Faster shutdown and cleanups by freeing route attributes strictly from main loop (b2bac7ae) · Commits · 戴 / Bird

nest/route.h

+11 −3

Original line number	Diff line number	Diff line
		@@ -883,14 +883,22 @@ static inline rta rta_clone(rta r) {
		return r;
		}

		void rta__free(rta *r);
		#define RTA_OBSOLETE_LIMIT 512

		extern _Atomic u32 rta_obsolete_count;
		extern event rta_cleanup_event;

		static inline void rta_free(rta *r) {
		if (!r)
		return;

		u32 uc = atomic_fetch_sub_explicit(&r->uc, 1, memory_order_acq_rel);
		if (uc == 1)
		rta__free(r);
		if (uc > 1)
		return;

		u32 obs = atomic_fetch_add_explicit(&rta_obsolete_count, 1, memory_order_acq_rel);
		if (obs == RTA_OBSOLETE_LIMIT)
		ev_send(&global_work_list, &rta_cleanup_event);
		}

		rta rta_do_cow(rta o, linpool *lp);

nest/rt-attr.c

+53 −27

Original line number	Diff line number	Diff line
		@@ -1384,38 +1384,57 @@ rta_lookup(rta *o)
		return r;
		}

		void
		rta__free(rta *a)
		static void
		rta_cleanup(void *data UNUSED)
		{
		ASSERT(a->cached);
		u32 count = 0;
		rta *ax[RTA_OBSOLETE_LIMIT];

		RTA_LOCK;
		struct rta_cache *c = atomic_load_explicit(&rta_cache, memory_order_acquire);

		if (atomic_load_explicit(&a->uc, memory_order_acquire))
		for(u32 h=0; h<c->size; h++)
		for(rta a = atomic_load_explicit(&c->table[h], memory_order_acquire), next;
		a;
		a = next)
		{
		/* Acquired inbetween */
		RTA_UNLOCK;
		return;
		next = atomic_load_explicit(&a->next, memory_order_acquire);
		if (atomic_load_explicit(&a->uc, memory_order_acquire) > 0)
		continue;

		/* Check if the cleanup fits in the buffer */
		if (count == RTA_OBSOLETE_LIMIT)
		{
		ev_send(&global_work_list, &rta_cleanup_event);
		goto wait;
		}

		/* Relink the forward pointer */
		rta *next = atomic_load_explicit(&a->next, memory_order_acquire);
		atomic_store_explicit(a->pprev, next, memory_order_release);

		/* Relink the backwards pointer */
		if (next)
		next->pprev = a->pprev;

		/* Store for freeing and go to the next */
		ax[count++] = a;
		a = next;
		}

		wait:
		/* Wait until nobody knows about us */
		synchronize_rcu();

		if (atomic_load_explicit(&a->uc, memory_order_acquire))
		u32 freed = 0;

		for (u32 i=0; i<count; i++)
		{
		rta *a = ax[i];
		/* Acquired inbetween, relink back */
		if (atomic_load_explicit(&a->uc, memory_order_acquire))
		{
		rta_insert(a, c);
		RTA_UNLOCK;
		return;
		continue;
		}

		/* Cleared to free the memory */
		@@ -1426,10 +1445,17 @@ rta__free(rta *a)
		a->cached = 0;
		c->count--;
		sl_free(rta_slab(a), a);
		freed++;
		}

		atomic_fetch_sub_explicit(&rta_obsolete_count, freed, memory_order_release);

		RTA_UNLOCK;
		}

		_Atomic u32 rta_obsolete_count;
		event rta_cleanup_event = { .hook = rta_cleanup, .list = &global_work_list };

		rta *
		rta_do_cow(rta o, linpool lp)
		{

sysdep/unix/coroutine.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -201,5 +201,6 @@ struct coroutine coro_run(pool p, void (entry)(void ), void *data)
		void
		coro_yield(void)
		{
		usleep(100);
		const struct timespec req = { .tv_nsec = 100 };
		nanosleep(&req, NULL);
		}

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