[PATCH] knfsd: split svc_serv into pools
Split out the list of idle threads and pending sockets from svc_serv into a
new svc_pool structure, and allocate a fixed number (in this patch, 1) of
pools per svc_serv. The new structure contains a lock which takes over
several of the duties of svc_serv->sv_lock, which is now relegated to
protecting only sv_tempsocks, sv_permsocks, and sv_tmpcnt in svc_serv.
The point is to move the hottest fields out of svc_serv and into svc_pool,
allowing a following patch to arrange for a svc_pool per NUMA node or per CPU.
This is a major step towards making the NFS server NUMA-friendly.
Signed-off-by: Greg Banks <gnb@melbourne.sgi.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h
index 5eabded..c27d806 100644
--- a/include/linux/sunrpc/svc.h
+++ b/include/linux/sunrpc/svc.h
@@ -17,6 +17,25 @@
#include <linux/wait.h>
#include <linux/mm.h>
+
+/*
+ *
+ * RPC service thread pool.
+ *
+ * Pool of threads and temporary sockets. Generally there is only
+ * a single one of these per RPC service, but on NUMA machines those
+ * services that can benefit from it (i.e. nfs but not lockd) will
+ * have one pool per NUMA node. This optimisation reduces cross-
+ * node traffic on multi-node NUMA NFS servers.
+ */
+struct svc_pool {
+ unsigned int sp_id; /* pool id; also node id on NUMA */
+ spinlock_t sp_lock; /* protects all fields */
+ struct list_head sp_threads; /* idle server threads */
+ struct list_head sp_sockets; /* pending sockets */
+ unsigned int sp_nrthreads; /* # of threads in pool */
+} ____cacheline_aligned_in_smp;
+
/*
* RPC service.
*
@@ -28,8 +47,6 @@
* We currently do not support more than one RPC program per daemon.
*/
struct svc_serv {
- struct list_head sv_threads; /* idle server threads */
- struct list_head sv_sockets; /* pending sockets */
struct svc_program * sv_program; /* RPC program */
struct svc_stat * sv_stats; /* RPC statistics */
spinlock_t sv_lock;
@@ -44,6 +61,9 @@
char * sv_name; /* service name */
+ unsigned int sv_nrpools; /* number of thread pools */
+ struct svc_pool * sv_pools; /* array of thread pools */
+
void (*sv_shutdown)(struct svc_serv *serv);
/* Callback to use when last thread
* exits.
@@ -138,6 +158,7 @@
int rq_addrlen;
struct svc_serv * rq_server; /* RPC service definition */
+ struct svc_pool * rq_pool; /* thread pool */
struct svc_procedure * rq_procinfo; /* procedure info */
struct auth_ops * rq_authop; /* authentication flavour */
struct svc_cred rq_cred; /* auth info */