11:50 a.m.
Gitweb:
http://git.fedorahosted.org/git/?p=lvm2.git;a=commitdiff;h=f25132b354b110...
Commit: f25132b354b110994b9da8dc3edf39cf4db37657
Parent: 1dfedcc179b6f7caee1069974ab34ddd111ef01d
Author: David Teigland <teigland(a)redhat.com>
AuthorDate: Wed May 6 14:49:44 2015 -0500
Committer: David Teigland <teigland(a)redhat.com>
CommitterDate: Fri May 8 11:44:49 2015 -0500
lvmcache: choose preferred device once
Once the preferred duplicate devices have been set in
lvmcache, don't attempt to pick preferred duplicates
again.
---
lib/cache/lvmcache.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++++-
lib/cache/lvmcache.h | 2 +
lib/cache/lvmetad.c | 19 ++++++++-------
3 files changed, 68 insertions(+), 11 deletions(-)
diff --git a/lib/cache/lvmcache.c b/lib/cache/lvmcache.c
index 0d13c16..1586f30 100644
--- a/lib/cache/lvmcache.c
+++ b/lib/cache/lvmcache.c
@@ -67,6 +67,7 @@ struct lvmcache_vginfo {
unsigned vg_use_count; /* Counter of vg reusage */
unsigned precommitted; /* Is vgmetadata live or precommitted? */
unsigned cached_vg_invalidated; /* Signal to regenerate cached_vg */
+ unsigned preferred_duplicates; /* preferred duplicate pvs have been set */
};
static struct dm_hash_table *_pvid_hash = NULL;
@@ -115,6 +116,47 @@ int lvmcache_init(void)
return 1;
}
+/*
+ * Once PV info has been populated in lvmcache and
+ * lvmcache has chosen preferred duplicate devices,
+ * set this flag so that lvmcache will not try to
+ * compare and choose preferred duplicate devices
+ * again (which may result in different preferred
+ * devices.) PV info can be populated in lvmcache
+ * multiple times, each time causing lvmcache to
+ * compare the duplicate devices, so we need to
+ * record that the comparison/preferences have
+ * already been done, so the preferrences from the
+ * first time through are not changed.
+ *
+ * This is something of a hack to work around the
+ * fact that the code isn't really designed to
+ * handle duplicate PVs, and the fact that lvmetad
+ * has its own way of picking a preferred duplicate
+ * and lvmcache has another way based on having
+ * more information than lvmetad does.
+ *
+ * If we come up with a better overall method to
+ * handle duplicate PVs, then this can probably be
+ * removed.
+ *
+ * FIXME: if we want to make lvmetad work with clvmd,
+ * then this may need to be changed to set
+ * preferred_duplicates back to 0.
+ */
+
+void lvmcache_set_preferred_duplicates(const char *vgid)
+{
+ struct lvmcache_vginfo *vginfo;
+
+ if (!(vginfo = lvmcache_vginfo_from_vgid(vgid))) {
+ stack;
+ return;
+ }
+
+ vginfo->preferred_duplicates = 1;
+}
+
void lvmcache_seed_infos_from_lvmetad(struct cmd_context *cmd)
{
if (!lvmetad_active() || _has_scanned)
@@ -1689,6 +1731,18 @@ struct lvmcache_info *lvmcache_add(struct labeller *labeller, const
char *pvid,
dev_name(dev));
}
+ if (existing->vginfo->preferred_duplicates) {
+ /*
+ * The preferred duplicate devs have already
+ * been chosen during a previous populating of
+ * lvmcache, so just use the existing preferences.
