Gitweb: http://git.fedorahosted.org/git/?p=lvm2.git;a=commitdiff;h=8a74d1ec79d209aa8... Commit: 8a74d1ec79d209aa8bce51821836179afe7d48f9 Parent: 694c88e031fb44f957c75bea369b898e1dedf932 Author: Zdenek Kabelac zkabelac@redhat.com AuthorDate: Thu Jul 23 11:32:09 2015 +0200 Committer: Zdenek Kabelac zkabelac@redhat.com CommitterDate: Wed Aug 12 14:11:17 2015 +0200
cache: detect smq policy presence
Add code to detect available cache features. Support policy_mq & policy_smq features which might be disabled.
Introduce global_cache_disabled_features_CFG. --- lib/cache_segtype/cache.c | 73 ++++++++++++++++++++++++++++++++++++++++-- lib/config/config_settings.h | 8 ++++ lib/metadata/segtype.h | 3 ++ 3 files changed, 81 insertions(+), 3 deletions(-)
diff --git a/lib/cache_segtype/cache.c b/lib/cache_segtype/cache.c index 18c0168..d74fbf1 100644 --- a/lib/cache_segtype/cache.c +++ b/lib/cache_segtype/cache.c @@ -25,6 +25,11 @@ #include "lv_alloc.h" #include "defaults.h"
+static const char _cache_module[] = "cache"; + +/* TODO: using static field here, maybe should be a part of segment_type */ +static unsigned _feature_mask; + #define SEG_LOG_ERROR(t, p...) \ log_error(t " segment %s of logical volume %s.", ## p, \ dm_config_parent_name(sn), seg->lv->name), 0; @@ -168,9 +173,26 @@ static int _target_present(struct cmd_context *cmd, const struct lv_segment *seg __attribute__((unused)), unsigned *attributes __attribute__((unused))) { - uint32_t maj, min, patchlevel; + /* List of features with their kernel target version */ + static const struct feature { + uint32_t maj; + uint32_t min; + unsigned cache_feature; + const char feature[12]; + const char module[12]; /* check dm-%s */ + } _features[] = { + { 1, 3, CACHE_FEATURE_POLICY_MQ, "policy_mq", "cache-mq" }, + { 1, 8, CACHE_FEATURE_POLICY_SMQ, "policy_smq", "cache-smq" }, + }; + static const char _lvmconf[] = "global/cache_disabled_features"; + static unsigned _attrs = 0; static int _cache_checked = 0; static int _cache_present = 0; + uint32_t maj, min, patchlevel; + unsigned i; + const struct dm_config_node *cn; + const struct dm_config_value *cv; + const char *str;
if (!_cache_checked) { _cache_present = target_present(cmd, "cache", 1); @@ -184,11 +206,53 @@ static int _target_present(struct cmd_context *cmd,
if ((maj < 1) || ((maj == 1) && (min < 3))) { - log_error("The cache kernel module is version %u.%u.%u." - " Version 1.3.0+ is required.", + _cache_present = 0; + log_error("The cache kernel module is version %u.%u.%u. " + "Version 1.3.0+ is required.", maj, min, patchlevel); return 0; } + + + for (i = 0; i < DM_ARRAY_SIZE(_features); ++i) { + if (((maj > _features[i].maj) || + (maj == _features[i].maj && min >= _features[i].min)) && + (!_features[i].module[0] || module_present(cmd, _features[i].module))) + _attrs |= _features[i].cache_feature; + else + log_very_verbose("Target %s does not support %s.", + _cache_module, _features[i].feature); + } + } + + if (attributes) { + if (!_feature_mask) { + /* Support runtime lvm.conf changes, N.B. avoid 32 feature */ + if ((cn = find_config_tree_array(cmd, global_cache_disabled_features_CFG, NULL))) { + for (cv = cn->v; cv; cv = cv->next) { + if (cv->type != DM_CFG_STRING) { + log_error("Ignoring invalid string in config file %s.", + _lvmconf); + continue; + } + str = cv->v.str; + if (!*str) + continue; + for (i = 0; i < DM_ARRAY_SIZE(_features); ++i) + if (strcasecmp(str, _features[i].feature) == 0) + _feature_mask |= _features[i].cache_feature; + } + } + + _feature_mask = ~_feature_mask; + + for (i = 0; i < DM_ARRAY_SIZE(_features); ++i) + if ((_attrs & _features[i].cache_feature) && + !(_feature_mask & _features[i].cache_feature)) + log_very_verbose("Target %s %s support disabled by %s", + _cache_module, _features[i].feature, _lvmconf); + } + *attributes = _attrs & _feature_mask; }
return _cache_present; @@ -376,5 +440,8 @@ int init_cache_segtypes(struct cmd_context *cmd, return_0; log_very_verbose("Initialised segtype: %s", segtype->name);
+ /* Reset mask for recalc */ + _feature_mask = 0; + return 1; } diff --git a/lib/config/config_settings.h b/lib/config/config_settings.h index deb17ef..c8461f7 100644 --- a/lib/config/config_settings.h +++ b/lib/config/config_settings.h @@ -909,6 +909,14 @@ cfg_array(global_thin_disabled_features_CFG, "thin_disabled_features", global_CF "Example:\n" "thin_disabled_features = [ "discards", "block_size" ]\n")
+cfg_array(global_cache_disabled_features_CFG, "cache_disabled_features", global_CFG_SECTION, CFG_ALLOW_EMPTY | CFG_DEFAULT_UNDEFINED, CFG_TYPE_STRING, NULL, vsn(2, 2, 126), NULL, 0, NULL, + "Features to not use in the cache driver.\n" + "This can be helpful for testing, or to avoid\n" + "using a feature that is causing problems.\n" + "Features: policy_mq, policy_smq.\n" + "Example:\n" + "cache_disabled_features = [ "policy_smq" ]\n") + cfg(global_cache_check_executable_CFG, "cache_check_executable", global_CFG_SECTION, CFG_ALLOW_EMPTY | CFG_DEFAULT_COMMENTED, CFG_TYPE_STRING, CACHE_CHECK_CMD, vsn(2, 2, 108), "@CACHE_CHECK_CMD@", 0, NULL, "The full path to the cache_check command.\n" "LVM uses this command to check that a cache metadata\n" diff --git a/lib/metadata/segtype.h b/lib/metadata/segtype.h index 4b2df78..a80d5ed 100644 --- a/lib/metadata/segtype.h +++ b/lib/metadata/segtype.h @@ -191,6 +191,9 @@ int init_thin_segtypes(struct cmd_context *cmd, struct segtype_library *seglib); int init_cache_segtypes(struct cmd_context *cmd, struct segtype_library *seglib); #endif
+#define CACHE_FEATURE_POLICY_MQ (1U << 0) +#define CACHE_FEATURE_POLICY_SMQ (1U << 1) + #define SNAPSHOT_FEATURE_FIXED_LEAK (1U << 0) /* version 1.12 */
#ifdef SNAPSHOT_INTERNAL