From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 738EFC433DB for ; Wed, 10 Feb 2021 16:21:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3C05164E76 for ; Wed, 10 Feb 2021 16:21:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232263AbhBJQVN (ORCPT ); Wed, 10 Feb 2021 11:21:13 -0500 Received: from foss.arm.com ([217.140.110.172]:40226 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230005AbhBJQVK (ORCPT ); Wed, 10 Feb 2021 11:21:10 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 9DDD8113E; Wed, 10 Feb 2021 08:20:24 -0800 (PST) Received: from slackpad.fritz.box (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id ECAD83F73B; Wed, 10 Feb 2021 08:20:20 -0800 (PST) Date: Wed, 10 Feb 2021 16:19:20 +0000 From: Andre Przywara To: Marc Zyngier Cc: netdev@vger.kernel.org, yangbo.lu@nxp.com, john.stultz@linaro.org, tglx@linutronix.de, pbonzini@redhat.com, seanjc@google.com, richardcochran@gmail.com, Mark.Rutland@arm.com, will@kernel.org, suzuki.poulose@arm.com, steven.price@arm.com, lorenzo.pieralisi@arm.com, sudeep.holla@arm.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, Steve.Capper@arm.com, justin.he@arm.com, jianyong.wu@arm.com, kernel-team@android.com Subject: Re: [PATCH v18 3/7] ptp: Reorganize ptp_kvm.c to make it arch-independent Message-ID: <20210210161920.7815d1e5@slackpad.fritz.box> In-Reply-To: <20210208134029.3269384-4-maz@kernel.org> References: <20210208134029.3269384-1-maz@kernel.org> <20210208134029.3269384-4-maz@kernel.org> Organization: Arm Ltd. X-Mailer: Claws Mail 3.17.1 (GTK+ 2.24.31; x86_64-slackware-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Mon, 8 Feb 2021 13:40:25 +0000 Marc Zyngier wrote: > From: Jianyong Wu > > Currently, the ptp_kvm module contains a lot of x86-specific code. > Let's move this code into a new arch-specific file in the same directory, > and rename the arch-independent file to ptp_kvm_common.c. > > Signed-off-by: Jianyong Wu > Signed-off-by: Marc Zyngier > Link: https://lore.kernel.org/r/20201209060932.212364-4-jianyong.wu@arm.com Verified that the code movements are correct. Test compiled for x86. 1.5 nits below, but regardless: Reviewed-by: Andre Przywara > --- > drivers/ptp/Makefile | 1 + > drivers/ptp/{ptp_kvm.c => ptp_kvm_common.c} | 84 +++++------------- > drivers/ptp/ptp_kvm_x86.c | 97 +++++++++++++++++++++ > include/linux/ptp_kvm.h | 19 ++++ > 4 files changed, 139 insertions(+), 62 deletions(-) > rename drivers/ptp/{ptp_kvm.c => ptp_kvm_common.c} (60%) > create mode 100644 drivers/ptp/ptp_kvm_x86.c > create mode 100644 include/linux/ptp_kvm.h > > diff --git a/drivers/ptp/Makefile b/drivers/ptp/Makefile > index db5aef3bddc6..d11eeb5811d1 100644 > --- a/drivers/ptp/Makefile > +++ b/drivers/ptp/Makefile > @@ -4,6 +4,7 @@ > # > > ptp-y := ptp_clock.o ptp_chardev.o ptp_sysfs.o > +ptp_kvm-$(CONFIG_X86) := ptp_kvm_x86.o ptp_kvm_common.o > obj-$(CONFIG_PTP_1588_CLOCK) += ptp.o > obj-$(CONFIG_PTP_1588_CLOCK_DTE) += ptp_dte.o > obj-$(CONFIG_PTP_1588_CLOCK_INES) += ptp_ines.o > diff --git a/drivers/ptp/ptp_kvm.c b/drivers/ptp/ptp_kvm_common.c > similarity index 60% > rename from drivers/ptp/ptp_kvm.c > rename to drivers/ptp/ptp_kvm_common.c > index 658d33fc3195..721ddcede5e1 100644 > --- a/drivers/ptp/ptp_kvm.c > +++ b/drivers/ptp/ptp_kvm_common.c > @@ -8,11 +8,11 @@ > #include > #include > #include > +#include > #include > +#include > #include > #include > -#include > -#include > #include > > #include > @@ -24,56 +24,29 @@ struct kvm_ptp_clock { > > static DEFINE_SPINLOCK(kvm_ptp_lock); > > -static struct pvclock_vsyscall_time_info *hv_clock; > - > -static struct kvm_clock_pairing clock_pair; > -static phys_addr_t clock_pair_gpa; > - > static int ptp_kvm_get_time_fn(ktime_t *device_time, > struct system_counterval_t *system_counter, > void *ctx) > { > - unsigned long ret; > + long ret; > + u64 cycle; > struct timespec64 tspec; > - unsigned version; > - int cpu; > - struct pvclock_vcpu_time_info *src; > + struct clocksource *cs; > > spin_lock(&kvm_ptp_lock); > > preempt_disable_notrace(); > - cpu = smp_processor_id(); > - src = &hv_clock[cpu].pvti; > - > - do { > - /* > - * We are using a TSC value read in the hosts > - * kvm_hc_clock_pairing handling. > - * So any changes to tsc_to_system_mul > - * and tsc_shift or any other pvclock > - * data invalidate that measurement. > - */ > - version = pvclock_read_begin(src); > - > - ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, > - clock_pair_gpa, > - KVM_CLOCK_PAIRING_WALLCLOCK); > - if (ret != 0) { > - pr_err_ratelimited("clock pairing hypercall ret %lu\n", ret); > - spin_unlock(&kvm_ptp_lock); > - preempt_enable_notrace(); > - return -EOPNOTSUPP; > - } > - > - tspec.tv_sec = clock_pair.sec; > - tspec.tv_nsec = clock_pair.nsec; > - ret = __pvclock_read_cycles(src, clock_pair.tsc); > - } while (pvclock_read_retry(src, version)); > + ret = kvm_arch_ptp_get_crosststamp(&cycle, &tspec, &cs); > + if (ret) { > + spin_unlock(&kvm_ptp_lock); > + preempt_enable_notrace(); > + return ret; > + } > > preempt_enable_notrace(); > > - system_counter->cycles = ret; > - system_counter->cs = &kvm_clock; > + system_counter->cycles = cycle; > + system_counter->cs = cs; > > *device_time = timespec64_to_ktime(tspec); > > @@ -111,22 +84,17 @@ static int ptp_kvm_settime(struct ptp_clock_info *ptp, > > static int ptp_kvm_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts) > { > - unsigned long ret; > + long ret; > struct timespec64 tspec; > > spin_lock(&kvm_ptp_lock); > > - ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, > - clock_pair_gpa, > - KVM_CLOCK_PAIRING_WALLCLOCK); > - if (ret != 0) { > - pr_err_ratelimited("clock offset hypercall ret %lu\n", ret); > + ret = kvm_arch_ptp_get_clock(&tspec); > + if (ret) { > spin_unlock(&kvm_ptp_lock); > - return -EOPNOTSUPP; > + return ret; > } > > - tspec.tv_sec = clock_pair.sec; > - tspec.tv_nsec = clock_pair.nsec; > spin_unlock(&kvm_ptp_lock); > > memcpy(ts, &tspec, sizeof(struct timespec64)); > @@ -168,19 +136,11 @@ static int __init ptp_kvm_init(void) > { > long ret; > > - if (!kvm_para_available()) > - return -ENODEV; > - > - clock_pair_gpa = slow_virt_to_phys(&clock_pair); > - hv_clock = pvclock_get_pvti_cpu0_va(); > - > - if (!hv_clock) > - return -ENODEV; > - > - ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, clock_pair_gpa, > - KVM_CLOCK_PAIRING_WALLCLOCK); > - if (ret == -KVM_ENOSYS || ret == -KVM_EOPNOTSUPP) > - return -ENODEV; > + ret = kvm_arch_ptp_init(); > + if (ret) { > + pr_err("fail to initialize ptp_kvm"); > + return ret; > + } > > kvm_ptp_clock.caps = ptp_kvm_caps; > > diff --git a/drivers/ptp/ptp_kvm_x86.c b/drivers/ptp/ptp_kvm_x86.c > new file mode 100644 > index 000000000000..82a6be9a7479 > --- /dev/null > +++ b/drivers/ptp/ptp_kvm_x86.c > @@ -0,0 +1,97 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * Virtual PTP 1588 clock for use with KVM guests > + * > + * Copyright (C) 2017 Red Hat Inc. