sched/preempt, MIPS: Properly lock access to the FPU

Let's always disable preemption and pagefaults when locking the fpu,
so we can be sure that the owner won't change in between.

This is a preparation for pagefault_disable() not touching preemption
anymore.

Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: airlied@linux.ie
Cc: akpm@linux-foundation.org
Cc: benh@kernel.crashing.org
Cc: bigeasy@linutronix.de
Cc: borntraeger@de.ibm.com
Cc: daniel.vetter@intel.com
Cc: heiko.carstens@de.ibm.com
Cc: herbert@gondor.apana.org.au
Cc: hocko@suse.cz
Cc: hughd@google.com
Cc: mst@redhat.com
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: schwidefsky@de.ibm.com
Cc: yang.shi@windriver.com
Link: http://lkml.kernel.org/r/1431359540-32227-15-git-send-email-dahi@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
David Hildenbrand 2015-05-11 17:52:19 +02:00 committed by Ingo Molnar
parent 5f76eea88d
commit 76deabd186

View File

@ -28,12 +28,7 @@ extern void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs,
extern int fpcsr_pending(unsigned int __user *fpcsr);
/* Make sure we will not lose FPU ownership */
#ifdef CONFIG_PREEMPT
#define lock_fpu_owner() preempt_disable()
#define unlock_fpu_owner() preempt_enable()
#else
#define lock_fpu_owner() pagefault_disable()
#define unlock_fpu_owner() pagefault_enable()
#endif
#define lock_fpu_owner() ({ preempt_disable(); pagefault_disable(); })
#define unlock_fpu_owner() ({ pagefault_enable(); preempt_enable(); })
#endif /* __SIGNAL_COMMON_H */