[PATCH v3 4/4] x86/hyperv: Mark "hv_nopvspin" parameter obsolete and map it to "nopvspin"
From: Zhenzhong Duan <hidden>
Date: 2019-10-01 12:40:43
Also in:
kvm, lkml
Subsystem:
documentation, the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Jonathan Corbet, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
Includes asm/hypervisor.h in order to reference x86_hyper_type. Signed-off-by: Zhenzhong Duan <redacted> Cc: Jonathan Corbet <corbet@lwn.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <redacted> Cc: Sasha Levin <sashal@kernel.org> Cc: Thomas Gleixner <redacted> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> --- Documentation/admin-guide/kernel-parameters.txt | 6 +++++- arch/x86/hyperv/hv_spinlock.c | 9 +++++---- 2 files changed, 10 insertions(+), 5 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 1f0a62f..43f922c 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt@@ -1436,6 +1436,10 @@ hv_nopvspin [X86,HYPER_V] Disables the paravirt spinlock optimizations which allow the hypervisor to 'idle' the guest on lock contention. + This parameter is obsoleted by "nopvspin" + parameter, which has equivalent effect for + HYPER_V platform. + keep_bootcon [KNL] Do not unregister boot console at start. This is only
@@ -5331,7 +5335,7 @@ as generic guest with no PV drivers. Currently support XEN HVM, KVM, HYPER_V and VMWARE guest. - nopvspin [X86,XEN,KVM] Disables the qspinlock slow path + nopvspin [X86,XEN,KVM,HYPER_V] Disables the qspinlock slow path using PV optimizations which allow the hypervisor to 'idle' the guest on lock contention.
diff --git a/arch/x86/hyperv/hv_spinlock.c b/arch/x86/hyperv/hv_spinlock.c
index 07f21a0..e00e319 100644
--- a/arch/x86/hyperv/hv_spinlock.c
+++ b/arch/x86/hyperv/hv_spinlock.c@@ -12,12 +12,11 @@ #include <linux/spinlock.h> +#include <asm/hypervisor.h> #include <asm/mshyperv.h> #include <asm/paravirt.h> #include <asm/apic.h> -static bool __initdata hv_pvspin = true; - static void hv_qlock_kick(int cpu) { apic->send_IPI(cpu, X86_PLATFORM_IPI_VECTOR);
@@ -64,7 +63,7 @@ __visible bool hv_vcpu_is_preempted(int vcpu) void __init hv_init_spinlocks(void) { - if (!hv_pvspin || !apic || + if (!pvspin || !apic || !(ms_hyperv.hints & HV_X64_CLUSTER_IPI_RECOMMENDED) || !(ms_hyperv.features & HV_X64_MSR_GUEST_IDLE_AVAILABLE)) { pr_info("PV spinlocks disabled\n");
@@ -82,7 +81,9 @@ void __init hv_init_spinlocks(void) static __init int hv_parse_nopvspin(char *arg) { - hv_pvspin = false; + pr_notice("\"hv_nopvspin\" is deprecated, please use \"nopvspin\" instead\n"); + if (x86_hyper_type == X86_HYPER_MS_HYPERV) + pvspin = false; return 0; } early_param("hv_nopvspin", hv_parse_nopvspin);
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1.8.3.1