Subject: [PATCH] Change cpu_up and co from __devinit to __cpuinit

Compiling the kernel with CONFIG_HOTPLUG = y and CONFIG_HOTPLUG_CPU = n
with CONFIG_RELOCATABLE = y generates the following modpost warnings

WARNING: vmlinux - Section mismatch: reference to .init.data: from
.text between '_cpu_up' (at offset 0xc0141b7d) and 'cpu_up'
WARNING: vmlinux - Section mismatch: reference to .init.data: from
.text between '_cpu_up' (at offset 0xc0141b9c) and 'cpu_up'
WARNING: vmlinux - Section mismatch: reference to .init.text:__cpu_up
from .text between '_cpu_up' (at offset 0xc0141bd8) and 'cpu_up'
WARNING: vmlinux - Section mismatch: reference to .init.data: from
.text between '_cpu_up' (at offset 0xc0141c05) and 'cpu_up'
WARNING: vmlinux - Section mismatch: reference to .init.data: from
.text between '_cpu_up' (at offset 0xc0141c26) and 'cpu_up'
WARNING: vmlinux - Section mismatch: reference to .init.data: from
.text between '_cpu_up' (at offset 0xc0141c37) and 'cpu_up'

This is because cpu_up, _cpu_up and __cpu_up (in some architectures) are
defined as __devinit
AND
__cpu_up calls some __cpuinit functions.

Since __cpuinit would map to __init with this kind of a configuration,
we get a .text refering .init.data warning.

This patch solves the problem by converting all of __cpu_up, _cpu_up
and cpu_up from __devinit to __cpuinit. The approach is justified since
the callers of cpu_up are either dependent on CONFIG_HOTPLUG_CPU or
are of __init type.

Thus when CONFIG_HOTPLUG_CPU=y, all these cpu up functions would land up
in .text section, and when CONFIG_HOTPLUG_CPU=n, all these functions would
land up in .init section.

Tested on a i386 SMP machine running linux-2.6.20-rc3-mm1.

Signed-off-by: Gautham R Shenoy <[email protected]>
Cc: Vivek Goyal <[email protected]>
--
arch/cris/arch-v32/kernel/smp.c | 2 +-
arch/m32r/kernel/smpboot.c | 2 +-
arch/mips/kernel/smp.c | 2 +-
arch/parisc/kernel/smp.c | 2 +-
arch/powerpc/kernel/smp.c | 2 +-
arch/sparc64/kernel/smp.c | 2 +-
kernel/cpu.c | 4 ++--
7 files changed, 8 insertions(+), 8 deletions(-)

Index: linux-2.6.20-rc3/kernel/cpu.c
===================================================================
--- linux-2.6.20-rc3.orig/kernel/cpu.c
+++ linux-2.6.20-rc3/kernel/cpu.c
@@ -210,7 +210,7 @@ int cpu_down(unsigned int cpu)
#endif /*CONFIG_HOTPLUG_CPU*/

/* Requires cpu_add_remove_lock to be held */
-static int __devinit _cpu_up(unsigned int cpu)
+static int __cpuinit _cpu_up(unsigned int cpu)
{
int ret, nr_calls = 0;
void *hcpu = (void *)(long)cpu;
@@ -248,7 +248,7 @@ out_notify:
return ret;
}

-int __devinit cpu_up(unsigned int cpu)
+int __cpuinit cpu_up(unsigned int cpu)
{
int err = 0;

Index: linux-2.6.20-rc3/arch/cris/arch-v32/kernel/smp.c
===================================================================
--- linux-2.6.20-rc3.orig/arch/cris/arch-v32/kernel/smp.c
+++ linux-2.6.20-rc3/arch/cris/arch-v32/kernel/smp.c
@@ -195,7 +195,7 @@ int setup_profiling_timer(unsigned int m
*/
unsigned long cache_decay_ticks = 1;

-int __devinit __cpu_up(unsigned int cpu)
+int __cpuinit __cpu_up(unsigned int cpu)
{
smp_boot_one_cpu(cpu);
return cpu_online(cpu) ? 0 : -ENOSYS;
Index: linux-2.6.20-rc3/arch/powerpc/kernel/smp.c
===================================================================
--- linux-2.6.20-rc3.orig/arch/powerpc/kernel/smp.c
+++ linux-2.6.20-rc3/arch/powerpc/kernel/smp.c
@@ -468,7 +468,7 @@ static int __devinit cpu_enable(unsigned
return -ENOSYS;
}

