powerpc: support for latencytop

Implement save_stack_trace_tsk on powerpc, so that we can run with
latencytop.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Arnd Bergmann 2008-07-11 00:08:18 +10:00 committed by Benjamin Herrenschmidt
parent 443dcac4d8
commit 01f4b8b8b8
2 changed files with 30 additions and 10 deletions

View File

@ -53,6 +53,9 @@ config STACKTRACE_SUPPORT
bool
default y
config HAVE_LATENCYTOP_SUPPORT
def_bool y
config TRACE_IRQFLAGS_SUPPORT
bool
depends on PPC64

View File

@ -10,33 +10,34 @@
* 2 of the License, or (at your option) any later version.
*/
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/stacktrace.h>
#include <asm/ptrace.h>
#include <asm/processor.h>
/*
* Save stack-backtrace addresses into a stack_trace buffer.
*/
void save_stack_trace(struct stack_trace *trace)
static void save_context_stack(struct stack_trace *trace, unsigned long sp,
struct task_struct *tsk, int savesched)
{
unsigned long sp;
asm("mr %0,1" : "=r" (sp));
for (;;) {
unsigned long *stack = (unsigned long *) sp;
unsigned long newsp, ip;
if (!validate_sp(sp, current, STACK_FRAME_OVERHEAD))
if (!validate_sp(sp, tsk, STACK_FRAME_OVERHEAD))
return;
newsp = stack[0];
ip = stack[STACK_FRAME_LR_SAVE];
if (savesched || !in_sched_functions(ip)) {
if (!trace->skip)
trace->entries[trace->nr_entries++] = ip;
else
trace->skip--;
}
if (trace->nr_entries >= trace->max_entries)
return;
@ -44,3 +45,19 @@ void save_stack_trace(struct stack_trace *trace)
sp = newsp;
}
}
void save_stack_trace(struct stack_trace *trace)
{
unsigned long sp;
asm("mr %0,1" : "=r" (sp));
save_context_stack(trace, sp, current, 1);
}
EXPORT_SYMBOL_GPL(save_stack_trace);
void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
{
save_context_stack(trace, tsk->thread.regs->gpr[1], tsk, 0);
}
EXPORT_SYMBOL_GPL(save_stack_trace_tsk);