From: Chris Caputo <[email protected]>
[PATCH 2.6.19-rc6] sched: cleanup output of show_state/show_task
This patch cleans up the output of show_state/task() (aka magic-sysrq-t)
so that free stack space is printed as appropriate based on
CONFIG_DEBUG_STACK_USAGE.
Also, without this patch the header is not aligned with the data and is
thus confusing. Free stack is labeled as pid, pid is labeled as father,
and so on.
Signed-off-by: Chris Caputo <[email protected]>
---
diff -uprN a/kernel/sched.c b/kernel/sched.c
--- a/kernel/sched.c 2006-11-25 04:11:12.000000000 +0000
+++ b/kernel/sched.c 2006-11-25 04:13:07.000000000 +0000
@@ -4757,7 +4757,6 @@ static const char stat_nam[] = "RSDTtZX"
static void show_task(struct task_struct *p)
{
struct task_struct *relative;
- unsigned long free = 0;
unsigned state;
state = p->state ? __ffs(p->state) + 1 : 0;
@@ -4779,10 +4778,10 @@ static void show_task(struct task_struct
unsigned long *n = end_of_stack(p);
while (!*n)
n++;
- free = (unsigned long)n - (unsigned long)end_of_stack(p);
+ printk("%5lu ", (unsigned long)n - (unsigned long)end_of_stack(p));
}
#endif
- printk("%5lu %5d %6d ", free, p->pid, p->parent->pid);
+ printk("%5d %6d ", p->pid, p->parent->pid);
if ((relative = eldest_child(p)))
printk("%5d ", relative->pid);
else
@@ -4808,14 +4807,18 @@ void show_state(void)
{
struct task_struct *g, *p;
-#if (BITS_PER_LONG == 32)
+#ifdef CONFIG_DEBUG_STACK_USAGE
printk("\n"
- " sibling\n");
- printk(" task PC pid father child younger older\n");
+ " %s free sibling\n",
+ BITS_PER_LONG == 32 ? " " : " ");
+ printk(" task %s stack pid father child younger older\n",
+ BITS_PER_LONG == 32 ? " PC " : " PC ");
#else
printk("\n"
- " sibling\n");
- printk(" task PC pid father child younger older\n");
+ " %s sibling\n",
+ BITS_PER_LONG == 32 ? " " : " ");
+ printk(" task %s pid father child younger older\n",
+ BITS_PER_LONG == 32 ? " PC " : " PC ");
#endif
read_lock(&tasklist_lock);
do_each_thread(g, p) {
On Sat, 25 Nov 2006 04:48:15 +0000 (GMT)
Chris Caputo <[email protected]> wrote:
>
> This patch cleans up the output of show_state/task() (aka magic-sysrq-t)
> so that free stack space is printed as appropriate based on
> CONFIG_DEBUG_STACK_USAGE.
>
> Also, without this patch the header is not aligned with the data and is
> thus confusing. Free stack is labeled as pid, pid is labeled as father,
> and so on.
>
> Signed-off-by: Chris Caputo <[email protected]>
> ---
>
> diff -uprN a/kernel/sched.c b/kernel/sched.c
> --- a/kernel/sched.c 2006-11-25 04:11:12.000000000 +0000
> +++ b/kernel/sched.c 2006-11-25 04:13:07.000000000 +0000
> @@ -4757,7 +4757,6 @@ static const char stat_nam[] = "RSDTtZX"
> static void show_task(struct task_struct *p)
> {
> struct task_struct *relative;
> - unsigned long free = 0;
> unsigned state;
>
> state = p->state ? __ffs(p->state) + 1 : 0;
> @@ -4779,10 +4778,10 @@ static void show_task(struct task_struct
> unsigned long *n = end_of_stack(p);
> while (!*n)
> n++;
> - free = (unsigned long)n - (unsigned long)end_of_stack(p);
> + printk("%5lu ", (unsigned long)n - (unsigned long)end_of_stack(p));
> }
> #endif
> - printk("%5lu %5d %6d ", free, p->pid, p->parent->pid);
> + printk("%5d %6d ", p->pid, p->parent->pid);
This will cause the output format to be dependent upon the setting of
CONFIG_DEBUG_STACK_USAGE. So any code which attempts to parse the output
of this function will somehow need to work out whether or not the `free'
field is present.