-int __devinit __cpu_up(unsigned int cpu)
+int __cpuinit __cpu_up(unsigned int cpu)
{
int c;

Index: linux-2.6.20-rc3/arch/m32r/kernel/smpboot.c
===================================================================
--- linux-2.6.20-rc3.orig/arch/m32r/kernel/smpboot.c
+++ linux-2.6.20-rc3/arch/m32r/kernel/smpboot.c
@@ -351,7 +351,7 @@ static void __init do_boot_cpu(int phys_
}
}

-int __devinit __cpu_up(unsigned int cpu_id)
+int __cpuinit __cpu_up(unsigned int cpu_id)
{
int timeout;

Index: linux-2.6.20-rc3/arch/mips/kernel/smp.c
===================================================================
--- linux-2.6.20-rc3.orig/arch/mips/kernel/smp.c
+++ linux-2.6.20-rc3/arch/mips/kernel/smp.c
@@ -271,7 +271,7 @@ void __devinit smp_prepare_boot_cpu(void
* and keep control until "cpu_online(cpu)" is set. Note: cpu is
* physical, not logical.
*/
-int __devinit __cpu_up(unsigned int cpu)
+int __cpuinit __cpu_up(unsigned int cpu)
{
struct task_struct *idle;

Index: linux-2.6.20-rc3/arch/parisc/kernel/smp.c
===================================================================
--- linux-2.6.20-rc3.orig/arch/parisc/kernel/smp.c
+++ linux-2.6.20-rc3/arch/parisc/kernel/smp.c
@@ -608,7 +608,7 @@ void smp_cpus_done(unsigned int cpu_max)
}


-int __devinit __cpu_up(unsigned int cpu)
+int __cpuinit __cpu_up(unsigned int cpu)
{
if (cpu != 0 && cpu < parisc_max_cpus)
smp_boot_one_cpu(cpu);
Index: linux-2.6.20-rc3/arch/sparc64/kernel/smp.c
===================================================================
--- linux-2.6.20-rc3.orig/arch/sparc64/kernel/smp.c
+++ linux-2.6.20-rc3/arch/sparc64/kernel/smp.c
@@ -1388,7 +1388,7 @@ void __devinit smp_prepare_boot_cpu(void
{
}

-int __devinit __cpu_up(unsigned int cpu)
+int __cpuinit __cpu_up(unsigned int cpu)
{
int ret = smp_boot_one_cpu(cpu);




2007-01-08 22:45:42

by Andrew Morton

[permalink] [raw]
Subject: Re: [PATCH] Change cpu_up and co from __devinit to __cpuinit

On Sat, 6 Jan 2007 09:39:07 -0500
Gautham R Shenoy <[email protected]> wrote:

> Compiling the kernel with CONFIG_HOTPLUG = y and CONFIG_HOTPLUG_CPU = n
> with CONFIG_RELOCATABLE = y generates the following modpost warnings
>
> WARNING: vmlinux - Section mismatch: reference to .init.data: from
> .text between '_cpu_up' (at offset 0xc0141b7d) and 'cpu_up'
> WARNING: vmlinux - Section mismatch: reference to .init.data: from
> .text between '_cpu_up' (at offset 0xc0141b9c) and 'cpu_up'
> WARNING: vmlinux - Section mismatch: reference to .init.text:__cpu_up
> from .text between '_cpu_up' (at offset 0xc0141bd8) and 'cpu_up'
> WARNING: vmlinux - Section mismatch: reference to .init.data: from
> .text between '_cpu_up' (at offset 0xc0141c05) and 'cpu_up'
> WARNING: vmlinux - Section mismatch: reference to .init.data: from
> .text between '_cpu_up' (at offset 0xc0141c26) and 'cpu_up'
> WARNING: vmlinux - Section mismatch: reference to .init.data: from
> .text between '_cpu_up' (at offset 0xc0141c37) and 'cpu_up'

I suppose we should treat this as a 2.6.20 bugfix.

> --- linux-2.6.20-rc3.orig/kernel/cpu.c
> +++ linux-2.6.20-rc3/kernel/cpu.c
> @@ -210,7 +210,7 @@ int cpu_down(unsigned int cpu)
> #endif /*CONFIG_HOTPLUG_CPU*/
>
> /* Requires cpu_add_remove_lock to be held */
> -static int __devinit _cpu_up(unsigned int cpu)
> +static int __cpuinit _cpu_up(unsigned int cpu)
> {

Well that's new. space-stuffed emails are common enough, but you've worked
out how to do space-double-stuffing.