[PATCH 5/7] resource: Handle simple alignment inside __find_empty_resource_slot()

Ilpo Järvinen
2023-12-22T12:30:15Z

allocate_resource() accepts alignf callback to perform custom alignment
beyond constraint->align. If alignf is NULL, simple_align_resource() is
used which only returns avail->start (no change).

Using avail->start directly is natural and can be done with a
conditional in __find_empty_resource_slot() instead which avoids
unnecessarily using callback. It makes the code inside
__find_empty_resource_slot() more obvious and removes the need for the
caller to provide constraint->alignf unnecessarily.

This is preparation for exporting find_empty_resource_slot().

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
---
kernel/resource.c | 21 ++++++++-------------
1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/kernel/resource.c b/kernel/resource.c
index 9d7920104120..80d64b6467b3 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -563,14 +563,6 @@ void __weak arch_remove_reservations(struct resource *avail)
{
}

-static resource_size_t simple_align_resource(void *data,
- const struct resource *avail,
- resource_size_t size,
- resource_size_t align)
-{
- return avail->start;
-}
-
static void resource_clip(struct resource *res, resource_size_t min,
resource_size_t max)
{
@@ -590,6 +582,7 @@ static int __find_empty_resource_slot(struct resource *root, struct resource *ol
{
struct resource *this = root->child;
struct resource tmp = *new, avail, alloc;
+ resource_alignf alignf = constraint->alignf;

tmp.start = root->start;
/*
@@ -618,8 +611,13 @@ static int __find_empty_resource_slot(struct resource *root, struct resource *ol
avail.flags = new->flags & ~IORESOURCE_UNSET;
if (avail.start >= tmp.start) {
alloc.flags = avail.flags;
- alloc.start = constraint->alignf(constraint->alignf_data, &avail,
- size, constraint->align);
+ if (alignf) {
+ alloc.start = alignf(constraint->alignf_data,
+ &avail, size,
+ constraint->align);
+ } else {
+ alloc.start = avail.start;
+ }
alloc.end = alloc.start + size - 1;
if (alloc.start <= alloc.end &&
resource_contains(&avail, &alloc)) {
@@ -730,9 +728,6 @@ int allocate_resource(struct resource *root, struct resource *new,
int err;
struct resource_constraint constraint;

- if (!alignf)
- alignf = simple_align_resource;
-
constraint.min = min;
constraint.max = max;
constraint.align = align;
--
2.30.2