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91141b8eb9
Now that the pool mode is always pernode, svc_serv.sv_nrpools is redundant with sv_is_pooled: an unpooled service always has a single pool, and a pooled service has svc_pool_map.npools pools (which is one on a single-node host). sv_nrpools cannot distinguish an unpooled service from a pooled service that happens to have one pool, so it is sv_nrpools, not sv_is_pooled, that carries no unique information. Replace the cached field with a svc_serv_nrpools() helper that derives the count from sv_is_pooled and the pool map, and convert all readers to it. svc_pool_map is file-local to svc.c, so export the helper for the svc_xprt.c and nfsd callers. Reading svc_pool_map.npools without svc_pool_map_mutex is safe: the mutex protects only svc_pool_map.count, and npools is already read locklessly in svc_pool_for_cpu(). A pooled service holds a map reference for its whole lifetime, so npools is stable while any reader could observe it. The hot path (svc_pool_for_cpu()) already dereferences svc_pool_map for to_pool, and npools shares that cacheline, so there is no new locking or coherence cost. __svc_create() keeps using its local npools argument for the sv_pools[] allocation, since sv_is_pooled is not set until svc_create_pooled() has returned from it. Doing this also removes a modulus operation from svc_pool_for_cpu(), which should make for more efficient RPC queueing. Assisted-by: Claude:claude-opus-4-8 Suggested-by: NeilBrown <neilb@ownmail.net> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260706-sunrpc-pool-mode-v5-5-6c4ee7cd89aa@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>