/* flow.c: Generic flow cache. * * Copyright (C) 2003 Alexey N. Kuznetsov (kuznet@ms2.inr.ac.ru) * Copyright (C) 2003 David S. Miller (davem@redhat.com) */ #include <linux/kernel.h>#include <linux/module.h>#include <linux/list.h>#include <linux/jhash.h>#include <linux/interrupt.h>#include <linux/mm.h>#include <linux/random.h>#include <linux/init.h>#include <linux/slab.h>#include <linux/smp.h>#include <linux/completion.h>#include <linux/percpu.h>#include <linux/bitops.h>#include <linux/notifier.h>#include <linux/cpu.h>#include <linux/cpumask.h>#include <linux/mutex.h>#include <net/flow.h>#include <linux/atomic.h>#include <linux/security.h>#include <net/net_namespace.h> struct flow_cache_entry { union { struct hlist_node hlist; struct list_head gc_list; } u; struct net *net; u16 family; u8 dir; u32 genid; struct flowi key; struct flow_cache_object *object;}; struct flow_flush_info { struct flow_cache *cache; atomic_t cpuleft; struct completion completion;}; static struct kmem_cache *flow_cachep __read_mostly; #define flow_cache_hash_size(cache) (1U << (cache)->hash_shift)#define FLOW_HASH_RND_PERIOD (10 * 60 * HZ) static void flow_cache_new_hashrnd(unsigned long arg){ struct flow_cache *fc = (void *) arg; int i; for_each_possible_cpu(i) per_cpu_ptr(fc->percpu, i)->hash_rnd_recalc = 1; fc->rnd_timer.expires = jiffies + FLOW_HASH_RND_PERIOD; add_timer(&fc->rnd_timer);} static int flow_entry_valid(struct flow_cache_entry *fle, struct netns_xfrm *xfrm){ if (atomic_read(&xfrm->flow_cache_genid) != fle->genid) return 0; if (fle->object && !fle->object->ops->check(fle->object)) return 0; return 1;} static void flow_entry_kill(struct flow_cache_entry *fle, struct netns_xfrm *xfrm){ if (fle->object) fle->object->ops->delete(fle->object); kmem_cache_free(flow_cachep, fle);} static void flow_cache_gc_task(struct work_struct *work){ struct list_head gc_list; struct flow_cache_entry *fce, *n; struct netns_xfrm *xfrm = container_of(work, struct netns_xfrm, flow_cache_gc_work); INIT_LIST_HEAD(&gc_list); spin_lock_bh(&xfrm->flow_cache_gc_lock); list_splice_tail_init(&xfrm->flow_cache_gc_list, &gc_list); spin_unlock_bh(&xfrm->flow_cache_gc_lock); list_for_each_entry_safe(fce, n, &gc_list, u.gc_list) { flow_entry_kill(fce, xfrm); atomic_dec(&xfrm->flow_cache_gc_count); }} static void flow_cache_queue_garbage(struct flow_cache_percpu *fcp, unsigned int deleted, struct list_head *gc_list, struct netns_xfrm *xfrm){ if (deleted) { atomic_add(deleted, &xfrm->flow_cache_gc_count); fcp->hash_count -= deleted; spin_lock_bh(&xfrm->flow_cache_gc_lock); list_splice_tail(gc_list, &xfrm->flow_cache_gc_list); spin_unlock_bh(&xfrm->flow_cache_gc_lock); schedule_work(&xfrm->flow_cache_gc_work); }} static void __flow_cache_shrink(struct flow_cache *fc, struct flow_cache_percpu *fcp, unsigned int shrink_to){ struct flow_cache_entry *fle; struct hlist_node *tmp; LIST_HEAD(gc_list); unsigned int deleted = 0; struct netns_xfrm *xfrm = container_of(fc, struct netns_xfrm, flow_cache_global); unsigned int i; for (i = 0; i < flow_cache_hash_size(fc); i++) { unsigned int saved = 0; hlist_for_each_entry_safe(fle, tmp, &fcp->hash_table[i], u.hlist) { if (saved < shrink_to && flow_entry_valid(fle, xfrm)) { saved++; } else { deleted++; hlist_del(&fle->u.hlist); list_add_tail(&fle->u.gc_list, &gc_list); } } } flow_cache_queue_garbage(fcp, deleted, &gc_list, xfrm);} static void flow_cache_shrink(struct