linux/arch
Pallipadi, Venkatesh e888d7facd x86, delay: tsc based udelay should have rdtsc_barrier
delay_tsc needs rdtsc_barrier to provide proper delay.

Output from a test driver using hpet to cross check delay
provided by udelay().

Before:
[   86.794363] Expected delay 5us actual 4679ns
[   87.154362] Expected delay 5us actual 698ns
[   87.514162] Expected delay 5us actual 4539ns
[   88.653716] Expected delay 5us actual 4539ns
[   94.664106] Expected delay 10us actual 9638ns
[   95.049351] Expected delay 10us actual 10126ns
[   95.416110] Expected delay 10us actual 9568ns
[   95.799216] Expected delay 10us actual 9638ns
[  103.624104] Expected delay 10us actual 9707ns
[  104.020619] Expected delay 10us actual 768ns
[  104.419951] Expected delay 10us actual 9707ns

After:
[   50.983320] Expected delay 5us actual 5587ns
[   51.261807] Expected delay 5us actual 5587ns
[   51.565715] Expected delay 5us actual 5657ns
[   51.861171] Expected delay 5us actual 5587ns
[   52.164704] Expected delay 5us actual 5726ns
[   52.487457] Expected delay 5us actual 5657ns
[   52.789338] Expected delay 5us actual 5726ns
[   57.119680] Expected delay 10us actual 10755ns
[   57.893997] Expected delay 10us actual 10615ns
[   58.261287] Expected delay 10us actual 10755ns
[   58.620505] Expected delay 10us actual 10825ns
[   58.941035] Expected delay 10us actual 10755ns
[   59.320903] Expected delay 10us actual 10615ns
[   61.306311] Expected delay 10us actual 10755ns
[   61.520542] Expected delay 10us actual 10615ns

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-06-25 16:47:40 -07:00
..
alpha Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
arm Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
avr32 Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
blackfin Blackfin: convert page/tlb to asm-generic 2009-06-18 21:42:30 -04:00
cris Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
frv Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
h8300 ptrace: remove PT_DTRACE from arch/h8300 2009-06-18 13:03:48 -07:00
ia64 Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
m32r Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
m68k Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
m68knommu ptrace: remove PT_DTRACE from m68k, m68knommu 2009-06-18 13:03:48 -07:00
microblaze Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
mips Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
mn10300 Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
parisc Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
powerpc Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
s390 Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
sh Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
sparc Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
um Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
x86 x86, delay: tsc based udelay should have rdtsc_barrier 2009-06-25 16:47:40 -07:00
xtensa Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
.gitignore
Kconfig gcov: add gcov profiling infrastructure 2009-06-18 13:03:57 -07:00