| Message ID | 20200831201402.2837-1-dave@stgolabs.net (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | f0100c7f1aac7f10eb249c494de5016fcf8c0652 |
| Headers | show |
| Series | MIPS: Use rcu to lookup a task in mipsmt_sys_sched_setaffinity() | expand |
On Mon, Aug 31, 2020 at 01:14:02PM -0700, Davidlohr Bueso wrote: > The call simply looks up the corresponding task (without iterating > the tasklist), which is safe under rcu instead of the tasklist_lock. > In addition, the setaffinity counter part already does this. > > Signed-off-by: Davidlohr Bueso <dbueso@suse.de> > --- > arch/mips/kernel/mips-mt-fpaff.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) applied to mips-next. Thomas.
diff --git a/arch/mips/kernel/mips-mt-fpaff.c b/arch/mips/kernel/mips-mt-fpaff.c index 1a08428eedcf..6c590ef27648 100644 --- a/arch/mips/kernel/mips-mt-fpaff.c +++ b/arch/mips/kernel/mips-mt-fpaff.c @@ -167,7 +167,7 @@ asmlinkage long mipsmt_sys_sched_getaffinity(pid_t pid, unsigned int len, return -EINVAL; get_online_cpus(); - read_lock(&tasklist_lock); + rcu_read_lock(); retval = -ESRCH; p = find_process_by_pid(pid); @@ -181,7 +181,7 @@ asmlinkage long mipsmt_sys_sched_getaffinity(pid_t pid, unsigned int len, cpumask_and(&mask, &allowed, cpu_active_mask); out_unlock: - read_unlock(&tasklist_lock); + rcu_read_unlock(); put_online_cpus(); if (retval) return retval;
The call simply looks up the corresponding task (without iterating the tasklist), which is safe under rcu instead of the tasklist_lock. In addition, the setaffinity counter part already does this. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> --- arch/mips/kernel/mips-mt-fpaff.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)