On Mon, Feb 10, 2020 at 02:00:39PM -0800, John Hubbard wrote: > On 2/10/20 1:54 PM, Kirill A. Shutemov wrote: > > On Mon, Feb 10, 2020 at 01:33:22PM -0800, John Hubbard wrote: > >>> PageSlab() can be called for the head page. > >> > >> > >> It's not clear to me whether it's safer to use the...user-provided page, or the > >> head page, for checking PageSlab()--it's probably set on both head and non-head > >> pages, right? > > > > PageSlab() will call compound_head() inside. > > > >> I guess you're saying it should be like this: > >> > >> mapcount = PageSlab(head) ? 0 : page_mapcount(page); > >> > >> ...yes? > > > > Yes. > > > > OK very good, thanks for walking me through it. :) > > Matthew, if you like I'll just fix it up like that for my v6 posting of the > patchset, since it's such a small change. Yes, please just fix it up.