flow_cache *fc, struct flow_cache_percpu *fcp){ unsigned int shrink_to = fc->low_watermark / flow_cache_hash_size(fc); __flow_cache_shrink(fc, fcp, shrink_to);} static void flow_new_hash_rnd(struct flow_cache *fc, struct flow_cache_percpu *fcp){ get_random_bytes(&fcp->hash_rnd, sizeof(u32)); fcp->hash_rnd_recalc = 0; __flow_cache_shrink(fc, fcp, 0);} static u32 flow_hash_code(struct flow_cache *fc, struct flow_cache_percpu *fcp, const struct flowi *key, unsigned int keysize){ const u32 *k = (const u32 *) key; const u32 length = keysize * sizeof(flow_compare_t) / sizeof(u32); return jhash2(k, length, fcp->hash_rnd) & (flow_cache_hash_size(fc) - 1);} /* I hear what you're saying, use memcmp. But memcmp cannot make * important assumptions that we can here, such as alignment. */static int flow_key_compare(const struct flowi *key1, const struct flowi *key2, unsigned int keysize){ const flow_compare_t *k1, *k1_lim, *k2; k1 = (const flow_compare_t *) key1; k1_lim = k1 + keysize; k2 = (const flow_compare_t *) key2; do { if (*k1++ != *k2++) return 1; } while (k1 < k1_lim); return 0;} struct flow_cache_object *flow_cache_lookup(struct net *net, const struct flowi *key, u16 family, u8 dir, flow_resolve_t resolver, void *ctx){ struct flow_cache *fc = &net->xfrm.flow_cache_global; struct flow_cache_percpu *fcp; struct flow_cache_entry *fle, *tfle; struct flow_cache_object *flo; unsigned int keysize; unsigned int hash; local_bh_disable(); fcp = this_cpu_ptr(fc->percpu); fle = NULL; flo = NULL; keysize = flow_key_size(family); if (!keysize) goto nocache; /* Packet really early in init? Making flow_cache_init a * pre-smp initcall would solve this. --RR */ if (!fcp->hash_table) goto nocache; if (fcp->hash_rnd_recalc) flow_new_hash_rnd(fc, fcp); hash = flow_hash_code(fc, fcp, key, keysize); hlist_for_each_entry(tfle, &fcp->hash_table[hash], u.hlist) { if (tfle->net == net && tfle->family == family && tfle->dir == dir && flow_key_compare(key, &tfle->key, keysize) == 0) { fle = tfle; break; } } if (unlikely(!fle)) { if (fcp->hash_count > fc->high_watermark) flow_cache_shrink(fc, fcp); if (atomic_read(&net->xfrm.flow_cache_gc_count) > 2 * num_online_cpus() * fc->high_watermark) { flo = ERR_PTR(-ENOBUFS); goto ret_object; } fle = kmem_cache_alloc(flow_cachep, GFP_ATOMIC); if (fle) { fle->net = net; fle->family = family; fle->dir = dir; memcpy(&fle->key, key, keysize * sizeof(flow_compare_t)); fle->object = NULL; hlist_add_head(&fle->u.hlist, &fcp->hash_table[hash]); fcp->hash_count++; } } else if (likely(fle->genid == atomic_read(&net->xfrm.flow_cache_genid))) { flo = fle->object; if (!flo) goto ret_object; flo = flo->ops->get(flo); if (flo) goto ret_object; } else if (fle->object) { flo = fle->object; flo->ops->delete(flo); fle->object = NULL; } nocache: flo = NULL; if (fle) { flo = fle->object; fle->object = NULL; } flo = resolver(net, key, family, dir, flo, ctx); if (fle) { fle->genid = atomic_read(&net->xfrm.flow_cache_genid); if (!IS_ERR(flo)) fle->object = flo; else fle->genid--; } else { if (!IS_ERR_OR_NULL(flo)) flo->ops->delete(flo); }ret_object: local_bh_enable(); return flo;}EXPORT_SYMBOL(flow_cache_lookup); static void flow_cache_flush_tasklet(unsigned long data){ struct flow_flush_info *info = (void *)data; struct flow_cache *fc = info->cache; struct flow_cache_percpu *fcp; struct flow_cache_entry *fle; struct hlist_node *tmp; LIST_HEAD(gc_list); unsigned int