@@ -26,7 +26,10 @@
#include <linux/security.h>
struct flow_cache_entry {
- struct flow_cache_entry *next;
+ union {
+ struct hlist_node hlist;
+ struct list_head gc_list;
+ } u;
u16 family;
u8 dir;
u32 genid;
@@ -36,7 +39,7 @@ struct flow_cache_entry {
};
struct flow_cache_percpu {
- struct flow_cache_entry ** hash_table;
+ struct hlist_head * hash_table;
int hash_count;
u32 hash_rnd;
int hash_rnd_recalc;
@@ -63,6 +66,9 @@ atomic_t flow_cache_genid = ATOMIC_INIT(0);
static struct flow_cache flow_cache_global;
static struct kmem_cache *flow_cachep;
+static DEFINE_SPINLOCK(flow_cache_gc_lock);
+static LIST_HEAD(flow_cache_gc_list);
+
#define flow_cache_hash_size(cache) (1 << (cache)->hash_shift)
#define FLOW_HASH_RND_PERIOD (10 * 60 * HZ)
@@ -78,36 +84,62 @@ static void flow_cache_new_hashrnd(unsigned long arg)
add_timer(&fc->rnd_timer);
}
-static void flow_entry_kill(struct flow_cache *fc,
- struct flow_cache_percpu *fcp,
- struct flow_cache_entry *fle)
+static void flow_entry_kill(struct flow_cache_entry *fle)
{
if (fle->object)
atomic_dec(fle->object_ref);
kmem_cache_free(flow_cachep, fle);
- fcp->hash_count--;
}
+static void flow_cache_gc_task(struct work_struct *work)
+{
+ struct list_head gc_list;
+ struct flow_cache_entry *fce, *n;
+
+ INIT_LIST_HEAD(&gc_list);
+ spin_lock_bh(&flow_cache_gc_lock);
+ list_splice_tail_init(&flow_cache_gc_list, &gc_list);
+ spin_unlock_bh(&flow_cache_gc_lock);
+
+ list_for_each_entry_safe(fce, n, &gc_list, u.gc_list)
+ flow_entry_kill(fce);
+}
+static DECLARE_WORK(flow_cache_gc_work, flow_cache_gc_task);
+
static void __flow_cache_shrink(struct flow_cache *fc,
struct flow_cache_percpu *fcp,
int shrink_to)
{
- struct flow_cache_entry *fle, **flp;
- int i;
+ struct flow_cache_entry *fce;
+ struct hlist_node *entry, *tmp;
+ struct list_head gc_list;
+ int i, deleted = 0;
+ INIT_LIST_HEAD(&gc_list);
for (i = 0; i < flow_cache_hash_size(fc); i++) {
- int k = 0;
-
- flp = &fcp->hash_table[i];
- while ((fle = *flp) != NULL && k < shrink_to) {
- k++;
- flp = &fle->next;
- }
- while ((fle = *flp) != NULL) {
- *flp = fle->next;
- flow_entry_kill(fc, fcp, fle);
+ int saved = 0;
+
+ hlist_for_each_entry_safe(fce, entry, tmp,
+ &fcp->hash_table[i], u.hlist) {
+ if (saved < shrink_to) {
+ saved++;
+ } else {
+ deleted++;
+ hlist_del(&fce->u.hlist);
+ list_add_tail(&fce->u.gc_list, &gc_list);
+ }
}
}
+
+ if (deleted) {
+ fcp->hash_count -= deleted;
+
+ spin_lock_bh(&flow_cache_gc_lock);
+ list_splice_tail(&gc_list, &flow_cache_gc_list);
+ spin_unlock_bh(&flow_cache_gc_lock);
+
+ schedule_work(&flow_cache_gc_work);
+ }
}
static void flow_cache_shrink(struct flow_cache *fc,
@@ -171,7 +203,8 @@ void *flow_cache_lookup(struct net *net, struct flowi *key, u16 family, u8 dir,
{
struct flow_cache *fc = &flow_cache_global;
struct flow_cache_percpu *fcp;
- struct flow_cache_entry *fle, **head;
+ struct flow_cache_entry *fle;
+ struct hlist_node *entry;
unsigned int hash;
local_bh_disable();
