From: Yu Zhao Date: Fri, 30 Apr 2021 06:01:04 +0000 (-0700) Subject: include/linux/page-flags-layout.h: correctly determine LAST_CPUPID_WIDTH X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=f73c6c8805ed0762d99122d5332fcf42b0c8fbb8;p=linux.git include/linux/page-flags-layout.h: correctly determine LAST_CPUPID_WIDTH The naming convention used in include/linux/page-flags-layout.h: *_SHIFT: the number of bits trying to allocate *_WIDTH: the number of bits successfully allocated So when it comes to LAST_CPUPID_WIDTH, we need to check whether all previous *_WIDTH and LAST_CPUPID_SHIFT can fit into page flags. This means we need to use NODES_WIDTH, not NODES_SHIFT. Link: https://lkml.kernel.org/r/20210303071609.797782-1-yuzhao@google.com Signed-off-by: Yu Zhao Cc: Matthew Wilcox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/include/linux/page-flags-layout.h b/include/linux/page-flags-layout.h index 7d4ec26d8a3ed..295c2c687d2ce 100644 --- a/include/linux/page-flags-layout.h +++ b/include/linux/page-flags-layout.h @@ -83,7 +83,7 @@ #define KASAN_TAG_WIDTH 0 #endif -#if SECTIONS_WIDTH+ZONES_WIDTH+NODES_SHIFT+LAST_CPUPID_SHIFT+KASAN_TAG_WIDTH \ +#if SECTIONS_WIDTH+ZONES_WIDTH+NODES_WIDTH+LAST_CPUPID_SHIFT+KASAN_TAG_WIDTH \ <= BITS_PER_LONG - NR_PAGEFLAGS #define LAST_CPUPID_WIDTH LAST_CPUPID_SHIFT #else