diff options
| author | Chris Mason <chris.mason@oracle.com> | 2012-03-03 07:40:03 -0500 |
|---|---|---|
| committer | Chris Mason <chris.mason@oracle.com> | 2012-03-26 17:04:23 -0400 |
| commit | cfed81a04eb555f5606d1b6a54bdbabab0ee1ac3 (patch) | |
| tree | 2a763276869693b21c0e3a14f725f642c1f27fd3 /fs/btrfs/struct-funcs.c | |
| parent | 0b32f4bbb423f02acee6d43cd442f5f0775db7e0 (diff) | |
Btrfs: add the ability to cache a pointer into the eb
This cuts down on the CPU time used by map_private_extent_buffer
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs/btrfs/struct-funcs.c')
| -rw-r--r-- | fs/btrfs/struct-funcs.c | 53 |
1 files changed, 46 insertions, 7 deletions
diff --git a/fs/btrfs/struct-funcs.c b/fs/btrfs/struct-funcs.c index bc1f6ad18442..c6ffa5812419 100644 --- a/fs/btrfs/struct-funcs.c +++ b/fs/btrfs/struct-funcs.c | |||
| @@ -44,8 +44,9 @@ | |||
| 44 | #define BTRFS_SETGET_FUNCS(name, type, member, bits) \ | 44 | #define BTRFS_SETGET_FUNCS(name, type, member, bits) \ |
| 45 | u##bits btrfs_##name(struct extent_buffer *eb, type *s); \ | 45 | u##bits btrfs_##name(struct extent_buffer *eb, type *s); \ |
| 46 | void btrfs_set_##name(struct extent_buffer *eb, type *s, u##bits val); \ | 46 | void btrfs_set_##name(struct extent_buffer *eb, type *s, u##bits val); \ |
| 47 | u##bits btrfs_##name(struct extent_buffer *eb, \ | 47 | void btrfs_set_token_##name(struct extent_buffer *eb, type *s, u##bits val, struct btrfs_map_token *token); \ |
| 48 | type *s) \ | 48 | u##bits btrfs_token_##name(struct extent_buffer *eb, \ |
| 49 | type *s, struct btrfs_map_token *token) \ | ||
| 49 | { \ | 50 | { \ |
| 50 | unsigned long part_offset = (unsigned long)s; \ | 51 | unsigned long part_offset = (unsigned long)s; \ |
| 51 | unsigned long offset = part_offset + offsetof(type, member); \ | 52 | unsigned long offset = part_offset + offsetof(type, member); \ |
| @@ -54,9 +55,18 @@ u##bits btrfs_##name(struct extent_buffer *eb, \ | |||
| 54 | char *kaddr; \ | 55 | char *kaddr; \ |
| 55 | unsigned long map_start; \ | 56 | unsigned long map_start; \ |
| 56 | unsigned long map_len; \ | 57 | unsigned long map_len; \ |
| 58 | unsigned long mem_len = sizeof(((type *)0)->member); \ | ||
| 57 | u##bits res; \ | 59 | u##bits res; \ |
| 60 | if (token && token->kaddr && token->offset <= offset && \ | ||
| 61 | token->eb == eb && \ | ||
| 62 | (token->offset + PAGE_CACHE_SIZE >= offset + mem_len)) { \ | ||
| 63 | kaddr = token->kaddr; \ | ||
| 64 | p = (type *)(kaddr + part_offset - token->offset); \ | ||
| 65 | res = le##bits##_to_cpu(p->member); \ | ||
| 66 | return res; \ | ||
| 67 | } \ | ||
| 58 | err = map_private_extent_buffer(eb, offset, \ | 68 | err = map_private_extent_buffer(eb, offset, \ |
| 59 | sizeof(((type *)0)->member), \ | 69 | mem_len, \ |
| 60 | &kaddr, &map_start, &map_len); \ | 70 | &kaddr, &map_start, &map_len); \ |
| 61 | if (err) { \ | 71 | if (err) { \ |
| 62 | __le##bits leres; \ | 72 | __le##bits leres; \ |
