Commit aaaaa663 authored by Sebastian Andrzej Siewior's avatar Sebastian Andrzej Siewior Committed by Paolo Abeni
Browse files

rds: Disable only bottom halves in rds_page_remainder_alloc() 



rds_page_remainder_alloc() is invoked from a preemptible context or a
tasklet. There is no need to disable interrupts for locking.

Use local_bh_disable() instead of local_irq_save() for locking.

Cc: Allison Henderson <allison.henderson@oracle.com>
Cc: linux-rdma@vger.kernel.org
Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://patch.msgid.link/20250512092736.229935-14-bigeasy@linutronix.de


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent 82d9e6b9

net/rds/page.c

+4 −5
Original line number Diff line number Diff line
@@ -69,7 +69,6 @@ int rds_page_remainder_alloc(struct scatterlist *scat, unsigned long bytes, 
			     gfp_t gfp)

{

	struct rds_page_remainder *rem;

	unsigned long flags;

	struct page *page;

	int ret;
@@ -88,7 +87,7 @@ int rds_page_remainder_alloc(struct scatterlist *scat, unsigned long bytes, 
	}



	rem = &per_cpu(rds_page_remainders, get_cpu());

	local_irq_save(flags);

	local_bh_disable();



	while (1) {

		/* avoid a tiny region getting stuck by tossing it */
@@ -116,13 +115,13 @@ int rds_page_remainder_alloc(struct scatterlist *scat, unsigned long bytes, 
		}



		/* alloc if there is nothing for us to use */

		local_irq_restore(flags);

		local_bh_enable();

		put_cpu();



		page = alloc_page(gfp);



		rem = &per_cpu(rds_page_remainders, get_cpu());

		local_irq_save(flags);

		local_bh_disable();



		if (!page) {

			ret = -ENOMEM;
@@ -140,7 +139,7 @@ int rds_page_remainder_alloc(struct scatterlist *scat, unsigned long bytes, 
		rem->r_offset = 0;

	}



	local_irq_restore(flags);

	local_bh_enable();

	put_cpu();

out:

	rdsdebug("bytes %lu ret %d %p %u %u\n", bytes, ret,