69 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			69 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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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/export.h>
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| #include <linux/kprobes.h>
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| #include <linux/sched.h>
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| 
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| noinstr static
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| unsigned int check_preemption_disabled(const char *what1, const char *what2)
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| {
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| 	int this_cpu = raw_smp_processor_id();
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| 
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| 	if (likely(preempt_count()))
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| 		goto out;
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| 
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| 	if (irqs_disabled())
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| 		goto out;
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| 
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| 	if (is_percpu_thread())
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| 		goto out;
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| 
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| #ifdef CONFIG_SMP
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| 	if (current->migration_disabled)
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| 		goto out;
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| #endif
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| 
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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_SCHEDULING)
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| 		goto out;
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| 
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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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| 
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| 	instrumentation_begin();
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| 	if (!printk_ratelimit())
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| 		goto out_enable;
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| 
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| 	printk(KERN_ERR "BUG: using %s%s() in preemptible [%08x] code: %s/%d\n",
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| 		what1, what2, preempt_count() - 1, current->comm, current->pid);
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| 
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| 	printk("caller is %pS\n", __builtin_return_address(0));
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| 	dump_stack();
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| 	instrumentation_end();
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| 
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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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| 
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| noinstr unsigned int debug_smp_processor_id(void)
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| {
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| 	return check_preemption_disabled("smp_processor_id", "");
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| }
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| EXPORT_SYMBOL(debug_smp_processor_id);
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| 
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| noinstr void __this_cpu_preempt_check(const char *op)
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| {
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| 	check_preemption_disabled("__this_cpu_", op);
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| }
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| EXPORT_SYMBOL(__this_cpu_preempt_check);
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