linux/arch
Wanpeng Li 010fd37fdd KVM: LAPIC: Reduce world switch latency caused by timer_advance_ns
All the checks in lapic_timer_int_injected(), __kvm_wait_lapic_expire(), and
these function calls waste cpu cycles when the timer mode is not tscdeadline.
We can observe ~1.3% world switch time overhead by kvm-unit-tests/vmexit.flat
vmcall testing on AMD server. This patch reduces the world switch latency
caused by timer_advance_ns feature when the timer mode is not tscdeadline by
simpling move the check against apic->lapic_timer.expired_tscdeadline much
earlier.

Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1599731444-3525-7-git-send-email-wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-28 07:57:10 -04:00
..
alpha treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
arc ARC fixes for 5.9-rc4 2020-09-05 13:46:14 -07:00
arm A set of fixes for lockdep, tracing and RCU: 2020-08-30 11:43:50 -07:00
arm64 Merge branch 'x86-seves-for-paolo' of https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into HEAD 2020-09-22 06:43:17 -04:00
c6x treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
csky treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
h8300 treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
hexagon treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
ia64 ia64: fix min_low_pfn/max_low_pfn build errors 2020-09-01 19:34:11 +03:00
m68k treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
microblaze microblaze: fix min_low_pfn/max_low_pfn build errors 2020-08-31 19:52:50 +03:00
mips Merge branch 'x86-seves-for-paolo' of https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into HEAD 2020-09-22 06:43:17 -04:00
nds32 A set of fixes for lockdep, tracing and RCU: 2020-08-30 11:43:50 -07:00
nios2 mm/nios2: use general page fault accounting 2020-08-12 10:58:03 -07:00
openrisc treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
parisc treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
powerpc PPC KVM update for 5.10 2020-09-22 08:18:16 -04:00
riscv treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
s390 s390: update defconfigs 2020-09-02 13:17:05 +02:00
sh treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
sparc treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
um treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
x86 KVM: LAPIC: Reduce world switch latency caused by timer_advance_ns 2020-09-28 07:57:10 -04:00
xtensa treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
.gitignore
Kconfig A set oftimekeeping/VDSO updates: 2020-08-14 14:26:08 -07:00