From 51a9f5ae653979ac4bdbd81778a10431f0177e3c Mon Sep 17 00:00:00 2001 From: Vlad Buslov Date: Fri, 10 Aug 2018 20:51:54 +0300 Subject: [PATCH] net: core: protect rate estimator statistics pointer with lock Extend gen_new_estimator() to also take stats_lock when re-assigning rate estimator statistics pointer. (to be used by unlocked actions) Rename 'stats_lock' to 'lock' and change argument description to explain that it is now also used for control path. Signed-off-by: Vlad Buslov Signed-off-by: David S. Miller --- include/net/gen_stats.h | 4 ++-- net/core/gen_estimator.c | 21 +++++++++++++-------- 2 files changed, 15 insertions(+), 10 deletions(-) diff --git a/include/net/gen_stats.h b/include/net/gen_stats.h index 0304ba2ae353..883bb9085f15 100644 --- a/include/net/gen_stats.h +++ b/include/net/gen_stats.h @@ -59,13 +59,13 @@ int gnet_stats_finish_copy(struct gnet_dump *d); int gen_new_estimator(struct gnet_stats_basic_packed *bstats, struct gnet_stats_basic_cpu __percpu *cpu_bstats, struct net_rate_estimator __rcu **rate_est, - spinlock_t *stats_lock, + spinlock_t *lock, seqcount_t *running, struct nlattr *opt); void gen_kill_estimator(struct net_rate_estimator __rcu **ptr); int gen_replace_estimator(struct gnet_stats_basic_packed *bstats, struct gnet_stats_basic_cpu __percpu *cpu_bstats, struct net_rate_estimator __rcu **ptr, - spinlock_t *stats_lock, + spinlock_t *lock, seqcount_t *running, struct nlattr *opt); bool gen_estimator_active(struct net_rate_estimator __rcu **ptr); bool gen_estimator_read(struct net_rate_estimator __rcu **ptr, diff --git a/net/core/gen_estimator.c b/net/core/gen_estimator.c index 98fd12721221..e4e442d70c2d 100644 --- a/net/core/gen_estimator.c +++ b/net/core/gen_estimator.c @@ -112,7 +112,7 @@ static void est_timer(struct timer_list *t) * @bstats: basic statistics * @cpu_bstats: bstats per cpu * @rate_est: rate estimator statistics - * @stats_lock: statistics lock + * @lock: lock for statistics and control path * @running: qdisc running seqcount * @opt: rate estimator configuration TLV * @@ -128,7 +128,7 @@ static void est_timer(struct timer_list *t) int gen_new_estimator(struct gnet_stats_basic_packed *bstats, struct gnet_stats_basic_cpu __percpu *cpu_bstats, struct net_rate_estimator __rcu **rate_est, - spinlock_t *stats_lock, + spinlock_t *lock, seqcount_t *running, struct nlattr *opt) { @@ -154,19 +154,22 @@ int gen_new_estimator(struct gnet_stats_basic_packed *bstats, seqcount_init(&est->seq); intvl_log = parm->interval + 2; est->bstats = bstats; - est->stats_lock = stats_lock; + est->stats_lock = lock; est->running = running; est->ewma_log = parm->ewma_log; est->intvl_log = intvl_log; est->cpu_bstats = cpu_bstats; - if (stats_lock) + if (lock) local_bh_disable(); est_fetch_counters(est, &b); - if (stats_lock) + if (lock) local_bh_enable(); est->last_bytes = b.bytes; est->last_packets = b.packets; + + if (lock) + spin_lock_bh(lock); old = rcu_dereference_protected(*rate_est, 1); if (old) { del_timer_sync(&old->timer); @@ -179,6 +182,8 @@ int gen_new_estimator(struct gnet_stats_basic_packed *bstats, mod_timer(&est->timer, est->next_jiffies); rcu_assign_pointer(*rate_est, est); + if (lock) + spin_unlock_bh(lock); if (old) kfree_rcu(old, rcu); return 0; @@ -209,7 +214,7 @@ EXPORT_SYMBOL(gen_kill_estimator); * @bstats: basic statistics * @cpu_bstats: bstats per cpu * @rate_est: rate estimator statistics - * @stats_lock: statistics lock + * @lock: lock for statistics and control path * @running: qdisc running seqcount (might be NULL) * @opt: rate estimator configuration TLV * @@ -221,11 +226,11 @@ EXPORT_SYMBOL(gen_kill_estimator); int gen_replace_estimator(struct gnet_stats_basic_packed *bstats, struct gnet_stats_basic_cpu __percpu *cpu_bstats, struct net_rate_estimator __rcu **rate_est, - spinlock_t *stats_lock, + spinlock_t *lock, seqcount_t *running, struct nlattr *opt) { return gen_new_estimator(bstats, cpu_bstats, rate_est, - stats_lock, running, opt); + lock, running, opt); } EXPORT_SYMBOL(gen_replace_estimator); -- 2.11.0