Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-27 06:31:52 +00:00
Code Issues Packages Projects Releases Wiki Activity

vduse: Remove unnecessary spin lock protection

Browse Source 
Now we use domain->iotlb_lock to protect two different
variables: domain->bounce_maps->bounce_page and
domain->iotlb. But for domain->bounce_maps->bounce_page,
we actually don't need any synchronization between
vduse_domain_get_bounce_page() and vduse_domain_free_bounce_pages()
since vduse_domain_get_bounce_page() will only be called in
page fault handler and vduse_domain_free_bounce_pages() will
be called during file release.

So let's remove the unnecessary spin lock protection in
vduse_domain_get_bounce_page(). Then the usage of
domain->iotlb_lock could be more clear: the lock will be
only used to protect the domain->iotlb.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220803045523.23851-2-xieyongji@bytedance.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Xie Yongji 2022-08-03 12:55:19 +08:00 committed by Michael S. Tsirkin
parent 699b045a8e
commit c32ee69312
1 changed files with 2 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
drivers/vdpa/vdpa_user/iova_domain.c
View File

@ -211,17 +211,14 @@ static struct page *
vduse_domain_get_bounce_page(struct vduse_iova_domain *domain, u64 iova)
{
struct vduse_bounce_map *map;
struct page *page = NULL;
struct page *page;
spin_lock(&domain->iotlb_lock);
map = &domain->bounce_maps[iova >> PAGE_SHIFT];
if (!map->bounce_page)
goto out;
return NULL;
page = map->bounce_page;
get_page(page);
out:
spin_unlock(&domain->iotlb_lock);
return page;
}