[lvm-devel] master - scan: move warnings about duplicate devices
David Teigland
teigland at sourceware.org
Tue May 22 15:01:32 UTC 2018
Gitweb: https://sourceware.org/git/?p=lvm2.git;a=commitdiff;h=3c9ed33f83c90aa15e57ba6dc12d8f1a80afab6d
Commit: 3c9ed33f83c90aa15e57ba6dc12d8f1a80afab6d
Parent: 73ae68e1c4308c3391fe3b21f2c721f659343f98
Author: David Teigland <teigland at redhat.com>
AuthorDate: Mon May 21 14:20:19 2018 -0500
Committer: David Teigland <teigland at redhat.com>
CommitterDate: Mon May 21 16:48:02 2018 -0500
scan: move warnings about duplicate devices
We have been warning about duplicate devices (and disabling lvmetad)
immediately when the dup was detected (during label_scan). Move the
warnings (and the disabling) to happen later, after label_scan is
finished.
This lets us avoid an unwanted warning message about duplicates
in the special case were md components are eliminated during the
duplicate device resolution.
---
lib/cache/lvmcache.c | 125 ++++++++++++++++++++++++++----
lib/cache/lvmcache.h | 2 +
lib/cache/lvmetad.c | 2 +
lib/device/device.h | 1 +
test/shell/process-each-duplicate-pvs.sh | 22 +++---
test/shell/pv-duplicate-uuid.sh | 5 +-
6 files changed, 126 insertions(+), 31 deletions(-)
diff --git a/lib/cache/lvmcache.c b/lib/cache/lvmcache.c
index 9912995..c306a3a 100644
--- a/lib/cache/lvmcache.c
+++ b/lib/cache/lvmcache.c
@@ -981,11 +981,25 @@ int lvmcache_dev_is_unchosen_duplicate(struct device *dev)
* The actual filters are evaluated too early, before a complete
* picture of all PVs is available, to eliminate these duplicates.
*
- * By removing the filtered duplicates from unused_duplicate_devs, we remove
+ * By removing some duplicates from unused_duplicate_devs here, we remove
* the restrictions that are placed on using duplicate devs or VGs with
* duplicate devs.
*
- * There may other kinds of duplicates that we want to ignore.
+ * In cases where we know that two duplicates refer to the same underlying
+ * storage, and we know which dev path to use, it's best for us to just
+ * use that one preferred device path and ignore the others. It is the cases
+ * where we are unsure whether dups refer to the same underlying storage where
+ * we need to keep the unused duplicate referenced in the
+ * unused_duplicate_devs list, and restrict what we allow done with it.
+ *
+ * In the case of md components, we usually filter these out in filter-md,
+ * but in the special case of md superblocks <= 1.0 where the superblock
+ * is at the end of the device, filter-md doesn't always eliminate them
+ * first, so we eliminate them here.
+ *
+ * There may other kinds of duplicates that we want to eliminate at
+ * this point (using the knowledge from the scan) that we couldn't
+ * eliminate in the filters prior to the scan.