| @@ -65,10 +75,15 @@ u##bits btrfs_##name(struct extent_buffer *eb, \ | |||
| 65 | } \ | 75 | } \ |
| 66 | p = (type *)(kaddr + part_offset - map_start); \ | 76 | p = (type *)(kaddr + part_offset - map_start); \ |
| 67 | res = le##bits##_to_cpu(p->member); \ | 77 | res = le##bits##_to_cpu(p->member); \ |
| 78 | if (token) { \ | ||
| 79 | token->kaddr = kaddr; \ | ||
| 80 | token->offset = map_start; \ | ||
| 81 | token->eb = eb; \ | ||
| 82 | } \ | ||
| 68 | return res; \ | 83 | return res; \ |
| 69 | } \ | 84 | } \ |
| 70 | void btrfs_set_##name(struct extent_buffer *eb, \ | 85 | void btrfs_set_token_##name(struct extent_buffer *eb, \ |
| 71 | type *s, u##bits val) \ | 86 | type *s, u##bits val, struct btrfs_map_token *token) \ |
| 72 | { \ | 87 | { \ |
| 73 | unsigned long part_offset = (unsigned long)s; \ | 88 | unsigned long part_offset = (unsigned long)s; \ |
| 74 | unsigned long offset = part_offset + offsetof(type, member); \ | 89 | unsigned long offset = part_offset + offsetof(type, member); \ |
| @@ -77,8 +92,17 @@ void btrfs_set_##name(struct extent_buffer *eb, \ | |||
| 77 | char *kaddr; \ | 92 | char *kaddr; \ |
| 78 | unsigned long map_start; \ | 93 | unsigned long map_start; \ |
| 79 | unsigned long map_len; \ | 94 | unsigned long map_len; \ |
| 95 | unsigned long mem_len = sizeof(((type *)0)->member); \ | ||
| 96 | if (token && token->kaddr && token->offset <= offset && \ | ||
| 97 | token->eb == eb && \ | ||
| 98 | (token->offset + PAGE_CACHE_SIZE >= offset + mem_len)) { \ | ||
| 99 | kaddr = token->kaddr; \ | ||
| 100 | p = (type *)(kaddr + part_offset - token->offset); \ | ||
| 101 | p->member = cpu_to_le##bits(val); \ | ||
| 102 | return; \ | ||
| 103 | } \ | ||
| 80 | err = map_private_extent_buffer(eb, offset, \ | 104 | err = map_private_extent_buffer(eb, offset, \ |
| 81 | sizeof(((type *)0)->member), \ | 105 | mem_len, \ |
| 82 | &kaddr, &map_start, &map_len); \ | 106 | &kaddr, &map_start, &map_len); \ |
| 83 | if (err) { \ | 107 | if (err) { \ |
| 84 | __le##bits val2; \ | 108 | __le##bits val2; \ |
| @@ -88,7 +112,22 @@ void btrfs_set_##name(struct extent_buffer *eb, \ | |||
| 88 | } \ | 112 | } \ |
| 89 | p = (type *)(kaddr + part_offset - map_start); \ | 113 | p = (type *)(kaddr + part_offset - map_start); \ |
| 90 | p->member = cpu_to_le##bits(val); \ | 114 | p->member = cpu_to_le##bits(val); \ |
| 91 | } | 115 | if (token) { \ |
| 116 | token->kaddr = kaddr; \ | ||
| 117 | token->offset = map_start; \ | ||
| 118 | token->eb = eb; \ | ||
| 119 | } \ | ||
| 120 | } \ | ||
| 121 | void btrfs_set_##name(struct extent_buffer *eb, \ | ||
| 122 | type *s, u##bits val) \ | ||
| 123 | { \ | ||
| 124 | btrfs_set_token_##name(eb, s, val, NULL); \ | ||
| 125 | } \ | ||
| 126 | u##bits btrfs_##name(struct extent_buffer *eb, \ | ||
| 127 | type *s) \ | ||
| 128 | { \ | ||
| 129 | return btrfs_token_##name(eb, s, NULL); \ | ||
| 130 | } \ | ||
| 92 | 131 | ||
| 93 | #include "ctree.h" | 132 | #include "ctree.h" |
| 94 | 133 | ||