From: Charan Teja Kalla <quic_charante@xxxxxxxxxxx> Subject: mm: compaction: fix compiler warning when CONFIG_COMPACTION=n The below warning is reported when CONFIG_COMPACTION=n: mm/compaction.c:56:27: warning: 'HPAGE_FRAG_CHECK_INTERVAL_MSEC' defined but not used [-Wunused-const-variable=] 56 | static const unsigned int HPAGE_FRAG_CHECK_INTERVAL_MSEC = 500; | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fix it by moving 'HPAGE_FRAG_CHECK_INTERVAL_MSEC' under CONFIG_COMPACTION defconfig. Also since this is just a 'static const int' type, use #define for it. Link: https://lkml.kernel.org/r/1647608518-20924-1-git-send-email-quic_charante@xxxxxxxxxxx Signed-off-by: Charan Teja Kalla <quic_charante@xxxxxxxxxxx> Reported-by: kernel test robot <lkp@xxxxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Cc: Nitin Gupta <nigupta@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/compaction.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) --- a/mm/compaction.c~mm-compaction-fix-compiler-warning-when-config_compaction=n +++ a/mm/compaction.c @@ -26,6 +26,11 @@ #include "internal.h" #ifdef CONFIG_COMPACTION +/* + * Fragmentation score check interval for proactive compaction purposes. + */ +#define HPAGE_FRAG_CHECK_INTERVAL_MSEC (500) + static inline void count_compact_event(enum vm_event_item item) { count_vm_event(item); @@ -51,11 +56,6 @@ static inline void count_compact_events( #define pageblock_end_pfn(pfn) block_end_pfn(pfn, pageblock_order) /* - * Fragmentation score check interval for proactive compaction purposes. - */ -static const unsigned int HPAGE_FRAG_CHECK_INTERVAL_MSEC = 500; - -/* * Page order with-respect-to which proactive compaction * calculates external fragmentation, which is used as * the "fragmentation score" of a node/zone. _