alistair23-linux/net/sunrpc/xprtrdma/physical_ops.c
Chuck Lever d654788e98 xprtrdma: Make rpcrdma_{un}map_one() into inline functions
These functions are called in a loop for each page transferred via
RDMA READ or WRITE. Extract loop invariants and inline them to
reduce CPU overhead.

Signed-off-by: Chuck Lever <chuck.lever@oracle.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>
2015-03-31 09:52:53 -04:00

95 lines
2.2 KiB
C

/*
* 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
static int
physical_op_open(struct rpcrdma_ia *ia, struct rpcrdma_ep *ep,
struct rpcrdma_create_data_internal *cdata)
{
return 0;
}
/* PHYSICAL memory registration conveys one page per chunk segment.
*/
static size_t
physical_op_maxpages(struct rpcrdma_xprt *r_xprt)
{
return min_t(unsigned int, RPCRDMA_MAX_DATA_SEGS,
rpcrdma_max_segments(r_xprt));
}
static int
physical_op_init(struct rpcrdma_xprt *r_xprt)
{
return 0;
}
/* The client's physical memory is already exposed for
* remote access via RDMA READ or RDMA WRITE.
*/
static int
physical_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg,
int nsegs, bool writing)
{
struct rpcrdma_ia *ia = &r_xprt->rx_ia;
rpcrdma_map_one(ia->ri_id->device, seg,
rpcrdma_data_dir(writing));
seg->mr_rkey = ia->ri_bind_mem->rkey;
seg->mr_base = seg->mr_dma;
seg->mr_nsegs = 1;
return 1;
}
/* Unmap a memory region, but leave it registered.
*/
static int
physical_op_unmap(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg)
{
struct rpcrdma_ia *ia = &r_xprt->rx_ia;
read_lock(&ia->ri_qplock);
rpcrdma_unmap_one(ia->ri_id->device, seg);
read_unlock(&ia->ri_qplock);
return 1;
}
static void
physical_op_reset(struct rpcrdma_xprt *r_xprt)
{
}
static void
physical_op_destroy(struct rpcrdma_buffer *buf)
{
}
const struct rpcrdma_memreg_ops rpcrdma_physical_memreg_ops = {
.ro_map = physical_op_map,
.ro_unmap = physical_op_unmap,
.ro_open = physical_op_open,
.ro_maxpages = physical_op_maxpages,
.ro_init = physical_op_init,
.ro_reset = physical_op_reset,
.ro_destroy = physical_op_destroy,
.ro_displayname = "physical",
};