*/
static void _filter_duplicate_devs(struct cmd_context *cmd)
@@ -1004,6 +1018,34 @@ static void _filter_duplicate_devs(struct cmd_context *cmd)
dm_free(devl);
}
}
+
+ if (dm_list_empty(&_unused_duplicate_devs))
+ _found_duplicate_pvs = 0;
+}
+
+static void _warn_duplicate_devs(struct cmd_context *cmd)
+{
+ char uuid[64] __attribute__((aligned(8)));
+ struct lvmcache_info *info;
+ struct device_list *devl, *devl2;
+
+ dm_list_iterate_items_safe(devl, devl2, &_unused_duplicate_devs) {
+ if (!id_write_format((const struct id *)devl->dev->pvid, uuid, sizeof(uuid)))
+ stack;
+
+ log_warn("WARNING: Not using device %s for PV %s.", dev_name(devl->dev), uuid);
+ }
+
+ dm_list_iterate_items_safe(devl, devl2, &_unused_duplicate_devs) {
+ /* info for the preferred device that we're actually using */
+ info = lvmcache_info_from_pvid(devl->dev->pvid, NULL, 0);
+
+ if (!id_write_format((const struct id *)info->dev->pvid, uuid, sizeof(uuid)))
+ stack;
+
+ log_warn("WARNING: PV %s prefers device %s because %s.",
+ uuid, dev_name(info->dev), info->dev->duplicate_prefer_reason);
+ }
}
/*
@@ -1028,7 +1070,6 @@ static void _choose_preferred_devs(struct cmd_context *cmd,
struct dm_list *del_cache_devs,
struct dm_list *add_cache_devs)
{
- char uuid[64] __attribute__((aligned(8)));
const char *reason;
struct dm_list altdevs;
struct dm_list new_unused;
@@ -1229,9 +1270,7 @@ next:
alt = devl;
}
- if (!id_write_format((const struct id *)dev1->pvid, uuid, sizeof(uuid)))
- stack;
- log_warn("WARNING: PV %s prefers device %s because %s.", uuid, dev_name(dev1), reason);
+ dev1->duplicate_prefer_reason = reason;
}
if (dev1 != info->dev) {
@@ -1480,11 +1519,21 @@ int lvmcache_label_scan(struct cmd_context *cmd)
dm_list_splice(&_unused_duplicate_devs, &del_cache_devs);
/*
- * We might want to move the duplicate device warnings until
- * after this filtering so that we can skip warning about
- * duplicates that we are filtering out.
+ * This may remove some entries from the unused_duplicates list for
+ * devs that we know are the same underlying dev.
*/
_filter_duplicate_devs(cmd);
+
+ /*
+ * Warn about remaining duplicates that may actually be separate copies of
+ * the same device.
+ */
+ _warn_duplicate_devs(cmd);
+
+ if (!_found_duplicate_pvs && lvmetad_used()) {
+ log_warn("WARNING: Disabling lvmetad cache which does not support duplicate PVs.");
+ lvmetad_set_disabled(cmd, LVMETAD_DISABLE_REASON_DUPLICATES);
+ }
}
/* Perform any format-specific scanning e.g. text files */
@@ -1509,6 +1558,53 @@ int lvmcache_label_scan(struct cmd_context *cmd)
return r;
}
+/*
+ * When not using lvmetad, lvmcache_label_scan() detects duplicates in
+ * the basic label_scan(), then filters out some dups, and chooses
+ * preferred duplicates to use.
+ *
+ * When using lvmetad, pvscan --cache does not use lvmcache_label_scan(),
+ * only label_scan() which detects the duplicates. This function is used
+ * after pvscan's label_scan() to filter out some dups, print any warnings,
+ * and disable lvmetad if any dups are left.
+ */
+
+void lvmcache_pvscan_duplicate_check(struct cmd_context *cmd)
+{
+ struct device_list *devl;
+
+ /* Check if label_scan() detected any dups. */
+ if (!_found_duplicate_pvs)
+ return;
+
+ /*
+ * Once all the dups are identified, they are moved from the
+ * "found" list to the "unused" list to sort out.
+ */
+ dm_list_splice(&_unused_duplicate_devs, &_found_duplicate_devs);
+
+ /*
+ * Remove items from the dups list that we know are the same
+ * underlying dev, e.g. md components, that we want to just ignore.
+ */
+ _filter_duplicate_devs(cmd);
+
+ /*
+ * If no more dups after ignoring some, then we can use lvmetad.
