Wanpeng Li
0c5f81dad4
KVM: LAPIC: Inject timer interrupt via posted interrupt
...
Dedicated instances are currently disturbed by unnecessary jitter due
to the emulated lapic timers firing on the same pCPUs where the
vCPUs reside. There is no hardware virtual timer on Intel for guest
like ARM, so both programming timer in guest and the emulated timer fires
incur vmexits. This patch tries to avoid vmexit when the emulated timer
fires, at least in dedicated instance scenario when nohz_full is enabled.
In that case, the emulated timers can be offload to the nearest busy
housekeeping cpus since APICv has been found for several years in server
processors. The guest timer interrupt can then be injected via posted interrupts,
which are delivered by the housekeeping cpu once the emulated timer fires.
The host should tuned so that vCPUs are placed on isolated physical
processors, and with several pCPUs surplus for busy housekeeping.
If disabled mwait/hlt/pause vmexits keep the vCPUs in non-root mode,
~3% redis performance benefit can be observed on Skylake server, and the
number of external interrupt vmexits drops substantially. Without patch
VM-EXIT Samples Samples% Time% Min Time Max Time Avg time
EXTERNAL_INTERRUPT 42916 49.43% 39.30% 0.47us 106.09us 0.71us ( +- 1.09% )
While with patch:
VM-EXIT Samples Samples% Time% Min Time Max Time Avg time
EXTERNAL_INTERRUPT 6871 9.29% 2.96% 0.44us 57.88us 0.72us ( +- 4.02% )
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-07-20 09:00:40 +02:00
..
bpf
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
2019-07-11 10:55:49 -07:00
cgroup
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
2019-07-11 10:55:49 -07:00
configs
debug
treewide: Add SPDX license identifier - Makefile/Kconfig
2019-05-21 10:50:46 +02:00
dma
dma-mapping updates for Linux 5.3
2019-07-12 15:13:55 -07:00
events
Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2019-07-09 11:15:52 -07:00
gcov
gcov: no need to check return value of debugfs_create functions
2019-06-03 16:18:12 +02:00
irq
Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2019-07-08 11:22:57 -07:00
livepatch
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching
2019-07-11 15:30:05 -07:00
locking
Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2019-07-08 16:12:03 -07:00
power
Power management updates for 5.3-rc1
2019-07-09 10:05:22 -07:00
printk
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 13
2019-05-21 11:28:45 +02:00
rcu
Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
2019-06-28 19:46:47 +02:00
sched
KVM: LAPIC: Inject timer interrupt via posted interrupt
2019-07-20 09:00:40 +02:00
time
timekeeping/vsyscall: Use __iter_div_u64_rem()
2019-07-10 20:37:49 +02:00
trace
Driver Core and debugfs changes for 5.3-rc1
2019-07-12 12:24:03 -07:00
.gitignore
Provide in-kernel headers to make extending kernel easier
2019-04-29 16:48:03 +02:00
acct.c
acct_on(): don't mess with freeze protection
2019-04-04 21:04:13 -04:00
async.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
audit.c
audit/stable-5.3 PR 20190702
2019-07-08 18:55:42 -07:00
audit.h
audit/stable-5.3 PR 20190702
2019-07-08 18:55:42 -07:00
audit_fsnotify.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
2019-05-30 11:26:37 -07:00
audit_tree.c
fsnotify: switch send_to_group() and ->handle_event to const struct qstr *
2019-04-26 13:51:03 -04:00
audit_watch.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
2019-05-30 11:26:35 -07:00
auditfilter.c
audit/stable-5.3 PR 20190702
2019-07-08 18:55:42 -07:00
auditsc.c
audit: enforce op for string fields
2019-05-28 17:46:43 -04:00
backtracetest.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
bounds.c
capability.c
compat.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
2019-06-19 17:09:55 +02:00
configs.c
kernel/configs: use .incbin directive to embed config_data.gz
2019-03-07 18:32:02 -08:00
context_tracking.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
cpu.c
Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2019-07-08 10:39:56 -07:00
cpu_pm.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282
2019-06-05 17:36:37 +02:00
crash_core.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230
2019-06-19 17:09:06 +02:00
crash_dump.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
cred.c
request_key improvements
2019-07-08 19:19:37 -07:00
delayacct.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 25
2019-05-21 11:52:39 +02:00
dma.c
elfcore.c
exec_domain.c
exit.c
cgroup: Call cgroup_release() before __exit_signal()
2019-05-31 10:38:57 -07:00
extable.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
2019-05-30 11:26:35 -07:00
fail_function.c
fail_function: no need to check return value of debugfs_create functions
2019-06-03 15:49:06 +02:00
fork.c
clone3-v5.3
2019-07-11 10:09:44 -07:00
freezer.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
futex.c
Linux 5.2-rc3
2019-06-03 11:50:18 +02:00
gen_kheaders.sh
kheaders: include only headers into kheaders_data.tar.xz
2019-07-09 10:10:52 +09:00
groups.c
hung_task.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
iomem.c
mm/nvdimm: add is_ioremap_addr and use that to check ioremap address
