net-gro: use ffs() to speedup napi_gro_flush()

We very often have few flows/chains to look at, and we
might increase GRO_HASH_BUCKETS to 32 or 64 in the future.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2018-11-21 11:39:28 -08:00 committed by David S. Miller
parent d72ff4b4ea
commit 42519ede4f
1 changed files with 6 additions and 4 deletions

View File

@ -5364,11 +5364,13 @@ static void __napi_gro_flush_chain(struct napi_struct *napi, u32 index,
*/
void napi_gro_flush(struct napi_struct *napi, bool flush_old)
{
u32 i;
unsigned long bitmask = napi->gro_bitmask;
unsigned int i, base = ~0U;
for (i = 0; i < GRO_HASH_BUCKETS; i++) {
if (test_bit(i, &napi->gro_bitmask))
__napi_gro_flush_chain(napi, i, flush_old);
while ((i = ffs(bitmask)) != 0) {
bitmask >>= i;
base += i;
__napi_gro_flush_chain(napi, base, flush_old);
}
}
EXPORT_SYMBOL(napi_gro_flush);