[xen master] xen: Fold exit paths in find_text_region()

[patchbot@xxxxxxx]

commit b25607e528f6ce7851e907ed59ad5ff583aa1840
Author:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
AuthorDate: Thu Apr 13 19:52:10 2023 +0100
Commit:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
CommitDate: Thu Jan 18 22:52:54 2024 +0000

    xen: Fold exit paths in find_text_region()
    
    Despite rcu_read_unlock() being fully inlineable, the optimiser doesn't 
appear
    willing to fold the exit paths.  Rework the logic to do so explicitly.
    
    This compiles to marginally better code in all cases.  No functional change.
    
    Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
---
 xen/common/virtual_region.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/xen/common/virtual_region.c b/xen/common/virtual_region.c
index 5f89703f51..ddac5c9147 100644
--- a/xen/common/virtual_region.c
+++ b/xen/common/virtual_region.c
@@ -40,20 +40,20 @@ static DEFINE_RCU_READ_LOCK(rcu_virtual_region_lock);
 
 const struct virtual_region *find_text_region(unsigned long addr)
 {
-    const struct virtual_region *region;
+    const struct virtual_region *iter, *region = NULL;
 
     rcu_read_lock(&rcu_virtual_region_lock);
-    list_for_each_entry_rcu( region, &virtual_region_list, list )
+    list_for_each_entry_rcu ( iter, &virtual_region_list, list )
     {
-        if ( (void *)addr >= region->start && (void *)addr < region->end )
+        if ( (void *)addr >= iter->start && (void *)addr < iter->end )
         {
-            rcu_read_unlock(&rcu_virtual_region_lock);
-            return region;
+            region = iter;
+            break;
         }
     }
     rcu_read_unlock(&rcu_virtual_region_lock);
 
-    return NULL;
+    return region;
 }
 
 void register_virtual_region(struct virtual_region *r)
--
generated by git-patchbot for /home/xen/git/xen.git#master