2019-07-12 11:05:40 -07:00
irq_work.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
jump_label.c
jump_label: Batch updates if arch supports it
2019-06-17 12:09:22 +02:00
kallsyms.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
kcmp.c
Kconfig.freezer
treewide: Add SPDX license identifier - Makefile/Kconfig
2019-05-21 10:50:46 +02:00
Kconfig.hz
treewide: Add SPDX license identifier - Makefile/Kconfig
2019-05-21 10:50:46 +02:00
Kconfig.locks
treewide: Add SPDX license identifier - Makefile/Kconfig
2019-05-21 10:50:46 +02:00
Kconfig.preempt
treewide: Add SPDX license identifier - Makefile/Kconfig
2019-05-21 10:50:46 +02:00
kcov.c
kcov: convert kcov.refcount to refcount_t
2019-03-07 18:32:02 -08:00
kexec.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230
2019-06-19 17:09:06 +02:00
kexec_core.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230
2019-06-19 17:09:06 +02:00
kexec_file.c
Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
2019-07-08 20:28:59 -07:00
kexec_internal.h
kheaders.c
kheaders: Move from proc to sysfs
2019-05-24 20:16:01 +02:00
kmod.c
kprobes.c
kprobes: no need to check return value of debugfs_create functions
2019-06-03 15:49:07 +02:00
ksysfs.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 170
2019-05-30 11:26:39 -07:00
kthread.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
latencytop.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
Makefile
kheaders: Move from proc to sysfs
2019-05-24 20:16:01 +02:00
memremap.c
mm/devm_memremap_pages: fix final page put race
2019-06-13 17:34:56 -10:00
module-internal.h
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36
2019-05-24 17:27:11 +02:00
module.c
Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
2019-06-28 19:46:47 +02:00
module_signing.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36
2019-05-24 17:27:11 +02:00
notifier.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
nsproxy.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
padata.c
padata: Replace padata_attr_type default_attrs field with groups
2019-04-25 22:06:11 +02:00
panic.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
params.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
2019-05-30 11:26:35 -07:00
pid.c
pidfd-updates-v5.3
2019-07-10 22:17:21 -07:00
pid_namespace.c
Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
2019-07-08 21:48:15 -07:00
profile.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
ptrace.c
arm64 updates for 5.3:
2019-07-08 09:54:55 -07:00
range.c
reboot.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
relay.c
Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2019-03-12 13:27:20 -07:00
resource.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
rseq.c
signal: Remove task parameter from force_sig
2019-05-27 09:36:28 -05:00
seccomp.c
signal: Remove the signal number and task parameters from force_sig_info
2019-05-29 09:31:44 -05:00
signal.c
pidfd-updates-v5.3
2019-07-10 22:17:21 -07:00
smp.c
smp: Remove smp_call_function() and on_each_cpu() return values
2019-06-23 14:26:26 +02:00
smpboot.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
smpboot.h
softirq.c
Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2019-07-08 11:01:13 -07:00
stackleak.c
stacktrace.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching
2019-07-11 15:30:05 -07:00
stop_machine.c
processor: get rid of cpu_relax_yield
2019-06-15 12:25:55 +02:00
sys.c
prctl_set_mm: downgrade mmap_sem to read lock
2019-06-01 15:51:31 -07:00
sys_ni.c
arch: handle arches who do not yet define clone3
2019-06-21 01:54:53 +02:00
sysctl.c
sched/uclamp: Add system default clamps
2019-06-24 19:23:45 +02:00
sysctl_binary.c
task_work.c
taskstats.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
2019-05-30 11:26:37 -07:00
test_kprobes.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 25
2019-05-21 11:52:39 +02:00
torture.c
torture: Allow inter-stutter interval to be specified
2019-05-28 09:06:09 -07:00
tracepoint.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
2019-05-30 11:26:35 -07:00
tsacct.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
2019-05-30 11:26:37 -07:00
ucount.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
uid16.c
uid16.h
umh.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
up.c
smp: Remove smp_call_function() and on_each_cpu() return values
2019-06-23 14:26:26 +02:00
user-return-notifier.c
treewide: Add SPDX license identifier for missed files
2019-05-21 10:50:45 +02:00
user.c
Keyrings namespacing
2019-07-08 19:36:47 -07:00
user_namespace.c
Keyrings namespacing
2019-07-08 19:36:47 -07:00
utsname.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
utsname_sysctl.c
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
watchdog.c
watchdog: Fix typo in comment
2019-04-18 14:05:51 +02:00
watchdog_hld.c
kernel/watchdog_hld.c: hard lockup message should end with a newline
2019-04-19 09:46:05 -07:00
workqueue.c
workqueue: Remove GPF argument from alloc_workqueue_attrs()
2019-06-27 14:12:19 -07:00
workqueue_internal.h
sched/core, workqueues: Distangle worker accounting from rq lock
2019-04-16 16:55:15 +02:00