pahole showed that struct audit_watch had two holes: struct audit_watch { atomic_t count; /* 0 4 */ /* XXX 4 bytes hole, try to pack */ char * path; /* 8 8 */ dev_t dev; /* 16 4 */ /* XXX 4 bytes hole, try to pack */ long unsigned int ino; /* 24 8 */ struct audit_parent * parent; /* 32 8 */ struct list_head wlist; /* 40 16 */ struct list_head rules; /* 56 16 */ /* --- cacheline 1 boundary (64 bytes) was 8 bytes ago --- */ /* size: 72, cachelines: 2, members: 7 */ /* sum members: 64, holes: 2, sum holes: 8 */ /* last cacheline: 8 bytes */ }; /* definitions: 1 */ by moving dev after count we save 8 bytes, actually improving cacheline usage. There are typically very few of these in the kernel so it won't be a large savings, but it's a good thing no matter what. Signed-off-by: Eric Paris <eparis(a)redhat.com&gt; --- kernel/audit_watch.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c index cfaa248..aa8babc 100644 --- a/kernel/audit_watch.c +++ b/kernel/audit_watch.c @@ -45,8 +45,8 @@ struct audit_watch { atomic_t count; /* reference count */ - char *path; /* insertion path */ dev_t dev; /* associated superblock device */ + char *path; /* insertion path */ unsigned long ino; /* associated inode number */ struct audit_parent *parent; /* associated parent */ struct list_head wlist; /* entry in parent->watches list */