xprtrdma: Avoid 250 ms delay on backlog wakeup

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Commit a721035477 ("SUNRPC/xprt: async tasks mustn't block waiting
for memory") changed xprt_rdma_alloc_slot() to set tk_status to
-ENOMEM so that call_reserveresult() would sleep HZ/4 before
retrying.  That rationale applies to xprt_dynamic_alloc_slot(),
where an immediate retry under memory pressure wastes CPU, but not
to the RDMA backlog path: a task woken from the backlog has a slot
waiting for it, so the 250 ms rpc_delay adds latency without
benefit.

This also aligns the code with the existing kernel-doc for
xprt_rdma_alloc_slot(), which already documented %-EAGAIN.

Fixes: a721035477 ("SUNRPC/xprt: async tasks mustn't block waiting for memory")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

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Chuck Lever 2026-03-06 16:56:23 -05:00 • committed by Trond Myklebust

parent 24297c7cd3

commit 100142093e

1 changed files with 1 additions and 1 deletions

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net/sunrpc/xprtrdma/transport.c

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