[lvm-devel] master - dmeventd: thin plugin umount over 95%
Zdenek Kabelac
zkabelac at fedoraproject.org
Thu Jun 30 22:46:00 UTC 2016
Gitweb: http://git.fedorahosted.org/git/?p=lvm2.git;a=commitdiff;h=2f638e07e814617152d617a2ca7c8acdae41968a
Commit: 2f638e07e814617152d617a2ca7c8acdae41968a
Parent: 103c188681fce748ef193115c126bfbbc65fbab9
Author: Zdenek Kabelac <zkabelac at redhat.com>
AuthorDate: Wed Jun 29 15:56:29 2016 +0200
Committer: Zdenek Kabelac <zkabelac at redhat.com>
CommitterDate: Fri Jul 1 00:43:45 2016 +0200
dmeventd: thin plugin umount over 95%
Run umount code only when either thin data or metadata are
above 95% - so if there are resize failures with 60%.
system fill keep running.
Also umount will only be tried with lvm2 LVs.
Foreign users are ATM unsuppored.
---
WHATS_NEW_DM | 1 +
daemons/dmeventd/plugins/thin/dmeventd_thin.c | 99 ++++++++++++++++++++++---
2 files changed, 89 insertions(+), 11 deletions(-)
diff --git a/WHATS_NEW_DM b/WHATS_NEW_DM
index 5043c23..30d6d82 100644
--- a/WHATS_NEW_DM
+++ b/WHATS_NEW_DM
@@ -1,5 +1,6 @@
Version 1.02.129 -
=================================
+ Thin dmeventd plugin umounts lvm2 volume only when pool is 95% or more.
Version 1.02.128 - 25th June 2016
=================================
diff --git a/daemons/dmeventd/plugins/thin/dmeventd_thin.c b/daemons/dmeventd/plugins/thin/dmeventd_thin.c
index 0cef168..c27cf50 100644
--- a/daemons/dmeventd/plugins/thin/dmeventd_thin.c
+++ b/daemons/dmeventd/plugins/thin/dmeventd_thin.c
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2011-2015 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2011-2016 Red Hat, Inc. All rights reserved.
*
* This file is part of LVM2.
*
@@ -30,6 +30,9 @@
/* First warning when thin data or metadata is 80% full. */
#define WARNING_THRESH (DM_PERCENT_1 * 80)
+/* Umount thin LVs when thin data or metadata LV is >=
+ * and lvextend --use-policies has failed. */
+#define UMOUNT_THRESH (DM_PERCENT_1 * 95)
/* Run a check every 5%. */
#define CHECK_STEP (DM_PERCENT_1 * 5)
/* Do not bother checking thin data or metadata is less than 50% full. */
@@ -53,6 +56,53 @@ struct dso_state {
DM_EVENT_LOG_FN("thin")
+#define UUID_PREFIX "LVM-"
+
+/* Figure out device UUID has LVM- prefix and is OPEN */
+static int _has_unmountable_prefix(int major, int minor)
+{
+ struct dm_task *dmt;
+ struct dm_info info;
+ const char *uuid;
+ int r = 0;
+
+ if (!(dmt = dm_task_create(DM_DEVICE_INFO)))
+ return_0;
+
+ if (!dm_task_set_major_minor(dmt, major, minor, 1))
+ goto_out;
+
+ if (!dm_task_no_flush(dmt))
+ stack;
+
+ if (!dm_task_run(dmt))
+ goto out;
+
+ if (!dm_task_get_info(dmt, &info))
+ goto out;
+
+ if (!info.exists || !info.open_count)
+ goto out; /* Not open -> not mounted */
+
+ if (!(uuid = dm_task_get_uuid(dmt)))
+ goto out;
+
+ /* Check it's public mountable LV
+ * has prefix LVM- and UUID size is 68 chars */
+ if (memcmp(uuid, UUID_PREFIX, sizeof(UUID_PREFIX) - 1) ||
+ strlen(uuid) != 68)
+ goto out;
+
+#if THIN_DEBUG
+ log_debug("Found LV (%u:%u) %s.", major, minor, uuid);
+#endif
+ r = 1;
+out:
+ dm_task_destroy(dmt);
+
+ return r;
+}
+
/* Get dependencies for device, and try to find matching device */
static int _has_deps(const char *name, int tp_major, int tp_minor, int *dev_minor)
{
@@ -90,6 +140,9 @@ static int _has_deps(const char *name, int tp_major, int tp_minor, int *dev_mino
*dev_minor = info.minor;
+ if (!_has_unmountable_prefix(major, info.minor))
+ goto out;
+
#if THIN_DEBUG
{
char dev_name[PATH_MAX];
@@ -206,7 +259,7 @@ static int _umount_device(char *buffer, unsigned major, unsigned minor,
}
/*
- * Find all thin pool users and try to umount them.
