forked from Minki/linux
48be539dd4
rpcrdma_buffer_get acquires an rpcrdma_req and rep for each RPC. Currently this is done in the call_allocate action, and sometimes it can fail if there are many outstanding RPCs. When call_allocate fails, the RPC task is put on the delayq. It is awoken a few milliseconds later, but there's no guarantee it will get a buffer at that time. The RPC task can be repeatedly put back to sleep or even starved. The call_allocate action should rarely fail. The delayq mechanism is not meant to deal with transport congestion. In the current sunrpc stack, there is a friendlier way to deal with this situation. These objects are actually tantamount to an RPC slot (rpc_rqst) and there is a separate FSM action, distinct from call_allocate, for allocating slot resources. This is the call_reserve action. When allocation fails during this action, the RPC is placed on the transport's backlog queue. The backlog mechanism provides a stronger guarantee that when the RPC is awoken, a buffer will be available for it; and backlogged RPCs are awoken one-at-a-time. To make slot resource allocation occur in the call_reserve action, create special ->alloc_slot and ->free_slot call-outs for xprtrdma. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> |
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| .. | ||
| auth_gss | ||
| xprtrdma | ||
| addr.c | ||
| auth_generic.c | ||
| auth_null.c | ||
| auth_unix.c | ||
| auth.c | ||
| backchannel_rqst.c | ||
| cache.c | ||
| clnt.c | ||
| debugfs.c | ||
| Kconfig | ||
| Makefile | ||
| netns.h | ||
| rpc_pipe.c | ||
| rpcb_clnt.c | ||
| sched.c | ||
| socklib.c | ||
| stats.c | ||
| sunrpc_syms.c | ||
| sunrpc.h | ||
| svc_xprt.c | ||
| svc.c | ||
| svcauth_unix.c | ||
| svcauth.c | ||
| svcsock.c | ||
| sysctl.c | ||
| timer.c | ||
| xdr.c | ||
| xprt.c | ||
| xprtmultipath.c | ||
| xprtsock.c | ||