+ */
+ log_verbose("Found duplicate PV %s: using existing dev %s",
+ pvid_s,
+ dev_name(existing->dev));
+ return NULL;
+ }
+
if (old_in_subsystem && !new_in_subsystem) {
/* Use old, ignore new. */
log_warn("Found duplicate PV %s: using %s not %s",
@@ -1741,7 +1795,7 @@ struct lvmcache_info *lvmcache_add(struct labeller *labeller, const
char *pvid,
pvid_s,
dev_name(dev),
dev_name(existing->dev));
- log_warn("Using duplicate PV %s which is more recent, replacing %s",
+ log_warn("Using duplicate PV %s which is last seen, replacing %s",
dev_name(dev),
dev_name(existing->dev));
@@ -1754,7 +1808,7 @@ struct lvmcache_info *lvmcache_add(struct labeller *labeller, const
char *pvid,
pvid_s,
dev_name(dev),
dev_name(existing->dev));
- log_warn("Using duplicate PV %s which is more recent, replacing %s",
+ log_warn("Using duplicate PV %s which is last seen, replacing %s",
dev_name(dev),
dev_name(existing->dev));
}
diff --git a/lib/cache/lvmcache.h b/lib/cache/lvmcache.h
index 6c4c927..6a43204 100644
--- a/lib/cache/lvmcache.h
+++ b/lib/cache/lvmcache.h
@@ -171,4 +171,6 @@ void lvmcache_replace_dev(struct cmd_context *cmd, struct
physical_volume *pv,
int lvmcache_found_duplicate_pvs(void);
+void lvmcache_set_preferred_duplicates(const char *vgid);
+
#endif
diff --git a/lib/cache/lvmetad.c b/lib/cache/lvmetad.c
index 00a84b5..fd0630f 100644
--- a/lib/cache/lvmetad.c
+++ b/lib/cache/lvmetad.c
@@ -265,9 +265,9 @@ static int _read_mda(struct lvmcache_info *info,
return 0;
}
-static struct lvmcache_info *_pv_populate_lvmcache(struct cmd_context *cmd,
- struct dm_config_node *cn,
- struct format_type *fmt, dev_t fallback)
+static int _pv_populate_lvmcache(struct cmd_context *cmd,
+ struct dm_config_node *cn,
+ struct format_type *fmt, dev_t fallback)
{
struct device *dev, *dev_alternate, *dev_alternate_cache = NULL;
struct label *label;
@@ -293,7 +293,7 @@ static struct lvmcache_info *_pv_populate_lvmcache(struct cmd_context
*cmd,
if (!fmt) {
log_error("PV %s not recognised. Is the device missing?", pvid_txt);
- return NULL;
+ return 0;
}
dev = dev_cache_get_by_devt(devt, cmd->filter);
@@ -302,17 +302,17 @@ static struct lvmcache_info *_pv_populate_lvmcache(struct
cmd_context *cmd,
if (!dev) {
log_warn("WARNING: Device for PV %s not found or rejected by a filter.",
pvid_txt);
- return NULL;
+ return 0;
}
if (!pvid_txt || !id_read_format(&pvid, pvid_txt)) {
log_error("Missing or ill-formatted PVID for PV: %s.", pvid_txt);
- return NULL;
+ return 0;
}
if (vgid_txt) {
if (!id_read_format(&vgid, vgid_txt))
- return_NULL;
+ return_0;
} else
strcpy((char*)&vgid, fmt->orphan_vg_name);
@@ -321,7 +321,7 @@ static struct lvmcache_info *_pv_populate_lvmcache(struct cmd_context
*cmd,
if (!(info = lvmcache_add(fmt->labeller, (const char *)&pvid, dev,
vgname, (const char *)&vgid, 0)))
- return_NULL;
+ return_0;
lvmcache_get_label(info)->sector = label_sector;
lvmcache_get_label(info)->dev = dev;
@@ -390,7 +390,8 @@ static struct lvmcache_info *_pv_populate_lvmcache(struct cmd_context
*cmd,
}
}
- return info;
+ lvmcache_set_preferred_duplicates((const char *)&vgid);
+ return 1;
}
struct volume_group *lvmetad_vg_lookup(struct cmd_context *cmd, const char *vgname, const
char *vgid)