diff options
author | Joe Thornber <ejt@redhat.com> | 2016-09-20 12:16:00 +0200 |
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committer | Mike Snitzer <snitzer@redhat.com> | 2016-09-22 17:15:05 +0200 |
commit | f177940a80917044f0ea6fd18ea1bfbdff012050 (patch) | |
tree | fc1a276c90fcb1b77eb302fa35808616d127e7a2 /drivers/md | |
parent | dm array: introduce cursor api (diff) | |
download | linux-f177940a80917044f0ea6fd18ea1bfbdff012050.tar.xz linux-f177940a80917044f0ea6fd18ea1bfbdff012050.zip |
dm cache metadata: switch to using the new cursor api for loading metadata
This change offers a pretty significant performance improvement.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'drivers/md')
-rw-r--r-- | drivers/md/dm-cache-metadata.c | 103 |
1 files changed, 80 insertions, 23 deletions
diff --git a/drivers/md/dm-cache-metadata.c b/drivers/md/dm-cache-metadata.c index a60f10a0ee0a..695577812cf6 100644 --- a/drivers/md/dm-cache-metadata.c +++ b/drivers/md/dm-cache-metadata.c @@ -140,6 +140,13 @@ struct dm_cache_metadata { * the device. */ bool fail_io:1; + + /* + * These structures are used when loading metadata. They're too + * big to put on the stack. + */ + struct dm_array_cursor mapping_cursor; + struct dm_array_cursor hint_cursor; }; /*------------------------------------------------------------------- @@ -1171,31 +1178,37 @@ static bool hints_array_available(struct dm_cache_metadata *cmd, hints_array_initialized(cmd); } -static int __load_mapping(void *context, uint64_t cblock, void *leaf) +static int __load_mapping(struct dm_cache_metadata *cmd, + uint64_t cb, bool hints_valid, + struct dm_array_cursor *mapping_cursor, + struct dm_array_cursor *hint_cursor, + load_mapping_fn fn, void *context) { int r = 0; - bool dirty; - __le64 value; - __le32 hint_value = 0; + + __le64 mapping; + __le32 hint = 0; + + __le64 *mapping_value_le; + __le32 *hint_value_le; + dm_oblock_t oblock; unsigned flags; - struct thunk *thunk = context; - struct dm_cache_metadata *cmd = thunk->cmd; - memcpy(&value, leaf, sizeof(value)); - unpack_value(value, &oblock, &flags); + dm_array_cursor_get_value(mapping_cursor, (void **) &mapping_value_le); + memcpy(&mapping, mapping_value_le, sizeof(mapping)); + unpack_value(mapping, &oblock, &flags); if (flags & M_VALID) { - if (thunk->hints_valid) { - r = dm_array_get_value(&cmd->hint_info, cmd->hint_root, - cblock, &hint_value); - if (r && r != -ENODATA) - return r; + if (hints_valid) { + dm_array_cursor_get_value(hint_cursor, (void **) &hint_value_le); + memcpy(&hint, hint_value_le, sizeof(hint)); } - dirty = thunk->respect_dirty_flags ? (flags & M_DIRTY) : true; - r = thunk->fn(thunk->context, oblock, to_cblock(cblock), - dirty, le32_to_cpu(hint_value), thunk->hints_valid); + r = fn(context, oblock, to_cblock(cb), flags & M_DIRTY, + le32_to_cpu(hint), hints_valid); + if (r) + DMERR("policy couldn't load cblock"); } return r; @@ -1205,16 +1218,60 @@ static int __load_mappings(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy, load_mapping_fn fn, void *context) { - struct thunk thunk; + int r; + uint64_t cb; - thunk.fn = fn; - thunk.context = context; + bool hints_valid = hints_array_available(cmd, policy); - thunk.cmd = cmd; - thunk.respect_dirty_flags = cmd->clean_when_opened; - thunk.hints_valid = hints_array_available(cmd, policy); + if (from_cblock(cmd->cache_blocks) == 0) + /* Nothing to do */ + return 0; - return dm_array_walk(&cmd->info, cmd->root, __load_mapping, &thunk); + r = dm_array_cursor_begin(&cmd->info, cmd->root, &cmd->mapping_cursor); + if (r) + return r; + + if (hints_valid) { + r = dm_array_cursor_begin(&cmd->hint_info, cmd->hint_root, &cmd->hint_cursor); + if (r) { + dm_array_cursor_end(&cmd->mapping_cursor); + return r; + } + } + + for (cb = 0; ; cb++) { + r = __load_mapping(cmd, cb, hints_valid, + &cmd->mapping_cursor, &cmd->hint_cursor, + fn, context); + if (r) + goto out; + + /* + * We need to break out before we move the cursors. + */ + if (cb >= (from_cblock(cmd->cache_blocks) - 1)) + break; + + r = dm_array_cursor_next(&cmd->mapping_cursor); + if (r) { + DMERR("dm_array_cursor_next for mapping failed"); + goto out; + } + + if (hints_valid) { + r = dm_array_cursor_next(&cmd->hint_cursor); + if (r) { + DMERR("dm_array_cursor_next for hint failed"); + goto out; + } + } + } +out: + dm_array_cursor_end(&cmd->mapping_cursor); + if (hints_valid) + dm_array_cursor_end(&cmd->hint_cursor); + + return r; } int dm_cache_load_mappings(struct dm_cache_metadata *cmd, |