I noticed that some lowlevel send_IPI_mask helpers had a hotplug/preempt race whereupon the cpu_online_map was read before disabling preemption; ... cpumask_t mask = cpu_online_map; int cpu = get_cpu(); cpu_clear(cpu, mask); ... But then i realised that there is no need for these lowlevel functions to be going through all this trouble when all the callers are already made hotplug/preempt safe. Signed-off-by: Zwane Mwaikambo <zwane@arm.linux.org.uk> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
		
			
				
	
	
		
			51 lines
		
	
	
	
		
			1.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			51 lines
		
	
	
	
		
			1.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
#ifndef __ASM_MACH_IPI_H
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#define __ASM_MACH_IPI_H
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void send_IPI_mask_bitmask(cpumask_t mask, int vector);
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void __send_IPI_shortcut(unsigned int shortcut, int vector);
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extern int no_broadcast;
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static inline void send_IPI_mask(cpumask_t mask, int vector)
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{
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	send_IPI_mask_bitmask(mask, vector);
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}
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static inline void __local_send_IPI_allbutself(int vector)
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{
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	if (no_broadcast) {
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		cpumask_t mask = cpu_online_map;
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		cpu_clear(smp_processor_id(), mask);
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		send_IPI_mask(mask, vector);
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	} else
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		__send_IPI_shortcut(APIC_DEST_ALLBUT, vector);
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}
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static inline void __local_send_IPI_all(int vector)
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{
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	if (no_broadcast)
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		send_IPI_mask(cpu_online_map, vector);
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	else
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		__send_IPI_shortcut(APIC_DEST_ALLINC, vector);
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}
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static inline void send_IPI_allbutself(int vector)
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{
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	/*
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	 * if there are no other CPUs in the system then we get an APIC send 
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	 * error if we try to broadcast, thus avoid sending IPIs in this case.
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	 */
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	if (!(num_online_cpus() > 1))
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		return;
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	__local_send_IPI_allbutself(vector);
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	return;
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}
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static inline void send_IPI_all(int vector)
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{
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	__local_send_IPI_all(vector);
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}
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#endif /* __ASM_MACH_IPI_H */
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