From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754122AbdKFQJe (ORCPT ); Mon, 6 Nov 2017 11:09:34 -0500 Received: from mail-wm0-f68.google.com ([74.125.82.68]:54429 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753299AbdKFQJc (ORCPT ); Mon, 6 Nov 2017 11:09:32 -0500 X-Google-Smtp-Source: ABhQp+R34VhP+A/7HY+xlN4K+gQKoscy/51krGbW6jLitm676g+PcxE246OzqqsOuT7JIGWmX1G+1Q== Subject: Re: [PATCH v7 2/5] x86/pvclock: add setter for pvclock_pvti_cpu0_va To: Joao Martins , linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, Radim Krcmar , xen-devel , Boris Ostrovsky , Juergen Gross , Andy Lutomirski References: <20171019133918.18367-1-joao.m.martins@oracle.com> <20171019133918.18367-3-joao.m.martins@oracle.com> From: Paolo Bonzini Message-ID: <591d9a46-f96e-b3a6-d412-0267f4e412e5@redhat.com> Date: Mon, 6 Nov 2017 17:09:25 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.4.0 MIME-Version: 1.0 In-Reply-To: <20171019133918.18367-3-joao.m.martins@oracle.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 19/10/2017 15:39, Joao Martins wrote: > Right now there is only a pvclock_pvti_cpu0_va() which is defined > on kvmclock since: > > commit dac16fba6fc5 > ("x86/vdso: Get pvclock data from the vvar VMA instead of the fixmap") > > The only user of this interface so far is kvm. This commit adds a > setter function for the pvti page and moves pvclock_pvti_cpu0_va > to pvclock, which is a more generic place to have it; and would > allow other PV clocksources to use it, such as Xen. > > Signed-off-by: Joao Martins > Acked-by: Andy Lutomirski Acked-by: Paolo Bonzini IOW, the Xen folks are free to pick up the whole series. :) Paolo > --- > Changes since v1: > * Rebased: the only conflict was that I had move the export > pvclock_pvti_cpu0_va() symbol as it is used by kvm PTP driver. > * Do not initialize pvti_cpu0_va to NULL (checkpatch error) > ( Comments from Andy Lutomirski ) > * Removed asm/pvclock.h 'pvclock_set_pvti_cpu0_va' definition > for non !PARAVIRT_CLOCK to better track screwed Kconfig stuff. > * Add his Acked-by (provided the previous adjustment was made) > > Changes since RFC: > (Comments from Andy Lutomirski) > * Add __init to pvclock_set_pvti_cpu0_va > * Add WARN_ON(vclock_was_used(VCLOCK_PVCLOCK)) to > pvclock_set_pvti_cpu0_va > --- > arch/x86/include/asm/pvclock.h | 19 ++++++++++--------- > arch/x86/kernel/kvmclock.c | 7 +------ > arch/x86/kernel/pvclock.c | 14 ++++++++++++++ > 3 files changed, 25 insertions(+), 15 deletions(-) > > diff --git a/arch/x86/include/asm/pvclock.h b/arch/x86/include/asm/pvclock.h > index 448cfe1b48cf..6f228f90cdd7 100644 > --- a/arch/x86/include/asm/pvclock.h > +++ b/arch/x86/include/asm/pvclock.h > @@ -4,15 +4,6 @@ > #include > #include > > -#ifdef CONFIG_KVM_GUEST > -extern struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void); > -#else > -static inline struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void) > -{ > - return NULL; > -} > -#endif > - > /* some helper functions for xen and kvm pv clock sources */ > u64 pvclock_clocksource_read(struct pvclock_vcpu_time_info *src); > u8 pvclock_read_flags(struct pvclock_vcpu_time_info *src); > @@ -101,4 +92,14 @@ struct pvclock_vsyscall_time_info { > > #define PVTI_SIZE sizeof(struct pvclock_vsyscall_time_info) > > +#ifdef CONFIG_PARAVIRT_CLOCK > +void pvclock_set_pvti_cpu0_va(struct pvclock_vsyscall_time_info *pvti); > +struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void); > +#else > +static inline struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void) > +{ > + return NULL; > +} > +#endif > + > #endif /* _ASM_X86_PVCLOCK_H */ > diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c > index d88967659098..538738047ff5 100644 > --- a/arch/x86/kernel/kvmclock.c > +++ b/arch/x86/kernel/kvmclock.c > @@ -47,12 +47,6 @@ early_param("no-kvmclock", parse_no_kvmclock); > static struct pvclock_vsyscall_time_info *hv_clock; > static struct pvclock_wall_clock wall_clock; > > -struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void) > -{ > - return hv_clock; > -} > -EXPORT_SYMBOL_GPL(pvclock_pvti_cpu0_va); > - > /* > * The wallclock is the time of day when we booted. Since then, some time may > * have elapsed since the hypervisor wrote the data. So we try to account for > @@ -334,6 +328,7 @@ int __init kvm_setup_vsyscall_timeinfo(void) > return 1; > } > > + pvclock_set_pvti_cpu0_va(hv_clock); > put_cpu(); > > kvm_clock.archdata.vclock_mode = VCLOCK_PVCLOCK; > diff --git a/arch/x86/kernel/pvclock.c b/arch/x86/kernel/pvclock.c > index 5c3f6d6a5078..cb7d6d9c9c2d 100644 > --- a/arch/x86/kernel/pvclock.c > +++ b/arch/x86/kernel/pvclock.c > @@ -25,8 +25,10 @@ > > #include > #include > +#include > > static u8 valid_flags __read_mostly = 0; > +static struct pvclock_vsyscall_time_info *pvti_cpu0_va __read_mostly; > > void pvclock_set_flags(u8 flags) > { > @@ -144,3 +146,15 @@ void pvclock_read_wallclock(struct pvclock_wall_clock *wall_clock, > > set_normalized_timespec(ts, now.tv_sec, now.tv_nsec); > } > + > +void pvclock_set_pvti_cpu0_va(struct pvclock_vsyscall_time_info *pvti) > +{ > + WARN_ON(vclock_was_used(VCLOCK_PVCLOCK)); > + pvti_cpu0_va = pvti; > +} > + > +struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void) > +{ > + return pvti_cpu0_va; > +} > +EXPORT_SYMBOL_GPL(pvclock_pvti_cpu0_va); >