@@ -48,7 +48,7 @@ extern void set_smp_ipi_range(int ipi_base, int nr_ipi);
* Called from platform specific assembly code, this is the
* secondary CPU entry point.
*/
-asmlinkage void secondary_start_kernel(unsigned int cpu);
+asmlinkage void secondary_start_kernel(unsigned int cpu, struct task_struct *task);
/*
@@ -62,6 +62,7 @@ struct secondary_data {
unsigned long swapper_pg_dir;
void *stack;
unsigned int cpu;
+ struct task_struct *task;
};
extern struct secondary_data secondary_data;
extern void secondary_startup(void);
@@ -115,6 +115,7 @@ ENTRY(secondary_startup)
ret r12
1: bl __after_proc_init
ldr r0, [r7, #16] @ set up cpu number
+ ldr r1, [r7, #20] @ set up task pointer
ldr sp, [r7, #12] @ set up the stack pointer
mov fp, #0
b secondary_start_kernel
@@ -395,6 +395,7 @@ ENDPROC(secondary_startup_arm)
ENTRY(__secondary_switched)
ldr_l r7, secondary_data + 12 @ get secondary_data.stack
ldr_l r0, secondary_data + 16 @ get secondary_data.cpu
+ ldr_l r1, secondary_data + 20 @ get secondary_data.task
mov sp, r7
mov fp, #0
b secondary_start_kernel
@@ -154,6 +154,7 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle)
secondary_data.swapper_pg_dir = get_arch_pgd(swapper_pg_dir);
#endif
secondary_data.cpu = cpu;
+ secondary_data.task = idle;
sync_cache_w(&secondary_data);
/*
@@ -375,13 +376,14 @@ void arch_cpu_idle_dead(void)
* to be repeated to undo the effects of taking the CPU offline.
*/
__asm__("mov r0, %1\n"
+ " mov r1, %2\n"
" mov sp, %0\n"
" mov fp, #0\n"
" b secondary_start_kernel"
:
: "r" (task_stack_page(current) + THREAD_SIZE - 8),
- "r" (cpu)
- : "r0");
+ "r" (cpu), "r" (current)
+ : "r0", "r1");
}
#endif /* CONFIG_HOTPLUG_CPU */
@@ -404,7 +406,7 @@ static void smp_store_cpu_info(unsigned int cpuid)
* This is the secondary CPU boot entry. We're using this CPUs
* idle thread stack, but a set of temporary page tables.
*/
-asmlinkage void secondary_start_kernel(unsigned int cpu)
+asmlinkage void secondary_start_kernel(unsigned int cpu, struct task_struct *task)
{
struct mm_struct *mm = &init_mm;
This avoids needing to compute the task pointer in this function, allowing it to be used as the source of identification in the future. Signed-off-by: Keith Packard <keithpac@amazon.com> --- arch/arm/include/asm/smp.h | 3 ++- arch/arm/kernel/head-nommu.S | 1 + arch/arm/kernel/head.S | 1 + arch/arm/kernel/smp.c | 8 +++++--- 4 files changed, 9 insertions(+), 4 deletions(-)