From 202e35db5e719ee8af6028183403f475e243f82d Mon Sep 17 00:00:00 2001 From: Dave Hansen Date: Tue, 4 May 2021 18:36:04 -0700 Subject: mm/vmscan: replace implicit RECLAIM_ZONE checks with explicit checks RECLAIM_ZONE was assumed to be unused because it was never explicitly used in the kernel. However, there were a number of places where it was checked implicitly by checking 'node_reclaim_mode' for a zero value. These zero checks are not great because it is not obvious what a zero mode *means* in the code. Replace them with a helper which makes it more obvious: node_reclaim_enabled(). This helper also provides a handy place to explicitly check the RECLAIM_ZONE bit itself. Check it explicitly there to make it more obvious where the bit can affect behavior. This should have no functional impact. Link: https://lkml.kernel.org/r/20210219172559.BF589C44@viggo.jf.intel.com Signed-off-by: Dave Hansen Reviewed-by: Ben Widawsky Reviewed-by: Oscar Salvador Acked-by: Christoph Lameter Acked-by: David Rientjes Cc: Alex Shi Cc: "Tobin C. Harding" Cc: Huang Ying Cc: Dan Williams Cc: Qian Cai Cc: Daniel Wagner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/swap.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include/linux') diff --git a/include/linux/swap.h b/include/linux/swap.h index 4cc6ec3bf0ab..42191da1bdc9 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -12,6 +12,7 @@ #include #include #include +#include #include struct notifier_block; @@ -378,6 +379,12 @@ extern int sysctl_min_slab_ratio; #define node_reclaim_mode 0 #endif +static inline bool node_reclaim_enabled(void) +{ + /* Is any node_reclaim_mode bit set? */ + return node_reclaim_mode & (RECLAIM_ZONE|RECLAIM_WRITE|RECLAIM_UNMAP); +} + extern void check_move_unevictable_pages(struct pagevec *pvec); extern int kswapd_run(int nid); -- cgit v1.2.3-59-g8ed1b