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-rw-r--r--net/sunrpc/svc.c457
1 files changed, 447 insertions, 10 deletions
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 44b8d9d4c18..a99e67b164c 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -4,6 +4,10 @@
* High-level RPC service routines
*
* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
+ *
+ * Multiple threads pools and NUMAisation
+ * Copyright (c) 2006 Silicon Graphics, Inc.
+ * by Greg Banks <gnb@melbourne.sgi.com>
*/
#include <linux/linkage.h>
@@ -12,6 +16,8 @@
#include <linux/net.h>
#include <linux/in.h>
#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
#include <linux/sunrpc/types.h>
#include <linux/sunrpc/xdr.h>
@@ -23,14 +29,252 @@
#define RPC_PARANOIA 1
/*
+ * Mode for mapping cpus to pools.
+ */
+enum {
+ SVC_POOL_NONE = -1, /* uninitialised, choose one of the others */
+ SVC_POOL_GLOBAL, /* no mapping, just a single global pool
+ * (legacy & UP mode) */
+ SVC_POOL_PERCPU, /* one pool per cpu */
+ SVC_POOL_PERNODE /* one pool per numa node */
+};
+
+/*
+ * Structure for mapping cpus to pools and vice versa.
+ * Setup once during sunrpc initialisation.
+ */
+static struct svc_pool_map {
+ int mode; /* Note: int not enum to avoid
+ * warnings about "enumeration value
+ * not handled in switch" */
+ unsigned int npools;
+ unsigned int *pool_to; /* maps pool id to cpu or node */
+ unsigned int *to_pool; /* maps cpu or node to pool id */
+} svc_pool_map = {
+ .mode = SVC_POOL_NONE
+};
+
+
+/*
+ * Detect best pool mapping mode heuristically,
+ * according to the machine's topology.
+ */
+static int
+svc_pool_map_choose_mode(void)
+{
+ unsigned int node;
+
+ if (num_online_nodes() > 1) {
+ /*
+ * Actually have multiple NUMA nodes,
+ * so split pools on NUMA node boundaries
+ */
+ return SVC_POOL_PERNODE;
+ }
+
+ node = any_online_node(node_online_map);
+ if (nr_cpus_node(node) > 2) {
+ /*
+ * Non-trivial SMP, or CONFIG_NUMA on
+ * non-NUMA hardware, e.g. with a generic
+ * x86_64 kernel on Xeons. In this case we
+ * want to divide the pools on cpu boundaries.
+ */
+ return SVC_POOL_PERCPU;
+ }
+
+ /* default: one global pool */
+ return SVC_POOL_GLOBAL;
+}
+
+/*
+ * Allocate the to_pool[] and pool_to[] arrays.
+ * Returns 0 on success or an errno.
+ */
+static int
+svc_pool_map_alloc_arrays(struct svc_pool_map *m, unsigned int maxpools)
+{
+ m->to_pool = kcalloc(maxpools, sizeof(unsigned int), GFP_KERNEL);
+ if (!m->to_pool)
+ goto fail;
+ m->pool_to = kcalloc(maxpools, sizeof(unsigned int), GFP_KERNEL);
+ if (!m->pool_to)
+ goto fail_free;
+
+ return 0;
+
+fail_free:
+ kfree(m->to_pool);
+fail:
+ return -ENOMEM;
+}
+
+/*
+ * Initialise the pool map for SVC_POOL_PERCPU mode.
+ * Returns number of pools or <0 on error.
+ */
+static int
+svc_pool_map_init_percpu(struct svc_pool_map *m)
+{
+ unsigned int maxpools = highest_possible_processor_id()+1;
+ unsigned int pidx = 0;
+ unsigned int cpu;
+ int err;
+
+ err = svc_pool_map_alloc_arrays(m, maxpools);
+ if (err)
+ return err;
+
+ for_each_online_cpu(cpu) {
+ BUG_ON(pidx > maxpools);
+ m->to_pool[cpu] = pidx;
+ m->pool_to[pidx] = cpu;
+ pidx++;
+ }
+ /* cpus brought online later all get mapped to pool0, sorry */
+
+ return pidx;
+};
+
+
+/*
+ * Initialise the pool map for SVC_POOL_PERNODE mode.
+ * Returns number of pools or <0 on error.
+ */
+static int
+svc_pool_map_init_pernode(struct svc_pool_map *m)
+{
+ unsigned int maxpools = highest_possible_node_id()+1;
+ unsigned int pidx = 0;
+ unsigned int node;
+ int err;
+
+ err = svc_pool_map_alloc_arrays(m, maxpools);
+ if (err)
+ return err;
+
+ for_each_node_with_cpus(node) {
+ /* some architectures (e.g. SN2) have cpuless nodes */
+ BUG_ON(pidx > maxpools);
+ m->to_pool[node] = pidx;
+ m->pool_to[pidx] = node;
+ pidx++;
+ }
+ /* nodes brought online later all get mapped to pool0, sorry */
+
+ return pidx;
+}
+
+
+/*
+ * Build the global map of cpus to pools and vice versa.
