Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 2224b671 authored by Ian Munsie's avatar Ian Munsie Committed by Michael Ellerman
Browse files

cxl: Fix allocating a minimum of 2 pages for the SPA 



The Scheduled Process Area is allocated dynamically with enough pages to
fit at least as many processes as the AFU descriptor indicated. Since
the calculation is non-trivial, it does this by calculating how many
processes could fit in an allocation of a given order, and increasing
that order until it can fit enough processes or hits the maximum
supported size.

Currently, it will start this search using a SPA of 2 pages instead of
1. This can waste a page of memory if the AFU's maximum number of
supported processes was small enough to fit in one page.

Fix the algorithm to start the search at 1 page.

Signed-off-by: default avatarIan Munsie <imunsie@au1.ibm.com>
Reviewed-by: default avatarFrederic Barrat <fbarrat@linux.vnet.ibm.com>
Reviewed-by: default avatarAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent 49e9c99f

drivers/misc/cxl/native.c

+1 −1
Original line number Diff line number Diff line
@@ -189,7 +189,7 @@ int cxl_alloc_spa(struct cxl_afu *afu) 
	unsigned spa_size;



	/* Work out how many pages to allocate */

	afu->native->spa_order = 0;

	afu->native->spa_order = -1;

	do {

		afu->native->spa_order++;

		spa_size = (1 << afu->native->spa_order) * PAGE_SIZE;