From 4f1134370a29a5f2d0f4b4be4c5e2fddd38f0f9d Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Tue, 10 Apr 2018 16:32:20 -0700 Subject: proc: use slower rb_first() In a typical for /proc "open+read+close" usecase, dentry is looked up successfully on open only to be killed in dput() on close. In fact dentries which aren't /proc/*/... and /proc/sys/* were almost NEVER CACHED. Simple printk in proc_lookup_de() shows that. Now that ->delete hook intelligently picks which dentries should live in dcache and which should not, rbtree caching is not necessary as dcache does it job, at last! As a side effect, struct proc_dir_entry shrinks by one pointer which can go into inline name. Link: http://lkml.kernel.org/r/20180314231032.GA15854@avx2 Signed-off-by: Alexey Dobriyan Acked-by: Davidlohr Bueso Cc: Peter Zijlstra Cc: Al Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/proc/internal.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'fs/proc/internal.h') diff --git a/fs/proc/internal.h b/fs/proc/internal.h index b7024f174778..0f1692e63cb6 100644 --- a/fs/proc/internal.h +++ b/fs/proc/internal.h @@ -51,15 +51,15 @@ struct proc_dir_entry { kgid_t gid; loff_t size; struct proc_dir_entry *parent; - struct rb_root_cached subdir; + struct rb_root subdir; struct rb_node subdir_node; char *name; umode_t mode; u8 namelen; #ifdef CONFIG_64BIT -#define SIZEOF_PDE_INLINE_NAME (192-147) +#define SIZEOF_PDE_INLINE_NAME (192-139) #else -#define SIZEOF_PDE_INLINE_NAME (128-91) +#define SIZEOF_PDE_INLINE_NAME (128-87) #endif char inline_name[SIZEOF_PDE_INLINE_NAME]; } __randomize_layout; -- cgit v1.2.3