Return-Path: Received: from mail-wi0-f173.google.com ([209.85.212.173]:38382 "EHLO mail-wi0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754829AbbITMka (ORCPT ); Sun, 20 Sep 2015 08:40:30 -0400 Received: by wiclk2 with SMTP id lk2so79517775wic.1 for ; Sun, 20 Sep 2015 05:40:28 -0700 (PDT) Subject: Re: [PATCH v1 15/18] svcrdma: Add svc_rdma_get_context() API that is allowed to fail To: Chuck Lever , linux-rdma@vger.kernel.org, linux-nfs@vger.kernel.org References: <20150917202829.19671.90044.stgit@manet.1015granger.net> <20150917204614.19671.61606.stgit@manet.1015granger.net> From: Sagi Grimberg Message-ID: <55FEA951.8000106@dev.mellanox.co.il> Date: Sun, 20 Sep 2015 15:40:49 +0300 MIME-Version: 1.0 In-Reply-To: <20150917204614.19671.61606.stgit@manet.1015granger.net> Content-Type: text/plain; charset=utf-8; format=flowed Sender: linux-nfs-owner@vger.kernel.org List-ID: On 9/17/2015 11:46 PM, Chuck Lever wrote: > To support backward direction calls, I'm going to add an > svc_rdma_get_context() call in the client RDMA transport. > > Called from ->buf_alloc(), we can't sleep waiting for memory. > So add an API that can get a server op_ctxt but won't sleep. > > Signed-off-by: Chuck Lever > --- > include/linux/sunrpc/svc_rdma.h | 2 ++ > net/sunrpc/xprtrdma/svc_rdma_transport.c | 28 +++++++++++++++++++++++----- > 2 files changed, 25 insertions(+), 5 deletions(-) > > diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h > index 6ce7495..2500dd1 100644 > --- a/include/linux/sunrpc/svc_rdma.h > +++ b/include/linux/sunrpc/svc_rdma.h > @@ -224,6 +224,8 @@ extern void svc_rdma_send_error(struct svcxprt_rdma *, struct rpcrdma_msg *, > extern int svc_rdma_post_recv(struct svcxprt_rdma *); > extern int svc_rdma_create_listen(struct svc_serv *, int, struct sockaddr *); > extern struct svc_rdma_op_ctxt *svc_rdma_get_context(struct svcxprt_rdma *); > +extern struct svc_rdma_op_ctxt *svc_rdma_get_context_gfp(struct svcxprt_rdma *, > + gfp_t); > extern void svc_rdma_put_context(struct svc_rdma_op_ctxt *, int); > extern void svc_rdma_unmap_dma(struct svc_rdma_op_ctxt *ctxt); > extern struct svc_rdma_req_map *svc_rdma_get_req_map(void); > diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c > index 23aba30..c4083a3 100644 > --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c > +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c > @@ -153,17 +153,35 @@ static void svc_rdma_bc_free(struct svc_xprt *xprt) > } > #endif /* CONFIG_SUNRPC_BACKCHANNEL */ > > -struct svc_rdma_op_ctxt *svc_rdma_get_context(struct svcxprt_rdma *xprt) > +static void svc_rdma_init_context(struct svcxprt_rdma *xprt, > + struct svc_rdma_op_ctxt *ctxt) > { > - struct svc_rdma_op_ctxt *ctxt; > - > - ctxt = kmem_cache_alloc(svc_rdma_ctxt_cachep, > - GFP_KERNEL | __GFP_NOFAIL); > ctxt->xprt = xprt; > INIT_LIST_HEAD(&ctxt->dto_q); > ctxt->count = 0; > ctxt->frmr = NULL; > atomic_inc(&xprt->sc_ctxt_used); > +} > + > +struct svc_rdma_op_ctxt *svc_rdma_get_context_gfp(struct svcxprt_rdma *xprt, > + gfp_t flags) > +{ > + struct svc_rdma_op_ctxt *ctxt; > + > + ctxt = kmem_cache_alloc(svc_rdma_ctxt_cachep, flags); > + if (!ctxt) > + return NULL; > + svc_rdma_init_context(xprt, ctxt); > + return ctxt; > +} > + > +struct svc_rdma_op_ctxt *svc_rdma_get_context(struct svcxprt_rdma *xprt) > +{ Why not: return svc_rdma_get_context_gfp(xprt, GFP_KERNEL | __GFP_NOFAIL); ? > + struct svc_rdma_op_ctxt *ctxt; > + > + ctxt = kmem_cache_alloc(svc_rdma_ctxt_cachep, > + GFP_KERNEL | __GFP_NOFAIL); > + svc_rdma_init_context(xprt, ctxt); > return ctxt; > } > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-rdma" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >