Re: [PATCH 4/6] kvm: Select SCHED_INFO instead of TASK_DELAY_ACCT

From: Paolo Bonzini
Date: Wed May 05 2021 - 07:37:20 EST


On 05/05/21 12:59, Peter Zijlstra wrote:
AFAICT KVM only relies on SCHED_INFO. Nothing uses the p->delays data
that belongs to TASK_DELAY_ACCT.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>

Right, SCHED_INFO didn't exist at the time (it was introduced in 2015, while KVM started using run_delay in 2011). I'm not sure if it could have used SCHEDSTATS instead.

Acked-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>

Paolo

---
arch/arm64/kvm/Kconfig | 5 +----
arch/x86/kvm/Kconfig | 5 +----
2 files changed, 2 insertions(+), 8 deletions(-)

--- a/arch/arm64/kvm/Kconfig
+++ b/arch/arm64/kvm/Kconfig
@@ -20,8 +20,6 @@ if VIRTUALIZATION
menuconfig KVM
bool "Kernel-based Virtual Machine (KVM) support"
depends on OF
- # for TASKSTATS/TASK_DELAY_ACCT:
- depends on NET && MULTIUSER
select MMU_NOTIFIER
select PREEMPT_NOTIFIERS
select HAVE_KVM_CPU_RELAX_INTERCEPT
@@ -38,8 +36,7 @@ menuconfig KVM
select IRQ_BYPASS_MANAGER
select HAVE_KVM_IRQ_BYPASS
select HAVE_KVM_VCPU_RUN_PID_CHANGE
- select TASKSTATS
- select TASK_DELAY_ACCT
+ select SCHED_INFO
help
Support hosting virtualized guest machines.
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -22,8 +22,6 @@ config KVM
tristate "Kernel-based Virtual Machine (KVM) support"
depends on HAVE_KVM
depends on HIGH_RES_TIMERS
- # for TASKSTATS/TASK_DELAY_ACCT:
- depends on NET && MULTIUSER
depends on X86_LOCAL_APIC
select PREEMPT_NOTIFIERS
select MMU_NOTIFIER
@@ -36,8 +34,7 @@ config KVM
select KVM_ASYNC_PF
select USER_RETURN_NOTIFIER
select KVM_MMIO
- select TASKSTATS
- select TASK_DELAY_ACCT
+ select SCHED_INFO
select PERF_EVENTS
select HAVE_KVM_MSI
select HAVE_KVM_CPU_RELAX_INTERCEPT