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Commit cb0cd8d4 authored by Ashok Raj's avatar Ashok Raj Committed by Linus Torvalds
Browse files

[PATCH] x86_64: CPU hotplug sibling map cleanup 



This patch is a minor cleanup to the cpu sibling/core map.  It is required
that this setup happens on a per-cpu bringup time.

Signed-off-by: default avatarAshok Raj <ashok.raj@intel.com>
Acked-by: default avatarAndi Kleen <ak@muc.de>
Acked-by: default avatarZwane Mwaikambo <zwane@arm.linux.org.uk>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 76e4f660

arch/x86_64/kernel/smpboot.c

+36 −48
Original line number Diff line number Diff line
@@ -445,6 +445,33 @@ void __cpuinit smp_callin(void) 
	cpu_set(cpuid, cpu_callin_map);

}



static inline void set_cpu_sibling_map(int cpu)

{

	int i;



	if (smp_num_siblings > 1) {

		for_each_cpu(i) {

			if (cpu_core_id[cpu] == cpu_core_id[i]) {

				cpu_set(i, cpu_sibling_map[cpu]);

				cpu_set(cpu, cpu_sibling_map[i]);

			}

		}

	} else {

		cpu_set(cpu, cpu_sibling_map[cpu]);

	}



	if (current_cpu_data.x86_num_cores > 1) {

		for_each_cpu(i) {

			if (phys_proc_id[cpu] == phys_proc_id[i]) {

				cpu_set(i, cpu_core_map[cpu]);

				cpu_set(cpu, cpu_core_map[i]);

			}

		}

	} else {

		cpu_core_map[cpu] = cpu_sibling_map[cpu];

	}

}



/*

 * Setup code on secondary processor (after comming out of the trampoline)

 */
@@ -474,6 +501,12 @@ void __cpuinit start_secondary(void) 


	enable_APIC_timer();



	/*

	 * The sibling maps must be set before turing the online map on for

	 * this cpu

	 */

	set_cpu_sibling_map(smp_processor_id());



	/*

	 * Allow the master to continue.

	 */
@@ -816,51 +849,6 @@ static int __cpuinit do_boot_cpu(int cpu, int apicid) 
cycles_t cacheflush_time;

unsigned long cache_decay_ticks;



/*

 * Construct cpu_sibling_map[], so that we can tell the sibling CPU

 * on SMT systems efficiently.

 */

static __cpuinit void detect_siblings(void)

{

	int cpu;



	for (cpu = 0; cpu < NR_CPUS; cpu++) {

		cpus_clear(cpu_sibling_map[cpu]);

		cpus_clear(cpu_core_map[cpu]);

	}



	for_each_online_cpu (cpu) {

		struct cpuinfo_x86 *c = cpu_data + cpu;

		int siblings = 0;

		int i;

		if (smp_num_siblings > 1) {

			for_each_online_cpu (i) {

				if (cpu_core_id[cpu] == cpu_core_id[i]) {

					siblings++;

					cpu_set(i, cpu_sibling_map[cpu]);

				}

			}

		} else {

			siblings++;

			cpu_set(cpu, cpu_sibling_map[cpu]);

		}



		if (siblings != smp_num_siblings) {

			printk(KERN_WARNING

	       "WARNING: %d siblings found for CPU%d, should be %d\n",

			       siblings, cpu, smp_num_siblings);

			smp_num_siblings = siblings;

		}

		if (c->x86_num_cores > 1) {

			for_each_online_cpu(i) {

				if (phys_proc_id[cpu] == phys_proc_id[i])

					cpu_set(i, cpu_core_map[cpu]);

			}

		} else

			cpu_core_map[cpu] = cpu_sibling_map[cpu];

	}

}



/*

 * Cleanup possible dangling ends...

 */
@@ -1048,6 +1036,8 @@ void __init smp_prepare_boot_cpu(void) 
	int me = smp_processor_id();

	cpu_set(me, cpu_online_map);

	cpu_set(me, cpu_callout_map);

	cpu_set(0, cpu_sibling_map[0]);

	cpu_set(0, cpu_core_map[0]);

}



/*
@@ -1107,7 +1097,6 @@ void __init smp_cpus_done(unsigned int max_cpus) 
	setup_ioapic_dest();

#endif



	detect_siblings();

	time_init_gtod();



	check_nmi_watchdog();
@@ -1115,8 +1104,7 @@ void __init smp_cpus_done(unsigned int max_cpus) 


#ifdef CONFIG_HOTPLUG_CPU



static void

remove_siblinginfo(int cpu)

static void remove_siblinginfo(int cpu)

{

	int sibling;