diff options
| -rw-r--r-- | net/ipv4/route.c | 83 |
1 files changed, 59 insertions, 24 deletions
diff --git a/net/ipv4/route.c b/net/ipv4/route.c index e4b6fb4b1f4..fcae074b7ae 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -133,13 +133,14 @@ static int ip_rt_mtu_expires = 10 * 60 * HZ; static int ip_rt_min_pmtu = 512 + 20 + 20; static int ip_rt_min_advmss = 256; static int ip_rt_secret_interval = 10 * 60 * HZ; +static int ip_rt_flush_expected; static unsigned long rt_deadline; #define RTprint(a...) printk(KERN_DEBUG a) static struct timer_list rt_flush_timer; -static void rt_check_expire(struct work_struct *work); -static DECLARE_DELAYED_WORK(expires_work, rt_check_expire); +static void rt_worker_func(struct work_struct *work); +static DECLARE_DELAYED_WORK(expires_work, rt_worker_func); static struct timer_list rt_secret_timer; /* @@ -561,7 +562,36 @@ static inline int compare_keys(struct flowi *fl1, struct flowi *fl2) (fl1->iif ^ fl2->iif)) == 0; } -static void rt_check_expire(struct work_struct *work) +/* + * Perform a full scan of hash table and free all entries. + * Can be called by a softirq or a process. + * In the later case, we want to be reschedule if necessary + */ +static void rt_do_flush(int process_context) +{ + unsigned int i; + struct rtable *rth, *next; + + for (i = 0; i <= rt_hash_mask; i++) { + if (process_context && need_resched()) + cond_resched(); + rth = rt_hash_table[i].chain; + if (!rth) + continue; + + spin_lock_bh(rt_hash_lock_addr(i)); + rth = rt_hash_table[i].chain; + rt_hash_table[i].chain = NULL; + spin_unlock_bh(rt_hash_lock_addr(i)); + + for (; rth; rth = next) { + next = rth->u.dst.rt_next; + rt_free(rth); + } + } +} + +static void rt_check_expire(void) { static unsigned int rover; unsigned int i = rover, goal; @@ -607,33 +637,33 @@ static void rt_check_expire(struct work_struct *work) spin_unlock_bh(rt_hash_lock_addr(i)); } rover = i; +} + +/* + * rt_worker_func() is run in process context. + * If a whole flush was scheduled, it is done. + * Else, we call rt_check_expire() to scan part of the hash table + */ +static void rt_worker_func(struct work_struct *work) +{ + if (ip_rt_flush_expected) { + ip_rt_flush_expected = 0; + rt_do_flush(1); + } else + rt_check_expire(); schedule_delayed_work(&expires_work, ip_rt_gc_interval); } /* This can run from both BH and non-BH contexts, the latter * in the case of a forced flush event. */ -static void rt_run_flush(unsigned long dummy) +static void rt_run_flush(unsigned long process_context) { - int i; - struct rtable *rth, *next; - rt_deadline = 0; get_random_bytes(&rt_hash_rnd, 4); - for (i = rt_hash_mask; i >= 0; i--) { - spin_lock_bh(rt_hash_lock_addr(i)); - rth = rt_hash_table[i].chain; - if (rth) - rt_hash_table[i].chain = NULL; - spin_unlock_bh(rt_hash_lock_addr(i)); - - for (; rth; rth = next) { - next = rth->u.dst.rt_next; - rt_free(rth); - } - } + rt_do_flush(process_context); } static DEFINE_SPINLOCK(rt_flush_lock); @@ -667,7 +697,7 @@ void rt_cache_flush(int delay) if (delay <= 0) { spin_unlock_bh(&rt_flush_lock); - rt_run_flush(0); + rt_run_flush(user_mode); return; } @@ -678,12 +708,17 @@ void rt_cache_flush(int delay) spin_unlock_bh(&rt_flush_lock); } +/* + * We change rt_hash_rnd and ask next rt_worker_func() invocation + * to perform a flush in process context + */ static void rt_secret_rebuild(unsigned long dummy) { - unsigned long now = jiffies; - - rt_cache_flush(0); - mod_timer(&rt_secret_timer, now + ip_rt_secret_interval); + get_random_bytes(&rt_hash_rnd, 4); + ip_rt_flush_expected = 1; + cancel_delayed_work(&expires_work); + schedule_delayed_work(&expires_work, HZ/10); + mod_timer(&rt_secret_timer, jiffies + ip_rt_secret_interval); } /* |