deleted = 0; struct netns_xfrm *xfrm = container_of(fc, struct netns_xfrm, flow_cache_global); unsigned int i; fcp = this_cpu_ptr(fc->percpu); for (i = 0; i < flow_cache_hash_size(fc); i++) { hlist_for_each_entry_safe(fle, tmp, &fcp->hash_table[i], u.hlist) { if (flow_entry_valid(fle, xfrm)) continue; deleted++; hlist_del(&fle->u.hlist); list_add_tail(&fle->u.gc_list, &gc_list); } } flow_cache_queue_garbage(fcp, deleted, &gc_list, xfrm); if (atomic_dec_and_test(&info->cpuleft)) complete(&info->completion);} /* * Return whether a cpu needs flushing. Conservatively, we assume * the presence of any entries means the core may require flushing, * since the flow_cache_ops.check() function may assume it's running * on the same core as the per-cpu cache component. */static int flow_cache_percpu_empty(struct flow_cache *fc, int cpu){ struct flow_cache_percpu *fcp; unsigned int i; fcp = per_cpu_ptr(fc->percpu, cpu); for (i = 0; i < flow_cache_hash_size(fc); i++) if (!hlist_empty(&fcp->hash_table[i])) return 0; return 1;} static void flow_cache_flush_per_cpu(void *data){ struct flow_flush_info *info = data; struct tasklet_struct *tasklet; tasklet = &this_cpu_ptr(info->cache->percpu)->flush_tasklet; tasklet->data = (unsigned long)info; tasklet_schedule(tasklet);} void flow_cache_flush(struct net *net){ struct flow_flush_info info; cpumask_var_t mask; int i, self; /* Track which cpus need flushing to avoid disturbing all cores. */ if (!alloc_cpumask_var(&mask, GFP_KERNEL)) return; cpumask_clear(mask); /* Don't want cpus going down or up during this. */ get_online_cpus(); mutex_lock(&net->xfrm.flow_flush_sem); info.cache = &net->xfrm.flow_cache_global; for_each_online_cpu(i) if (!flow_cache_percpu_empty(info.cache, i)) cpumask_set_cpu(i, mask); atomic_set(&info.cpuleft, cpumask_weight(mask)); if (atomic_read(&info.cpuleft) == 0) goto done; init_completion(&info.completion); local_bh_disable(); self = cpumask_test_and_clear_cpu(smp_processor_id(), mask); on_each_cpu_mask(mask, flow_cache_flush_per_cpu, &info, 0); if (self) flow_cache_flush_tasklet((unsigned long)&info); local_bh_enable(); wait_for_completion(&info.completion); done: mutex_unlock(&net->xfrm.flow_flush_sem); put_online_cpus(); free_cpumask_var(mask);} static void flow_cache_flush_task(struct work_struct *work){ struct netns_xfrm *xfrm = container_of(work, struct netns_xfrm, flow_cache_flush_work); struct net *net = container_of(xfrm, struct net, xfrm); flow_cache_flush(net);} void flow_cache_flush_deferred(struct net *net){ schedule_work(&net->xfrm.flow_cache_flush_work);} static int flow_cache_cpu_prepare(struct flow_cache *fc, int cpu){ struct flow_cache_percpu *fcp = per_cpu_ptr(fc->percpu, cpu); unsigned int sz = sizeof(struct hlist_head) * flow_cache_hash_size(fc); if (!fcp->hash_table) { fcp->hash_table = kzalloc_node(sz, GFP_KERNEL, cpu_to_node(cpu)); if (!fcp->hash_table) { pr_err("NET: failed to allocate flow cache sz %u\n", sz); return -ENOMEM; } fcp->hash_rnd_recalc = 1; fcp->hash_count = 0; tasklet_init(&fcp->flush_tasklet, flow_cache_flush_tasklet, 0); } return 0;} static int flow_cache_cpu_up_prep(unsigned int cpu, struct hlist_node *node){ struct flow_cache *fc = hlist_entry_safe(node, struct flow_cache, node); return flow_cache_cpu_prepare(fc, cpu);} static int flow_cache_cpu_dead(unsigned int cpu, struct hlist_node *node){ struct flow_cache *fc = hlist_entry_safe(node, struct