tree 9342e9b242f6feef581c57d1e931d65ad5abbc5a
parent 89e960b5a99511f21d07da50eb34aeeb46cfba0f
author Li RongQing <lirongqing@baidu.com> 1581387224 +0800
committer David S. Miller <davem@davemloft.net> 1581631911 -0800

page_pool: refill page when alloc.count of pool is zero

"do {} while" in page_pool_refill_alloc_cache will always
refill page once whether refill is true or false, and whether
alloc.count of pool is less than PP_ALLOC_CACHE_REFILL or not
this is wrong, and will cause overflow of pool->alloc.cache

the caller of __page_pool_get_cached should provide guarantee
that pool->alloc.cache is safe to access, so in_serving_softirq
should be removed as suggested by Jesper Dangaard Brouer in
https://patchwork.ozlabs.org/patch/1233713/

so fix this issue by calling page_pool_refill_alloc_cache()
only when pool->alloc.count is zero

Fixes: 44768decb7c0 ("page_pool: handle page recycle for NUMA_NO_NODE condition")
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Suggested-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>