Commit 494bc1d2 authored by Jakub Kicinski's avatar Jakub Kicinski Committed by David S. Miller
Browse files

net/tcp: use deferred jump label for TCP acked data hook 



User space can flip the clean_acked_data_enabled static branch
on and off with TLS offload when CONFIG_TLS_DEVICE is enabled.
jump_label.h suggests we use the delayed version in this case.

Deferred branches now also don't take the branch mutex on
decrement, so we avoid potential locking issues.

Signed-off-by: default avatarJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: default avatarSimon Horman <simon.horman@netronome.com>
Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 70610c92

include/net/tcp.h

+1 −1
Original line number Diff line number Diff line
@@ -2198,7 +2198,7 @@ extern struct static_key_false tcp_have_smc; 
void clean_acked_data_enable(struct inet_connection_sock *icsk,

			     void (*cad)(struct sock *sk, u32 ack_seq));

void clean_acked_data_disable(struct inet_connection_sock *icsk);



void clean_acked_data_flush(void);

#endif



#endif	/* _TCP_H */

net/ipv4/tcp_input.c

+11 −5
Original line number Diff line number Diff line
@@ -77,7 +77,7 @@ 
#include <asm/unaligned.h>

#include <linux/errqueue.h>

#include <trace/events/tcp.h>

#include <linux/static_key.h>

#include <linux/jump_label_ratelimit.h>

#include <net/busy_poll.h>



int sysctl_tcp_max_orphans __read_mostly = NR_FILE;
@@ -113,22 +113,28 @@ int sysctl_tcp_max_orphans __read_mostly = NR_FILE; 
#define REXMIT_NEW	2 /* FRTO-style transmit of unsent/new packets */



#if IS_ENABLED(CONFIG_TLS_DEVICE)

static DEFINE_STATIC_KEY_FALSE(clean_acked_data_enabled);

static DEFINE_STATIC_KEY_DEFERRED_FALSE(clean_acked_data_enabled, HZ);



void clean_acked_data_enable(struct inet_connection_sock *icsk,

			     void (*cad)(struct sock *sk, u32 ack_seq))

{

	icsk->icsk_clean_acked = cad;

	static_branch_inc(&clean_acked_data_enabled);

	static_branch_inc(&clean_acked_data_enabled.key);

}

EXPORT_SYMBOL_GPL(clean_acked_data_enable);



void clean_acked_data_disable(struct inet_connection_sock *icsk)

{

	static_branch_dec(&clean_acked_data_enabled);

	static_branch_slow_dec_deferred(&clean_acked_data_enabled);

	icsk->icsk_clean_acked = NULL;

}

EXPORT_SYMBOL_GPL(clean_acked_data_disable);



void clean_acked_data_flush(void)

{

	static_key_deferred_flush(&clean_acked_data_enabled);

}

EXPORT_SYMBOL_GPL(clean_acked_data_flush);

#endif



static void tcp_gro_dev_warn(struct sock *sk, const struct sk_buff *skb,
@@ -3598,7 +3604,7 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag) 
		icsk->icsk_retransmits = 0;



#if IS_ENABLED(CONFIG_TLS_DEVICE)

		if (static_branch_unlikely(&clean_acked_data_enabled))

		if (static_branch_unlikely(&clean_acked_data_enabled.key))

			if (icsk->icsk_clean_acked)

				icsk->icsk_clean_acked(sk, ack);

#endif

net/tls/tls_device.c

+1 −0
Original line number Diff line number Diff line
@@ -1036,4 +1036,5 @@ void __exit tls_device_cleanup(void) 
{

	unregister_netdevice_notifier(&tls_dev_notifier);

	flush_work(&tls_device_gc_work);

	clean_acked_data_flush();

}