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linux-next/arch/x86/kernel/cpu
Maciej W. Rozycki 593f4a788e x86: APIC: remove apic_write_around(); use alternatives
Use alternatives to select the workaround for the 11AP Pentium erratum
for the affected steppings on the fly rather than build time.  Remove the
X86_GOOD_APIC configuration option and replace all the calls to
apic_write_around() with plain apic_write(), protecting accesses to the
ESR as appropriate due to the 3AP Pentium erratum.  Remove
apic_read_around() and all its invocations altogether as not needed.
Remove apic_write_atomic() and all its implementing backends.  The use of
ASM_OUTPUT2() is not strictly needed for input constraints, but I have
used it for readability's sake.

I had the feeling no one else was brave enough to do it, so I went ahead
and here it is.  Verified by checking the generated assembly and tested
with both a 32-bit and a 64-bit configuration, also with the 11AP
"feature" forced on and verified with gdb on /proc/kcore to work as
expected (as an 11AP machines are quite hard to get hands on these days).
Some script complained about the use of "volatile", but apic_write() needs
it for the same reason and is effectively a replacement for writel(), so I
have disregarded it.

I am not sure what the policy wrt defconfig files is, they are generated
and there is risk of a conflict resulting from an unrelated change, so I
have left changes to them out.  The option will get removed from them at
the next run.

Some testing with machines other than mine will be needed to avoid some
stupid mistake, but despite its volume, the change is not really that
intrusive, so I am fairly confident that because it works for me, it will
everywhere.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 12:51:21 +02:00
..
cpufreq x86: coding style fixes to x86/kernel/cpu/cpufreq/cpufreq-nforce2.c 2008-06-18 15:00:14 +02:00
mcheck x86: APIC: remove apic_write_around(); use alternatives 2008-07-18 12:51:21 +02:00
mtrr Merge branch 'generic-ipi' into generic-ipi-for-linus 2008-07-15 21:55:59 +02:00
addon_cpuid_features.c x86: PAT: fixed checkpatch errors (and whitespaces) 2008-06-12 10:14:24 +02:00
amd_64.c x86: max_low_pfn_mapped fix, #2 2008-07-13 08:19:16 +02:00
amd.c x86: Move PCI IO ECS code to x86/pci 2008-07-08 07:47:39 +02:00
bugs_64.c x86: move bugs_64.c to cpu/bugs_64.c 2008-06-03 14:43:00 -07:00
bugs.c x86: APIC: remove apic_write_around(); use alternatives 2008-07-18 12:51:21 +02:00
centaur_64.c x86: get x86_phys_bits early 2008-07-14 09:24:16 +02:00
centaur.c x86: clean up cpu capabilities accesses, centaur.c 2008-04-17 17:40:51 +02:00
common_64.c x86: get x86_phys_bits early 2008-07-14 09:24:16 +02:00
common.c x86: change identify_cpu to static 2008-07-08 12:48:35 +02:00
cpu.h x86: make 64-bit identify_cpu use cpu_dev 2008-07-08 07:47:39 +02:00
cyrix.c x86: clean up cpu capabilities accesses, cyrix.c 2008-04-17 17:40:51 +02:00
feature_names.c x86: arch/x86/kernel/cpu/feature_names.c - use angle brackets for include 2008-04-17 17:40:57 +02:00
intel_64.c x86: get x86_phys_bits early 2008-07-14 09:24:16 +02:00
intel_cacheinfo.c x86: add new cache descriptor 2008-05-12 21:28:13 +02:00
intel.c x86: APIC: remove apic_write_around(); use alternatives 2008-07-18 12:51:21 +02:00
Makefile x86: seperate funcs from setup_64 to cpu common_64.c 2008-07-08 12:48:34 +02:00
perfctr-watchdog.c Merge branch 'generic-ipi' into generic-ipi-for-linus 2008-07-15 21:55:59 +02:00
proc.c arch: Remove unnecessary inclusions of asm/semaphore.h 2008-04-18 22:14:49 -04:00
transmeta.c x86: clean up cpu capabilities accesses, transmeta.c 2008-04-17 17:40:51 +02:00
umc.c x86: coding style fixes to arch/x86/kernel/cpu/umc.c 2008-04-17 17:40:49 +02:00