GitHub-Mirror/Star64_linux
2
0
Fork 0
mirror of https://github.com/Fishwaldo/Star64_linux.git synced 2025-06-20 13:41:30 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

sched: Use lockdep-based checking on rcu_dereference()

Browse source 
Update the rcu_dereference() usages to take advantage of the new
lockdep-based checking.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference: <1266887105-1528-6-git-send-email-paulmck@linux.vnet.ibm.com>
[ -v2: fix allmodconfig missing symbol export build failure on x86 ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Paul E. McKenney 2010-02-22 17:04:50 -08:00 • committed by Ingo Molnar
parent a898def29e
commit d11c563dd2
9 changed files with 45 additions and 12 deletions
Download patch file Download diff file Expand all files Collapse all files

14
kernel/exit.c
View file

@ -85,7 +85,9 @@ static void __exit_signal(struct task_struct *tsk)
BUG_ON(!sig);
BUG_ON(!atomic_read(&sig->count));
sighand = rcu_dereference(tsk->sighand);
sighand = rcu_dereference_check(tsk->sighand,
rcu_read_lock_held() ||
lockdep_is_held(&tasklist_lock));
spin_lock(&sighand->siglock);
posix_cpu_timers_exit(tsk);
@ -170,8 +172,10 @@ void release_task(struct task_struct * p)
repeat:
tracehook_prepare_release_task(p);
/* don't need to get the RCU readlock here - the process is dead and
* can't be modifying its own credentials */
* can't be modifying its own credentials. But shut RCU-lockdep up */
rcu_read_lock();
atomic_dec(&__task_cred(p)->user->processes);
rcu_read_unlock();
proc_flush_task(p);
@ -473,9 +477,11 @@ static void close_files(struct files_struct * files)
/*
* It is safe to dereference the fd table without RCU or
* ->file_lock because this is the last reference to the
* files structure.
* files structure. But use RCU to shut RCU-lockdep up.
*/
rcu_read_lock();
fdt = files_fdtable(files);
rcu_read_unlock();
for (;;) {
unsigned long set;
i = j * __NFDBITS;
@ -521,10 +527,12 @@ void put_files_struct(struct files_struct *files)
* at the end of the RCU grace period. Otherwise,
* you can free files immediately.
*/
rcu_read_lock();
fdt = files_fdtable(files);
if (fdt != &files->fdtab)
kmem_cache_free(files_cachep, files);
free_fdtable(fdt);
rcu_read_unlock();
}
}