linux/arch/x86
Peter Zijlstra (Intel) f233f7f158 locking/pvqspinlock, x86: Implement the paravirt qspinlock call patching
We use the regular paravirt call patching to switch between:

  native_queued_spin_lock_slowpath()	__pv_queued_spin_lock_slowpath()
  native_queued_spin_unlock()		__pv_queued_spin_unlock()

We use a callee saved call for the unlock function which reduces the
i-cache footprint and allows 'inlining' of SPIN_UNLOCK functions
again.

We further optimize the unlock path by patching the direct call with a
"movb $0,%arg1" if we are indeed using the native unlock code. This
makes the unlock code almost as fast as the !PARAVIRT case.

This significantly lowers the overhead of having
CONFIG_PARAVIRT_SPINLOCKS enabled, even for native code.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel J Blueman <daniel@numascale.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <paolo.bonzini@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1429901803-29771-10-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:37:09 +02:00
..
boot * Avoid garbage names in efivarfs due to buggy firmware by zero'ing 2015-05-06 08:30:24 +02:00
configs x86/build/defconfig: Enable USB_EHCI_TT_NEWSCHED=y 2015-02-19 02:21:14 +01:00
crypto crypto: x86/sha512_ssse3 - fixup for asm function prototype change 2015-04-24 20:09:01 +08:00
ia32 x86_64, asm: Work around AMD SYSRET SS descriptor attribute issue 2015-04-26 17:57:38 -07:00
include locking/pvqspinlock, x86: Implement the paravirt qspinlock call patching 2015-05-08 12:37:09 +02:00
kernel locking/pvqspinlock, x86: Implement the paravirt qspinlock call patching 2015-05-08 12:37:09 +02:00
kvm kvm: x86: fix kvmclock update protocol 2015-04-27 15:48:59 +02:00
lguest Some virtio internal cleanups, a new virtio device "virtio input", and 2015-04-22 10:55:06 -07:00
lib x86: fix special __probe_kernel_write() tail zeroing case 2015-04-24 06:58:27 -07:00
math-emu
mm Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-05-06 10:57:37 -07:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-12-10 15:48:20 -05:00
oprofile x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()' 2015-03-23 11:14:17 +01:00
pci x86/PCI/ACPI: Make all resources except [io 0xcf8-0xcff] available on PCI bus 2015-04-30 22:17:34 +02:00
platform TTY/Serial patches for 4.1-rc1 2015-04-21 09:33:10 -07:00
power x86/asm/entry: Rename 'init_tss' to 'cpu_tss' 2015-03-06 08:32:58 +01:00
purgatory Merge branches 'x86-build-for-linus', 'x86-cleanups-for-linus' and 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-12-10 12:35:46 -08:00
realmode Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-02-16 14:58:12 -08:00
syscalls xen: features and fixes for 4.1-rc0 2015-04-16 14:01:03 -05:00
tools x86, build: replace Perl script with Shell script 2015-01-26 13:37:18 -08:00
um Merge branch 'exec_domain_rip_v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc 2015-04-15 13:53:55 -07:00
vdso x86: pvclock: Really remove the sched notifier for cross-cpu migrations 2015-04-27 15:49:30 +02:00
video
xen hypervisor/x86/xen: Unset X86_BUG_SYSRET_SS_ATTRS on Xen PV guests 2015-05-05 18:27:43 +01:00
.gitignore x86/build: Add arch/x86/purgatory/ make generated files to gitignore 2014-10-09 09:29:46 +02:00
Kbuild
Kconfig locking/pvqspinlock, x86: Implement the paravirt qspinlock call patching 2015-05-08 12:37:09 +02:00
Kconfig.cpu
Kconfig.debug x86, intel-mid: remove Intel MID specific serial support 2015-03-07 03:25:18 +01:00
Makefile kbuild: use relative path more to include Makefile 2015-04-02 16:42:08 +02:00
Makefile.um kbuild: use relative path more to include Makefile 2015-04-02 16:42:08 +02:00
Makefile_32.cpu