From: Liam R. Howlett <Liam.Howlett@oracle.com>
Date: Fri, 3 Sep 2021 15:15:33 +0000 (-0400)
Subject: mm_types: Optimize mm_struct alignments
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=54ea2f28c842eaabec52b96083a98f2151d665ce;p=users%2Fjedix%2Flinux-maple.git

mm_types: Optimize mm_struct alignments

There are three atomic_t which are of size 4.  This leaves a hole of 4
bytes on x86_64 according to pahole.  Move map_count to the first
cacheline to fill this hole.

Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
---

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 740715d5dad9..515d97a02882 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -512,11 +512,11 @@ struct mm_struct {
 		 * &struct mm_struct is freed.
 		 */
 		atomic_t mm_count;
+		int map_count;			/* number of VMAs */
 
 #ifdef CONFIG_MMU
 		atomic_long_t pgtables_bytes;	/* PTE page table pages */
 #endif
-		int map_count;			/* number of VMAs */
 
 		spinlock_t page_table_lock; /* Protects page tables and some
 					     * counters