);
btrfs_set_token_item_offset(right, item,
ioff + rt_data_off, &token);
}

btrfs_set_header_nritems(l, mid);
Expand Down Expand Up @@ -3284,6 +3296,9 @@ int btrfs_truncate_item(struct btrfs_trans_handle *trans,
unsigned int old_size;
unsigned int size_diff;
int i;
struct btrfs_map_token token;

btrfs_init_map_token(&token);

leaf = path->nodes[0];
slot = path->slots[0];
Expand All @@ -3310,8 +3325,9 @@ int btrfs_truncate_item(struct btrfs_trans_handle *trans,
u32 ioff;
item = btrfs_item_nr(leaf, i);

ioff = btrfs_item_offset(leaf, item);
btrfs_set_item_offset(leaf, item, ioff + size_diff);
ioff = btrfs_token_item_offset(leaf, item, &token);
btrfs_set_token_item_offset(leaf, item,
ioff + size_diff, &token);
}

/* shift the data */
Expand Down Expand Up @@ -3381,6 +3397,9 @@ int btrfs_extend_item(struct btrfs_trans_handle *trans,
unsigned int old_data;
unsigned int old_size;
int i;
struct btrfs_map_token token;

btrfs_init_map_token(&token);

leaf = path->nodes[0];

Expand Down Expand Up @@ -3410,8 +3429,9 @@ int btrfs_extend_item(struct btrfs_trans_handle *trans,
u32 ioff;
item = btrfs_item_nr(leaf, i);

ioff = btrfs_item_offset(leaf, item);
btrfs_set_item_offset(leaf, item, ioff - data_size);
ioff = btrfs_token_item_offset(leaf, item, &token);
btrfs_set_token_item_offset(leaf, item,
ioff - data_size, &token);
}

/* shift the data */
Expand Down Expand Up @@ -3454,6 +3474,9 @@ int btrfs_insert_some_items(struct btrfs_trans_handle *trans,
unsigned int data_end;
struct btrfs_disk_key disk_key;
struct btrfs_key found_key;
struct btrfs_map_token token;

btrfs_init_map_token(&token);

for (i = 0; i < nr; i++) {
if (total_size + data_size[i] + sizeof(struct btrfs_item) >
Expand Down Expand Up @@ -3519,8 +3542,9 @@ int btrfs_insert_some_items(struct btrfs_trans_handle *trans,
u32 ioff;

item = btrfs_item_nr(leaf, i);
ioff = btrfs_item_offset(leaf, item);
btrfs_set_item_offset(leaf, item, ioff - total_data);
ioff = btrfs_token_item_offset(leaf, item, &token);
btrfs_set_token_item_offset(leaf, item,
ioff - total_data, &token);
}
/* shift the items */
memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + nr),
Expand All @@ -3547,9 +3571,10 @@ int btrfs_insert_some_items(struct btrfs_trans_handle *trans,
btrfs_cpu_key_to_disk(&disk_key, cpu_key + i);
btrfs_set_item_key(leaf, &disk_key, slot + i);
item = btrfs_item_nr(leaf, slot + i);
btrfs_set_item_offset(leaf, item, data_end - data_size[i]);
btrfs_set_token_item_offset(leaf, item,
data_end - data_size[i], &token);
data_end -= data_size[i];
btrfs_set_item_size(leaf, item, data_size[i]);
btrfs_set_token_item_size(leaf, item, data_size[i], &token);
}
btrfs_set_header_nritems(leaf, nritems + nr);
btrfs_mark_buffer_dirty(leaf);
Expand Down Expand Up @@ -3588,6 +3613,9 @@ int setup_items_for_insert(struct btrfs_trans_handle *trans,
int ret;
struct extent_buffer *leaf;
int slot;
struct btrfs_map_token token;

btrfs_init_map_token(&token);

leaf = path->nodes[0];
slot = path->slots[0];
Expand Down Expand Up @@ -3619,8 +3647,9 @@ int setup_items_for_insert(struct btrfs_trans_handle *trans,
u32 ioff;

item = btrfs_item_nr(leaf, i);
ioff = btrfs_item_offset(leaf, item);
btrfs_set_item_offset(leaf, item, ioff - total_data);
ioff = btrfs_token_item_offset(leaf, item, &token);
btrfs_set_token_item_offset(leaf, item,
ioff - total_data, &token);
}
/* shift the items */
memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + nr),
Expand All @@ -3639,9 +3668,10 @@ int setup_items_for_insert(struct btrfs_trans_handle *trans,
btrfs_cpu_key_to_disk(&disk_key, cpu_key + i);
btrfs_set_item_key(leaf, &disk_key, slot + i);
item = btrfs_item_nr(leaf, slot + i);
btrfs_set_item_offset(leaf, item, data_end - data_size[i]);
btrfs_set_token_item_offset(leaf, item,
data_end - data_size[i], &token);
data_end -= data_size[i];
btrfs_set_item_size(leaf, item, data_size[i]);
btrfs_set_token_item_size(leaf, item, data_size[i], &token);
}

btrfs_set_header_nritems(leaf, nritems + nr);
Expand Down Expand Up @@ -3814,6 +3844,9 @@ int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
int wret;
int i;
u32 nritems;
struct btrfs_map_token token;

btrfs_init_map_token(&token);

leaf = path->nodes[0];
last_off = btrfs_item_offset_nr(leaf, slot + nr - 1);
Expand All @@ -3835,8 +3868,9 @@ int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
u32 ioff;

item = btrfs_item_nr(leaf, i);
ioff = btrfs_item_offset(leaf, item);
btrfs_set_item_offset(leaf, item, ioff + dsize);
ioff = btrfs_token_item_offset(leaf, item, &token);
btrfs_set_token_item_offset(leaf, item,
ioff + dsize, &token);
}

memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot),
Expand Down
13 changes: 13 additions & 0 deletions fs/btrfs/ctree.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1546,6 +1546,17 @@ struct btrfs_ioctl_defrag_range_args {

