Construct init thread stack in the linker script rather than by union

Construct the init thread stack in the linker script rather than doing it
by means of a union so that ia64's init_task.c can be got rid of.

The following symbols are then made available from INIT_TASK_DATA() linker
script macro:

	init_thread_union
	init_stack

INIT_TASK_DATA() also expands the region to THREAD_SIZE to accommodate the
size of the init stack.  init_thread_union is given its own section so that
it can be placed into the stack space in the right order.  I'm assuming
that the ia64 ordering is correct and that the task_struct is first and the
thread_info second.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Tony Luck <tony.luck@intel.com>
Tested-by: Will Deacon <will.deacon@arm.com> (arm64)
Tested-by: Palmer Dabbelt <palmer@sifive.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
David Howells 2018-01-02 15:12:01 +00:00
parent 1381019320
commit 0500871f21
50 changed files with 42 additions and 155 deletions

View file

@ -1446,12 +1446,21 @@ extern void ia64_set_curr_task(int cpu, struct task_struct *p);
void yield(void);
union thread_union {
#ifndef CONFIG_ARCH_TASK_STRUCT_ON_STACK
struct task_struct task;
#endif
#ifndef CONFIG_THREAD_INFO_IN_TASK
struct thread_info thread_info;
#endif
unsigned long stack[THREAD_SIZE/sizeof(long)];
};
#ifndef CONFIG_THREAD_INFO_IN_TASK
extern struct thread_info init_thread_info;
#endif
extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)];
#ifdef CONFIG_THREAD_INFO_IN_TASK
static inline struct thread_info *task_thread_info(struct task_struct *task)
{