NFSv4.1: turn off pNFS on ds connection failure

If a data server is unavailable, go through MDS.

Mark the deviceid containing the data server as a negative cache entry.
Do not try to connect to any data server on a deviceid marked as a negative
cache entry. Mark any layout that tries to use the marked deviceid as failed.

Inodes with a layout marked as fails will not use the layout for I/O, and will
not perform any more layoutgets.
Inodes without a layout will still do layoutget, but the layout will get
marked immediately.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Andy Adamson 2011-03-01 01:34:22 +00:00 committed by Trond Myklebust
parent ea8eecdd11
commit 568e8c494d
4 changed files with 36 additions and 9 deletions

View File

@ -214,7 +214,9 @@ filelayout_read_pagelist(struct nfs_read_data *data)
idx = nfs4_fl_calc_ds_index(lseg, j);
ds = nfs4_fl_prepare_ds(lseg, idx);
if (!ds) {
printk(KERN_ERR "%s: prepare_ds failed, use MDS\n", __func__);
/* Either layout fh index faulty, or ds connect failed */
set_bit(lo_fail_bit(IOMODE_RW), &lseg->pls_layout->plh_flags);
set_bit(lo_fail_bit(IOMODE_READ), &lseg->pls_layout->plh_flags);
return PNFS_NOT_ATTEMPTED;
}
dprintk("%s USE DS:ip %x %hu\n", __func__,

View File

@ -55,10 +55,14 @@ struct nfs4_pnfs_ds {
atomic_t ds_count;
};
/* nfs4_file_layout_dsaddr flags */
#define NFS4_DEVICE_ID_NEG_ENTRY 0x00000001
struct nfs4_file_layout_dsaddr {
struct hlist_node node;
struct nfs4_deviceid deviceid;
atomic_t ref;
unsigned long flags;
u32 stripe_count;
u8 *stripe_indices;
u32 ds_num;

View File

@ -606,6 +606,21 @@ nfs4_fl_select_ds_fh(struct pnfs_layout_segment *lseg, u32 j)
return flseg->fh_array[i];
}
static void
filelayout_mark_devid_negative(struct nfs4_file_layout_dsaddr *dsaddr,
int err, u32 ds_addr)
{
u32 *p = (u32 *)&dsaddr->deviceid;
printk(KERN_ERR "NFS: data server %x connection error %d."
" Deviceid [%x%x%x%x] marked out of use.\n",
ds_addr, err, p[0], p[1], p[2], p[3]);
spin_lock(&filelayout_deviceid_lock);
dsaddr->flags |= NFS4_DEVICE_ID_NEG_ENTRY;
spin_unlock(&filelayout_deviceid_lock);
}
struct nfs4_pnfs_ds *
nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx)
{
@ -619,13 +634,18 @@ nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx)
}
if (!ds->ds_clp) {
struct nfs_server *s = NFS_SERVER(lseg->pls_layout->plh_inode);
int err;
err = nfs4_ds_connect(NFS_SERVER(lseg->pls_layout->plh_inode),
dsaddr->ds_list[ds_idx]);
if (dsaddr->flags & NFS4_DEVICE_ID_NEG_ENTRY) {
/* Already tried to connect, don't try again */
dprintk("%s Deviceid marked out of use\n", __func__);
return NULL;
}
err = nfs4_ds_connect(s, ds);
if (err) {
printk(KERN_ERR "%s nfs4_ds_connect error %d\n",
__func__, err);
filelayout_mark_devid_negative(dsaddr, err,
ntohl(ds->ds_ip_addr));
return NULL;
}
}

View File

@ -739,15 +739,16 @@ pnfs_update_layout(struct inode *ino,
dprintk("%s matches recall, use MDS\n", __func__);
goto out_unlock;
}
/* Check to see if the layout for the given range already exists */
lseg = pnfs_find_lseg(lo, iomode);
if (lseg)
goto out_unlock;
/* if LAYOUTGET already failed once we don't try again */
if (test_bit(lo_fail_bit(iomode), &nfsi->layout->plh_flags))
goto out_unlock;
/* Check to see if the layout for the given range already exists */
lseg = pnfs_find_lseg(lo, iomode);
if (lseg)
goto out_unlock;
if (pnfs_layoutgets_blocked(lo, NULL, 0))
goto out_unlock;
atomic_inc(&lo->plh_outstanding);