process_each_pv: do full scan earlier to find new devicesdev-dct-dev-cache-full-scan

Before commit c1f246fedfc349c25749da501e68a7f70bd122b0,
_get_all_devices() did a full device scan before
get_vgnameids() was called.  New devices would be
added to the dev-cache before label scanning done
by get_vgnameids.  So, labels would be read from
new devices by the first 'pvs' command.

After that commit, _get_all_devices() was called
after get_vgnameids() was finished with label scanning.
So, new devices would be missed by the label scanning,
and would not appear to be lvm devices to the first
'pvs' command.  A new device would be added to .cache
by the first command, so the second 'pvs' command would
scan labels from it in get_vgnameids().

Now, the full device scan is factored out of
get_all_devices() and called by itself at the
start of the command so that new devices will
be known before get_vgnameids() scans labels.

1 files changed, 8 insertions, 1 deletions

diff --git a/lib/cache/lvmcache.c b/lib/cache/lvmcache.c
index 799de6f6e..2a01ec2cb 100644
--- a/lib/cache/lvmcache.c
+++ b/lib/cache/lvmcache.c
@@ -749,6 +749,7 @@ int lvmcache_label_scan(struct cmd_context *cmd, int full_scan)
 	struct dev_iter *iter;
 	struct device *dev;
 	struct format_type *fmt;
+	int dev_count = 0;
 
 	int r = 0;
 
@@ -779,11 +780,17 @@ int lvmcache_label_scan(struct cmd_context *cmd, int full_scan)
 		goto out;
 	}
 
-	while ((dev = dev_iter_get(iter)))
+	log_very_verbose("Scanning device labels");
+
+	while ((dev = dev_iter_get(iter))) {
 		(void) label_read(dev, &label, UINT64_C(0));
+		dev_count++;
+	}
 
 	dev_iter_destroy(iter);
 
+	log_very_verbose("Scanned %d device labels", dev_count);
+
 	_has_scanned = 1;
 
 	/* Perform any format-specific scanning e.g. text files */