On 30.12.22 02:16, yang.yang29@xxxxxxxxxx wrote:
From: xu xin <xu.xin16@xxxxxxxxxx> As the number of ksm zero pages is not included in ksm_merging_pages per process when enabling use_zero_pages, it's unclear of how many actual pages are merged by KSM. To let users accurately estimate their memory demands when unsharing KSM zero-pages, it's necessary to show KSM zero- pages per process. since unsharing zero pages placed by KSM accurately is achieved, then tracking empty pages merging and unmerging is not a difficult thing any longer. Since we already have /proc/<pid>/ksm_stat, just add the information of zero_pages_sharing in it. Cc: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: Xuexin Jiang <jiang.xuexin@xxxxxxxxxx> Cc: Xiaokai Ran <ran.xiaokai@xxxxxxxxxx> Cc: Yang Yang <yang.yang29@xxxxxxxxxx> Signed-off-by: xu xin <xu.xin16@xxxxxxxxxx> --- fs/proc/base.c | 1 + include/linux/mm_types.h | 7 ++++++- mm/ksm.c | 2 ++ 3 files changed, 9 insertions(+), 1 deletion(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index 9e479d7d202b..ac9ebe972be0 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -3207,6 +3207,7 @@ static int proc_pid_ksm_stat(struct seq_file *m, struct pid_namespace *ns, mm = get_task_mm(task); if (mm) { seq_printf(m, "ksm_rmap_items %lu\n", mm->ksm_rmap_items); + seq_printf(m, "zero_pages_sharing %lu\n", mm->ksm_zero_pages_sharing); mmput(mm); } diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 4e1031626403..5c734ebc1890 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -776,7 +776,7 @@ struct mm_struct { #ifdef CONFIG_KSM /* * Represent how many pages of this process are involved in KSM - * merging. + * merging (not including ksm_zero_pages_sharing). */ unsigned long ksm_merging_pages; /* @@ -784,6 +784,11 @@ struct mm_struct { * including merged and not merged. */ unsigned long ksm_rmap_items; + /* + * Represent how many empty pages are merged with kernel zero + * pages when enabling KSM use_zero_pages. + */ + unsigned long ksm_zero_pages_sharing;
Same comment as for previous patch: this counts rmap itmaps, no? ksm_zero_rmap_items might be more appropriate.
-- Thanks, David / dhildenb