When the CPU is offline, the timer of LoongArch is not correctly closed.
This is harmless for real machines, but resulting in an excessively high
cpu usage rate of the offline vCPU thread in the virtual machines.
To correctly close the timer, we have made the following modifications:
Register the cpu hotplug event (CPUHP_AP_LOONGARCH_ARCH_TIMER_STARTING)
for LoongArch. This event's hooks will be called to close the timer when
the CPU is offline.
Clear the timer interrupt when the timer is turned off. Since before the
timer is turned off, there may be a timer interrupt that has already been
in the pending state due to the interruption of the disabled, which also
affects the halt state of the offline vCPU.
Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: maoxiaochuan <maoxiaochuan@loongson.cn>
When the KCOV is enabled all functions get instrumented, unless
the __no_sanitize_coverage attribute is used. To prepare for
__no_sanitize_coverage being applied to __init functions, we have to
handle differences in how GCC's inline optimizations get resolved.
For LoongArch this exposed several places where __init annotations
were missing but ended up being "accidentally correct". So fix these
cases.
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: maoxiaochuan <maoxiaochuan@loongson.cn>
Save and restore CSR.CNTC for hibernation which is similar to suspend.
For host this is unnecessary because sched clock is ensured continuous,
but for kvm guest sched clock isn't enough because rdtime.d should also
be continuous.
Host::rdtime.d = Host::CSR.CNTC + counter
Guest::rdtime.d = Host::CSR.CNTC + Host::CSR.GCNTC + Guest::CSR.CNTC + counter
so,
Guest::rdtime.d = Host::rdtime.d + Host::CSR.GCNTC + Guest::CSR.CNTC
To ensure Guest::rdtime.d continuous, Host::rdtime.d should be at first
continuous, while Host::CSR.GCNTC / Guest::CSR.CNTC is maintained by KVM.
Cc: stable@vger.kernel.org
Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: maoxiaochuan <maoxiaochuan@loongson.cn>
As per arch spec, maximum timer bits is configurable and should not be
hardcoded in any way.
Probe timer bits from PRCFG1 and use that to determine the clockevent's
max_delta to be conformance.
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: maoxiaochuan <maoxiaochuan@loongson.cn>
Now the min_delta is 0x600 (1536) for LoongArch's constant clockevent
device. For a 100MHz hardware timer this means ~15us. This is a little
big, especially for PREEMPT_RT enabled kernels. So reduce it to 100 for
PREEMPT_RT kernel, and 1000 for others (we don't want too small values
to affect performance).
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: michael <michael5hzg@gmail.com>
Signed-off-by: maoxiaochuan <maoxiaochuan@loongson.cn>
Bibo Mao