lkml.org 
[lkml]   [2015]   [Sep]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 3.16.y-ckt 050/130] MIPS: Fix sched_getaffinity with MT FPAFF enabled
Date
3.16.7-ckt17 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Felix Fietkau <nbd@openwrt.org>

commit 1d62d737555e1378eb62a8bba26644f7d97139d2 upstream.

p->thread.user_cpus_allowed is zero-initialized and is only filled on
the first sched_setaffinity call.

To avoid adding overhead in the task initialization codepath, simply OR
the returned mask in sched_getaffinity with p->cpus_allowed.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10740/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
---
arch/mips/kernel/mips-mt-fpaff.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/mips/kernel/mips-mt-fpaff.c b/arch/mips/kernel/mips-mt-fpaff.c
index 362bb3707e62..116c67a5320a 100644
--- a/arch/mips/kernel/mips-mt-fpaff.c
+++ b/arch/mips/kernel/mips-mt-fpaff.c
@@ -154,7 +154,7 @@ asmlinkage long mipsmt_sys_sched_getaffinity(pid_t pid, unsigned int len,
unsigned long __user *user_mask_ptr)
{
unsigned int real_len;
- cpumask_t mask;
+ cpumask_t allowed, mask;
int retval;
struct task_struct *p;

@@ -173,7 +173,8 @@ asmlinkage long mipsmt_sys_sched_getaffinity(pid_t pid, unsigned int len,
if (retval)
goto out_unlock;

- cpumask_and(&mask, &p->thread.user_cpus_allowed, cpu_possible_mask);
+ cpumask_or(&allowed, &p->thread.user_cpus_allowed, &p->cpus_allowed);
+ cpumask_and(&mask, &allowed, cpu_active_mask);

out_unlock:
read_unlock(&tasklist_lock);

\
 
 \ /
  Last update: 2015-09-04 16:01    [W:0.346 / U:0.132 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site