sched: Isolate preempt counting in its own config option

Create a new CONFIG_PREEMPT_COUNT that handles the inc/dec
of preempt count offset independently. So that the offset
can be updated by preempt_disable() and preempt_enable()
even without the need for CONFIG_PREEMPT beeing set.

This prepares to make CONFIG_DEBUG_SPINLOCK_SLEEP working
with !CONFIG_PREEMPT where it currently doesn't detect
code that sleeps inside explicit preemption disabled
sections.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
This commit is contained in:
Frederic Weisbecker 2011-06-08 01:13:27 +02:00
parent 2da8c8bc44
commit bdd4e85dc3
8 changed files with 33 additions and 22 deletions

View file

@ -93,7 +93,7 @@
*/
#define in_nmi() (preempt_count() & NMI_MASK)
#if defined(CONFIG_PREEMPT)
#if defined(CONFIG_PREEMPT_COUNT)
# define PREEMPT_CHECK_OFFSET 1
#else
# define PREEMPT_CHECK_OFFSET 0
@ -115,7 +115,7 @@
#define in_atomic_preempt_off() \
((preempt_count() & ~PREEMPT_ACTIVE) != PREEMPT_CHECK_OFFSET)
#ifdef CONFIG_PREEMPT
#ifdef CONFIG_PREEMPT_COUNT
# define preemptible() (preempt_count() == 0 && !irqs_disabled())
# define IRQ_EXIT_OFFSET (HARDIRQ_OFFSET-1)
#else