The patch titled Subject: proc: faster /proc/$PID lookup has been removed from the -mm tree. Its filename was proc-faster-proc-pid-lookup.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Alexey Dobriyan <adobriyan@xxxxxxxxx> Subject: proc: faster /proc/$PID lookup Currently lookup for /proc/$PID first goes through spinlock and whole list of misc /proc entries only to confirm that, yes, /proc/42 can not possibly match random proc entry. List is is several dozens entries long (52 entries on my setup). None of this is necessary. Try to convert dentry name to integer first. If it works, it must be /proc/$PID. If it doesn't, it must be random proc entry. Based on patch from Al Viro. Signed-off-by: Alexey Dobriyan <adobriyan@xxxxxxxxx> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/proc/base.c | 2 +- fs/proc/root.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff -puN fs/proc/base.c~proc-faster-proc-pid-lookup fs/proc/base.c --- a/fs/proc/base.c~proc-faster-proc-pid-lookup +++ a/fs/proc/base.c @@ -2780,7 +2780,7 @@ out: struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) { - int result = 0; + int result = -ENOENT; struct task_struct *task; unsigned tgid; struct pid_namespace *ns; diff -puN fs/proc/root.c~proc-faster-proc-pid-lookup fs/proc/root.c --- a/fs/proc/root.c~proc-faster-proc-pid-lookup +++ a/fs/proc/root.c @@ -199,10 +199,10 @@ static int proc_root_getattr(struct vfsm static struct dentry *proc_root_lookup(struct inode * dir, struct dentry * dentry, unsigned int flags) { - if (!proc_lookup(dir, dentry, flags)) + if (!proc_pid_lookup(dir, dentry, flags)) return NULL; - return proc_pid_lookup(dir, dentry, flags); + return proc_lookup(dir, dentry, flags); } static int proc_root_readdir(struct file *file, struct dir_context *ctx) _ Patches currently in -mm which might be from adobriyan@xxxxxxxxx are origin.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html