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CPU feature及依赖补丁
by Peng Liang 19 Aug '20

19 Aug '20

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reschedule the Virt sig meeting//FW: 转发：【Meeting Notice】Virt sig meeting Time: 2020-08-17 14:30-16:30
by Chenzhendong (alex) 14 Aug '20

14 Aug '20

Hi all, Due to the meeting time conflict, the Virt sig meeting time is changed to 14:30 p.m. on August 17. Sorry for any inconvenience. If you have any questions, please feel free to contact me. -------- 原始邮件 -------- 发件人： Meeting Book <uMeeting(a)huawei.com<mailto:uMeeting@huawei.com>> 日期： 2020年8月14日周五 10:39 收件人： zdchenhn(a)163.com<mailto:zdchenhn@163.com> 主题：【Meeting Notice】Virt sig meeting Time: 2020-08-17 14:30-16:30 Topic Virt sig meeting Time 2020-08-17 14:30-16:30((UTC+08:00)Beijing) Join Conference Join (External) >><https://welink-meeting.zoom.us/j/360440806> Meeting ID 360 440 806 Convener 陈振东 Tips: Dial the access number to join conference<http://app.huawei.com/eshare/voiceMeetings> 注：仅支持部分国家和地区。( Only some countries and regions are supported.) 如果加入会议提示“会议已结束或会议号不存在”，请在官网下载最新版本入会。立即下载<https://zoom.us/download> If a message is displayed, indicating that the meeting has ended or the meeting ID does not exist, download the latest meeting client and try again.Download<https://zoom.us/download>

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[PATCH hulk-4.19-next v3 00/17] KVM: arm64 support vCPU preempted check and PV qspinlock
by Zengruan Ye 13 Aug '20

13 Aug '20

From: y00379943 <yezengruan(a)huawei.com> This patch set aims to support the vCPU preempted check and PV qspinlock under KVM/arm64. Changes from v2: * Remove Wanpeng Li's patches from this patch set * Bunch of typo fixes. Changes from v1: * Fix pv_time_ops undeclared in drivers/xen/time.c * Fix native_queued_spin_lock_slowpath undeclared in arch/arm64/kernel/alternative.c Christoffer Dall (1): KVM: arm/arm64: Factor out hypercall handling from PSCI code Qian Cai (1): arm64/spinlock: fix a -Wunused-function warning Steven Price (3): KVM: Implement kvm_put_guest() arm/arm64: Provide a wrapper for SMCCC 1.1 calls arm/arm64: Make use of the SMCCC 1.1 wrapper Waiman Long (1): locking/osq: Use optimized spinning loop for arm64 Zengruan Ye (11): arm/paravirt: Use a single ops structure KVM: arm64: Document PV-sched interface KVM: arm64: Implement PV_SCHED_FEATURES call KVM: arm64: Support pvsched preempted via shared structure KVM: arm64: Add interface to support vCPU preempted check KVM: arm64: Support the vCPU preemption check KVM: arm64: Add SMCCC PV-sched to kick cpu KVM: arm64: Implement PV_SCHED_KICK_CPU call KVM: arm64: Add interface to support PV qspinlock KVM: arm64: Enable PV qspinlock KVM: arm64: Add tracepoints for PV qspinlock Documentation/virtual/kvm/arm/pvsched.txt | 64 +++++++ arch/arm/include/asm/kvm_host.h | 25 +++ arch/arm/include/asm/paravirt.h | 9 +- arch/arm/kernel/paravirt.c | 4 +- arch/arm/kvm/Makefile | 2 +- arch/arm/kvm/handle_exit.c | 2 +- arch/arm/mm/proc-v7-bugs.c | 13 +- arch/arm64/Kconfig | 14 ++ arch/arm64/include/asm/kvm_host.h | 20 ++ arch/arm64/include/asm/paravirt.h | 63 ++++++- arch/arm64/include/asm/pvsched-abi.h | 16 ++ arch/arm64/include/asm/qspinlock.h | 15 +- arch/arm64/include/asm/qspinlock_paravirt.h | 12 ++ arch/arm64/include/asm/spinlock.h | 26 +++ arch/arm64/kernel/Makefile | 3 +- arch/arm64/kernel/alternative.c | 5 +- arch/arm64/kernel/cpu_errata.c | 82 +++------ arch/arm64/kernel/paravirt-spinlocks.c | 18 ++ arch/arm64/kernel/paravirt.c | 192 +++++++++++++++++++- arch/arm64/kernel/setup.c | 2 + arch/arm64/kernel/trace-paravirt.h | 66 +++++++ arch/arm64/kvm/Makefile | 2 + arch/arm64/kvm/handle_exit.c | 5 +- drivers/xen/time.c | 4 + include/kvm/arm_hypercalls.h | 43 +++++ include/kvm/arm_psci.h | 2 +- include/linux/arm-smccc.h | 65 +++++++ include/linux/cpuhotplug.h | 1 + include/linux/kvm_host.h | 22 +++ include/linux/kvm_types.h | 2 + kernel/locking/osq_lock.c | 23 +-- virt/kvm/arm/arm.c | 12 +- virt/kvm/arm/hypercalls.c | 68 +++++++ virt/kvm/arm/psci.c | 76 +------- virt/kvm/arm/pvsched.c | 73 ++++++++ virt/kvm/arm/trace.h | 18 ++ 36 files changed, 899 insertions(+), 170 deletions(-) create mode 100644 Documentation/virtual/kvm/arm/pvsched.txt create mode 100644 arch/arm64/include/asm/pvsched-abi.h create mode 100644 arch/arm64/include/asm/qspinlock_paravirt.h create mode 100644 arch/arm64/kernel/paravirt-spinlocks.c create mode 100644 arch/arm64/kernel/trace-paravirt.h create mode 100644 include/kvm/arm_hypercalls.h create mode 100644 virt/kvm/arm/hypercalls.c create mode 100644 virt/kvm/arm/pvsched.c -- 2.19.1