+ */
+static unsigned int
+svc_pool_map_init(void)
+{
+ struct svc_pool_map *m = &svc_pool_map;
+ int npools = -1;
+
+ if (m->mode != SVC_POOL_NONE)
+ return m->npools;
+
+ m->mode = svc_pool_map_choose_mode();
+
+ switch (m->mode) {
+ case SVC_POOL_PERCPU:
+ npools = svc_pool_map_init_percpu(m);
+ break;
+ case SVC_POOL_PERNODE:
+ npools = svc_pool_map_init_pernode(m);
+ break;
+ }
+
+ if (npools < 0) {
+ /* default, or memory allocation failure */
+ npools = 1;
+ m->mode = SVC_POOL_GLOBAL;
+ }
+ m->npools = npools;
+
+ return m->npools;
+}
+
+/*
+ * Set the current thread's cpus_allowed mask so that it
+ * will only run on cpus in the given pool.
+ *
+ * Returns 1 and fills in oldmask iff a cpumask was applied.
+ */
+static inline int
+svc_pool_map_set_cpumask(unsigned int pidx, cpumask_t *oldmask)
+{
+ struct svc_pool_map *m = &svc_pool_map;
+ unsigned int node; /* or cpu */
+
+ /*
+ * The caller checks for sv_nrpools > 1, which
+ * implies that we've been initialized and the
+ * map mode is not NONE.
+ */
+ BUG_ON(m->mode == SVC_POOL_NONE);
+
+ switch (m->mode)
+ {
+ default:
+ return 0;
+ case SVC_POOL_PERCPU:
+ node = m->pool_to[pidx];
+ *oldmask = current->cpus_allowed;
+ set_cpus_allowed(current, cpumask_of_cpu(node));
+ return 1;
+ case SVC_POOL_PERNODE:
+ node = m->pool_to[pidx];
+ *oldmask = current->cpus_allowed;
+ set_cpus_allowed(current, node_to_cpumask(node));
+ return 1;
+ }
+}
+
+/*
+ * Use the mapping mode to choose a pool for a given CPU.
+ * Used when enqueueing an incoming RPC. Always returns
+ * a non-NULL pool pointer.
+ */
+struct svc_pool *
+svc_pool_for_cpu(struct svc_serv *serv, int cpu)
+{
+ struct svc_pool_map *m = &svc_pool_map;
+ unsigned int pidx = 0;
+
+ /*
+ * SVC_POOL_NONE happens in a pure client when
+ * lockd is brought up, so silently treat it the
+ * same as SVC_POOL_GLOBAL.
+ */
+
+ switch (m->mode) {
+ case SVC_POOL_PERCPU:
+ pidx = m->to_pool[cpu];
+ break;
+ case SVC_POOL_PERNODE:
+ pidx = m->to_pool[cpu_to_node(cpu)];
+ break;
+ }
+ return &serv->sv_pools[pidx % serv->sv_nrpools];
+}
+
+
+/*
* Create an RPC service
*/
-struct svc_serv *
-svc_create(struct svc_program *prog, unsigned int bufsize)
+static struct svc_serv *
+__svc_create(struct svc_program *prog, unsigned int bufsize, int npools,
+ void (*shutdown)(struct svc_serv *serv))
{
struct svc_serv *serv;
int vers;
unsigned int xdrsize;
+ unsigned int i;
if (!(serv = kzalloc(sizeof(*serv), GFP_KERNEL)))
return NULL;
@@ -39,6 +283,7 @@ svc_create(struct svc_program *prog, unsigned int bufsize)
serv->sv_nrthreads = 1;
serv->sv_stats = prog->pg_stats;
serv->sv_bufsz = bufsize? bufsize : 4096;
+ serv->sv_shutdown = shutdown;
xdrsize = 0;
while (prog) {
prog->pg_lovers = prog->pg_nvers-1;
@@ -53,20 +298,68 @@ svc_create(struct svc_program *prog, unsigned int bufsize)
prog = prog->pg_next;
}
serv->sv_xdrsize = xdrsize;
- INIT_LIST_HEAD(&serv->sv_threads);
- INIT_LIST_HEAD(&serv->sv_sockets);
INIT_LIST_HEAD(&serv->sv_tempsocks);
INIT_LIST_HEAD(&serv->sv_permsocks);
+ init_timer(&serv->sv_temptimer);
spin_lock_init(&serv->sv_lock);
+ serv->sv_nrpools = npools;
+ serv->sv_pools =
+ kcalloc(sizeof(struct svc_pool), serv->sv_nrpools,
+ GFP_KERNEL);