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +struct pvclock_vsyscall_time_info *hv_clock; > + > +static phys_addr_t clock_pair_gpa; > +static struct kvm_clock_pairing clock_pair; > + > +int kvm_arch_ptp_init(void) > +{ > + long ret; > + > + if (!kvm_para_available()) > + return -ENODEV; > + > + clock_pair_gpa = slow_virt_to_phys(&clock_pair); > + hv_clock = pvclock_get_pvti_cpu0_va(); > + if (!hv_clock) > + return -ENODEV; > + > + ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, clock_pair_gpa, > + KVM_CLOCK_PAIRING_WALLCLOCK); > + if (ret == -KVM_ENOSYS || ret == -KVM_EOPNOTSUPP) > + return -ENODEV; > + > + return 0; > +} > + > +int kvm_arch_ptp_get_clock(struct timespec64 *ts) > +{ > + unsigned long ret; Nit: The return value type of kvm_hypercall2 is signed, so you can use just "long" here. The former code used unsigned because ret was re-used again for another call. This is now gone. > + > + ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, > + clock_pair_gpa, > + KVM_CLOCK_PAIRING_WALLCLOCK); > + if (ret != 0) { > + pr_err_ratelimited("clock offset hypercall ret %lu\n", ret); > + return -EOPNOTSUPP; > + } > + > + ts->tv_sec = clock_pair.sec; > + ts->tv_nsec = clock_pair.nsec; > + > + return 0; > +} > + > +int kvm_arch_ptp_get_crosststamp(u64 *cycle, struct timespec64 *tspec, > + struct clocksource **cs) > +{ > + unsigned long ret; Same here. Cheers, Andre > + unsigned int version; > + int cpu; > + struct pvclock_vcpu_time_info *src; > + > + cpu = smp_processor_id(); > + src = &hv_clock[cpu].pvti; > + > + do { > + /* > + * We are using a TSC value read in the hosts > + * kvm_hc_clock_pairing handling. > + * So any changes to tsc_to_system_mul > + * and tsc_shift or any other pvclock > + * data invalidate that measurement. > + */ > + version = pvclock_read_begin(src); > + > + ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, > + clock_pair_gpa, > + KVM_CLOCK_PAIRING_WALLCLOCK); > + if (ret != 0) { > + pr_err_ratelimited("clock pairing hypercall ret %lu\n", ret); > + return -EOPNOTSUPP; > + } > + tspec->tv_sec = clock_pair.sec; > + tspec->tv_nsec = clock_pair.nsec; > + *cycle = __pvclock_read_cycles(src, clock_pair.tsc); > + } while (pvclock_read_retry(src, version)); > + > + *cs = &kvm_clock; > + > + return 0; > +} > diff --git a/include/linux/ptp_kvm.h b/include/linux/ptp_kvm.h > new file mode 100644 > index 000000000000..f960a719f0d5 > --- /dev/null > +++ b/include/linux/ptp_kvm.h > @@ -0,0 +1,19 @@ > +/* SPDX-License-Identifier: GPL-2.0-or-later */ > +/* > + * Virtual PTP 1588 clock for use with KVM guests > + * > + * Copyright (C) 2017 Red Hat Inc. > + */ > + > +#ifndef _PTP_KVM_H_ > +#define _PTP_KVM_H_ > + > +struct timespec64; > +struct clocksource; > + > +int kvm_arch_ptp_init(void); > +int kvm_arch_ptp_get_clock(struct timespec64 *ts); > +int kvm_arch_ptp_get_crosststamp(u64 *cycle, > + struct timespec64 *tspec, struct clocksource **cs); > + > +#endif /* _PTP_KVM_H_ */