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Virt sig会议议程纪要0731//RE: 【Meeting Notice】Virt sig meeting Time: 2020-07-31 14:30-16:30
by Chenzhendong (alex) 06 Aug '20

06 Aug '20

Virt sig会议议程纪要： 1、openEuler 20.09 虚拟化特性进展： a) KVM支持custom模式：整体进展80%，涉及两个组件：libvirt开发50%，qemu部分90%。 b) Vmtop：整体进展80%，用户态：将源码文件拆分，目录进行规范化，完成README以及相关文档；内核：检视后等待合入。 c) SmartPolling：整体进展80%，smartpoll的x86，已经检视通过，等待合入，arm的支持还在开发中。 d) PMU nmi watchdog：整体进展90%，开源方案分析完成，本地预验证通过，待版本验证。 e) 双层调度：整体进展80%，代码正在检视。 f) 安全启动：整体进展90%，edk2代码已经合入，待版本验证。 g) 可信启动：整体进展80%，qemu开源patch已经根据openEuler完成适配，验证功能中。 h) 轻量虚拟化：整体进展80%，基本功能开发完成，目前在进行可靠性、安全等增强。 2、EulerRobot质量体系构建进展： a) 当前Avocado-vt/tp-libvirt/tp-qemu等集成测试框架及用例，已经开源（见openEuler社区中相关仓库的openEuler-20.03分支）； b) crystal-ci平台在开发过程中，本地已经基于LKP调试对接了VT用例基本流程，待crystal-ci平台环境ready后即可与其快速对接。 3、virt 技术路标讨论： a) openEuler 20.09以后的特性待后续讨论。 From: Chenzhendong (alex) Sent: Thursday, July 30, 2020 3:10 PM To: 'dev(a)openeuler.org' <dev(a)openeuler.org>; 'tc(a)openeuler.org' <tc(a)openeuler.org>; 'virt(a)openeuler.org' <virt(a)openeuler.org> Cc: Zhangxiaofeng (F) <victor.zhangxiaofeng(a)huawei.com> Subject: 【Meeting Notice】Virt sig meeting Time: 2020-07-31 14:30-16:30 Virt sig会议议程： 1、openEuler 20.09 虚拟化特性进展 alexchen 2、EulerRobot质量体系构建进展 kuhnchen 3、virt 技术路标讨论 all -------- 原始邮件 -------- 发件人： Meeting Book <uMeeting(a)huawei.com<mailto:uMeeting@huawei.com>> 日期： 2020年7月30日周四 10:12 收件人： zdchenhn(a)163.com<mailto:zdchenhn@163.com> 主题：【Meeting Notice】Virt sig meeting Time: 2020-07-31 14:30-16:30 Topic Virt sig meeting Time 2020-07-31 14:30-16:30((UTC+08:00)Beijing) Join Conference Join (External) >><https://welink-meeting.zoom.us/j/623832541> Meeting ID 623 832 541 Convener 陈振东 Tips: Dial the access number to join conference<http://app.huawei.com/eshare/voiceMeetings> 注：仅支持部分国家和地区。( Only some countries and regions are supported.) 如果加入会议提示“会议已结束或会议号不存在”，请在官网下载最新版本入会。立即下载<https://zoom.us/download> If a message is displayed, indicating that the meeting has ended or the meeting ID does not exist, download the latest meeting client and try again.Download<https://zoom.us/download>