flow_cache, node); struct flow_cache_percpu *fcp = per_cpu_ptr(fc->percpu, cpu); __flow_cache_shrink(fc, fcp, 0); return 0;} int flow_cache_init(struct net *net){ int i; struct flow_cache *fc = &net->xfrm.flow_cache_global; if (!flow_cachep) flow_cachep = kmem_cache_create("flow_cache", sizeof(struct flow_cache_entry), 0, SLAB_PANIC, NULL); spin_lock_init(&net->xfrm.flow_cache_gc_lock); INIT_LIST_HEAD(&net->xfrm.flow_cache_gc_list); INIT_WORK(&net->xfrm.flow_cache_gc_work, flow_cache_gc_task); INIT_WORK(&net->xfrm.flow_cache_flush_work, flow_cache_flush_task); mutex_init(&net->xfrm.flow_flush_sem); atomic_set(&net->xfrm.flow_cache_gc_count, 0); fc->hash_shift = 10; fc->low_watermark = 2 * flow_cache_hash_size(fc); fc->high_watermark = 4 * flow_cache_hash_size(fc); fc->percpu = alloc_percpu(struct flow_cache_percpu); if (!fc->percpu) return -ENOMEM; if (cpuhp_state_add_instance(CPUHP_NET_FLOW_PREPARE, &fc->node)) goto err; setup_timer(&fc->rnd_timer, flow_cache_new_hashrnd, (unsigned long) fc); fc->rnd_timer.expires = jiffies + FLOW_HASH_RND_PERIOD; add_timer(&fc->rnd_timer); return 0; err: for_each_possible_cpu(i) { struct flow_cache_percpu *fcp = per_cpu_ptr(fc->percpu, i); kfree(fcp->hash_table); fcp->hash_table = NULL; } free_percpu(fc->percpu); fc->percpu = NULL; return -ENOMEM;}EXPORT_SYMBOL(flow_cache_init); void flow_cache_fini(struct net *net){ int i; struct flow_cache *fc = &net->xfrm.flow_cache_global; del_timer_sync(&fc->rnd_timer); cpuhp_state_remove_instance_nocalls(CPUHP_NET_FLOW_PREPARE, &fc->node); for_each_possible_cpu(i) { struct flow_cache_percpu *fcp = per_cpu_ptr(fc->percpu, i); kfree(fcp->hash_table); fcp->hash_table = NULL; }Lines 1–500 of 516. Load more
/* flow.c: Generic flow cache. * * Copyright (C) 2003 Alexey N. Kuznetsov (kuznet@ms2.inr.ac.ru) * Copyright (C) 2003 David S. Miller (davem@redhat.com) */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/list.h> #include <linux/jhash.h> #include <linux/interrupt.h> #include <linux/mm.h> #include <linux/random.h> #include <linux/init.h> #include <linux/slab.h> #include <linux/smp.h> #include <linux/completion.h> #include <linux/percpu.h> #include <linux/bitops.h> #include <linux/notifier.h> #include <linux/cpu.h> #include <linux/cpumask.h> #include <linux/mutex.h> #include <net/flow.h> #include <linux/atomic.h> #include <linux/security.h> #include <net/net_namespace.h> struct flow_cache_entry { union { struct hlist_node hlist; struct list_head gc_list; } u; struct net *net; u16 family; u8 dir; u32 genid; struct flowi key; struct flow_cache_object *object; }; struct flow_flush_info { struct flow_cache *cache; atomic_t cpuleft; struct completion completion; }; static struct kmem_cache *flow_cachep __read_mostly; #define flow_cache_hash_size(cache) (1U << (cache)->hash_shift) #define FLOW_HASH_RND_PERIOD (10 * 60 * HZ) static void flow_cache_new_hashrnd(unsigned long arg) { struct flow_cache *fc = (void *) arg; int i; for_each_possible_cpu(i) per_cpu_ptr(fc->percpu, i)->hash_rnd_recalc = 1; fc->rnd_timer.expires = jiffies + FLOW_HASH_RND_PERIOD; add_timer(&fc->rnd_timer); } static int flow_entry_valid(struct flow_cache_entry *fle, struct netns_xfrm *xfrm) { if (atomic_read(&xfrm->flow_cache_genid) != fle->genid) return 0; if (fle->object && !fle->object->ops->check(fle->object)) return 0; return 1; } static void flow_entry_kill(struct flow_cache_entry *fle, struct netns_xfrm *xfrm) { if (fle->object) fle->object->ops->delete(fle->object); kmem_cache_free(flow_cachep, fle); } static void flow_cache_gc_task(struct work_struct *work) { struct list_head gc_list; struct flow_cache_entry *fce, *n; struct netns_xfrm *xfrm = container_of(work, struct netns_xfrm, flow_cache_gc_work); INIT_LIST_HEAD(&gc_list); spin_lock_bh(&xfrm->flow_cache_gc_lock); list_splice_tail_init(&xfrm->flow_cache_gc_list, &gc_list); spin_unlock_bh(&xfrm->flow_cache_gc_lock); list_for_each_entry_safe(fce, n, &gc_list, u.gc_list) { flow_entry_kill(fce, xfrm); atomic_dec(&xfrm->flow_cache_gc_count); } } static void flow_cache_queue_garbage(struct flow_cache_percpu *fcp, unsigned int deleted, struct list_head *gc_list, struct netns_xfrm *xfrm) { if (deleted) { atomic_add(deleted, &xfrm->flow_cache_gc_count); fcp->hash_count -= deleted; spin_lock_bh(&xfrm->flow_cache_gc_lock); list_splice_tail(gc_list, &xfrm->flow_cache_gc_list); spin_unlock_bh(&xfrm->flow_cache_gc_lock); schedule_work(&xfrm->flow_cache_gc_work); } } static void __flow_cache_shrink(struct flow_cache *fc, struct flow_cache_percpu *fcp, unsigned int shrink_to) { struct flow_cache_entry *fle; struct hlist_node *tmp; LIST_HEAD(gc_list); unsigned int deleted = 0; struct netns_xfrm *xfrm = container_of(fc, struct netns_xfrm, flow_cache_global); unsigned int i; for (i = 0; i < flow_cache_hash_size(fc); i++) { unsigned int saved = 0; hlist_for_each_entry_safe(fle, tmp, &fcp->hash_table[i], u.hlist) { if (saved < shrink_to && flow_entry_valid(fle, xfrm)) { saved++; } else { deleted++; hlist_del(&fle->u.hlist); list_add_tail(&fle->u.gc_list, &gc_list); } } } flow_cache_queue_garbage(fcp, deleted, &gc_list, xfrm); } static void flow_cache_shrink(struct flow_cache *fc, struct flow_cache_percpu *fcp) { unsigned int shrink_to = fc->low_watermark / flow_cache_hash_size(fc); __flow_cache_shrink(fc, fcp, shrink_to); } static void flow_new_hash_rnd(struct flow_cache *fc, struct flow_cache_percpu *fcp) { get_random_bytes(&fcp->hash_rnd, sizeof(u32)); fcp->hash_rnd_recalc = 0; __flow_cache_shrink(fc, fcp, 0); } static u32 flow_hash_code(struct flow_cache *fc, struct flow_cache_percpu *fcp, const struct flowi *key, unsigned int keysize) { const u32 *k = (const u32 *) key; const u32 length = keysize * sizeof(flow_compare_t) / sizeof(u32); return jhash2(k, length, fcp->hash_rnd) & (flow_cache_hash_size(fc) - 1); } /* I hear what you're saying, use memcmp. But memcmp cannot make * important assumptions that we can here, such as alignment. */ static int flow_key_compare(const struct flowi *key1, const struct flowi *key2, unsigned int keysize) { const flow_compare_t *k1, *k1_lim, *k2; k1 = (const flow_compare_t *) key1; k1_lim = k1 + keysize; k2 = (const flow_compare_t *) key2; do { if (*k1++ != *k2++) return 1; } while (k1 < k1_lim); return 0; } struct flow_cache_object * flow_cache_lookup(struct net *net, const struct flowi *key, u16 family, u8 dir, flow_resolve_t resolver, void *ctx) { struct flow_cache *fc = &net->xfrm.flow_cache_global; struct flow_cache_percpu *fcp; struct flow_cache_entry *fle, *tfle; struct flow_cache_object *flo; unsigned int keysize; unsigned int hash; local_bh_disable(); fcp = this_cpu_ptr(fc->percpu); fle = NULL; flo = NULL; keysize = flow_key_size(family); if (!keysize) goto nocache; /* Packet really early in init? Making flow_cache_init a * pre-smp initcall would solve this. --RR */ if (!fcp->hash_table) goto