+ */
+ if (!_found_duplicate_pvs)
+ return;
+
+ /* Duplicates are found where we would have to pick one, so disable lvmetad. */
+
+ dm_list_iterate_items(devl, &_unused_duplicate_devs)
+ log_warn("WARNING: found device with duplicate %s", dev_name(devl->dev));
+
+ log_warn("WARNING: Disabling lvmetad cache which does not support duplicate PVs.");
+ lvmetad_set_disabled(cmd, LVMETAD_DISABLE_REASON_DUPLICATES);
+ lvmetad_make_unused(cmd);
+}
+
int lvmcache_get_vgnameids(struct cmd_context *cmd, int include_internal,
struct dm_list *vgnameids)
{
@@ -2303,14 +2399,8 @@ struct lvmcache_info *lvmcache_add(struct labeller *labeller,
*/
if (!created) {
if (info->dev != dev) {
- log_warn("WARNING: PV %s on %s was already found on %s.",
- uuid, dev_name(dev), dev_name(info->dev));
-
- if (!_found_duplicate_pvs && lvmetad_used()) {
- log_warn("WARNING: Disabling lvmetad cache which does not support duplicate PVs.");
- lvmetad_set_disabled(labeller->fmt->cmd, LVMETAD_DISABLE_REASON_DUPLICATES);
- }
- _found_duplicate_pvs = 1;
+ log_debug_cache("PV %s on %s was already found on %s.",
+ uuid, dev_name(dev), dev_name(info->dev));
strncpy(dev->pvid, pvid_s, sizeof(dev->pvid));
@@ -2328,6 +2418,7 @@ struct lvmcache_info *lvmcache_add(struct labeller *labeller,
devl->dev = dev;
dm_list_add(&_found_duplicate_devs, &devl->list);
+ _found_duplicate_pvs = 1;
return NULL;
}
diff --git a/lib/cache/lvmcache.h b/lib/cache/lvmcache.h
index a2a7f07..b988be6 100644
--- a/lib/cache/lvmcache.h
+++ b/lib/cache/lvmcache.h
@@ -188,6 +188,8 @@ uint64_t lvmcache_smallest_mda_size(struct lvmcache_info *info);
int lvmcache_found_duplicate_pvs(void);
+void lvmcache_pvscan_duplicate_check(struct cmd_context *cmd);
+
int lvmcache_get_unused_duplicate_devs(struct cmd_context *cmd, struct dm_list *head);
int vg_has_duplicate_pvs(struct volume_group *vg);
diff --git a/lib/cache/lvmetad.c b/lib/cache/lvmetad.c
index 235f72b..a1ab41a 100644
--- a/lib/cache/lvmetad.c
+++ b/lib/cache/lvmetad.c
@@ -2350,6 +2350,8 @@ int lvmetad_pvscan_all_devs(struct cmd_context *cmd, int do_wait)
label_scan(cmd);
+ lvmcache_pvscan_duplicate_check(cmd);
+
if (lvmcache_found_duplicate_pvs()) {
log_warn("WARNING: Scan found duplicate PVs.");
return 0;
diff --git a/lib/device/device.h b/lib/device/device.h
index 42659cd..c8ccd73 100644
--- a/lib/device/device.h
+++ b/lib/device/device.h
@@ -75,6 +75,7 @@ struct device {
uint64_t size;
uint64_t end;
struct dev_ext ext;
+ const char *duplicate_prefer_reason;
const char *vgid; /* if device is an LV */
const char *lvid; /* if device is an LV */
diff --git a/test/shell/process-each-duplicate-pvs.sh b/test/shell/process-each-duplicate-pvs.sh
