Dave Hansen <[email protected]> writes: > diff -puN mm/migrate.c~migrate_pages-add-success-return mm/migrate.c > --- a/mm/migrate.c~migrate_pages-add-success-return 2020-08-18 > 11:36:51.284583183 -0700 > +++ b/mm/migrate.c 2020-08-18 11:36:51.295583183 -0700 > @@ -1432,6 +1432,7 @@ out: > * @mode: The migration mode that specifies the constraints for > * page migration, if any. > * @reason: The reason for page migration. > + * @nr_succeeded: The number of pages migrated successfully. > * > * The function returns after 10 attempts or if no pages are movable any more > * because the list has become empty or no retryable pages exist any more. > @@ -1442,11 +1443,10 @@ out: > */ > int migrate_pages(struct list_head *from, new_page_t get_new_page, > free_page_t put_new_page, unsigned long private, > - enum migrate_mode mode, int reason) > + enum migrate_mode mode, int reason, unsigned int *nr_succeeded) > { > int retry = 1; > int nr_failed = 0; > - int nr_succeeded = 0; > int pass = 0; > struct page *page; > struct page *page2; > @@ -1500,7 +1500,7 @@ retry: > retry++; > break; > case MIGRATEPAGE_SUCCESS: > - nr_succeeded++; > + (*nr_succeeded)++;
I think now we should consider THP in counting now. Because later nr_succeeded will be used to counting the number of reclaimed pages, and THP is respected for that. Best Regards, Huang, Ying > break; > default: > /* > @@ -1517,11 +1517,11 @@ retry: > nr_failed += retry; > rc = nr_failed; > out: > - if (nr_succeeded) > - count_vm_events(PGMIGRATE_SUCCESS, nr_succeeded); > + if (*nr_succeeded) > + count_vm_events(PGMIGRATE_SUCCESS, *nr_succeeded); > if (nr_failed) > count_vm_events(PGMIGRATE_FAIL, nr_failed); > - trace_mm_migrate_pages(nr_succeeded, nr_failed, mode, reason); > + trace_mm_migrate_pages(*nr_succeeded, nr_failed, mode, reason); > > if (!swapwrite) > current->flags &= ~PF_SWAPWRITE;
