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Revision 6a0596583fadd15dca293736114abdea306d3d7c authored by Linus Torvalds on 24 October 2011, 05:08:24 UTC, committed by Linus Torvalds on 24 October 2011, 05:08:24 UTC 
Merge git://git.infradead.org/iommu-2.6
 
* git://git.infradead.org/iommu-2.6:
  intel-iommu: fix superpage support in pfn_to_dma_pte()
  intel-iommu: set iommu_superpage on VM domains to lowest common denominator
  intel-iommu: fix return value of iommu_unmap() API
  MAINTAINERS: Update VT-d entry for drivers/pci -> drivers/iommu move
  intel-iommu: Export a flag indicating that the IOMMU is used for iGFX.
  intel-iommu: Workaround IOTLB hang on Ironlake GPU
  intel-iommu: Fix AB-BA lockdep report
2 parent s 15cc910 + 4399c8b
Raw File
smp_processor_id.c 
/*
 * lib/smp_processor_id.c
 *
 * DEBUG_PREEMPT variant of smp_processor_id().
 */
#include <linux/module.h>
#include <linux/kallsyms.h>
#include <linux/sched.h>

notrace unsigned int debug_smp_processor_id(void)
{
	unsigned long preempt_count = preempt_count();
	int this_cpu = raw_smp_processor_id();

	if (likely(preempt_count))
		goto out;

	if (irqs_disabled())
		goto out;

	/*
	 * Kernel threads bound to a single CPU can safely use
	 * smp_processor_id():
	 */
	if (cpumask_equal(&current->cpus_allowed, cpumask_of(this_cpu)))
		goto out;

	/*
	 * It is valid to assume CPU-locality during early bootup:
	 */
	if (system_state != SYSTEM_RUNNING)
		goto out;

	/*
	 * Avoid recursion:
	 */
	preempt_disable_notrace();

	if (!printk_ratelimit())
		goto out_enable;

	printk(KERN_ERR "BUG: using smp_processor_id() in preemptible [%08x] "
			"code: %s/%d\n",
			preempt_count() - 1, current->comm, current->pid);
	print_symbol("caller is %s\n", (long)__builtin_return_address(0));
	dump_stack();

out_enable:
	preempt_enable_no_resched_notrace();
out:
	return this_cpu;
}

EXPORT_SYMBOL(debug_smp_processor_id);
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