index 98dd285..9ce4e14 100644
--- a/test/shell/process-each-duplicate-pvs.sh
+++ b/test/shell/process-each-duplicate-pvs.sh
@@ -72,7 +72,7 @@ not grep duplicate main
not grep $vg2 main
not grep $UUID2 main
-grep "was already found on" warn
+grep "Not using device" warn
grep "prefers device" warn
# Find which is the preferred dev and which is the duplicate.
@@ -119,7 +119,7 @@ grep "$dev2" main | grep $vg1
grep "$dev1" main | grep $UUID1
grep "$dev2" main | grep $UUID1
-grep "was already found on" warn
+grep "Not using device" warn
grep "prefers device" warn
#
@@ -136,7 +136,7 @@ grep "$dev1" main
not grep "$dev2" main
grep "$UUID1" main
grep "$vg1" main
-grep "was already found on" warn
+grep "Not using device" warn
grep "prefers device" warn
pvs -o+uuid "$dev2" 2>&1 | tee out
@@ -149,7 +149,7 @@ grep "$dev2" main
not grep "$dev1" main
grep "$UUID1" main
grep "$vg1" main
-grep "was already found on" warn
+grep "Not using device" warn
grep "prefers device" warn
pvs -o+uuid,duplicate "$dev1" "$dev2" 2>&1 | tee out
@@ -225,7 +225,7 @@ grep -v WARNING out > main || true
not grep "$dev1" main
grep "$dev2" main
-not grep "was already found on" warn
+not grep "Not using device" warn
not grep "prefers device" warn
@@ -238,7 +238,7 @@ grep -v WARNING out > main || true
grep "$dev1" main
not grep "$dev2" main
-not grep "was already found on" warn
+not grep "Not using device" warn
not grep "prefers device" warn
# PV size and minor is still reported correctly for each.
@@ -306,7 +306,7 @@ grep -v WARNING out > main || true
test "$(grep -c "$UUID3" main)" -eq 1
not grep "$UUID4" main
-grep "was already found on" warn
+grep "Not using device" warn
grep "prefers device" warn
# Both appear with 'pvs -a'
@@ -325,7 +325,7 @@ grep "$dev4" main
grep $UUID3 main
not grep $UUID4 main
-grep "was already found on" warn
+grep "Not using device" warn
grep "prefers device" warn
# Show each dev individually and both together
@@ -339,7 +339,7 @@ grep -v WARNING out > main || true
grep "$dev3" main
not grep "$dev4" main
-grep "was already found on" warn
+grep "Not using device" warn
grep "prefers device" warn
pvs -o+uuid "$dev4" 2>&1 | tee out
@@ -351,7 +351,7 @@ grep -v WARNING out > main || true
not grep "$dev3" main
grep "$dev4" main
-grep "was already found on" warn
+grep "Not using device" warn
grep "prefers device" warn
pvs -o+uuid "$dev3" "$dev4" 2>&1 | tee out
@@ -363,7 +363,7 @@ grep -v WARNING out > main || true
grep "$dev3" main
grep "$dev4" main
-grep "was already found on" warn
+grep "Not using device" warn
grep "prefers device" warn
# Same sizes shown.
diff --git a/test/shell/pv-duplicate-uuid.sh b/test/shell/pv-duplicate-uuid.sh
index 43eb830..2c121d7 100644
--- a/test/shell/pv-duplicate-uuid.sh
+++ b/test/shell/pv-duplicate-uuid.sh
@@ -26,7 +26,6 @@ pvcreate --config "devices{filter=[\"a|$dev3|\",\"r|.*|\"]} global/use_lvmetad=0
pvscan --cache 2>&1 | tee out
if test -e LOCAL_LVMETAD; then
- grep "was already found" out
grep "WARNING: Disabling lvmetad cache which does not support duplicate PVs." out
fi
@@ -37,7 +36,7 @@ grep -v WARNING out > main || true
test "$(grep -c $UUID1 main)" -eq 1
-COUNT=$(grep --count "was already found" warn)
+COUNT=$(grep --count "Not using device" warn)
[ "$COUNT" -eq 2 ]
pvs -o+uuid --config "devices{filter=[\"a|$dev2|\",\"r|.*|\"]}" 2>&1 | tee out
@@ -50,5 +49,5 @@ not grep "$dev1" main
grep "$dev2" main
not grep "$dev3" main
-not grep "was already found" warn
+not grep "Not using device" warn
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