xprtrdma: Add vector of ops for each memory registration strategy

Instead of employing switch() statements, let's use the typical
Linux kernel idiom for handling behavioral variation: virtual
functions.

Start by defining a vector of operations for each supported memory
registration mode, and by adding a source file for each mode.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Tested-by: Devesh Sharma <Devesh.Sharma@Emulex.Com>
Tested-by: Meghana Cheripady <Meghana.Cheripady@Emulex.Com>
Tested-by: Veeresh U. Kokatnur <veereshuk@chelsio.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This commit is contained in:
Chuck Lever 2015-03-30 14:34:21 -04:00 committed by Anna Schumaker
parent 41f9702896
commit a0ce85f595
6 changed files with 89 additions and 5 deletions

View File

@ -1,6 +1,7 @@
obj-$(CONFIG_SUNRPC_XPRT_RDMA_CLIENT) += xprtrdma.o
xprtrdma-y := transport.o rpc_rdma.o verbs.o
xprtrdma-y := transport.o rpc_rdma.o verbs.o \
fmr_ops.o frwr_ops.o physical_ops.o
obj-$(CONFIG_SUNRPC_XPRT_RDMA_SERVER) += svcrdma.o

View File

@ -0,0 +1,22 @@
/*
* Copyright (c) 2015 Oracle. All rights reserved.
* Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
*/
/* Lightweight memory registration using Fast Memory Regions (FMR).
* Referred to sometimes as MTHCAFMR mode.
*
* FMR uses synchronous memory registration and deregistration.
* FMR registration is known to be fast, but FMR deregistration
* can take tens of usecs to complete.
*/
#include "xprt_rdma.h"
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
# define RPCDBG_FACILITY RPCDBG_TRANS
#endif
const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops = {
.ro_displayname = "fmr",
};

View File

@ -0,0 +1,22 @@
/*
* Copyright (c) 2015 Oracle. All rights reserved.
* Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
*/
/* Lightweight memory registration using Fast Registration Work
* Requests (FRWR). Also referred to sometimes as FRMR mode.
*
* FRWR features ordered asynchronous registration and deregistration
* of arbitrarily sized memory regions. This is the fastest and safest
* but most complex memory registration mode.
*/
#include "xprt_rdma.h"
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
# define RPCDBG_FACILITY RPCDBG_TRANS
#endif
const struct rpcrdma_memreg_ops rpcrdma_frwr_memreg_ops = {
.ro_displayname = "frwr",
};

View File

@ -0,0 +1,24 @@
/*
* Copyright (c) 2015 Oracle. All rights reserved.
* Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
*/
/* No-op chunk preparation. All client memory is pre-registered.
* Sometimes referred to as ALLPHYSICAL mode.
*
* Physical registration is simple because all client memory is
* pre-registered and never deregistered. This mode is good for
* adapter bring up, but is considered not safe: the server is
* trusted not to abuse its access to client memory not involved
* in RDMA I/O.
*/
#include "xprt_rdma.h"
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
# define RPCDBG_FACILITY RPCDBG_TRANS
#endif
const struct rpcrdma_memreg_ops rpcrdma_physical_memreg_ops = {
.ro_displayname = "physical",
};

View File

@ -492,10 +492,10 @@ connected:
int ird = attr->max_dest_rd_atomic;
int tird = ep->rep_remote_cma.responder_resources;
pr_info("rpcrdma: connection to %pIS:%u on %s, memreg %d slots %d ird %d%s\n",
pr_info("rpcrdma: connection to %pIS:%u on %s, memreg '%s', %d credits, %d responders%s\n",
sap, rpc_get_port(sap),
ia->ri_id->device->name,
ia->ri_memreg_strategy,
ia->ri_ops->ro_displayname,
xprt->rx_buf.rb_max_requests,
ird, ird < 4 && ird < tird / 2 ? " (low!)" : "");
} else if (connstate < 0) {
@ -650,13 +650,16 @@ rpcrdma_ia_open(struct rpcrdma_xprt *xprt, struct sockaddr *addr, int memreg)
*/
switch (memreg) {
case RPCRDMA_FRMR:
ia->ri_ops = &rpcrdma_frwr_memreg_ops;
break;
case RPCRDMA_ALLPHYSICAL:
ia->ri_ops = &rpcrdma_physical_memreg_ops;
mem_priv = IB_ACCESS_LOCAL_WRITE |
IB_ACCESS_REMOTE_WRITE |
IB_ACCESS_REMOTE_READ;
goto register_setup;
case RPCRDMA_MTHCAFMR:
ia->ri_ops = &rpcrdma_fmr_memreg_ops;
if (ia->ri_have_dma_lkey)
break;
mem_priv = IB_ACCESS_LOCAL_WRITE;
@ -676,8 +679,8 @@ rpcrdma_ia_open(struct rpcrdma_xprt *xprt, struct sockaddr *addr, int memreg)
rc = -ENOMEM;
goto out3;
}
dprintk("RPC: %s: memory registration strategy is %d\n",
__func__, memreg);
dprintk("RPC: %s: memory registration strategy is '%s'\n",
__func__, ia->ri_ops->ro_displayname);
/* Else will do memory reg/dereg for each chunk */
ia->ri_memreg_strategy = memreg;

View File

@ -60,6 +60,7 @@
* Interface Adapter -- one per transport instance
*/
struct rpcrdma_ia {
const struct rpcrdma_memreg_ops *ri_ops;
rwlock_t ri_qplock;
struct rdma_cm_id *ri_id;
struct ib_pd *ri_pd;
@ -330,6 +331,17 @@ struct rpcrdma_stats {
unsigned long bad_reply_count;
};
/*
* Per-registration mode operations
*/
struct rpcrdma_memreg_ops {
const char *ro_displayname;
};
extern const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops;
extern const struct rpcrdma_memreg_ops rpcrdma_frwr_memreg_ops;
extern const struct rpcrdma_memreg_ops rpcrdma_physical_memreg_ops;
/*
* RPCRDMA transport -- encapsulates the structures above for
* integration with RPC.