xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

xprtrdma: Chunk list encoders no longer share one rl_segments array

Browse Source 
Currently, all three chunk list encoders each use a portion of the
one rl_segments array in rpcrdma_req. This is because the MWs for
each chunk list were preserved in rl_segments so that ro_unmap could
find and invalidate them after the RPC was complete.

However, now that MWs are placed on a per-req linked list as they
are registered, there is no longer any information in rpcrdma_mr_seg
that is shared between ro_map and ro_unmap_{sync,safe}, and thus
nothing in rl_segments needs to be preserved after
rpcrdma_marshal_req is complete.

Thus the rl_segments array can be used now just for the needs of
each rpcrdma_convert_iovs call. Once each chunk list is encoded, the
next chunk list encoder is free to re-use all of rl_segments.

This means all three chunk lists in one RPC request can now each
encode a full size data payload with no increase in the size of
rl_segments.

This is a key requirement for Kerberos support, since both the Call
and Reply for a single RPC transaction are conveyed via Long
messages (RDMA Read/Write). Both can be large.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This commit is contained in:
Chuck Lever
2016-06-29 13:54:25 -04:00
committed by Anna Schumaker
parent 9d6b040978
commit 5ab8142839
2 changed files with 44 additions and 53 deletions
Download Patch File Download Diff File Expand all files Collapse all files

36
net/sunrpc/xprtrdma/xprt_rdma.h
View File

@@ -171,23 +171,14 @@ rdmab_to_msg(struct rpcrdma_regbuf *rb)
* o recv buffer (posted to provider)
* o ib_sge (also donated to provider)
* o status of reply (length, success or not)
* o bookkeeping state to get run by tasklet (list, etc)
* o bookkeeping state to get run by reply handler (list, etc)
*
* These are allocated during initialization, per-transport instance;
* however, the tasklet execution list itself is global, as it should
* always be pretty short.
* These are allocated during initialization, per-transport instance.
*
* N of these are associated with a transport instance, and stored in
* struct rpcrdma_buffer. N is the max number of outstanding requests.
*/
#define RPCRDMA_MAX_DATA_SEGS ((1 * 1024 * 1024) / PAGE_SIZE)
/* data segments + head/tail for Call + head/tail for Reply */
#define RPCRDMA_MAX_SEGS (RPCRDMA_MAX_DATA_SEGS + 4)
struct rpcrdma_buffer;
struct rpcrdma_rep {
struct ib_cqe rr_cqe;
unsigned int rr_len;
@@ -267,13 +258,18 @@ struct rpcrdma_mw {
* of iovs for send operations. The reason is that the iovs passed to
* ib_post_{send,recv} must not be modified until the work request
* completes.
*
* NOTES:
* o RPCRDMA_MAX_SEGS is the max number of addressible chunk elements we
* marshal. The number needed varies depending on the iov lists that
* are passed to us and the memory registration mode we are in.
*/
/* Maximum number of page-sized "segments" per chunk list to be
* registered or invalidated. Must handle a Reply chunk:
*/
enum {
RPCRDMA_MAX_IOV_SEGS = 3,
RPCRDMA_MAX_DATA_SEGS = ((1 * 1024 * 1024) / PAGE_SIZE) + 1,
RPCRDMA_MAX_SEGS = RPCRDMA_MAX_DATA_SEGS +
RPCRDMA_MAX_IOV_SEGS,
};
struct rpcrdma_mr_seg { /* chunk descriptors */
u32 mr_len; /* length of chunk or segment */
struct page *mr_page; /* owning page, if any */
@@ -282,10 +278,10 @@ struct rpcrdma_mr_seg { /* chunk descriptors */
#define RPCRDMA_MAX_IOVS (2)
struct rpcrdma_buffer;
struct rpcrdma_req {
struct list_head rl_free;
unsigned int rl_niovs;
unsigned int rl_nchunks;
unsigned int rl_connect_cookie;
struct rpc_task *rl_task;
struct rpcrdma_buffer *rl_buffer;
@@ -293,13 +289,13 @@ struct rpcrdma_req {
struct ib_sge rl_send_iov[RPCRDMA_MAX_IOVS];
struct rpcrdma_regbuf *rl_rdmabuf;
struct rpcrdma_regbuf *rl_sendbuf;
struct list_head rl_registered; /* registered segments */
struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS];
struct rpcrdma_mr_seg *rl_nextseg;
struct ib_cqe rl_cqe;
struct list_head rl_all;
bool rl_backchannel;
struct list_head rl_registered; /* registered segments */
struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS];
};
static inline struct rpcrdma_req *