#define BTRFS_INODE_ROOT_ITEM_INIT (1 << 31)

struct btrfs_map_token {
struct extent_buffer *eb;
char *kaddr;
unsigned long offset;
};

static inline void btrfs_init_map_token (struct btrfs_map_token *token)
{
memset(token, 0, sizeof(*token));
}

/* some macros to generate set/get funcs for the struct fields. This
* assumes there is a lefoo_to_cpu for every type, so lets make a simple
* one for u8:
Expand All @@ -1569,6 +1580,8 @@ struct btrfs_ioctl_defrag_range_args {
#ifndef BTRFS_SETGET_FUNCS
#define BTRFS_SETGET_FUNCS(name, type, member, bits) \
u##bits btrfs_##name(struct extent_buffer *eb, type *s); \
u##bits btrfs_token_##name(struct extent_buffer *eb, type *s, struct btrfs_map_token *token); \
void btrfs_set_token_##name(struct extent_buffer *eb, type *s, u##bits val, struct btrfs_map_token *token);\
void btrfs_set_##name(struct extent_buffer *eb, type *s, u##bits val);
#endif

Expand Down
53 changes: 46 additions & 7 deletions fs/btrfs/struct-funcs.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -44,8 +44,9 @@
#define BTRFS_SETGET_FUNCS(name, type, member, bits) \
u##bits btrfs_##name(struct extent_buffer *eb, type *s); \
void btrfs_set_##name(struct extent_buffer *eb, type *s, u##bits val); \
u##bits btrfs_##name(struct extent_buffer *eb, \
type *s) \
void btrfs_set_token_##name(struct extent_buffer *eb, type *s, u##bits val, struct btrfs_map_token *token); \
u##bits btrfs_token_##name(struct extent_buffer *eb, \
type *s, struct btrfs_map_token *token) \
{ \
unsigned long part_offset = (unsigned long)s; \
unsigned long offset = part_offset + offsetof(type, member); \
Expand All @@ -54,9 +55,18 @@ u##bits btrfs_##name(struct extent_buffer *eb, \
char *kaddr; \
unsigned long map_start; \
unsigned long map_len; \
unsigned long mem_len = sizeof(((type *)0)->member); \
u##bits res; \
if (token && token->kaddr && token->offset <= offset && \
token->eb == eb && \
(token->offset + PAGE_CACHE_SIZE >= offset + mem_len)) { \
kaddr = token->kaddr; \
p = (type *)(kaddr + part_offset - token->offset); \
res = le##bits##_to_cpu(p->member); \
return res; \
} \
err = map_private_extent_buffer(eb, offset, \
sizeof(((type *)0)->member), \
mem_len, \
&kaddr, &map_start, &map_len); \
if (err) { \
__le##bits leres; \
Expand All @@ -65,10 +75,15 @@ u##bits btrfs_##name(struct extent_buffer *eb, \
} \
p = (type *)(kaddr + part_offset - map_start); \
res = le##bits##_to_cpu(p->member); \
if (token) { \
token->kaddr = kaddr; \
token->offset = map_start; \
token->eb = eb; \
} \
return res; \
} \
void btrfs_set_##name(struct extent_buffer *eb, \
type *s, u##bits val) \
void btrfs_set_token_##name(struct extent_buffer *eb, \
type *s, u##bits val, struct btrfs_map_token *token) \
{ \
unsigned long part_offset = (unsigned long)s; \
unsigned long offset = part_offset + offsetof(type, member); \
Expand All @@ -77,8 +92,17 @@ void btrfs_set_##name(struct extent_buffer *eb, \
char *kaddr; \
unsigned long map_start; \
unsigned long map_len; \
unsigned long mem_len = sizeof(((type *)0)->member); \
if (token && token->kaddr && token->offset <= offset && \
token->eb == eb && \
(token->offset + PAGE_CACHE_SIZE >= offset + mem_len)) { \
kaddr = token->kaddr; \
p = (type *)(kaddr + part_offset - token->offset); \
p->member = cpu_to_le##bits(val); \
return; \
} \
err = map_private_extent_buffer(eb, offset, \
sizeof(((type *)0)->member), \
mem_len, \
&kaddr, &map_start, &map_len); \
if (err) { \
__le##bits val2; \
Expand All @@ -88,7 +112,22 @@ void btrfs_set_##name(struct extent_buffer *eb, \
} \
p = (type *)(kaddr + part_offset - map_start); \
p->member = cpu_to_le##bits(val); \
}
if (token) { \
token->kaddr = kaddr; \
token->offset = map_start; \
token->eb = eb; \
} \
} \
void btrfs_set_##name(struct extent_buffer *eb, \
type *s, u##bits val) \
{ \
btrfs_set_token_##name(eb, s, val, NULL); \
} \
u##bits btrfs_##name(struct extent_buffer *eb, \
type *s) \
{ \
return btrfs_token_##name(eb, s, NULL); \
} \

#include "ctree.h"

Expand Down

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