lkml.org 
[lkml]   [2019]   [Feb]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.9 43/63] clocksource: Use GENMASK_ULL in definition of CLOCKSOURCE_MASK
Date
4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Matthias Kaehlcke <mka@chromium.org>

commit 0773cea37470f8e080c510fe720fc356cf35df3a upstream

Besides reusing existing code this removes the special case handling
for 64-bit masks, which causes clang to raise a shift count overflow
warning due to https://bugs.llvm.org//show_bug.cgi?id=10030.

Suggested-by: Dmitry Torokhov <dtor@chromium.org>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Cc: Grant Grundler <grundler@chromium.org>
Cc: Greg Hackmann <ghackmann@google.com>
Cc: Michael Davidson <md@google.com>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20170418233037.70990-1-mka@chromium.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[nc: cycle_t wasn't eliminated until commit a5a1d1c2914b ("clocksource:
Use a plain u64 instead of cycle_t") in v4.10]
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
include/linux/clocksource.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -117,7 +117,7 @@ struct clocksource {
#define CLOCK_SOURCE_RESELECT 0x100

/* simplify initialization of mask field */
-#define CLOCKSOURCE_MASK(bits) (cycle_t)((bits) < 64 ? ((1ULL<<(bits))-1) : -1)
+#define CLOCKSOURCE_MASK(bits) GENMASK_ULL((bits) - 1, 0)

static inline u32 clocksource_freq2mult(u32 freq, u32 shift_constant, u64 from)
{

\
 
 \ /
  Last update: 2019-02-25 22:15    [W:0.165 / U:2.120 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site