[PATCH v2] xen/grant-table: remove multiple BUG_ON on gnttab_interface

[PATCH v2] xen/grant-table: remove multiple BUG_ON on gnttab_interface

[Aditya Pakki]

gnttab_request_version() always sets the gnttab_interface variable
and the assertions to check for empty gnttab_interface is unnecessary.
The patch eliminates multiple such assertions.

Signed-off-by: Aditya Pakki <pakki001@umn.edu>
---
v1: Eliminate more BUG_ON calls, as suggested by Juergen Gross.
---
 drivers/xen/grant-table.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
index 49b381e104ef..7b36b51cdb9f 100644
--- a/drivers/xen/grant-table.c
+++ b/drivers/xen/grant-table.c
@@ -664,7 +664,6 @@ static int grow_gnttab_list(unsigned int more_frames)
 	unsigned int nr_glist_frames, new_nr_glist_frames;
 	unsigned int grefs_per_frame;
 
-	BUG_ON(gnttab_interface == NULL);
 	grefs_per_frame = gnttab_interface->grefs_per_grant_frame;
 
 	new_nr_grant_frames = nr_grant_frames + more_frames;
@@ -1160,7 +1159,6 @@ EXPORT_SYMBOL_GPL(gnttab_unmap_refs_sync);
 
 static unsigned int nr_status_frames(unsigned int nr_grant_frames)
 {
-	BUG_ON(gnttab_interface == NULL);
 	return gnttab_frames(nr_grant_frames, SPP);
 }
 
@@ -1388,7 +1386,6 @@ static int gnttab_expand(unsigned int req_entries)
 	int rc;
 	unsigned int cur, extra;
 
-	BUG_ON(gnttab_interface == NULL);
 	cur = nr_grant_frames;
 	extra = ((req_entries + gnttab_interface->grefs_per_grant_frame - 1) /
 		 gnttab_interface->grefs_per_grant_frame);
@@ -1423,7 +1420,6 @@ int gnttab_init(void)
 	/* Determine the maximum number of frames required for the
 	 * grant reference free list on the current hypervisor.
 	 */
-	BUG_ON(gnttab_interface == NULL);
 	max_nr_glist_frames = (max_nr_grant_frames *
 			       gnttab_interface->grefs_per_grant_frame / RPP);
 
-- 
2.20.1

Re: [PATCH v2] xen/grant-table: remove multiple BUG_ON on gnttab_interface

[Jürgen Groß]

On 17.12.19 21:53, Aditya Pakki wrote:
> gnttab_request_version() always sets the gnttab_interface variable
> and the assertions to check for empty gnttab_interface is unnecessary.
> The patch eliminates multiple such assertions.
> 
> Signed-off-by: Aditya Pakki <pakki001@umn.edu>

Reviewed-by: Juergen Gross <jgross@suse.com>


Juergen

Re: [PATCH v2] xen/grant-table: remove multiple BUG_ON on gnttab_interface

[Jürgen Groß]

On 17.12.19 21:53, Aditya Pakki wrote:
> gnttab_request_version() always sets the gnttab_interface variable
> and the assertions to check for empty gnttab_interface is unnecessary.
> The patch eliminates multiple such assertions.
> 
> Signed-off-by: Aditya Pakki <pakki001@umn.edu>

Pushed to xen/tip.git for-linus-5.5b


Juergen