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-rw-r--r--net/core/flow.c137
1 files changed, 100 insertions, 37 deletions
diff --git a/net/core/flow.c b/net/core/flow.c
index 127c8a7ffd61..dfa602ceb8cd 100644
--- a/net/core/flow.c
+++ b/net/core/flow.c
@@ -22,7 +22,7 @@
#include <linux/cpumask.h>
#include <linux/mutex.h>
#include <net/flow.h>
-#include <asm/atomic.h>
+#include <linux/atomic.h>
#include <linux/security.h>
struct flow_cache_entry {
@@ -30,6 +30,7 @@ struct flow_cache_entry {
struct hlist_node hlist;
struct list_head gc_list;
} u;
+ struct net *net;
u16 family;
u8 dir;
u32 genid;
@@ -131,14 +132,14 @@ static void __flow_cache_shrink(struct flow_cache *fc,
int shrink_to)
{
struct flow_cache_entry *fle;
- struct hlist_node *entry, *tmp;
+ struct hlist_node *tmp;
LIST_HEAD(gc_list);
int i, deleted = 0;
for (i = 0; i < flow_cache_hash_size(fc); i++) {
int saved = 0;
- hlist_for_each_entry_safe(fle, entry, tmp,
+ hlist_for_each_entry_safe(fle, tmp,
&fcp->hash_table[i], u.hlist) {
if (saved < shrink_to &&
flow_entry_valid(fle)) {
@@ -172,31 +173,28 @@ static void flow_new_hash_rnd(struct flow_cache *fc,
static u32 flow_hash_code(struct flow_cache *fc,
struct flow_cache_percpu *fcp,
- struct flowi *key)
+ const struct flowi *key,
+ size_t keysize)
{
- u32 *k = (u32 *) key;
+ const u32 *k = (const u32 *) key;
+ const u32 length = keysize * sizeof(flow_compare_t) / sizeof(u32);
- return jhash2(k, (sizeof(*key) / sizeof(u32)), fcp->hash_rnd)
+ return jhash2(k, length, fcp->hash_rnd)
& (flow_cache_hash_size(fc) - 1);
}
-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
- * constant size.
+ * important assumptions that we can here, such as alignment.
*/
-static int flow_key_compare(struct flowi *key1, struct flowi *key2)
+static int flow_key_compare(const struct flowi *key1, const struct flowi *key2,
+ size_t keysize)
{
- flow_compare_t *k1, *k1_lim, *k2;
- const int n_elem = sizeof(struct flowi) / sizeof(flow_compare_t);
-
- BUILD_BUG_ON(sizeof(struct flowi) % sizeof(flow_compare_t));
+ const flow_compare_t *k1, *k1_lim, *k2;
- k1 = (flow_compare_t *) key1;
- k1_lim = k1 + n_elem;
+ k1 = (const flow_compare_t *) key1;
+ k1_lim = k1 + keysize;
- k2 = (flow_compare_t *) key2;
+ k2 = (const flow_compare_t *) key2;
do {
if (*k1++ != *k2++)
@@ -207,14 +205,14 @@ static int flow_key_compare(struct flowi *key1, struct flowi *key2)
}
struct flow_cache_object *
-flow_cache_lookup(struct net *net, struct flowi *key, u16 family, u8 dir,
+flow_cache_lookup(struct net *net, const struct flowi *key, u16 family, u8 dir,
flow_resolve_t resolver, void *ctx)
{
struct flow_cache *fc = &flow_cache_global;
struct flow_cache_percpu *fcp;
struct flow_cache_entry *fle, *tfle;
- struct hlist_node *entry;
struct flow_cache_object *flo;
+ size_t keysize;
unsigned int hash;
local_bh_disable();
@@ -222,6 +220,11 @@ flow_cache_lookup(struct net *net, struct flowi *key, u16 family, u8 dir,
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)
@@ -230,11 +233,12 @@ flow_cache_lookup(struct net *net, struct flowi *key, u16 family, u8 dir,
if (fcp->hash_rnd_recalc)
flow_new_hash_rnd(fc, fcp);
- hash = flow_hash_code(fc, fcp, key);
- hlist_for_each_entry(tfle, entry, &fcp->hash_table[hash], u.hlist) {
- if (tfle->family == family &&
+ 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) == 0) {
