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by Sebastien JAN
Initial Texas Instruments OMAP4 kernel for 2.6.34 |
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/*
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* lib/smp_processor_id.c
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*
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* DEBUG_PREEMPT variant of smp_processor_id().
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*/
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#include <linux/module.h> |
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#include <linux/kallsyms.h> |
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#include <linux/sched.h> |
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notrace unsigned int debug_smp_processor_id(void) |
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{
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unsigned long preempt_count = preempt_count(); |
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int this_cpu = raw_smp_processor_id(); |
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if (likely(preempt_count)) |
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goto out; |
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if (irqs_disabled()) |
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goto out; |
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/*
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* Kernel threads bound to a single CPU can safely use
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* smp_processor_id():
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*/
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if (cpumask_equal(¤t->cpus_allowed, cpumask_of(this_cpu))) |
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goto out; |
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/*
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* It is valid to assume CPU-locality during early bootup:
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*/
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if (system_state != SYSTEM_RUNNING) |
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goto out; |
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/*
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* Avoid recursion:
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*/
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preempt_disable_notrace(); |
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if (!printk_ratelimit()) |
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goto out_enable; |
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printk(KERN_ERR "BUG: using smp_processor_id() in preemptible [%08x] " |
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"code: %s/%d\n", |
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preempt_count() - 1, current->comm, current->pid); |
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print_symbol("caller is %s\n", (long)__builtin_return_address(0)); |
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dump_stack(); |
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out_enable: |
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preempt_enable_no_resched_notrace(); |
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out: |
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return this_cpu; |
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}
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EXPORT_SYMBOL(debug_smp_processor_id); |
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