From 9a3c05e658d4d31b38ef03fe5c17bc2039402ff7 Mon Sep 17 00:00:00 2001 From: Zhenzhong Duan Date: Wed, 23 Oct 2019 19:16:23 +0800 Subject: [PATCH] xen: Mark "xen_nopvspin" parameter obsolete Map "xen_nopvspin" to "nopvspin", fix stale description of "xen_nopvspin" as we use qspinlock now. Signed-off-by: Zhenzhong Duan Reviewed-by: Boris Ostrovsky Cc: Jonathan Corbet Cc: Boris Ostrovsky Cc: Juergen Gross Cc: Stefano Stabellini Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: "H. Peter Anvin" Signed-off-by: Paolo Bonzini --- Documentation/admin-guide/kernel-parameters.txt | 7 ++++--- arch/x86/xen/spinlock.c | 4 ++-- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 6a8934f..4740d0d 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -5712,8 +5712,9 @@ panic() code such as dumping handler. xen_nopvspin [X86,XEN] - Disables the ticketlock slowpath using Xen PV - optimizations. + Disables the qspinlock slowpath using Xen PV optimizations. + This parameter is obsoleted by "nopvspin" parameter, which + has equivalent effect for XEN platform. xen_nopv [X86] Disables the PV optimizations forcing the HVM guest to @@ -5739,7 +5740,7 @@ as generic guest with no PV drivers. Currently support XEN HVM, KVM, HYPER_V and VMWARE guest. - nopvspin [X86,KVM] + nopvspin [X86,XEN,KVM] Disables the qspinlock slow path using PV optimizations which allow the hypervisor to 'idle' the guest on lock contention. diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c index 6deb490..799f4eb 100644 --- a/arch/x86/xen/spinlock.c +++ b/arch/x86/xen/spinlock.c @@ -114,9 +114,8 @@ PV_CALLEE_SAVE_REGS_THUNK(xen_vcpu_stolen); */ void __init xen_init_spinlocks(void) { - /* Don't need to use pvqspinlock code if there is only 1 vCPU. */ - if (num_possible_cpus() == 1) + if (num_possible_cpus() == 1 || nopvspin) xen_pvspin = false; if (!xen_pvspin) { @@ -137,6 +136,7 @@ void __init xen_init_spinlocks(void) static __init int xen_parse_nopvspin(char *arg) { + pr_notice("\"xen_nopvspin\" is deprecated, please use \"nopvspin\" instead\n"); xen_pvspin = false; return 0; } -- 2.7.4