+ flow_key_compare(key, &tfle->key, keysize) == 0) {
fle = tfle;
break;
}
@@ -246,9 +250,10 @@ flow_cache_lookup(struct net *net, struct flowi *key, u16 family, u8 dir,
fle = kmem_cache_alloc(flow_cachep, GFP_ATOMIC);
if (fle) {
+ fle->net = net;
fle->family = family;
fle->dir = dir;
- memcpy(&fle->key, key, sizeof(*key));
+ 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++;
@@ -280,7 +285,7 @@ nocache:
else
fle->genid--;
} else {
- if (flo && !IS_ERR(flo))
+ if (!IS_ERR_OR_NULL(flo))
flo->ops->delete(flo);
}
ret_object:
@@ -295,13 +300,13 @@ static void flow_cache_flush_tasklet(unsigned long data)
struct flow_cache *fc = info->cache;
struct flow_cache_percpu *fcp;
struct flow_cache_entry *fle;
- struct hlist_node *entry, *tmp;
+ struct hlist_node *tmp;
LIST_HEAD(gc_list);
int i, deleted = 0;
fcp = this_cpu_ptr(fc->percpu);
for (i = 0; i < flow_cache_hash_size(fc); i++) {
- hlist_for_each_entry_safe(fle, entry, tmp,
+ hlist_for_each_entry_safe(fle, tmp,
&fcp->hash_table[i], u.hlist) {
if (flow_entry_valid(fle))
continue;
@@ -318,14 +323,30 @@ static void flow_cache_flush_tasklet(unsigned long data)
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;
+ 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;
- int cpu;
struct tasklet_struct *tasklet;
- cpu = smp_processor_id();
- tasklet = &per_cpu_ptr(info->cache->percpu, cpu)->flush_tasklet;
+ tasklet = &this_cpu_ptr(info->cache->percpu)->flush_tasklet;
tasklet->data = (unsigned long)info;
tasklet_schedule(tasklet);
}
@@ -334,25 +355,55 @@ void flow_cache_flush(void)
{
struct flow_flush_info info;
static DEFINE_MUTEX(flow_flush_sem);
+ 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(&flow_flush_sem);
info.cache = &flow_cache_global;
- atomic_set(&info.cpuleft, num_online_cpus());
+ 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();
- smp_call_function(flow_cache_flush_per_cpu, &info, 0);
- flow_cache_flush_tasklet((unsigned long)&info);
+ 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(&flow_flush_sem);
put_online_cpus();
+ free_cpumask_var(mask);
+}
+
+static void flow_cache_flush_task(struct work_struct *work)
+{
+ flow_cache_flush();
+}
+
+static DECLARE_WORK(flow_cache_flush_work, flow_cache_flush_task);
+
+void flow_cache_flush_deferred(void)
+{
+ schedule_work(&flow_cache_flush_work);
}
-static int __cpuinit flow_cache_cpu_prepare(struct flow_cache *fc, int cpu)
+static int flow_cache_cpu_prepare(struct flow_cache *fc, int cpu)
{
struct flow_cache_percpu *fcp = per_cpu_ptr(fc->percpu, cpu);
size_t sz = sizeof(struct hlist_head) * flow_cache_hash_size(fc);
@@ -370,7 +421,7 @@ static int __cpuinit flow_cache_cpu_prepare(struct flow_cache *fc, int cpu)
return 0;
}
-static int __cpuinit flow_cache_cpu(struct notifier_block *nfb,
+static int flow_cache_cpu(struct notifier_block *nfb,
unsigned long action,
void *hcpu)
{
@@ -407,7 +458,7 @@ static int __init flow_cache_init(struct flow_cache *fc)
for_each_online_cpu(i) {
if (flow_cache_cpu_prepare(fc, i))
- return -ENOMEM;
+ goto err;
}
fc->hotcpu_notifier = (struct notifier_block){
.notifier_call = flow_cache_cpu,
@@ -420,6 +471,18 @@ static int __init flow_cache_init(struct flow_cache *fc)
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;
}
static int __init flow_cache_init_global(void)
generated by cgit (git 2.34.1) at 2025-08-11 03:43:15 +0000