net: rds: fix per-cpu helper usage (c196403b) · Commits · 戴 / test

commit "net: rds: use this_cpu_* per-cpu helper" broke per-cpu handling for rds. chpfirst is the result of __this_cpu_read(), so it is an absolute pointer and not __percpu. Therefore, __this_cpu_write() should not operate on chpfirst, but rather on cache->percpu->first, just like __this_cpu_read() did before. Cc: <stable@vger.kernel.org> # 3.8+ Signed-off-byd Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by:

David S. Miller <davem@davemloft.net>

net/rds/ib_recv.c

+3 −4

Original line number	Diff line number	Diff line
		@@ -421,8 +421,7 @@ static void rds_ib_recv_cache_put(struct list_head *new_item,
		struct rds_ib_refill_cache *cache)
		{
		unsigned long flags;
		struct list_head *old;
		struct list_head __percpu *chpfirst;
		struct list_head old, chpfirst;

		local_irq_save(flags);

		@@ -432,7 +431,7 @@ static void rds_ib_recv_cache_put(struct list_head *new_item,
		else /* put on front */
		list_add_tail(new_item, chpfirst);

		__this_cpu_write(chpfirst, new_item);
		__this_cpu_write(cache->percpu->first, new_item);
		__this_cpu_inc(cache->percpu->count);

		if (__this_cpu_read(cache->percpu->count) < RDS_IB_RECYCLE_BATCH_COUNT)
		@@ -452,7 +451,7 @@ static void rds_ib_recv_cache_put(struct list_head *new_item,
		} while (old);


		__this_cpu_write(chpfirst, NULL);
		__this_cpu_write(cache->percpu->first, NULL);
		__this_cpu_write(cache->percpu->count, 0);
		end:
		local_irq_restore(flags);

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