Re: 2.6.8-rc3-mm2

William Lee Irwin III
2004-08-09T21:11:28Z

On Mon, Aug 09, 2004 at 12:17:50PM -0700, Jesse Barnes wrote:
>>> If I apply everything up to and including schedstat-v10.patch, it
>>> boots fine. So it might be sched-init_idle-fork_by_hand-consolidation.patch
>>> or something nearby... Just reverting the sched-single-array.patch
>>> wasn't enough.

On Mon, Aug 09, 2004 at 12:53:23PM -0700, William Lee Irwin III wrote:
>> I can reproduce here (ia64/Altix). Fixing.

On Mon, Aug 09, 2004 at 01:43:57PM -0700, William Lee Irwin III wrote:
> It comes up with the following applied. Now distilling into a bugfix.

The following does *NOT* come up. The difference appears to be the delay
from the printk()'s.

-- wli

--- mm2-2.6.8-rc3/arch/ia64/kernel/smpboot.c.orig 2004-08-10 05:24:20.000000000 -0700
+++ mm2-2.6.8-rc3/arch/ia64/kernel/smpboot.c 2004-08-10 06:50:21.774710311 -0700
@@ -356,44 +356,17 @@
return cpu_idle();
}

-struct create_idle {
- struct task_struct *idle;
- struct completion done;
- int cpu;
-};
-
-void
-do_fork_idle(void *_c_idle)
-{
- struct create_idle *c_idle = _c_idle;
-
- c_idle->idle = fork_idle(c_idle->cpu);
- complete(&c_idle->done);
-}
-
static int __devinit
do_boot_cpu (int sapicid, int cpu)
{
int timeout;
- struct create_idle c_idle = {
- .cpu = cpu,
- .done = COMPLETION_INITIALIZER(c_idle.done),
- };
- DECLARE_WORK(work, do_fork_idle, &c_idle);
/*
* We can't use kernel_thread since we must avoid to reschedule the child.
*/
- if (!keventd_up() || current_is_keventd())
- work.func(work.data);
- else {
- schedule_work(&work);
- wait_for_completion(&c_idle.done);
- }
-
- if (IS_ERR(c_idle.idle))
+ task_for_booting_cpu = fork_idle(cpu);
+ if (IS_ERR(task_for_booting_cpu))
panic("failed fork for CPU %d", cpu);
- task_for_booting_cpu = c_idle.idle;
-
+ mb();
Dprintk("Sending wakeup vector %lu to AP 0x%x/0x%x.\n", ap_wakeup_vector, cpu, sapicid);

platform_send_ipi(cpu, ap_wakeup_vector, IA64_IPI_DM_INT, 0);
--- mm2-2.6.8-rc3/kernel/fork.c.orig 2004-08-10 06:02:27.000000000 -0700
+++ mm2-2.6.8-rc3/kernel/fork.c 2004-08-10 06:03:11.000000000 -0700
@@ -1190,7 +1190,7 @@
goto fork_out;
}

-task_t * __init fork_idle(int cpu)
+task_t *fork_idle(int cpu)
{
task_t *task;
struct pt_regs regs;