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[PATCH v5 1/2] hw/smbios: add options for type 4 max-speed and current-speed
by Ying Fang 05 Aug '20

05 Aug '20

Common VM users sometimes care about CPU speed, so we add two new options to allow VM vendors to present CPU speed to their users. Normally these information can be fetched from host smbios. Strictly speaking, the "max speed" and "current speed" in type 4 are not really for the max speed and current speed of processor, for "max speed" identifies a capability of the system, and "current speed" identifies the processor's speed at boot (see smbios spec), but some applications do not tell the differences. Signed-off-by: Ying Fang <fangying1(a)huawei.com> Signed-off-by: Heyi Guo <guoheyi(a)huawei.com> --- hw/smbios/smbios.c | 36 ++++++++++++++++++++++++++++++++---- qemu-options.hx | 2 +- 2 files changed, 33 insertions(+), 5 deletions(-) diff --git a/hw/smbios/smbios.c b/hw/smbios/smbios.c index 11d476c4a2..53181a58eb 100644 --- a/hw/smbios/smbios.c +++ b/hw/smbios/smbios.c @@ -93,9 +93,21 @@ static struct { const char *manufacturer, *version, *serial, *asset, *sku; } type3; +/* + * SVVP requires max_speed and current_speed to be set and not being + * 0 which counts as unknown (SMBIOS 3.1.0/Table 21). Set the + * default value to 2000MHz as we did before. + */ +#define DEFAULT_CPU_SPEED 2000 + static struct { const char *sock_pfx, *manufacturer, *version, *serial, *asset, *part; -} type4; + uint64_t max_speed; + uint64_t current_speed; +} type4 = { + .max_speed = DEFAULT_CPU_SPEED, + .current_speed = DEFAULT_CPU_SPEED +}; static struct { size_t nvalues; @@ -273,6 +285,14 @@ static const QemuOptDesc qemu_smbios_type4_opts[] = { .name = "version", .type = QEMU_OPT_STRING, .help = "version number", + },{ + .name = "max-speed", + .type = QEMU_OPT_NUMBER, + .help = "max speed in MHz", + },{ + .name = "current-speed", + .type = QEMU_OPT_NUMBER, + .help = "speed at system boot in MHz", },{ .name = "serial", .type = QEMU_OPT_STRING, @@ -587,9 +607,8 @@ static void smbios_build_type_4_table(MachineState *ms, unsigned instance) SMBIOS_TABLE_SET_STR(4, processor_version_str, type4.version); t->voltage = 0; t->external_clock = cpu_to_le16(0); /* Unknown */ - /* SVVP requires max_speed and current_speed to not be unknown. */ - t->max_speed = cpu_to_le16(2000); /* 2000 MHz */ - t->current_speed = cpu_to_le16(2000); /* 2000 MHz */ + t->max_speed = cpu_to_le16(type4.max_speed); + t->current_speed = cpu_to_le16(type4.current_speed); t->status = 0x41; /* Socket populated, CPU enabled */ t->processor_upgrade = 0x01; /* Other */ t->l1_cache_handle = cpu_to_le16(0xFFFF); /* N/A */ @@ -1130,6 +1149,15 @@ void smbios_entry_add(QemuOpts *opts, Error **errp) save_opt(&type4.serial, opts, "serial"); save_opt(&type4.asset, opts, "asset"); save_opt(&type4.part, opts, "part"); + type4.max_speed = qemu_opt_get_number(opts, "max-speed", + DEFAULT_CPU_SPEED); + type4.current_speed = qemu_opt_get_number(opts, "current-speed", + DEFAULT_CPU_SPEED); + if (type4.max_speed > UINT16_MAX || + type4.current_speed > UINT16_MAX) { + error_setg(errp, "SMBIOS CPU speed is too large (> %d)", + UINT16_MAX); + } return; case 11: qemu_opts_validate(opts, qemu_smbios_type11_opts, &err); diff --git a/qemu-options.hx b/qemu-options.hx index ea0638e92d..50b068423c 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -2073,7 +2073,7 @@ DEF("smbios", HAS_ARG, QEMU_OPTION_smbios, " [,sku=str]\n" " specify SMBIOS type 3 fields\n" "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n" - " [,asset=str][,part=str]\n" + " [,asset=str][,part=str][,max-speed=%d][,current-speed=%d]\n" " specify SMBIOS type 4 fields\n" "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n" " [,asset=str][,part=str][,speed=%d]\n" -- 2.23.0

