From 454cc105ef690f2a0ba7c6b194d55666b4e918ce Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Mon, 26 Jun 2006 00:25:51 -0700 Subject: [PATCH] [PATCH] proc: Remove tasklist_lock from proc_pid_readdir We don't need the tasklist_lock to safely iterate through processes anymore. This depends on my previous to task patches that make get_task_struct rcu safe, and that make next_task() rcu safe. I haven't gotten first_tid/next_tid yet only because next_thread is missing an rcu_dereference. Signed-off-by: Eric W. Biederman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/proc/base.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index 2236f7d3878e..cc578a300a2b 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -2043,7 +2043,7 @@ out: static struct task_struct *first_tgid(int tgid, int nr) { struct task_struct *pos = NULL; - read_lock(&tasklist_lock); + rcu_read_lock(); if (tgid && nr) { pos = find_task_by_pid(tgid); if (pos && !thread_group_leader(pos)) @@ -2069,7 +2069,7 @@ static struct task_struct *first_tgid(int tgid, int nr) } pos = NULL; done: - read_unlock(&tasklist_lock); + rcu_read_unlock(); return pos; } @@ -2082,7 +2082,7 @@ done: static struct task_struct *next_tgid(struct task_struct *start) { struct task_struct *pos; - read_lock(&tasklist_lock); + rcu_read_lock(); pos = start; if (pid_alive(start)) pos = next_task(start); @@ -2092,7 +2092,7 @@ static struct task_struct *next_tgid(struct task_struct *start) } pos = NULL; done: - read_unlock(&tasklist_lock); + rcu_read_unlock(); put_task_struct(start); return pos; }