Sebastian Andrzej Siewior 577ff465f5 x86/fpu: Only write PKRU if it is different from current ... According to Dave Hansen, WRPKRU is more expensive than RDPKRU. It has a higher cycle cost and it's also practically a (light) speculation barrier. As an optimisation read the current PKRU value and only write the new one if it is different. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Dave Hansen <dave.hansen@intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: "Jason A. Donenfeld" <Jason@zx2c4.com> Cc: Juergen Gross <jgross@suse.com> Cc: kvm ML <kvm@vger.kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Rik van Riel <riel@surriel.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20190403164156.19645-14-bigeasy@linutronix.de		2019-04-11 15:41:05 +02:00
..
boot	x86/boot: Fix incorrect ifdeffery scope	2019-03-27 14:00:51 +01:00
configs
crypto
entry	pidfd patches for v5.1-rc1	2019-03-16 13:47:14 -07:00
events	perf/x86/intel: Make dev_attr_allow_tsx_force_abort static	2019-03-17 08:40:18 +01:00
hyperv	x86/hyperv: Prevent potential NULL pointer dereference	2019-03-21 12:24:39 +01:00
ia32	x86/fpu: Remove fpu->initialized	2019-04-10 15:42:40 +02:00
include	x86/fpu: Only write PKRU if it is different from current	2019-04-11 15:41:05 +02:00
kernel	x86/fpu: Use a feature number instead of mask in two more helpers	2019-04-10 18:20:27 +02:00
kvm	x86/pkeys: Provide *pkru() helpers	2019-04-11 15:40:58 +02:00
lib	x86/lib: Fix indentation issue, remove extra tab	2019-03-21 12:24:38 +01:00
math-emu	x86/fpu: Always init the state in fpu__clear()	2019-04-09 19:28:06 +02:00
mm	x86/fpu: Use a feature number instead of mask in two more helpers	2019-04-10 18:20:27 +02:00
net
oprofile
pci
platform	x86/realmode: Make set_real_mode_mem() static inline	2019-03-29 10:16:27 +01:00
power
purgatory
ras
realmode	x86/realmode: Make set_real_mode_mem() static inline	2019-03-29 10:16:27 +01:00
tools
um
video
xen	Merge branch 'akpm' (patches from Andrew)	2019-03-12 10:39:53 -07:00
.gitignore
Kbuild
Kconfig	x86/smp: Enforce CONFIG_HOTPLUG_CPU when SMP=y	2019-03-28 13:34:58 +01:00
Kconfig.cpu
Kconfig.debug
Makefile	x86/retpolines: Disable switch jump tables when retpolines are enabled	2019-03-28 13:39:48 +01:00
Makefile_32.cpu
Makefile.um