Thread (31 messages) 31 messages, 5 authors, 2024-05-22

Re: [PATCH md-6.10 3/9] md: add new helpers for sync_action

From: Su Yue <hidden>
Date: 2024-05-20 12:38:28
Also in: dm-devel, lkml

On Thu 09 May 2024 at 09:18, Yu Kuai [off-list ref] 
wrote:
quoted hunk ↗ jump to hunk
From: Yu Kuai <redacted>

The new helpers will get current sync_action of the array, will 
be used
in later patches to make code cleaner.

Signed-off-by: Yu Kuai <redacted>
---
 drivers/md/md.c | 64 
 +++++++++++++++++++++++++++++++++++++++++++++++++
 drivers/md/md.h |  3 +++
 2 files changed, 67 insertions(+)
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 00bbafcd27bb..48ec35342d1b 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -69,6 +69,16 @@
 #include "md-bitmap.h"
 #include "md-cluster.h"

+static char *action_name[NR_SYNC_ACTIONS] = {
Th array will not be modified, so:

static const char * const action_names[NR_SYNC_ACTIONS]
quoted hunk ↗ jump to hunk
+	[ACTION_RESYNC]		= "resync",
+	[ACTION_RECOVER]	= "recover",
+	[ACTION_CHECK]		= "check",
+	[ACTION_REPAIR]		= "repair",
+	[ACTION_RESHAPE]	= "reshape",
+	[ACTION_FROZEN]		= "frozen",
+	[ACTION_IDLE]		= "idle",
+};
+
 /* pers_list is a list of registered personalities protected by 
 pers_lock. */
 static LIST_HEAD(pers_list);
 static DEFINE_SPINLOCK(pers_lock);
@@ -4867,6 +4877,60 @@ metadata_store(struct mddev *mddev, const 
char *buf, size_t len)
 static struct md_sysfs_entry md_metadata =
 __ATTR_PREALLOC(metadata_version, S_IRUGO|S_IWUSR, 
 metadata_show, metadata_store);

+enum sync_action md_sync_action(struct mddev *mddev)
+{
+	unsigned long recovery = mddev->recovery;
+
+	/*
+	 * frozen has the highest priority, means running sync_thread 
will be
+	 * stopped immediately, and no new sync_thread can start.
+	 */
+	if (test_bit(MD_RECOVERY_FROZEN, &recovery))
+		return ACTION_FROZEN;
+
+	/*
+	 * idle means no sync_thread is running, and no new 
sync_thread is
+	 * requested.
+	 */
+	if (!test_bit(MD_RECOVERY_RUNNING, &recovery) &&
+	    (!md_is_rdwr(mddev) || !test_bit(MD_RECOVERY_NEEDED, 
&recovery)))
+		return ACTION_IDLE;
My brain was lost sometimes looking into nested conditions of md 
code...
I agree with Xiao Ni's suggestion that more comments about the 
array
state should be added.
+	if (test_bit(MD_RECOVERY_RESHAPE, &recovery) ||
+	    mddev->reshape_position != MaxSector)
+		return ACTION_RESHAPE;
+
+	if (test_bit(MD_RECOVERY_RECOVER, &recovery))
+		return ACTION_RECOVER;
+
In action_show, MD_RECOVERY_SYNC is tested first then 
MD_RECOVERY_RECOVER.
After looking through the logic of MD_RECOVERY_RECOVER 
clear/set_bit, the
change is fine to me. However, better to follow old pattern unless 
there
have resons.

+	if (test_bit(MD_RECOVERY_SYNC, &recovery)) {
+		if (test_bit(MD_RECOVERY_CHECK, &recovery))
+			return ACTION_CHECK;
+		if (test_bit(MD_RECOVERY_REQUESTED, &recovery))
+			return ACTION_REPAIR;
+		return ACTION_RESYNC;
+	}
+
+	return ACTION_IDLE;
+}
+
+enum sync_action md_sync_action_by_name(char *page)
+{
+	enum sync_action action;
+
+	for (action = 0; action < NR_SYNC_ACTIONS; ++action) {
+		if (cmd_match(page, action_name[action]))
+			return action;
+	}
+
+	return NR_SYNC_ACTIONS;
+}
+
+char *md_sync_action_name(enum sync_action action)
And 'const char *'

--
Su
quoted hunk ↗ jump to hunk
+{
+	return action_name[action];
+}
+
 static ssize_t
 action_show(struct mddev *mddev, char *page)
 {
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 2edad966f90a..72ca7a796df5 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -864,6 +864,9 @@ extern void md_unregister_thread(struct 
mddev *mddev, struct md_thread __rcu **t
 extern void md_wakeup_thread(struct md_thread __rcu *thread);
 extern void md_check_recovery(struct mddev *mddev);
 extern void md_reap_sync_thread(struct mddev *mddev);
+extern enum sync_action md_sync_action(struct mddev *mddev);
+extern enum sync_action md_sync_action_by_name(char *page);
+extern char *md_sync_action_name(enum sync_action action);
 extern bool md_write_start(struct mddev *mddev, struct bio 
 *bi);
 extern void md_write_inc(struct mddev *mddev, struct bio *bi);
 extern void md_write_end(struct mddev *mddev);
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help