svn commit: r335490 - head/sys/dev/xen/grant_table

[Roger Pau Monné]

Author: royger
Date: Thu Jun 21 15:47:47 2018
New Revision: 335490
URL: https://svnweb.freebsd.org/changeset/base/335490

Log:
  xen: check if there are clients waiting in gnttab_end_foreign_access_references
  
  Without a call to check_free_callbacks() clients waiting for grant
  references would not be woken up even when there are sufficient grant
  references available.
  
  The check was likely left out as a mistake when the function was first
  added.
  
  Note that other functions used to free grant references already call
  check_free_callbacks.
  
  Submitted by:		pratyush
  Reviewed by:		royger
  Differential review:	https://reviews.freebsd.org/D15899

Modified:
  head/sys/dev/xen/grant_table/grant_table.c

Modified: head/sys/dev/xen/grant_table/grant_table.c
==============================================================================
--- head/sys/dev/xen/grant_table/grant_table.c	Thu Jun 21 15:21:17 2018	(r335489)
+++ head/sys/dev/xen/grant_table/grant_table.c	Thu Jun 21 15:47:47 2018	(r335490)
@@ -245,6 +245,7 @@ gnttab_end_foreign_access_references(u_int count, gran
 		gnttab_free_count += count;
 		gnttab_entry(tail) = gnttab_free_head;
 		gnttab_free_head = head;
+		check_free_callbacks();
 		mtx_unlock(&gnttab_list_lock);
 	}
 }