| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Mon, 22 Mar 2010 19:41:30 +0100
From: Oleg Nesterov <oleg@...hat.com>
To: Andrew Morton <akpm@...ux-foundation.org>
Cc: Alexey Dobriyan <adobriyan@...il.com>,
"Eric W. Biederman" <ebiederm@...ssion.com>,
Roland McGrath <roland@...hat.com>,
linux-kernel@...r.kernel.org
Subject: [PATCH -mm 1/3] proc: get_nr_threads() doesn't need ->siglock any
longer
Now that task->signal can't go away get_nr_threads() doesn't need
->siglock to read signal->count.
Also, make it inline, move into sched.h, and convert 2 other proc
users of signal->count to use this (now trivial) helper.
Henceforth get_nr_threads() is the only valid user of signal->count,
we are ready to turn it into "int nr_threads" or, perhaps, kill it.
Signed-off-by: Oleg Nesterov <oleg@...hat.com>
---
include/linux/sched.h | 5 +++++
fs/proc/array.c | 4 ++--
fs/proc/base.c | 12 ------------
3 files changed, 7 insertions(+), 14 deletions(-)
--- 34-rc1/include/linux/sched.h~PROC_1_GNT_DONT_USE_SIGLOCK 2010-03-22 16:35:43.000000000 +0100
+++ 34-rc1/include/linux/sched.h 2010-03-22 16:41:53.000000000 +0100
@@ -2148,6 +2148,11 @@ extern bool current_is_single_threaded(v
#define while_each_thread(g, t) \
while ((t = next_thread(t)) != g)
+static inline int get_nr_threads(struct task_struct *tsk)
+{
+ return atomic_read(&tsk->signal->count);
+}
+
/* de_thread depends on thread_group_leader not being a pid based check */
#define thread_group_leader(p) (p == p->group_leader)
--- 34-rc1/fs/proc/array.c~PROC_1_GNT_DONT_USE_SIGLOCK 2010-03-11 13:11:50.000000000 +0100
+++ 34-rc1/fs/proc/array.c 2010-03-22 17:04:44.000000000 +0100
@@ -269,7 +269,7 @@ static inline void task_sig(struct seq_f
shpending = p->signal->shared_pending.signal;
blocked = p->blocked;
collect_sigign_sigcatch(p, &ignored, &caught);
- num_threads = atomic_read(&p->signal->count);
+ num_threads = get_nr_threads(p);
rcu_read_lock(); /* FIXME: is this correct? */
qsize = atomic_read(&__task_cred(p)->user->sigpending);
rcu_read_unlock();
@@ -412,7 +412,7 @@ static int do_task_stat(struct seq_file
tty_nr = new_encode_dev(tty_devnum(sig->tty));
}
- num_threads = atomic_read(&sig->count);
+ num_threads = get_nr_threads(task);
collect_sigign_sigcatch(task, &sigign, &sigcatch);
cmin_flt = sig->cmin_flt;
--- 34-rc1/fs/proc/base.c~PROC_1_GNT_DONT_USE_SIGLOCK 2010-03-22 16:35:43.000000000 +0100
+++ 34-rc1/fs/proc/base.c 2010-03-22 16:36:28.000000000 +0100
@@ -165,18 +165,6 @@ static int get_fs_path(struct task_struc
return result;
}
-static int get_nr_threads(struct task_struct *tsk)
-{
- unsigned long flags;
- int count = 0;
-
- if (lock_task_sighand(tsk, &flags)) {
- count = atomic_read(&tsk->signal->count);
- unlock_task_sighand(tsk, &flags);
- }
- return count;
-}
-
static int proc_cwd_link(struct inode *inode, struct path *path)
{
struct task_struct *task = get_proc_task(inode);
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists