Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer updates from Thomas Gleixner:
 "Nothing exciting, just the usual pile of fixes, updates and cleanups:

   - A bunch of clocksource driver updates

   - Removal of CONFIG_TIMER_STATS and the related /proc file

   - More posix timer slim down work

   - A scalability enhancement in the tick broadcast code

   - Math cleanups"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  hrtimer: Catch invalid clockids again
  math64, tile: Fix build failure
  clocksource/drivers/arm_arch_timer:: Mark cyclecounter __ro_after_init
  timerfd: Protect the might cancel mechanism proper
  timer_list: Remove useless cast when printing
  time: Remove CONFIG_TIMER_STATS
  clocksource/drivers/arm_arch_timer: Work around Hisilicon erratum 161010101
  clocksource/drivers/arm_arch_timer: Introduce generic errata handling infrastructure
  clocksource/drivers/arm_arch_timer: Remove fsl-a008585 parameter
  clocksource/drivers/arm_arch_timer: Add dt binding for hisilicon-161010101 erratum
  clocksource/drivers/ostm: Add renesas-ostm timer driver
  clocksource/drivers/ostm: Document renesas-ostm timer DT bindings
  clocksource/drivers/tcb_clksrc: Use 32 bit tcb as sched_clock
  clocksource/drivers/gemini: Add driver for the Cortina Gemini
  clocksource: add DT bindings for Cortina Gemini
  clockevents: Add a clkevt-of mechanism like clksrc-of
  tick/broadcast: Reduce lock cacheline contention
  timers: Omit POSIX timer stuff from task_struct when disabled
  x86/timer: Make delay() work during early bootup
  delay: Add explanation of udelay() inaccuracy
  ...

2 files changed, 13 insertions, 2 deletions

diff --git a/arch/x86/include/asm/div64.h b/arch/x86/include/asm/div64.h
index ced283ac79df..af95c47d5c9e 100644
--- a/arch/x86/include/asm/div64.h
+++ b/arch/x86/include/asm/div64.h
@@ -59,6 +59,17 @@ static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder)
 }
 #define div_u64_rem	div_u64_rem
 
+static inline u64 mul_u32_u32(u32 a, u32 b)
+{
+	u32 high, low;
+
+	asm ("mull %[b]" : "=a" (low), "=d" (high)
+			 : [a] "a" (a), [b] "rm" (b) );
+
+	return low | ((u64)high) << 32;
+}
+#define mul_u32_u32 mul_u32_u32
+
 #else
 # include <asm-generic/div64.h>
 #endif /* CONFIG_X86_32 */
diff --git a/arch/x86/lib/delay.c b/arch/x86/lib/delay.c
index 073d1f1a620b..a8e91ae89fb3 100644
--- a/arch/x86/lib/delay.c
+++ b/arch/x86/lib/delay.c
@@ -156,13 +156,13 @@ EXPORT_SYMBOL(__delay);
 
 inline void __const_udelay(unsigned long xloops)
 {
+	unsigned long lpj = this_cpu_read(cpu_info.loops_per_jiffy) ? : loops_per_jiffy;
 	int d0;
 
 	xloops *= 4;
 	asm("mull %%edx"
 		:"=d" (xloops), "=&a" (d0)
-		:"1" (xloops), "0"
-		(this_cpu_read(cpu_info.loops_per_jiffy) * (HZ/4)));
+		:"1" (xloops), "0" (lpj * (HZ / 4)));
 
 	__delay(++xloops);
 }