2013-06-24 19:38:22

by Paul Gortmaker

[permalink] [raw]
Subject: [PATCH 16/32] cris: delete __cpuinit usage from all cris files

The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications. For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out. Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
are flagged as __cpuinit -- so if we remove the __cpuinit from
arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
content into no-ops as early as possible, since that will get rid
of these warnings. In any case, they are temporary and harmless.

This removes all the arch/cris uses of the __cpuinit macros from
all C files. Currently cris does not have any __CPUINIT used in
assembly files.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: Mikael Starvik <[email protected]>
Cc: Jesper Nilsson <[email protected]>
Cc: [email protected]
Signed-off-by: Paul Gortmaker <[email protected]>
---

[This commit is part of the __cpuinit removal work. If you don't see
any problems with it, then you don't have to do anything ; it will be
submitted with all the rest of the __cpuinit removal work. On the
other hand, if you want to carry this patch in with your other pending
changes so as to handle conflicts with other pending work yourself, then
that is fine too, as the commits can largely be treated independently.
For more information, please see: https://lkml.org/lkml/2013/6/20/513 ]

arch/cris/arch-v32/kernel/smp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/cris/arch-v32/kernel/smp.c b/arch/cris/arch-v32/kernel/smp.c
index cdd1202..fe8e603 100644
--- a/arch/cris/arch-v32/kernel/smp.c
+++ b/arch/cris/arch-v32/kernel/smp.c
@@ -197,7 +197,7 @@ int setup_profiling_timer(unsigned int multiplier)
*/
unsigned long cache_decay_ticks = 1;

-int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *tidle)
+int __cpu_up(unsigned int cpu, struct task_struct *tidle)
{
smp_boot_one_cpu(cpu, tidle);
return cpu_online(cpu) ? 0 : -ENOSYS;
--
1.8.1.2


2013-06-25 10:51:27

by Jesper Nilsson

[permalink] [raw]
Subject: Re: [PATCH 16/32] cris: delete __cpuinit usage from all cris files

On Mon, Jun 24, 2013 at 09:30:21PM +0200, Paul Gortmaker wrote:
> The __cpuinit type of throwaway sections might have made sense
> some time ago when RAM was more constrained, but now the savings
> do not offset the cost and complications. For example, the fix in
> commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
> is a good example of the nasty type of bugs that can be created
> with improper use of the various __init prefixes.
>
> After a discussion on LKML[1] it was decided that cpuinit should go
> the way of devinit and be phased out. Once all the users are gone,
> we can then finally remove the macros themselves from linux/init.h.
>
> Note that some harmless section mismatch warnings may result, since
> notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
> are flagged as __cpuinit -- so if we remove the __cpuinit from
> arch specific callers, we will also get section mismatch warnings.
> As an intermediate step, we intend to turn the linux/init.h cpuinit
> content into no-ops as early as possible, since that will get rid
> of these warnings. In any case, they are temporary and harmless.
>
> This removes all the arch/cris uses of the __cpuinit macros from
> all C files. Currently cris does not have any __CPUINIT used in
> assembly files.
>
> [1] https://lkml.org/lkml/2013/5/20/589
>
> Cc: Mikael Starvik <[email protected]>

Acked-by: Jesper Nilsson <[email protected]>

> Cc: [email protected]
> Signed-off-by: Paul Gortmaker <[email protected]>
> ---
>
> [This commit is part of the __cpuinit removal work. If you don't see
> any problems with it, then you don't have to do anything ; it will be
> submitted with all the rest of the __cpuinit removal work. On the
> other hand, if you want to carry this patch in with your other pending
> changes so as to handle conflicts with other pending work yourself, then
> that is fine too, as the commits can largely be treated independently.
> For more information, please see: https://lkml.org/lkml/2013/6/20/513 ]
>
> arch/cris/arch-v32/kernel/smp.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/cris/arch-v32/kernel/smp.c b/arch/cris/arch-v32/kernel/smp.c
> index cdd1202..fe8e603 100644
> --- a/arch/cris/arch-v32/kernel/smp.c
> +++ b/arch/cris/arch-v32/kernel/smp.c
> @@ -197,7 +197,7 @@ int setup_profiling_timer(unsigned int multiplier)
> */
> unsigned long cache_decay_ticks = 1;
>
> -int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *tidle)
> +int __cpu_up(unsigned int cpu, struct task_struct *tidle)
> {
> smp_boot_one_cpu(cpu, tidle);
> return cpu_online(cpu) ? 0 : -ENOSYS;
> --
> 1.8.1.2

/^JN - Jesper Nilsson
--
Jesper Nilsson -- [email protected]