[PATCH 26/27] arm, smpboot: Use generic SMP booting infrastructure

Srivatsa S. Bhat srivatsa.bhat at linux.vnet.ibm.com
Fri Jun 1 05:16:20 EDT 2012


Convert arm to use the generic framework to boot secondary CPUs.

Notes:
The calls to local_irq_enable() and local_fiq_enable() which were there
in secondary_start_kernel() originally, are retained in __cpu_post_online()
since the generic code only calls local_irq_enable().
Also, we were anyway going to enable interrupts in the generic code
immediately after __cpu_post_online(), so its not like we enabled interrupts
way too early.

Cc: Russell King <linux at arm.linux.org.uk>
Cc: Marc Zyngier <marc.zyngier at arm.com>
Cc: Will Deacon <will.deacon at arm.com>
Cc: Thomas Gleixner <tglx at linutronix.de>
Cc: David Brown <davidb at codeaurora.org>
Cc: linux-arm-kernel at lists.infradead.org
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat at linux.vnet.ibm.com>
---

 arch/arm/kernel/smp.c |   26 +++++++++++++-------------
 1 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index b735521..460b7e7 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -25,6 +25,7 @@
 #include <linux/percpu.h>
 #include <linux/clockchips.h>
 #include <linux/completion.h>
+#include <linux/smpboot.h>
 
 #include <linux/atomic.h>
 #include <asm/cacheflush.h>
@@ -227,6 +228,11 @@ static void percpu_timer_setup(void);
  */
 asmlinkage void __cpuinit secondary_start_kernel(void)
 {
+	smpboot_start_secondary(NULL);
+}
+
+void __cpuinit __cpu_pre_starting(void *unused)
+{
 	struct mm_struct *mm = &init_mm;
 	unsigned int cpu = smp_processor_id();
 
@@ -244,26 +250,25 @@ asmlinkage void __cpuinit secondary_start_kernel(void)
 	printk("CPU%u: Booted secondary processor\n", cpu);
 
 	cpu_init();
-	preempt_disable();
 	trace_hardirqs_off();
 
 	/*
 	 * Give the platform a chance to do its own initialisation.
 	 */
 	platform_secondary_init(cpu);
+}
 
-	notify_cpu_starting(cpu);
+void __cpuinit __cpu_pre_online(void *unused)
+{
+	unsigned int cpu = smp_processor_id();
 
 	calibrate_delay();
 
 	smp_store_cpu_info(cpu);
+}
 
-	/*
-	 * OK, now it's safe to let the boot CPU continue.  Wait for
-	 * the CPU migration code to notice that the CPU is online
-	 * before we continue - which happens after __cpu_up returns.
-	 */
-	set_cpu_online(cpu, true);
+void __cpuinit __cpu_post_online(void *unused)
+{
 	complete(&cpu_running);
 
 	/*
@@ -273,11 +278,6 @@ asmlinkage void __cpuinit secondary_start_kernel(void)
 
 	local_irq_enable();
 	local_fiq_enable();
-
-	/*
-	 * OK, it's off to the idle thread for us
-	 */
-	cpu_idle();
 }
 
 void __init smp_cpus_done(unsigned int max_cpus)




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