On 2024/4/10 17:38, Oscar Salvador wrote: > On Mon, Apr 08, 2024 at 08:42:21PM +0100, Matthew Wilcox (Oracle) wrote: >> The only user of this function calls page_address_in_vma() immediately >> after page_mapped_in_vma() calculates it and uses it to return true/false. >> Return the address instead, allowing memory-failure to skip the call >> to page_address_in_vma(). >> >> Acked-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> >> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> >> --- >> mm/page_vma_mapped.c | 14 ++++++++------ >> 1 file changed, 8 insertions(+), 6 deletions(-) >> >> diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c >> index 53b8868ede61..48bfc17934cd 100644 >> --- a/mm/page_vma_mapped.c >> +++ b/mm/page_vma_mapped.c >> @@ -319,9 +319,10 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) >> * @page: the page to test >> * @vma: the VMA to test >> * >> - * Returns 1 if the page is mapped into the page tables of the VMA, 0 >> - * if the page is not mapped into the page tables of this VMA. Only >> - * valid for normal file or anonymous VMAs. >> + * Return: The address the page is mapped at if the page is in the range >> + * covered by the VMA and present in the page table. If the page is >> + * outside the VMA or not present, returns -EFAULT. >> + * Only valid for normal file or anonymous VMAs. > > I am probably missing something here but I am confused. > Now we either return -EFAULT or the address. > > But page_vma_mapped_walk() gets called from collect_procs_anon() like > this: > > if (!page_mapped_in_vma(page, vma)) > > so that is not gonna work the way we want? > Should not that be converted to > > if (page_mapped_in_vma(page, vma) == -EFAULT) > > ? It seems this patch is incomplete. It forgets to change the caller parts as it once did at [1]. Or am I miss something too? [1] https://www.spinics.net/lists/linux-mm/msg375668.html Thanks. . >
