lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

x86: udelay: Use this_cpu_read to avoid address calculation

Browse Source 
The code will use a segment prefix instead of doing the lookup and
calculation.

Signed-off-by: Christoph Lameter <cl@linux.com>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Christoph Lameter
2010-12-16 12:14:43 -06:00
committed by Tejun Heo
parent c1955b5f3a
commit 357089fca9
1 changed files with 1 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
arch/x86/lib/delay.c
View File

@@ -121,7 +121,7 @@ inline void __const_udelay(unsigned long xloops)
asm("mull %%edx" asm("mull %%edx"
:"=d" (xloops), "=&a" (d0) :"=d" (xloops), "=&a" (d0)
:"1" (xloops), "0" :"1" (xloops), "0"
(cpu_data(raw_smp_processor_id()).loops_per_jiffy * (HZ/4))); (this_cpu_read(cpu_info.loops_per_jiffy) * (HZ/4)));
__delay(++xloops); __delay(++xloops);
} }