Commit 8b0b1461 authored by Hannes Reinecke's avatar Hannes Reinecke Committed by Martin K. Petersen
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scsi: fcoe: Remove fcoe_select_cpu() 



The function fcoe_select_cpu() is just used to distribute incoming skbs
which start a new FC command sequence. But the network stack already
received (and processed) that skb, and there is a _really_ good chance
that all subsequent skbs for this sequence will be handled with the same
CPU. So we should just use the CPU on which this skb was allocated on and
save ourselves some overhead due to pointless scheduling.

Signed-off-by: default avatarHannes Reinecke <hare@kernel.org>
Link: https://lore.kernel.org/r/20250605062014.105302-1-hare@kernel.org


Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 19272b37

drivers/scsi/fcoe/fcoe.c

+1 −21
Original line number Diff line number Diff line
@@ -1299,26 +1299,6 @@ static void fcoe_thread_cleanup_local(unsigned int cpu) 
	flush_work(&p->work);

}



/**

 * fcoe_select_cpu() - Selects CPU to handle post-processing of incoming

 *			command.

 *

 * This routine selects next CPU based on cpumask to distribute

 * incoming requests in round robin.

 *

 * Returns: int CPU number

 */

static inline unsigned int fcoe_select_cpu(void)

{

	static unsigned int selected_cpu;



	selected_cpu = cpumask_next(selected_cpu, cpu_online_mask);

	if (selected_cpu >= nr_cpu_ids)

		selected_cpu = cpumask_first(cpu_online_mask);



	return selected_cpu;

}



/**

 * fcoe_rcv() - Receive packets from a net device

 * @skb:    The received packet
@@ -1405,7 +1385,7 @@ static int fcoe_rcv(struct sk_buff *skb, struct net_device *netdev, 
		cpu = ntohs(fh->fh_ox_id) & fc_cpu_mask;

	else {

		if (ntohs(fh->fh_rx_id) == FC_XID_UNKNOWN)

			cpu = fcoe_select_cpu();

			cpu = skb->alloc_cpu;

		else

			cpu = ntohs(fh->fh_rx_id) & fc_cpu_mask;

	}