@@ -187,8 +220,7 @@ void *flow_cache_lookup(struct net *net, struct flowi *key, u16 family, u8 dir,
flow_new_hash_rnd(fc, fcp);
hash = flow_hash_code(fc, fcp, key);
- head = &fcp->hash_table[hash];
- for (fle = *head; fle; fle = fle->next) {
+ hlist_for_each_entry(fle, entry, &fcp->hash_table[hash], u.hlist) {
if (fle->family == family &&
fle->dir == dir &&
flow_key_compare(key, &fle->key) == 0) {
@@ -211,12 +243,12 @@ void *flow_cache_lookup(struct net *net, struct flowi *key, u16 family, u8 dir,
fle = kmem_cache_alloc(flow_cachep, GFP_ATOMIC);
if (fle) {
- fle->next = *head;
- *head = fle;
fle->family = family;
fle->dir = dir;
memcpy(&fle->key, key, sizeof(*key));
fle->object = NULL;
+
+ hlist_add_head(&fle->u.hlist, &fcp->hash_table[hash]);
fcp->hash_count++;
}
}
@@ -253,24 +285,38 @@ 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;
- int i;
+ struct flow_cache_entry *fle;
+ struct hlist_node *entry, *tmp;
+ struct list_head gc_list;
+ int i, deleted = 0;
+ unsigned genid;
+ INIT_LIST_HEAD(&gc_list);
fcp = per_cpu_ptr(fc->percpu, smp_processor_id());
for (i = 0; i < flow_cache_hash_size(fc); i++) {
- struct flow_cache_entry *fle;
-
- fle = fcp->hash_table[i];
- for (; fle; fle = fle->next) {
- unsigned genid = atomic_read(&flow_cache_genid);
+ hlist_for_each_entry_safe(fle, entry, tmp,
+ &fcp->hash_table[i], u.hlist) {
+ genid = atomic_read(&flow_cache_genid);
if (!fle->object || fle->genid == genid)
continue;
- fle->object = NULL;
- atomic_dec(fle->object_ref);
+ deleted++;
+ hlist_del(&fle->u.hlist);
+ list_add_tail(&fle->u.gc_list, &gc_list);
}
}
+ if (deleted) {
+ fcp->hash_count -= deleted;
+
+ spin_lock_bh(&flow_cache_gc_lock);
+ list_splice_tail(&gc_list, &flow_cache_gc_list);
+ spin_unlock_bh(&flow_cache_gc_lock);
+
+ schedule_work(&flow_cache_gc_work);
+ }
+
if (atomic_dec_and_test(&info->cpuleft))
complete(&info->completion);
}
@@ -312,7 +358,7 @@ void flow_cache_flush(void)
static void __cpuinit flow_cache_cpu_prepare(struct flow_cache *fc,
struct flow_cache_percpu *fcp)
{
- fcp->hash_table = (struct flow_cache_entry **)
+ fcp->hash_table = (struct hlist_head *)
__get_free_pages(GFP_KERNEL|__GFP_ZERO, fc->order);
fcp->hash_rnd_recalc = 1;
fcp->hash_count = 0;
@@ -359,7 +405,7 @@ static int flow_cache_init(struct flow_cache *fc)
for (order = 0;
(PAGE_SIZE << order) <
- (sizeof(struct flow_cache_entry *)*flow_cache_hash_size(fc));
+ (sizeof(struct hlist_head)*flow_cache_hash_size(fc));
order++)
/* NOTHING */;
fc->order = order;
Speed up lookups by freeing flow cache entries later. This is also in preparation to have virtual entry destructor that might do more work. As gc_list is more effective with double linked list, the flow cache is converted to use common hlist and list macroes where appropriate. Signed-off-by: Timo Teras <timo.teras@iki.fi> --- net/core/flow.c | 112 ++++++++++++++++++++++++++++++++++++++---------------- 1 files changed, 79 insertions(+), 33 deletions(-)