Re: [PATCH v16 2/3] mm: memory-failure: move return value documentation to function declaration

Shuai Xue
2024-11-06T06:12:29Z

在 2024/11/5 23:18, Yazen Ghannam 写道:
> On Mon, Nov 04, 2024 at 09:54:29AM +0800, Shuai Xue wrote:
>> Part of return value comments for memory_failure() were originally
>> documented at the call site. Move those comments to the function
>> declaration to improve code readability and to provide developers with
>> immediate access to function usage and return information.
>>
>> Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
>> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
>> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
>> ---
>> arch/x86/kernel/cpu/mce/core.c | 7 -------
>> mm/memory-failure.c | 9 ++++++---
>> 2 files changed, 6 insertions(+), 10 deletions(-)
>>
>> diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
>> index 2a938f429c4d..c90d8fcd246a 100644
>> --- a/arch/x86/kernel/cpu/mce/core.c
>> +++ b/arch/x86/kernel/cpu/mce/core.c
>> @@ -1373,13 +1373,6 @@ static void kill_me_maybe(struct callback_head *cb)
>> return;
>> }
>>
>> - /*
>> - * -EHWPOISON from memory_failure() means that it already sent SIGBUS
>> - * to the current process with the proper error info,
>> - * -EOPNOTSUPP means hwpoison_filter() filtered the error event,
>> - *
>> - * In both cases, no further processing is required.
>> - */
>> if (ret == -EHWPOISON || ret == -EOPNOTSUPP)
>> return;
>>
>> diff --git a/mm/memory-failure.c b/mm/memory-failure.c
>> index 96ce31e5a203..1c5098f32d48 100644
>> --- a/mm/memory-failure.c
>> +++ b/mm/memory-failure.c
>> @@ -2209,9 +2209,12 @@ static void kill_procs_now(struct page *p, unsigned long pfn, int flags,
>> * Must run in process context (e.g. a work queue) with interrupts
>> * enabled and no spinlocks held.
>> *
>> - * Return: 0 for successfully handled the memory error,
>> - * -EOPNOTSUPP for hwpoison_filter() filtered the error event,
>> - * < 0(except -EOPNOTSUPP) on failure.
>> + * Return:
>> + * 0 - success,
>
> One more obvious one from this function:
>
> -ENXIO - memory not managed by the kernel

Yes, will fix it.

>
>> + * -EOPNOTSUPP - hwpoison_filter() filtered the error event,
>> + * -EHWPOISON - the page was already poisoned, potentially
>> + * kill process,
>> + * other negative values - failure.
>> */
>> int memory_failure(unsigned long pfn, int flags)
>> {
>> --
>
> Reviewed-by: Yazen Ghannam <yazen.ghannam@amd.com>
>
> Thanks,
> Yazen

Thank you for valuable comments.
Shuai