Commit 8eece07c authored by Alexei Starovoitov's avatar Alexei Starovoitov
Browse files

Merge tag 'sched-for-bpf-2020-02-20' of... 

Merge tag 'sched-for-bpf-2020-02-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into bpf-next

Two migrate disable related stubs for BPF to base the RT patches on
parents 732a0dee 4e139c77

include/linux/kernel.h

+7 −0
Original line number Diff line number Diff line
@@ -257,6 +257,13 @@ extern void __cant_sleep(const char *file, int line, int preempt_offset); 


#define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)



#ifndef CONFIG_PREEMPT_RT

# define cant_migrate()		cant_sleep()

#else

  /* Placeholder for now */

# define cant_migrate()		do { } while (0)

#endif



/**

 * abs - return absolute value of an argument

 * @x: the value.  If it is unsigned type, it is converted to signed type first.

include/linux/preempt.h

+30 −0
Original line number Diff line number Diff line
@@ -322,4 +322,34 @@ static inline void preempt_notifier_init(struct preempt_notifier *notifier, 


#endif



/**

 * migrate_disable - Prevent migration of the current task

 *

 * Maps to preempt_disable() which also disables preemption. Use

 * migrate_disable() to annotate that the intent is to prevent migration,

 * but not necessarily preemption.

 *

 * Can be invoked nested like preempt_disable() and needs the corresponding

 * number of migrate_enable() invocations.

 */

static __always_inline void migrate_disable(void)

{

	preempt_disable();

}



/**

 * migrate_enable - Allow migration of the current task

 *

 * Counterpart to migrate_disable().

 *

 * As migrate_disable() can be invoked nested, only the outermost invocation

 * reenables migration.

 *

 * Currently mapped to preempt_enable().

 */

static __always_inline void migrate_enable(void)

{

	preempt_enable();

}



#endif /* __LINUX_PREEMPT_H */