Which is why we still print out a zero if CONFIG_DEBUG_STACK_USAGE=n.
On Mon, 27 Nov 2006, Andrew Morton wrote:
> On Sat, 25 Nov 2006 04:48:15 +0000 (GMT)
> Chris Caputo <[email protected]> wrote:
> > This patch cleans up the output of show_state/task() (aka magic-sysrq-t)
> > so that free stack space is printed as appropriate based on
> > CONFIG_DEBUG_STACK_USAGE.
> >
> > Also, without this patch the header is not aligned with the data and is
> > thus confusing. Free stack is labeled as pid, pid is labeled as father,
> > and so on.
> >
> > Signed-off-by: Chris Caputo <[email protected]>
> > ---
> >
> > diff -uprN a/kernel/sched.c b/kernel/sched.c
> > --- a/kernel/sched.c 2006-11-25 04:11:12.000000000 +0000
> > +++ b/kernel/sched.c 2006-11-25 04:13:07.000000000 +0000
> > @@ -4757,7 +4757,6 @@ static const char stat_nam[] = "RSDTtZX"
> > static void show_task(struct task_struct *p)
> > {
> > struct task_struct *relative;
> > - unsigned long free = 0;
> > unsigned state;
> >
> > state = p->state ? __ffs(p->state) + 1 : 0;
> > @@ -4779,10 +4778,10 @@ static void show_task(struct task_struct
> > unsigned long *n = end_of_stack(p);
> > while (!*n)
> > n++;
> > - free = (unsigned long)n - (unsigned long)end_of_stack(p);
> > + printk("%5lu ", (unsigned long)n - (unsigned long)end_of_stack(p));
> > }
> > #endif
> > - printk("%5lu %5d %6d ", free, p->pid, p->parent->pid);
> > + printk("%5d %6d ", p->pid, p->parent->pid);
>
> This will cause the output format to be dependent upon the setting of
> CONFIG_DEBUG_STACK_USAGE. So any code which attempts to parse the output
> of this function will somehow need to work out whether or not the `free'
> field is present.
>
> Which is why we still print out a zero if CONFIG_DEBUG_STACK_USAGE=n.
Ahh!
Should we make it so the header printed by show_state is aligned properly
with the data? If yes, please consider the below patch.
Chris
---
From: Chris Caputo <[email protected]>
[PATCH 2.6.19-rc6] sched: correct output of show_state
At present show_state prints a header the does not match the output of
show_task, as follows:
-
sibling
task PC pid father child younger older
init S 00000000 0 1 0 2 (NOTLB)
-
This patch corrects the output of show_state so that the header is
aligned with the data, ala:
-
free sibling
task PC stack pid father child younger older
init S 00000000 0 1 0 2 (NOTLB)
-
Signed-off-by: Chris Caputo <[email protected]>
---
--- a/kernel/sched.c 2006-11-27 08:40:56.000000000 +0000
+++ b/kernel/sched.c 2006-11-27 23:23:49.000000000 +0000
@@ -4810,12 +4810,12 @@ void show_state(void)
#if (BITS_PER_LONG == 32)
printk("\n"
- " sibling\n");
- printk(" task PC pid father child younger older\n");
+ " free sibling\n");
+ printk(" task PC stack pid father child younger older\n");
#else
printk("\n"
- " sibling\n");
- printk(" task PC pid father child younger older\n");
+ " free sibling\n");
+ printk(" task PC stack pid father child younger older\n");
#endif
read_lock(&tasklist_lock);
do_each_thread(g, p) {