nocache; if (fcp->hash_rnd_recalc) flow_new_hash_rnd(fc, fcp); hash = flow_hash_code(fc, fcp, key, keysize); hlist_for_each_entry(tfle, &fcp->hash_table[hash], u.hlist) { if (tfle->net == net && tfle->family == family && tfle->dir == dir && flow_key_compare(key, &tfle->key, keysize) == 0) { fle = tfle; break; } } if (unlikely(!fle)) { if (fcp->hash_count > fc->high_watermark) flow_cache_shrink(fc, fcp); if (atomic_read(&net->xfrm.flow_cache_gc_count) > 2 * num_online_cpus() * fc->high_watermark) { flo = ERR_PTR(-ENOBUFS); goto ret_object; } fle = kmem_cache_alloc(flow_cachep, GFP_ATOMIC); if (fle) { fle->net = net; fle->family = family; fle->dir = dir; memcpy(&fle->key, key, keysize * sizeof(flow_compare_t)); fle->object = NULL; hlist_add_head(&fle->u.hlist, &fcp->hash_table[hash]); fcp->hash_count++; } } else if (likely(fle->genid == atomic_read(&net->xfrm.flow_cache_genid))) { flo = fle->object; if (!flo) goto ret_object; flo = flo->ops->get(flo); if (flo) goto ret_object; } else if (fle->object) { flo = fle->object; flo->ops->delete(flo); fle->object = NULL; } nocache: flo = NULL; if (fle) { flo = fle->object; fle->object = NULL; } flo = resolver(net, key, family, dir, flo, ctx); if (fle) { fle->genid = atomic_read(&net->xfrm.flow_cache_genid); if (!IS_ERR(flo)) fle->object = flo; else fle->genid--; } else { if (!IS_ERR_OR_NULL(flo)) flo->ops->delete(flo); } ret_object: local_bh_enable(); return flo; } EXPORT_SYMBOL(flow_cache_lookup); static void flow_cache_flush_tasklet(unsigned long data) { struct flow_flush_info *info = (void *)data; struct flow_cache *fc = info->cache; struct flow_cache_percpu *fcp; struct flow_cache_entry *fle; struct hlist_node *tmp; LIST_HEAD(gc_list); unsigned int deleted = 0; struct netns_xfrm *xfrm = container_of(fc, struct netns_xfrm, flow_cache_global); unsigned int i; fcp = this_cpu_ptr(fc->percpu); for (i = 0; i < flow_cache_hash_size(fc); i++) { hlist_for_each_entry_safe(fle, tmp, &fcp->hash_table[i], u.hlist) { if (flow_entry_valid(fle, xfrm)) continue; deleted++; hlist_del(&fle->u.hlist); list_add_tail(&fle->u.gc_list, &gc_list); } } flow_cache_queue_garbage(fcp, deleted, &gc_list, xfrm); if (atomic_dec_and_test(&info->cpuleft)) complete(&info->completion); } /* * Return whether a cpu needs flushing. Conservatively, we assume * the presence of any entries means the core may require flushing, * since the flow_cache_ops.check() function may assume it's running * on the same core as the per-cpu cache component. */ static int flow_cache_percpu_empty(struct flow_cache *fc, int cpu) { struct flow_cache_percpu *fcp; unsigned int i; fcp = per_cpu_ptr(fc->percpu, cpu); for (i = 0; i < flow_cache_hash_size(fc); i++) if (!hlist_empty(&fcp->hash_table[i])) return 0; return 1; } static void flow_cache_flush_per_cpu(void *data) { struct flow_flush_info *info = data; struct tasklet_struct *tasklet; tasklet = &this_cpu_ptr(info->cache->percpu)->flush_tasklet; tasklet->data = (unsigned long)info; tasklet_schedule(tasklet); } void flow_cache_flush(struct net *net) { struct flow_flush_info info; cpumask_var_t mask; int i, self; /* Track which cpus need flushing to avoid disturbing all cores. */ if (!alloc_cpumask_var(&mask, GFP_KERNEL)) return; cpumask_clear(mask); /* Don't want cpus going down or up during this. */ get_online_cpus(); mutex_lock(&net->xfrm.flow_flush_sem); info.cache = &net->xfrm.flow_cache_global; for_each_online_cpu(i) if (!flow_cache_percpu_empty(info.cache, i)) cpumask_set_cpu(i, mask); atomic_set(&info.cpuleft, cpumask_weight(mask)); if (atomic_read(&info.cpuleft) == 0) goto done; init_completion(&info.completion); local_bh_disable(); self = cpumask_test_and_clear_cpu(smp_processor_id(), mask); on_each_cpu_mask(mask, flow_cache_flush_per_cpu, &info, 0); if (self) flow_cache_flush_tasklet((unsigned long)&info); local_bh_enable(); wait_for_completion(&info.completion); done: mutex_unlock(&net->xfrm.flow_flush_sem); put_online_cpus(); free_cpumask_var(mask); } static void flow_cache_flush_task(struct work_struct *work) { struct netns_xfrm *xfrm = container_of(work, struct netns_xfrm, flow_cache_flush_work); struct net *net = container_of(xfrm, struct net, xfrm); flow_cache_flush(net); } void flow_cache_flush_deferred(struct net *net) { schedule_work(&net->xfrm.flow_cache_flush_work); } static int flow_cache_cpu_prepare(struct flow_cache *fc, int cpu) { struct flow_cache_percpu *fcp = per_cpu_ptr(fc->percpu, cpu); unsigned int sz = sizeof(struct hlist_head) * flow_cache_hash_size(fc); if (!fcp->hash_table) { fcp->hash_table = kzalloc_node(sz, GFP_KERNEL, cpu_to_node(cpu)); if (!fcp->hash_table) { pr_err("NET: failed to allocate flow cache sz %u\n", sz); return -ENOMEM; } fcp->hash_rnd_recalc = 1; fcp->hash_count = 0; tasklet_init(&fcp->flush_tasklet, flow_cache_flush_tasklet, 0); } return 0; } static int flow_cache_cpu_up_prep(unsigned int cpu, struct hlist_node *node) { struct flow_cache *fc = hlist_entry_safe(node, struct flow_cache, node); return flow_cache_cpu_prepare(fc, cpu); } static int flow_cache_cpu_dead(unsigned int cpu, struct hlist_node *node) { struct flow_cache *fc = hlist_entry_safe(node, struct flow_cache, node); struct flow_cache_percpu *fcp = per_cpu_ptr(fc->percpu, cpu); __flow_cache_shrink(fc, fcp, 0); return 0; } int flow_cache_init(struct net *net) { int i; struct flow_cache *fc = &net->xfrm.flow_cache_global; if (!flow_cachep) flow_cachep = kmem_cache_create("flow_cache", sizeof(struct flow_cache_entry), 0, SLAB_PANIC, NULL); spin_lock_init(&net->xfrm.flow_cache_gc_lock); INIT_LIST_HEAD(&net->xfrm.flow_cache_gc_list); INIT_WORK(&net->xfrm.flow_cache_gc_work, flow_cache_gc_task); INIT_WORK(&net->xfrm.flow_cache_flush_work, flow_cache_flush_task); mutex_init(&net->xfrm.flow_flush_sem); atomic_set(&net->xfrm.flow_cache_gc_count, 0); fc->hash_shift = 10; fc->low_watermark = 2 * flow_cache_hash_size(fc); fc->high_watermark = 4 * flow_cache_hash_size(fc); fc->percpu = alloc_percpu(struct flow_cache_percpu); if (!fc->percpu) return -ENOMEM; if (cpuhp_state_add_instance(CPUHP_NET_FLOW_PREPARE, &fc->node)) goto err; setup_timer(&fc->rnd_timer, flow_cache_new_hashrnd, (unsigned long) fc); fc->rnd_timer.expires = jiffies + FLOW_HASH_RND_PERIOD; add_timer(&fc->rnd_timer); return 0; err: for_each_possible_cpu(i) { struct flow_cache_percpu *fcp = per_cpu_ptr(fc->percpu, i); kfree(fcp->hash_table); fcp->hash_table = NULL; } free_percpu(fc->percpu); fc->percpu = NULL; return -ENOMEM; } EXPORT_SYMBOL(flow_cache_init); void flow_cache_fini(struct net *net) { int i; struct flow_cache *fc = &net->xfrm.flow_cache_global; del_timer_sync(&fc->rnd_timer); cpuhp_state_remove_instance_nocalls(CPUHP_NET_FLOW_PREPARE, &fc->node); for_each_possible_cpu(i) { struct flow_cache_percpu *fcp = per_cpu_ptr(fc->percpu, i); kfree(fcp->hash_table); fcp->hash_table = NULL; }