diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/sunrpc/svc.c | 255 | ||||
| -rw-r--r-- | net/sunrpc/svcsock.c | 7 |
2 files changed, 260 insertions, 2 deletions
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index 8c75eec..a99e67b 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> @@ -25,6 +29,242 @@ #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 */ static struct svc_serv * @@ -105,8 +345,9 @@ svc_create_pooled(struct svc_program *prog, unsigned int bufsize, 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*/1, shutdown); + serv = __svc_create(prog, bufsize, npools, shutdown); if (serv != NULL) { serv->sv_function = func; @@ -209,6 +450,8 @@ svc_release_buffer(struct svc_rqst *rqstp) /* * 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. */ static int __svc_create_thread(svc_thread_fn func, struct svc_serv *serv, @@ -216,6 +459,8 @@ __svc_create_thread(svc_thread_fn func, struct svc_serv *serv, { struct svc_rqst *rqstp; int error = -ENOMEM; + int have_oldmask = 0; + cpumask_t oldmask; rqstp = kzalloc(sizeof(*rqstp), GFP_KERNEL); if (!rqstp) @@ -235,7 +480,15 @@ __svc_create_thread(svc_thread_fn func, struct svc_serv *serv, 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); diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index b78659a..cba85d1 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -151,8 +151,9 @@ static void svc_sock_enqueue(struct svc_sock *svsk) { struct svc_serv *serv = svsk->sk_server; - struct svc_pool *pool = &serv->sv_pools[0]; + struct svc_pool *pool; struct svc_rqst *rqstp; + int cpu; if (!(svsk->sk_flags & ( (1<<SK_CONN)|(1<<SK_DATA)|(1<<SK_CLOSE)|(1<<SK_DEFERRED)) )) @@ -160,6 +161,10 @@ svc_sock_enqueue(struct svc_sock *svsk) if (test_bit(SK_DEAD, &svsk->sk_flags)) return; + cpu = get_cpu(); + pool = svc_pool_for_cpu(svsk->sk_server, cpu); + put_cpu(); + spin_lock_bh(&pool->sp_lock); if (!list_empty(&pool->sp_threads) && |
