From b27211db61aed86f095e76aa61eaef3bf3e0b7c2 Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Tue, 18 Jul 2023 14:44:19 -0700 Subject: drm/v3d: Avoid -Wconstant-logical-operand in nsecs_to_jiffies_timeout() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit A proposed update to clang's -Wconstant-logical-operand to warn when the left hand side is a constant shows the following instance in nsecs_to_jiffies_timeout() when NSEC_PER_SEC is not a multiple of HZ, such as CONFIG_HZ=300: In file included from drivers/gpu/drm/v3d/v3d_debugfs.c:12: drivers/gpu/drm/v3d/v3d_drv.h:343:24: warning: use of logical '&&' with constant operand [-Wconstant-logical-operand] 343 | if (NSEC_PER_SEC % HZ && | ~~~~~~~~~~~~~~~~~ ^ drivers/gpu/drm/v3d/v3d_drv.h:343:24: note: use '&' for a bitwise operation 343 | if (NSEC_PER_SEC % HZ && | ^~ | & drivers/gpu/drm/v3d/v3d_drv.h:343:24: note: remove constant to silence this warning 1 warning generated. Turn this into an explicit comparison against zero to make the expression a boolean to make it clear this should be a logical check, not a bitwise one. Link: https://reviews.llvm.org/D142609 Signed-off-by: Nathan Chancellor Reviewed-by: Maíra Canal Reviewed-by: Nick Desaulniers Signed-off-by: Maíra Canal Link: https://patchwork.freedesktop.org/patch/msgid/20230718-nsecs_to_jiffies_timeout-constant-logical-operand-v1-1-36ed8fc8faea@kernel.org --- drivers/gpu/drm/v3d/v3d_drv.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/gpu/drm/v3d') diff --git a/drivers/gpu/drm/v3d/v3d_drv.h b/drivers/gpu/drm/v3d/v3d_drv.h index b74b1351bfc8..7f664a4b2a75 100644 --- a/drivers/gpu/drm/v3d/v3d_drv.h +++ b/drivers/gpu/drm/v3d/v3d_drv.h @@ -340,7 +340,7 @@ struct v3d_submit_ext { static inline unsigned long nsecs_to_jiffies_timeout(const u64 n) { /* nsecs_to_jiffies64() does not guard against overflow */ - if (NSEC_PER_SEC % HZ && + if ((NSEC_PER_SEC % HZ) != 0 && div_u64(n, NSEC_PER_SEC) >= MAX_JIFFY_OFFSET / HZ) return MAX_JIFFY_OFFSET; -- cgit v1.2.3