2007-09-25 18:24:52

by Bernhard Walle

[permalink] [raw]
Subject: [patch 5/7] Use extended crashkernel command line on ppc64

This patch adapts the ppc64 code to use the generic parse_crashkernel()
function introduced in the generic patch of that series.


Signed-off-by: Bernhard Walle <[email protected]>

---
arch/powerpc/kernel/machine_kexec.c | 52 ++++++++++++++++++------------------
1 file changed, 26 insertions(+), 26 deletions(-)

--- a/arch/powerpc/kernel/machine_kexec.c
+++ b/arch/powerpc/kernel/machine_kexec.c
@@ -61,45 +61,39 @@ NORET_TYPE void machine_kexec(struct kim
for(;;);
}

-static int __init early_parse_crashk(char *p)
+void __init reserve_crashkernel(void)
{
- unsigned long size;
-
- if (!p)
- return 1;
-
- size = memparse(p, &p);
+ unsigned long long crash_size, crash_base;
+ int ret;

- if (*p == '@')
- crashk_res.start = memparse(p + 1, &p);
- else
- crashk_res.start = KDUMP_KERNELBASE;
-
- crashk_res.end = crashk_res.start + size - 1;
-
- return 0;
-}
-early_param("crashkernel", early_parse_crashk);
+ /* this is necessary because of lmb_phys_mem_size() */
+ lmb_analyze();

-void __init reserve_crashkernel(void)
-{
- unsigned long size;
+ /* use common parsing */
+ ret = parse_crashkernel(boot_command_line, lmb_phys_mem_size(),
+ &crash_size, &crash_base);
+ if (ret == 0 && crash_size > 0) {
+ if (crash_base == 0)
+ crash_base = KDUMP_KERNELBASE;
+ crashk_res.start = crash_base;
+ } else {
+ /* handle the device tree */
+ crash_size = crashk_res.end - crashk_res.start + 1;
+ }

- if (crashk_res.start == 0)
+ if (crash_size == 0)
return;

/* We might have got these values via the command line or the
* device tree, either way sanitise them now. */

- size = crashk_res.end - crashk_res.start + 1;
-
if (crashk_res.start != KDUMP_KERNELBASE)
printk("Crash kernel location must be 0x%x\n",
KDUMP_KERNELBASE);

crashk_res.start = KDUMP_KERNELBASE;
- size = PAGE_ALIGN(size);
- crashk_res.end = crashk_res.start + size - 1;
+ crash_size = PAGE_ALIGN(crash_size);
+ crashk_res.end = crashk_res.start + crash_size - 1;

/* Crash kernel trumps memory limit */
if (memory_limit && memory_limit <= crashk_res.end) {
@@ -108,7 +102,13 @@ void __init reserve_crashkernel(void)
memory_limit);
}

- lmb_reserve(crashk_res.start, size);
+ printk(KERN_INFO "Reserving %ldMB of memory at %ldMB "
+ "for crashkernel (System RAM: %ldMB)\n",
+ (unsigned long)(crash_size >> 20),
+ (unsigned long)(crashk_res.start >> 20),
+ (unsigned long)(lmb_phys_mem_size() >> 20));
+
+ lmb_reserve(crashk_res.start, crash_size);
}

int overlaps_crashkernel(unsigned long start, unsigned long size)

--


2007-09-25 19:46:34

by Andrew Morton

[permalink] [raw]
Subject: Re: [patch 5/7] Use extended crashkernel command line on ppc64

On Tue, 25 Sep 2007 20:23:02 +0200 Bernhard Walle <[email protected]> wrote:

> This patch adapts the ppc64 code to use the generic parse_crashkernel()
> function introduced in the generic patch of that series.
>
>

I really don't like to see patches get a wholesale replacement, especially
when they've been looked at by a few people and have had some testing, etc.
It's not possible to see what changed and people need to re-review stuff
they've already reviewed, etc.

So I almost always undo this mess, turn the patches back into incremental
ones, see what pops out.

This patch is actually:


diff -puN arch/powerpc/kernel/machine_kexec.c~use-extended-crashkernel-command-line-on-ppc64-update arch/powerpc/kernel/machine_kexec.c
--- a/arch/powerpc/kernel/machine_kexec.c~use-extended-crashkernel-command-line-on-ppc64-update
+++ a/arch/powerpc/kernel/machine_kexec.c
@@ -63,7 +63,7 @@ NORET_TYPE void machine_kexec(struct kim

void __init reserve_crashkernel(void)
{
- unsigned long long crash_size = 0, crash_base;
+ unsigned long long crash_size, crash_base;
int ret;

/* this is necessary because of lmb_phys_mem_size() */
_


which I suspect will now create a compiler warning.


unsigned long long crash_size, crash_base;
int ret;

/* this is necessary because of lmb_phys_mem_size() */
lmb_analyze();

/* use common parsing */
ret = parse_crashkernel(boot_command_line, lmb_phys_mem_size(),
&crash_size, &crash_base);
if (ret == 0 && crash_size > 0) {
if (crash_base == 0)
crash_base = KDUMP_KERNELBASE;
crashk_res.start = crash_base;
} else {
/* handle the device tree */
crash_size = crashk_res.end - crashk_res.start + 1;
}

if (crash_size == 0)
return;

If so, the use of uninitialized_var() would be better than the unneeded
initialization-to-zero.

2007-09-26 08:15:52

by Bernhard Walle

[permalink] [raw]
Subject: Re: [patch 5/7] Use extended crashkernel command line on ppc64

Hi,

* Andrew Morton <[email protected]> [2007-09-25 21:45]:
> On Tue, 25 Sep 2007 20:23:02 +0200 Bernhard Walle <[email protected]> wrote:
>
> > This patch adapts the ppc64 code to use the generic parse_crashkernel()
> > function introduced in the generic patch of that series.
>
> I really don't like to see patches get a wholesale replacement, especially
> when they've been looked at by a few people and have had some testing, etc.
> It's not possible to see what changed and people need to re-review stuff
> they've already reviewed, etc.

Sorry, I didn't know that this is the preferred way. I just thought
it's more clear if the patches are replaced if the patch set is
finally pushed into Linus' tree.

> diff -puN arch/powerpc/kernel/machine_kexec.c~use-extended-crashkernel-command-line-on-ppc64-update arch/powerpc/kernel/machine_kexec.c
> --- a/arch/powerpc/kernel/machine_kexec.c~use-extended-crashkernel-command-line-on-ppc64-update
> +++ a/arch/powerpc/kernel/machine_kexec.c
> @@ -63,7 +63,7 @@ NORET_TYPE void machine_kexec(struct kim
>
> void __init reserve_crashkernel(void)
> {
> - unsigned long long crash_size = 0, crash_base;
> + unsigned long long crash_size, crash_base;
> int ret;
>
> /* this is necessary because of lmb_phys_mem_size() */
> _
>
>
> which I suspect will now create a compiler warning.

No, it doesn't. I just verified this.

CHK include/linux/compile.h
CC arch/powerpc/kernel/machine_kexec.o
LD arch/powerpc/kernel/built-in.o


Thanks,
Bernhard
--
Bernhard Walle <[email protected]>, Architecture Maintenance
SUSE LINUX Products GmbH, N?rnberg, Germany
GF: Markus Rex, HRB 16746 (AG N?rnberg)
OpenPGP: F61F 34CC 09CA FB82 C9F6 BA4B 8865 3696 DDAF 6454