On 20 Jun 2024, at 10:15, Christoph Hellwig wrote:
> On Thu, Jun 20, 2024 at 09:52:59AM -0400, Benjamin Coddington wrote:
>> On 20 Jun 2024, at 1:06, Christoph Hellwig wrote:
>>
>>> On Wed, Jun 19, 2024 at 01:39:33PM -0400, cel@xxxxxxxxxx wrote:
>>>> - if (test_bit(NFS_DEVICEID_UNAVAILABLE, &node->flags) == 0)
>>>> + if (test_bit(NFS_DEVICEID_UNAVAILABLE, &node->flags) == 0) {
>>>
>>> It might be worth to invert this and keep the unavailable handling in
>>> the branch as that's the exceptional case. That code is also woefully
>>> under-documented and could have really used a comment.
>>
>> The transient device handling in general, or just this bit of it?
>
> Basically the code behind this NFS_DEVICEID_UNAVAILABLE check here.
How about..
diff --git a/fs/nfs/blocklayout/blocklayout.c b/fs/nfs/blocklayout/blocklayout.c
index 6be13e0ec170..665c054784b4 100644
--- a/fs/nfs/blocklayout/blocklayout.c
+++ b/fs/nfs/blocklayout/blocklayout.c
@@ -564,25 +564,30 @@ bl_find_get_deviceid(struct nfs_server *server,
gfp_t gfp_mask)
{
struct nfs4_deviceid_node *node;
- unsigned long start, end;
retry:
node = nfs4_find_get_deviceid(server, id, cred, gfp_mask);
if (!node)
return ERR_PTR(-ENODEV);
- if (test_bit(NFS_DEVICEID_UNAVAILABLE, &node->flags) == 0)
- return node;
+ /* Transient devices are left in the cache with a timeout to minimize
+ * sending GETDEVINFO after every LAYOUTGET */
+ if (test_bit(NFS_DEVICEID_UNAVAILABLE, &node->flags)) {
+ unsigned long start, end;
- end = jiffies;
- start = end - PNFS_DEVICE_RETRY_TIMEOUT;
- if (!time_in_range(node->timestamp_unavailable, start, end)) {
- nfs4_delete_deviceid(node->ld, node->nfs_client, id);
- goto retry;
+ end = jiffies;
+ start = end - PNFS_DEVICE_RETRY_TIMEOUT;
+
+ /* Maybe the device is back, let's look for it again */
+ if (!time_in_range(node->timestamp_unavailable, start, end)) {
+ nfs4_delete_deviceid(node->ld, node->nfs_client, id);
+ goto retry;
+ }
+ nfs4_put_deviceid_node(node);
+ return ERR_PTR(-ENODEV);
}
- nfs4_put_deviceid_node(node);
- return ERR_PTR(-ENODEV);
+ return node;
}
static int
