> On Mar 3, 2022, at 1:29 PM, Johannes Weiner <hannes@xxxxxxxxxxx> wrote: > > MADV_DONTNEED historically rejects mlocked ranges, but with > MLOCK_ONFAULT and MCL_ONFAULT allowing to mlock without populating, > there are valid use cases for depopulating locked ranges as well. ... > @@ -850,7 +858,7 @@ static long madvise_dontneed_free(struct vm_area_struct *vma, > VM_WARN_ON(start >= end); > } > > - if (behavior == MADV_DONTNEED) > + if (behavior == MADV_DONTNEED || behavior == MADV_DONTNEED_LOCKED) > return madvise_dontneed_single_vma(vma, start, end); > else if (behavior == MADV_FREE) > return madvise_free_single_vma(vma, start, end); > @@ -988,6 +996,7 @@ static int madvise_vma_behavior(struct vm_area_struct *vma, > return madvise_pageout(vma, prev, start, end); > case MADV_FREE: > case MADV_DONTNEED: > + case MADV_DONTNEED_LOCKED: > return madvise_dontneed_free(vma, prev, start, end, behavior); > case MADV_POPULATE_READ: > case MADV_POPULATE_WRITE: > @@ -1113,6 +1122,7 @@ madvise_behavior_valid(int behavior) > case MADV_REMOVE: > case MADV_WILLNEED: > case MADV_DONTNEED: > + case MADV_DONTNEED_LOCKED: > case MADV_FREE: > case MADV_COLD: > case MADV_PAGEOUT: Don’t you want to change madvise_need_mmap_write() as well and add MADV_DONTNEED_LOCKED there too?
