On Mon, Nov 04, 2019 at 07:32:51PM -0800, Matthew Wilcox wrote: >On Tue, Nov 05, 2019 at 10:26:44AM +0800, Wei Yang wrote: >> Hi, All, >> >> I am curious about the semantic of __count_vm_event[s]. >> >> For example, we count PGDEACTIVATE event in lru_deactivate_file_fn() and >> lru_deactivate_fn(). One of them count with number of page, the other not. >> >> Just curious about the exact value we want to count. > >I don't understand the question. We deactivate one page >in lru_deactivate_file_fn(). We deactivate several pages in >shrink_active_list(). PGDEACTIVATE counts the number of pages which >have been deactivated. > >Does that answer your question? Not yet. In function, lru_deactivate_fn(), __count_vm_events's second parameter is hpage_nr_pages(page). This is the number in size of "normal" page. Per my understanding, the page deactivated in lru_deactivate_file_fn() could be a hpage too. But it just count the deactivation once instead of hpage_nr_pages(). Or you want to say the page deactivated in lru_deactivate_file_fn() must be an order 0 page? -- Wei Yang Help you, Help me
