From 83b6b1f5d13414d0cb5c4f0a567a6aec0af073bd Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 10 Sep 2010 07:00:25 +0000 Subject: [PATCH] flow: better memory management Allocate hash tables for every online cpus, not every possible ones. NUMA aware allocations. Dont use a full page on arches where PAGE_SIZE > 1024*sizeof(void *) misc: __percpu , __read_mostly, __cpuinit annotations flow_compare_t is just an "unsigned long" Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/core/flow.c | 78 +++++++++++++++++++++++++++++++-------------------------- 1 file changed, 42 insertions(+), 36 deletions(-) diff --git a/net/core/flow.c b/net/core/flow.c index f67dcbf..b143b86 100644 --- a/net/core/flow.c +++ b/net/core/flow.c @@ -53,8 +53,7 @@ struct flow_flush_info { struct flow_cache { u32 hash_shift; - unsigned long order; - struct flow_cache_percpu *percpu; + struct flow_cache_percpu __percpu *percpu; struct notifier_block hotcpu_notifier; int low_watermark; int high_watermark; @@ -64,7 +63,7 @@ struct flow_cache { atomic_t flow_cache_genid = ATOMIC_INIT(0); EXPORT_SYMBOL(flow_cache_genid); static struct flow_cache flow_cache_global; -static struct kmem_cache *flow_cachep; +static struct kmem_cache *flow_cachep __read_mostly; static DEFINE_SPINLOCK(flow_cache_gc_lock); static LIST_HEAD(flow_cache_gc_list); @@ -181,11 +180,7 @@ static u32 flow_hash_code(struct flow_cache *fc, & (flow_cache_hash_size(fc) - 1)); } -#if (BITS_PER_LONG == 64) -typedef u64 flow_compare_t; -#else -typedef u32 flow_compare_t; -#endif +typedef unsigned long flow_compare_t; /* I hear what you're saying, use memcmp. But memcmp cannot make * important assumptions that we can here, such as alignment and @@ -357,62 +352,73 @@ void flow_cache_flush(void) put_online_cpus(); } -static void __init flow_cache_cpu_prepare(struct flow_cache *fc, - struct flow_cache_percpu *fcp) +static int __cpuinit flow_cache_cpu_prepare(struct flow_cache *fc, int cpu) { - fcp->hash_table = (struct hlist_head *) - __get_free_pages(GFP_KERNEL|__GFP_ZERO, fc->order); - if (!fcp->hash_table) - panic("NET: failed to allocate flow cache order %lu\n", fc->order); + struct flow_cache_percpu *fcp = per_cpu_ptr(fc->percpu, cpu); + size_t sz = sizeof(struct hlist_head) * flow_cache_hash_size(fc); - fcp->hash_rnd_recalc = 1; - fcp->hash_count = 0; - tasklet_init(&fcp->flush_tasklet, flow_cache_flush_tasklet, 0); + 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 %zu\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(struct notifier_block *nfb, +static int __cpuinit flow_cache_cpu(struct notifier_block *nfb, unsigned long action, void *hcpu) { struct flow_cache *fc = container_of(nfb, struct flow_cache, hotcpu_notifier); - int cpu = (unsigned long) hcpu; + int res, cpu = (unsigned long) hcpu; struct flow_cache_percpu *fcp = per_cpu_ptr(fc->percpu, cpu); - if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) + switch (action) { + case CPU_UP_PREPARE: + case CPU_UP_PREPARE_FROZEN: + res = flow_cache_cpu_prepare(fc, cpu); + if (res) + return notifier_from_errno(res); + break; + case CPU_DEAD: + case CPU_DEAD_FROZEN: __flow_cache_shrink(fc, fcp, 0); + break; + } return NOTIFY_OK; } -static int flow_cache_init(struct flow_cache *fc) +static int __init flow_cache_init(struct flow_cache *fc) { - unsigned long order; int i; fc->hash_shift = 10; fc->low_watermark = 2 * flow_cache_hash_size(fc); fc->high_watermark = 4 * flow_cache_hash_size(fc); - for (order = 0; - (PAGE_SIZE << order) < - (sizeof(struct hlist_head)*flow_cache_hash_size(fc)); - order++) - /* NOTHING */; - fc->order = order; fc->percpu = alloc_percpu(struct flow_cache_percpu); + if (!fc->percpu) + return -ENOMEM; - 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); - - for_each_possible_cpu(i) - flow_cache_cpu_prepare(fc, per_cpu_ptr(fc->percpu, i)); - + for_each_online_cpu(i) { + if (flow_cache_cpu_prepare(fc, i)) + return -ENOMEM; + } fc->hotcpu_notifier = (struct notifier_block){ .notifier_call = flow_cache_cpu, }; register_hotcpu_notifier(&fc->hotcpu_notifier); + 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; } -- 2.7.4