net/flowcache: Convert to hotplug state machine

Install the callbacks via the state machine. Use multi state support to avoid
custom list handling for the multiple instances.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: netdev@vger.kernel.org
Cc: rt@linutronix.de
Cc: "David S. Miller" <davem@davemloft.net>
Link: http://lkml.kernel.org/r/20161103145021.28528-10-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 394eb7ed53be785106635d08ced6040aa135ef78..86b940f19df866316646b62a5359a493bd0c3967 100644 (file)
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -56,6 +56,7 @@ enum cpuhp_state {
        CPUHP_ARM_SHMOBILE_SCU_PREPARE,
        CPUHP_SH_SH3X_PREPARE,
        CPUHP_BLK_MQ_PREPARE,
+       CPUHP_NET_FLOW_PREPARE,
        CPUHP_TIMERS_DEAD,
        CPUHP_NOTF_ERR_INJ_PREPARE,
        CPUHP_MIPS_SOC_PREPARE,

diff --git a/include/net/flow.h b/include/net/flow.h
index 035aa7716967802340ae3bd4e915c45f33f1383e..2e386bd6ee634c379ac08e3a1a19e10f4b6a95d6 100644 (file)
--- a/include/net/flow.h
+++ b/include/net/flow.h
@@ -239,6 +239,7 @@ struct flow_cache_object *flow_cache_lookup(struct net *net,
                                            void *ctx);
 int flow_cache_init(struct net *net);
 void flow_cache_fini(struct net *net);
+void flow_cache_hp_init(void);
 
 void flow_cache_flush(struct net *net);
 void flow_cache_flush_deferred(struct net *net);

diff --git a/include/net/flowcache.h b/include/net/flowcache.h
index c8f665ec6e0d3d5249a7dd48dcaee41cb9b895dc..9caf3bfc8d2dafcc89064ec54e78682244d71fb7 100644 (file)
--- a/include/net/flowcache.h
+++ b/include/net/flowcache.h
@@ -17,7 +17,7 @@ struct flow_cache_percpu {
 struct flow_cache {
        u32                             hash_shift;
        struct flow_cache_percpu __percpu *percpu;
-       struct notifier_block           hotcpu_notifier;
+       struct hlist_node               node;
        int                             low_watermark;
        int                             high_watermark;
        struct timer_list               rnd_timer;

diff --git a/net/core/flow.c b/net/core/flow.c
index 3937b1b68d5bc7ad50691716ac1612332a5dc997..841fd7f87b304cafb95a151cb391d8efd30849bf 100644 (file)
--- a/net/core/flow.c
+++ b/net/core/flow.c
@@ -419,28 +419,20 @@ static int flow_cache_cpu_prepare(struct flow_cache *fc, int cpu)
        return 0;
 }
 
-static int flow_cache_cpu(struct notifier_block *nfb,
-                         unsigned long action,
-                         void *hcpu)
+static int flow_cache_cpu_up_prep(unsigned int cpu, struct hlist_node *node)
 {
-       struct flow_cache *fc = container_of(nfb, struct flow_cache,
-                                               hotcpu_notifier);
-       int res, cpu = (unsigned long) hcpu;
+       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);
 
-       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;
+       __flow_cache_shrink(fc, fcp, 0);
+       return 0;
 }
 
 int flow_cache_init(struct net *net)
@@ -467,18 +459,8 @@ int flow_cache_init(struct net *net)
        if (!fc->percpu)
                return -ENOMEM;
 
-       cpu_notifier_register_begin();
-
-       for_each_online_cpu(i) {
-               if (flow_cache_cpu_prepare(fc, i))
-                       goto err;
-       }
-       fc->hotcpu_notifier = (struct notifier_block){
-               .notifier_call = flow_cache_cpu,
-       };
-       __register_hotcpu_notifier(&fc->hotcpu_notifier);
-
-       cpu_notifier_register_done();
+       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);
@@ -494,8 +476,6 @@ err:
                fcp->hash_table = NULL;
        }
 
-       cpu_notifier_register_done();
-
        free_percpu(fc->percpu);
        fc->percpu = NULL;
 
@@ -509,7 +489,8 @@ void flow_cache_fini(struct net *net)
        struct flow_cache *fc = &net->xfrm.flow_cache_global;
 
        del_timer_sync(&fc->rnd_timer);
-       unregister_hotcpu_notifier(&fc->hotcpu_notifier);
+
+       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);
@@ -521,3 +502,14 @@ void flow_cache_fini(struct net *net)
        fc->percpu = NULL;
 }
 EXPORT_SYMBOL(flow_cache_fini);
+
+void __init flow_cache_hp_init(void)
+{
+       int ret;
+
+       ret = cpuhp_setup_state_multi(CPUHP_NET_FLOW_PREPARE,
+                                     "net/flow:prepare",
+                                     flow_cache_cpu_up_prep,
+                                     flow_cache_cpu_dead);
+       WARN_ON(ret < 0);
+}

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index fd6986634e6fe4dc77993854323d7558637b94bc..4a8eff11bdad56136d1d0bacd1dbdf4058a292c5 100644 (file)
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -3111,6 +3111,7 @@ static struct pernet_operations __net_initdata xfrm_net_ops = {
 
 void __init xfrm_init(void)
 {
+       flow_cache_hp_init();
        register_pernet_subsys(&xfrm_net_ops);
        seqcount_init(&xfrm_policy_hash_generation);
        xfrm_input_init();