+ if (!serv->sv_pools) {
+ kfree(serv);
+ return NULL;
+ }
+
+ for (i = 0; i < serv->sv_nrpools; i++) {
+ struct svc_pool *pool = &serv->sv_pools[i];
+
+ dprintk("initialising pool %u for %s\n",
+ i, serv->sv_name);
+
+ pool->sp_id = i;
+ INIT_LIST_HEAD(&pool->sp_threads);
+ INIT_LIST_HEAD(&pool->sp_sockets);
+ INIT_LIST_HEAD(&pool->sp_all_threads);
+ spin_lock_init(&pool->sp_lock);
+ }
+
+
/* Remove any stale portmap registrations */
svc_register(serv, 0, 0);
return serv;
}
+struct svc_serv *
+svc_create(struct svc_program *prog, unsigned int bufsize,
+ void (*shutdown)(struct svc_serv *serv))
+{
+ return __svc_create(prog, bufsize, /*npools*/1, shutdown);
+}
+
+struct svc_serv *
+svc_create_pooled(struct svc_program *prog, unsigned int bufsize,
+ void (*shutdown)(struct svc_serv *serv),
+ svc_thread_fn func, int sig, struct module *mod)
+{
+ struct svc_serv *serv;
+ unsigned int npools = svc_pool_map_init();
+
+ serv = __svc_create(prog, bufsize, npools, shutdown);
+
+ if (serv != NULL) {
+ serv->sv_function = func;
+ serv->sv_kill_signal = sig;
+ serv->sv_module = mod;
+ }
+
+ return serv;
+}
+
/*
- * Destroy an RPC service
+ * Destroy an RPC service. Should be called with the BKL held
*/
void
svc_destroy(struct svc_serv *serv)
@@ -85,12 +378,17 @@ svc_destroy(struct svc_serv *serv)
} else
printk("svc_destroy: no threads for serv=%p!\n", serv);
+ del_timer_sync(&serv->sv_temptimer);
+
while (!list_empty(&serv->sv_tempsocks)) {
svsk = list_entry(serv->sv_tempsocks.next,
struct svc_sock,
sk_list);
svc_delete_socket(svsk);
}
+ if (serv->sv_shutdown)
+ serv->sv_shutdown(serv);
+
while (!list_empty(&serv->sv_permsocks)) {
svsk = list_entry(serv->sv_permsocks.next,
struct svc_sock,
@@ -102,6 +400,7 @@ svc_destroy(struct svc_serv *serv)
/* Unregister service with the portmapper */
svc_register(serv, 0, 0);
+ kfree(serv->sv_pools);
kfree(serv);
}
@@ -150,13 +449,18 @@ svc_release_buffer(struct svc_rqst *rqstp)
}
/*
- * Create a server thread
+ * Create a thread in the given pool. Caller must hold BKL.
+ * On a NUMA or SMP machine, with a multi-pool serv, the thread
+ * will be restricted to run on the cpus belonging to the pool.
*/
-int
-svc_create_thread(svc_thread_fn func, struct svc_serv *serv)
+static int
+__svc_create_thread(svc_thread_fn func, struct svc_serv *serv,
+ struct svc_pool *pool)
{
struct svc_rqst *rqstp;
int error = -ENOMEM;
+ int have_oldmask = 0;
+ cpumask_t oldmask;
rqstp = kzalloc(sizeof(*rqstp), GFP_KERNEL);
if (!rqstp)
@@ -170,8 +474,21 @@ svc_create_thread(svc_thread_fn func, struct svc_serv *serv)
goto out_thread;
serv->sv_nrthreads++;
+ spin_lock_bh(&pool->sp_lock);
+ pool->sp_nrthreads++;
+ list_add(&rqstp->rq_all, &pool->sp_all_threads);
+ spin_unlock_bh(&pool->sp_lock);
rqstp->rq_server = serv;
+ rqstp->rq_pool = pool;
+
+ if (serv->sv_nrpools > 1)
+ have_oldmask = svc_pool_map_set_cpumask(pool->sp_id, &oldmask);
+
error = kernel_thread((int (*)(void *)) func, rqstp, 0);
+
+ if (have_oldmask)
+ set_cpus_allowed(current, oldmask);
+
if (error < 0)
goto out_thread;
svc_sock_update_bufs(serv);
@@ -185,17 +502,136 @@ out_thread:
}
/*
- * Destroy an RPC server thread
+ * Create a thread in the default pool. Caller must hold BKL.
