Commit 6af645a5 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

net: net_{enable|disable}_timestamp() optimizations 



Adopting atomic_try_cmpxchg() makes the code cleaner.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 30189806

net/core/dev.c

+6 −12
Original line number Diff line number Diff line
@@ -2073,13 +2073,10 @@ static DECLARE_WORK(netstamp_work, netstamp_clear); 
void net_enable_timestamp(void)

{

#ifdef CONFIG_JUMP_LABEL

	int wanted;

	int wanted = atomic_read(&netstamp_wanted);



	while (1) {

		wanted = atomic_read(&netstamp_wanted);

		if (wanted <= 0)

			break;

		if (atomic_cmpxchg(&netstamp_wanted, wanted, wanted + 1) == wanted)

	while (wanted > 0) {

		if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted + 1))

			return;

	}

	atomic_inc(&netstamp_needed_deferred);
@@ -2093,13 +2090,10 @@ EXPORT_SYMBOL(net_enable_timestamp); 
void net_disable_timestamp(void)

{

#ifdef CONFIG_JUMP_LABEL

	int wanted;

	int wanted = atomic_read(&netstamp_wanted);



	while (1) {

		wanted = atomic_read(&netstamp_wanted);

		if (wanted <= 1)

			break;

		if (atomic_cmpxchg(&netstamp_wanted, wanted, wanted - 1) == wanted)

	while (wanted > 1) {

		if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted - 1))

			return;

	}

	atomic_dec(&netstamp_needed_deferred);