Re: [PATCH linux-next] ksm: add ksm involvement information for each process

[David Hildenbrand]

On 25.04.24 14:49, xu.xin16@xxxxxxxxxx wrote:
> From: xu xin <xu.xin16@xxxxxxxxxx>
>
> In /proc/<pid>/ksm_stat, Add two extra ksm involvement items including
> MMF_VM_MERGEABLE and MMF_VM_MERGE_ANY. It helps administrators to
> better know the system's KSM behavior at process level.
>
> MMF_VM_MERGEABLE: yes/no
> 	whether a process'mm is added by madvise() into the candidate list
> 	of KSM or not.
> MMF_VM_MERGE_ANY: yes/no
> 	whether a process'mm is added by prctl at process level into the
> candidate list of KSM or not.
>
> Signed-off-by: xu xin <xu.xin16@xxxxxxxxxx>
> ---
>   fs/proc/base.c | 4 ++++
>   1 file changed, 4 insertions(+)
>
> diff --git a/fs/proc/base.c b/fs/proc/base.c
> index 18550c071d71..421594b8510c 100644
> --- a/fs/proc/base.c
> +++ b/fs/proc/base.c
> @@ -3217,6 +3217,10 @@ static int proc_pid_ksm_stat(struct seq_file *m, struct pid_namespace *ns,
>   		seq_printf(m, "ksm_zero_pages %lu\n", mm->ksm_zero_pages);
>   		seq_printf(m, "ksm_merging_pages %lu\n", mm->ksm_merging_pages);
>   		seq_printf(m, "ksm_process_profit %ld\n", ksm_process_profit(mm));
> +		seq_printf(m, "MMF_VM_MERGEABLE: %s\n",
> +				test_bit(MMF_VM_MERGEABLE, &mm->flags) ? "yes" : "no");
> +		seq_printf(m, "MMF_VM_MERGE_ANY: %s\n",
> +				test_bit(MMF_VM_MERGE_ANY, &mm->flags) ? "yes" : "no");

Not sure if exposing these internal flag names is appropriate. Better 
describe what they do.

--
Cheers,

David / dhildenb