+ * Find all thin pool LV users and try to umount them.
* TODO: work with read-only thin pool support
*/
static void _umount(struct dm_task *dmt)
@@ -240,7 +293,7 @@ out:
dm_bitset_destroy(data.minors);
}
-static void _use_policy(struct dm_task *dmt, struct dso_state *state)
+static int _use_policy(struct dm_task *dmt, struct dso_state *state)
{
#if THIN_DEBUG
log_info("dmeventd executes: %s.", state->cmd_str);
@@ -248,10 +301,12 @@ static void _use_policy(struct dm_task *dmt, struct dso_state *state)
if (!dmeventd_lvm2_run_with_lock(state->cmd_str)) {
log_error("Failed to extend thin pool %s.",
dm_task_get_name(dmt));
- _umount(dmt);
state->fails++;
- } else
- state->fails = 0;
+ return 0;
+ }
+
+ state->fails = 0;
+ return 1;
}
void process_event(struct dm_task *dmt,
@@ -267,6 +322,13 @@ void process_event(struct dm_task *dmt,
char *target_type = NULL;
char *params;
int needs_policy = 0;
+ int needs_umount = 0;
+
+#if THIN_DEBUG
+ log_debug("Watch for tp-data:%.2f%% tp-metadata:%.2f%%.",
+ dm_percent_to_float(state->data_percent_check),
+ dm_percent_to_float(state->metadata_percent_check));
+#endif
#if 0
/* No longer monitoring, waiting for remove */
@@ -275,8 +337,10 @@ void process_event(struct dm_task *dmt,
#endif
if (event & DM_EVENT_DEVICE_ERROR) {
/* Error -> no need to check and do instant resize */
- _use_policy(dmt, state);
- goto out;
+ if (_use_policy(dmt, state))
+ goto out;
+
+ stack;
}
dm_get_next_target(dmt, next, &start, &length, &target_type, ¶ms);
@@ -288,7 +352,7 @@ void process_event(struct dm_task *dmt,
if (!dm_get_status_thin_pool(state->mem, params, &tps)) {
log_error("Failed to parse status.");
- _umount(dmt);
+ needs_umount = 1;
goto out;
}
@@ -323,6 +387,9 @@ void process_event(struct dm_task *dmt,
log_warn("WARNING: Thin pool %s metadata is now %.2f%% full.",
device, dm_percent_to_float(percent));
needs_policy = 1;
+
+ if (percent >= UMOUNT_THRESH)
+ needs_umount = 1;
}
percent = dm_make_percent(tps->used_data_blocks, tps->total_data_blocks);
@@ -337,11 +404,21 @@ void process_event(struct dm_task *dmt,
log_warn("WARNING: Thin pool %s data is now %.2f%% full.",
device, dm_percent_to_float(percent));
needs_policy = 1;
+
+ if (percent >= UMOUNT_THRESH)
+ needs_umount = 1;
}
- if (needs_policy)
- _use_policy(dmt, state);
+ if (needs_policy &&
+ _use_policy(dmt, state))
+ needs_umount = 0; /* No umount when command was successful */
out:
+ if (needs_umount) {
+ _umount(dmt);
+ /* Until something changes, do not retry any more actions */
+ state->data_percent_check = state->metadata_percent_check = (DM_PERCENT_1 * 101);
+ }
+
if (tps)
dm_pool_free(state->mem, tps);
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