Re: [PATCH] LoongArch: Let cores_io_master cover the largest NR_CPUS

[maobibo]

On 2023/12/25 下午10:02, Jiaxun Yang wrote:
> 在 2023/12/25 09:19, Huacai Chen 写道:
> > On Mon, Dec 25, 2023 at 5:13 PM maobibo <maobibo@xxxxxxxxxxx> wrote:
> > > On 2023/12/25 下午3:00, Huacai Chen wrote:
> > > > Now loongson_system_configuration::cores_io_master only covers 64 cpus,
> > > > if NR_CPUS > 64 there will be memory corruption. So let cores_io_master
> > > > cover the largest NR_CPUS (256).
> > > >
> > > > Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx>
> > > > ---
> > > >    arch/loongarch/include/asm/bootinfo.h | 4 ++--
> > > >    arch/loongarch/kernel/acpi.c          | 2 +-
> > > >    arch/loongarch/kernel/smp.c           | 2 +-
> > > >    3 files changed, 4 insertions(+), 4 deletions(-)
> > > >
> > > > diff --git a/arch/loongarch/include/asm/bootinfo.h 
> > > > b/arch/loongarch/include/asm/bootinfo.h
> > > > index c60796869b2b..32fd0319594a 100644
> > > > --- a/arch/loongarch/include/asm/bootinfo.h
> > > > +++ b/arch/loongarch/include/asm/bootinfo.h
> > > > @@ -30,7 +30,7 @@ struct loongson_system_configuration {
> > > >        int boot_cpu_id;
> > > >        int cores_per_node;
> > > >        int cores_per_package;
> > > > -     unsigned long cores_io_master;
> > > > +     unsigned long cores_io_master[4];
> > > Can the hardcoded 4 be defined something like this?
> > >      DIV_ROUND_UP(CONFIG_NR_CPUS, sizeof(long))
> > Can this be used to define arrays?
>
> I think DECLARE_BITMAP should work.
>
> See how are we dealing with cpumask_t:
> ```
> typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
> ```
Yeap, that will be better.

Regards
Bibo Mao
> Thanks
> - Jiaxun
> [...]
>
> > Huacai