On 2011-05-30 11:30, Boaz Harrosh wrote:
>
> As talk to with Trond, when a client has sent an nfs4_close, the
> server can surly assume that the given client has already forgotten
> all it's ROC given layouts. And in fact the current Linux-client goes
> to grate length to make sure all ROC layouts are invalidated, before
> sending the close. If a new open+IO comes in and tries to get a new layout,
> it will wait for the nfs4_close to return before sending the new layout_get.
>
> So in light of above the server should simulate layout_return and remove
> any layouts marked ROC on nfs4_close.
>
> Current code is protocol correct, but a more fine-grained approach can be
> devised to also release layouts in open_downgrade, of all unused iomodes.
> But to do this I'll need the help of an expert.
>
> With this patch in, I'm finally able to run with the new Linux-Client together
> with a Linux-Server. Before, the layouts where only released and freed on umount
> and in a modest machine like the UML I use, few 10s of "git checkout linux" the
> server would oom.
>
> Benny please submit it to the pnfs tree, so we can run with this in Bakeathone.
>
> So please all help me to verify and refine this code.
>
> Signed-off-by: Boaz Harrosh <bharrosh@xxxxxxxxxxx>
> ---
> fs/nfsd/nfs4pnfsd.c | 44 ++++++++++++++++++++++++++++++++++++++++++--
> fs/nfsd/nfs4state.c | 3 +++
> fs/nfsd/pnfsd.h | 3 +++
> 3 files changed, 48 insertions(+), 2 deletions(-)
>
> diff --git a/fs/nfsd/nfs4pnfsd.c b/fs/nfsd/nfs4pnfsd.c
> index 9089e6b9..d8f744e 100644
> --- a/fs/nfsd/nfs4pnfsd.c
> +++ b/fs/nfsd/nfs4pnfsd.c
> @@ -402,7 +402,8 @@ init_layout(struct nfs4_layout_state *ls,
> struct nfs4_client *clp,
> struct svc_fh *current_fh,
> struct nfsd4_layout_seg *seg,
> - stateid_t *stateid)
> + stateid_t *stateid,
> + bool roc)
> {
> dprintk("pNFS %s: ls %p lp %p clp %p fp %p ino %p\n", __func__,
> ls, lp, clp, fp, fp->fi_inode);
> @@ -412,6 +413,7 @@ init_layout(struct nfs4_layout_state *ls,
> lp->lo_file = fp;
> get_layout_state(ls);
> lp->lo_state = ls;
> + lp->lo_roc = roc;
> memcpy(&lp->lo_seg, seg, sizeof(lp->lo_seg));
> spin_lock(&layout_lock);
> update_layout_stateid(ls, stateid);
> @@ -914,7 +916,8 @@ nfs4_pnfs_get_layout(struct nfsd4_pnfs_layoutget *lgp,
> goto out_freelayout;
>
> /* Can't merge, so let's initialize this new layout */
> - init_layout(ls, lp, fp, clp, lgp->lg_fhp, &res.lg_seg, &lgp->lg_sid);
> + init_layout(ls, lp, fp, clp, lgp->lg_fhp, &res.lg_seg, &lgp->lg_sid,
> + res.lg_return_on_close);
> out_unlock:
> if (ls)
> put_layout_state(ls);
> @@ -1328,6 +1331,43 @@ nomatching_layout(struct nfs4_layoutrecall *clr)
> iput(inode);
> }
>
> +/* Return On Close:
> + * Look for all layouts of @fp that belong to @clp, if ROC is set, remove
> + * the layout and simulate a layout_return. Surly the client has forgotten
> + * these layouts or it would return them before the close.
> + */
> +void pnfs_roc(struct nfs4_client *clp, struct nfs4_file *fp,
> + enum pnfs_iomode iomode)
> +{
> + struct nfs4_layout *lo, *nextlp;
> +
> + spin_lock(&layout_lock);
> + list_for_each_entry_safe (lo, nextlp, &fp->fi_layouts, lo_perfile) {
> + struct nfsd4_pnfs_layoutreturn lr;
> + bool empty;
> +
> + /* Check for a match */
> + if (!lo->lo_roc ||
> + (lo->lo_client != clp) ||
> + ((iomode != IOMODE_ANY) && (lo->lo_seg.iomode != iomode))
> + )
> + continue;
> +
> + /* Return the layout */
> + memset(&lr, 0, sizeof(lr));
> + lr.args.lr_return_type = RETURN_FILE;
> + lr.args.lr_seg = lo->lo_seg;
> + dequeue_layout(lo);
> + destroy_layout(lo); /* do not access lp after this */
> +
> + empty = list_empty(&fp->fi_layouts);
> + fs_layout_return(fp->fi_inode->i_sb, fp->fi_inode, &lr,
> + LR_FLAG_EXPIRE,
> + empty ? PNFS_LAST_LAYOUT_NO_RECALLS : NULL);
> + }
> + spin_unlock(&layout_lock);
> +}
> +
> void pnfs_expire_client(struct nfs4_client *clp)
> {
> for (;;) {
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 66f6f48..a116e41 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -3592,6 +3592,9 @@ nfsd4_close(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
> /* release_stateid() calls nfsd_close() if needed */
> release_open_stateid(stp);
>
> + /* RFC: what to do with IOMODE */
> + pnfs_roc(stp->st_stateowner->so_client, stp->st_file, IOMODE_ANY);
> +
Ouch, moving this call before release_open_stateid as it frees stop.
(and removing the iomode parameter)
Benny
> /* place unused nfs4_stateowners on so_close_lru list to be
> * released by the laundromat service after the lease period
> * to enable us to handle CLOSE replay
> diff --git a/fs/nfsd/pnfsd.h b/fs/nfsd/pnfsd.h
> index c11d93d..fcb16d2 100644
> --- a/fs/nfsd/pnfsd.h
> +++ b/fs/nfsd/pnfsd.h
> @@ -59,6 +59,7 @@ struct nfs4_layout {
> struct nfs4_client *lo_client;
> struct nfs4_layout_state *lo_state;
> struct nfsd4_layout_seg lo_seg;
> + bool lo_roc;
> };
>
> struct pnfs_inval_state {
> @@ -124,6 +125,8 @@ int nfs4_pnfs_cb_change_state(struct pnfs_get_state *);
> void nfs4_ds_get_verifier(stateid_t *, struct super_block *, u32 *);
> int put_layoutrecall(struct nfs4_layoutrecall *);
> void nomatching_layout(struct nfs4_layoutrecall *);
> +void pnfs_roc(struct nfs4_client *clp, struct nfs4_file *fp,
> + enum pnfs_iomode iomode);
> void *layoutrecall_done(struct nfs4_layoutrecall *);
> void nfsd4_cb_layout(struct nfs4_layoutrecall *);
> int nfsd_layout_recall_cb(struct super_block *, struct inode *,
--
To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