+ */
+int
+svc_create_thread(svc_thread_fn func, struct svc_serv *serv)
+{
+ return __svc_create_thread(func, serv, &serv->sv_pools[0]);
+}
+
+/*
+ * Choose a pool in which to create a new thread, for svc_set_num_threads
+ */
+static inline struct svc_pool *
+choose_pool(struct svc_serv *serv, struct svc_pool *pool, unsigned int *state)
+{
+ if (pool != NULL)
+ return pool;
+
+ return &serv->sv_pools[(*state)++ % serv->sv_nrpools];
+}
+
+/*
+ * Choose a thread to kill, for svc_set_num_threads
+ */
+static inline struct task_struct *
+choose_victim(struct svc_serv *serv, struct svc_pool *pool, unsigned int *state)
+{
+ unsigned int i;
+ struct task_struct *task = NULL;
+
+ if (pool != NULL) {
+ spin_lock_bh(&pool->sp_lock);
+ } else {
+ /* choose a pool in round-robin fashion */
+ for (i = 0; i < serv->sv_nrpools; i++) {
+ pool = &serv->sv_pools[--(*state) % serv->sv_nrpools];
+ spin_lock_bh(&pool->sp_lock);
+ if (!list_empty(&pool->sp_all_threads))
+ goto found_pool;
+ spin_unlock_bh(&pool->sp_lock);
+ }
+ return NULL;
+ }
+
+found_pool:
+ if (!list_empty(&pool->sp_all_threads)) {
+ struct svc_rqst *rqstp;
+
+ /*
+ * Remove from the pool->sp_all_threads list
+ * so we don't try to kill it again.
+ */
+ rqstp = list_entry(pool->sp_all_threads.next, struct svc_rqst, rq_all);
+ list_del_init(&rqstp->rq_all);
+ task = rqstp->rq_task;
+ }
+ spin_unlock_bh(&pool->sp_lock);
+
+ return task;
+}
+
+/*
+ * Create or destroy enough new threads to make the number
+ * of threads the given number. If `pool' is non-NULL, applies
+ * only to threads in that pool, otherwise round-robins between
+ * all pools. Must be called with a svc_get() reference and
+ * the BKL held.
+ *
+ * Destroying threads relies on the service threads filling in
+ * rqstp->rq_task, which only the nfs ones do. Assumes the serv
+ * has been created using svc_create_pooled().
+ *
+ * Based on code that used to be in nfsd_svc() but tweaked
+ * to be pool-aware.
+ */
+int
+svc_set_num_threads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
+{
+ struct task_struct *victim;
+ int error = 0;
+ unsigned int state = serv->sv_nrthreads-1;
+
+ if (pool == NULL) {
+ /* The -1 assumes caller has done a svc_get() */
+ nrservs -= (serv->sv_nrthreads-1);
+ } else {
+ spin_lock_bh(&pool->sp_lock);
+ nrservs -= pool->sp_nrthreads;
+ spin_unlock_bh(&pool->sp_lock);
+ }
+
+ /* create new threads */
+ while (nrservs > 0) {
+ nrservs--;
+ __module_get(serv->sv_module);
+ error = __svc_create_thread(serv->sv_function, serv,
+ choose_pool(serv, pool, &state));
+ if (error < 0) {
+ module_put(serv->sv_module);
+ break;
+ }
+ }
+ /* destroy old threads */
+ while (nrservs < 0 &&
+ (victim = choose_victim(serv, pool, &state)) != NULL) {
+ send_sig(serv->sv_kill_signal, victim, 1);
+ nrservs++;
+ }
+
+ return error;
+}
+
+/*
+ * Called from a server thread as it's exiting. Caller must hold BKL.
*/
void
svc_exit_thread(struct svc_rqst *rqstp)
{
struct svc_serv *serv = rqstp->rq_server;
+ struct svc_pool *pool = rqstp->rq_pool;
svc_release_buffer(rqstp);
kfree(rqstp->rq_resp);
kfree(rqstp->rq_argp);
kfree(rqstp->rq_auth_data);
+
+ spin_lock_bh(&pool->sp_lock);
+ pool->sp_nrthreads--;
+ list_del(&rqstp->rq_all);
+ spin_unlock_bh(&pool->sp_lock);
+
kfree(rqstp);
/* Release the server */
@@ -248,13 +684,14 @@ svc_register(struct svc_serv *serv, int proto, unsigned short port)
* Process the RPC request.
*/
int
-svc_process(struct svc_serv *serv, struct svc_rqst *rqstp)
+svc_process(struct svc_rqst *rqstp)
{
struct svc_program *progp;
struct svc_version *versp = NULL; /* compiler food */
struct svc_procedure *procp = NULL;
struct kvec * argv = &rqstp->rq_arg.head[0];
struct kvec * resv = &rqstp->rq_res.head[0];
+ struct svc_serv *serv = rqstp->rq_server;
kxdrproc_t xdr;
__be32 *statp;
u32 dir, prog, vers, proc;