x86, pvticketlock: Use callee-save for lock_spinning

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Although the lock_spinning calls in the spinlock code are on the
uncommon path, their presence can cause the compiler to generate many
more register save/restores in the function pre/postamble, which is in
the fast path.  To avoid this, convert it to using the pvops callee-save
calling convention, which defers all the save/restores until the actual
function is called, keeping the fastpath clean.

Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Link: http://lkml.kernel.org/r/1376058122-8248-8-git-send-email-raghavendra.kt@linux.vnet.ibm.com
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Attilio Rao <attilio.rao@citrix.com>
Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

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Jeremy Fitzhardinge 2013-08-09 19:51:55 +05:30 • committed by H. Peter Anvin

parent b8fa70b51a

commit 354714dd26

4 changed files with 5 additions and 4 deletions

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arch/x86/include/asm/paravirt.h

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arch/x86/include/asm/paravirt_types.h

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arch/x86/kernel/paravirt-spinlocks.c

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arch/x86/xen/spinlock.c

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