linux-stable/arch/powerpc
Anton Blanchard eca590f402 powerpc/rtas: Only sleep in rtas_busy_delay if we have useful work to do
RTAS returns extended error codes as a hint of how long the
OS might want to wait before retrying a call. If we have nothing
else useful to do we may as well call back straight away.

This was found when testing the new dynamic dma window feature.
Firmware split the zeroing of the TCE table into 32k chunks but
returned 9901 (which is a suggested wait of 10ms). All up this took
about 10 minutes to complete since msleep is jiffies based and will
round 10ms up to 20ms.

With the patch below we take 3 seconds to complete the same test.
The hint firmware is returning in the RTAS call should definitely
be decreased, but even if we slept 1ms each iteration this would
take 32s.

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-04-27 14:18:50 +10:00
..
boot powerpc/boot: Add an ePAPR compliant boot wrapper 2011-04-20 16:59:21 +10:00
configs powerpc: Fix build warning of the defconfigs 2011-04-27 14:18:41 +10:00
include/asm powerpc/book3e: Fix extlb size 2011-04-27 14:18:48 +10:00
kernel powerpc/rtas: Only sleep in rtas_busy_delay if we have useful work to do 2011-04-27 14:18:50 +10:00
kvm powerpc: Always use SPRN_SPRG_HSCRATCH0 when running in HV mode 2011-04-20 11:03:23 +10:00
lib powerpc: Use MSR_64BIT in sstep.c, fix kprobes on BOOK3E 2011-04-27 14:18:46 +10:00
math-emu powerpc/85xx: Fix SPE float to integer conversion failure 2011-03-15 13:48:15 -05:00
mm powerpc/numa: Look for ibm, associativity-reference-points at the root 2011-04-27 14:18:35 +10:00
oprofile Fix common misspellings 2011-03-31 11:26:23 -03:00
platforms powerpc/ps3: Update debug message for irq_set_chip_data() 2011-04-27 14:18:39 +10:00
sysdev powerpc/nvram: Search for nvram using compatible 2011-04-20 17:01:20 +10:00
xmon powerpc: Use MSR_64BIT in places 2011-04-27 14:18:44 +10:00
Kconfig powerpc/boot: Add an ePAPR compliant boot wrapper 2011-04-20 16:59:21 +10:00
Kconfig.debug powerpc: Unconditionally enabled irq stacks 2010-06-15 15:02:37 +10:00
Makefile powerpc: Fix typo in uImage target 2010-08-24 15:26:32 +10:00
relocs_check.pl powerpc: Check for unsupported relocs when using CONFIG_RELOCATABLE 2009-09-24 15:31:40 +10:00