[PATCH 22/27] um, smpboot: Use generic SMP booting infrastructure

From: Srivatsa S. Bhat
Date: Fri Jun 01 2012 - 06:23:15 EST


From: Nikunj A. Dadhania <nikunj@xxxxxxxxxxxxxxxxxx>

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

Notes:
1. Removed call to default_idle() in idle_proc(). The generic framework will
invoke cpu_idle().
2. The generic code will call preempt_disable() and local_irq_enable() which
weren't originally present in idle_proc().

Signed-off-by: Nikunj A. Dadhania <nikunj@xxxxxxxxxxxxxxxxxx>
Cc: Jeff Dike <jdike@xxxxxxxxxxx>
Cc: Richard Weinberger <richard@xxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Cc: Chris Metcalf <cmetcalf@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: user-mode-linux-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: user-mode-linux-user@xxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@xxxxxxxxxxxxxxxxxx>
---

arch/um/kernel/smp.c | 12 +++++++-----
1 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/arch/um/kernel/smp.c b/arch/um/kernel/smp.c
index a02b7e9..6cffcf4 100644
--- a/arch/um/kernel/smp.c
+++ b/arch/um/kernel/smp.c
@@ -10,6 +10,7 @@
#ifdef CONFIG_SMP

#include "linux/sched.h"
+#include "linux/smpboot.h"
#include "linux/module.h"
#include "linux/threads.h"
#include "linux/interrupt.h"
@@ -58,6 +59,12 @@ static cpumask_t cpu_callin_map = CPU_MASK_NONE;

static int idle_proc(void *cpup)
{
+ smpboot_start_secondary(cpup);
+ return 0;
+}
+
+void __cpuinit __cpu_pre_starting(void *unused)
+{
int cpu = (int) cpup, err;

err = os_pipe(cpu_data[cpu].ipi_pipe, 1, 1);
@@ -74,11 +81,6 @@ static int idle_proc(void *cpup)

while (!cpu_isset(cpu, smp_commenced_mask))
cpu_relax();
-
- notify_cpu_starting(cpu);
- set_cpu_online(cpu, true);
- default_idle();
- return 0;
}

static struct task_struct *idle_thread(int cpu)

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/