From: Trond Myklebust Date: Mon, 18 Jun 2018 23:07:24 +0000 (-0400) Subject: pNFS/flexfiles: Don't tie up all the rpciod threads in resends X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=42f86b44a4d356edba626171dfe0be061fc695af;p=linux.git pNFS/flexfiles: Don't tie up all the rpciod threads in resends We do not want to have rpciod threads perform recursive calls into the RPC layer since that can deadlock. In particular, having to wait for a layoutget can be nasty... We want rather to defer scheduling those retries until we're in the rpc_release() callback, since that is called from the nfsiod workqueue. Signed-off-by: Trond Myklebust --- diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c index 3ae038d9c2926..336b4d560e2c5 100644 --- a/fs/nfs/flexfilelayout/flexfilelayout.c +++ b/fs/nfs/flexfilelayout/flexfilelayout.c @@ -1243,17 +1243,18 @@ static int ff_layout_read_done_cb(struct rpc_task *task, hdr->ds_clp, hdr->lseg, hdr->pgio_mirror_idx); + clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags); + clear_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags); switch (err) { case -NFS4ERR_RESET_TO_PNFS: if (ff_layout_choose_best_ds_for_read(hdr->lseg, hdr->pgio_mirror_idx + 1, &hdr->pgio_mirror_idx)) goto out_eagain; - ff_layout_read_record_layoutstats_done(task, hdr); - pnfs_read_resend_pnfs(hdr); + set_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags); return task->tk_status; case -NFS4ERR_RESET_TO_MDS: - ff_layout_reset_read(hdr); + set_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags); return task->tk_status; case -EAGAIN: goto out_eagain; @@ -1403,6 +1404,10 @@ static void ff_layout_read_release(void *data) struct nfs_pgio_header *hdr = data; ff_layout_read_record_layoutstats_done(&hdr->task, hdr); + if (test_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags)) + pnfs_read_resend_pnfs(hdr); + else if (test_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags)) + ff_layout_reset_read(hdr); pnfs_generic_rw_release(data); } diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h index 9dee3c23895d8..712eed156d091 100644 --- a/include/linux/nfs_xdr.h +++ b/include/linux/nfs_xdr.h @@ -1438,6 +1438,8 @@ enum { NFS_IOHDR_EOF, NFS_IOHDR_REDO, NFS_IOHDR_STAT, + NFS_IOHDR_RESEND_PNFS, + NFS_IOHDR_RESEND_MDS, }; struct nfs_io_completion;