1 1

[PATCH v5 0/2] add new options to set smbios type 4 fields
by Ying Fang 05 Aug '20

05 Aug '20

From: fangying <fangying1(a)huawei.com> Common VM users sometimes care about CPU speed, so we add two new options to allow VM vendors to present CPU speed to their users. Normally these information can be fetched from host smbios. --- v4 -> v3: - Rebase patch for lastest upstream v3 -> v4: - Fix the default value when not specifying "-smbios type=4" option; it would be 0 instead of 2000 in previous versions - Use uint64_t type to check value overflow - Add test case to check smbios type 4 CPU speed v2 -> v3: - Refine comments per Igor's suggestion. v1 -> v2: - change "_" in option names to "-" - check if option value is too large to fit in SMBIOS type 4 speed fields. --- Ying Fang (2): hw/smbios: add options for type 4 max-speed and current-speed tests/bios-tables-test: add smbios cpu speed test hw/smbios/smbios.c | 36 ++++++++++++++++++++++++++++++---- qemu-options.hx | 2 +- tests/bios-tables-test.c | 42 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 75 insertions(+), 5 deletions(-) -- 2.23.0

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[PATCH hulk-4.19-next] KVM: Check preempted_in_kernel for involuntary preemption
by Zengruan Ye 04 Aug '20

04 Aug '20

From: Wanpeng Li <wanpengli(a)tencent.com> mainline inclusion from mainline-v5.8-rc5 commit 046ddeed0461b5d270470c253cbb321103d048b6 category: feature bugzilla: NA DTS: NA CVE: NA -------------------------------- preempted_in_kernel is updated in preempt_notifier when involuntary preemption ocurrs, it can be stale when the voluntarily preempted vCPUs are taken into account by kvm_vcpu_on_spin() loop. This patch lets it just check preempted_in_kernel for involuntary preemption. Cc: Paolo Bonzini <pbonzini(a)redhat.com> Cc: Radim Krčmář <rkrcmar(a)redhat.com> Signed-off-by: Wanpeng Li <wanpengli(a)tencent.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> --- virt/kvm/kvm_main.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 887f3b0c2b60..ed061d8a457c 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2508,7 +2508,8 @@ void kvm_vcpu_on_spin(struct kvm_vcpu *me, bool yield_to_kernel_mode) continue; if (swait_active(&vcpu->wq) && !kvm_arch_vcpu_runnable(vcpu)) continue; - if (yield_to_kernel_mode && !kvm_arch_vcpu_in_kernel(vcpu)) + if (READ_ONCE(vcpu->preempted) && yield_to_kernel_mode && + !kvm_arch_vcpu_in_kernel(vcpu)) continue; if (!kvm_vcpu_eligible_for_directed_yield(vcpu)) continue; @@ -4205,7 +4206,7 @@ static void kvm_sched_in(struct preempt_notifier *pn, int cpu) { struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn); - vcpu->preempted = false; + WRITE_ONCE(vcpu->preempted, false); WRITE_ONCE(vcpu->ready, false); kvm_arch_sched_in(vcpu, cpu); @@ -4219,7 +4220,7 @@ static void kvm_sched_out(struct preempt_notifier *pn, struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn); if (current->state == TASK_RUNNING) { - vcpu->preempted = true; + WRITE_ONCE(vcpu->preempted, true); WRITE_ONCE(vcpu->ready, true); } kvm_arch_vcpu_put(vcpu); -- 2.19.1

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[PATCH hulk-4.19-next] KVM: Boost vCPUs that are delivering interrupts
by Zengruan Ye 04 Aug '20

04 Aug '20

From: Wanpeng Li <wanpengli(a)tencent.com> mainline inclusion from mainline-v5.8-rc5 commit d73eb57b80b98ae147e4e6a7d9877c2ba175f972 category: feature bugzilla: NA DTS: NA CVE: NA -------------------------------- Inspired by commit 9cac38dd5d (KVM/s390: Set preempted flag during vcpu wakeup and interrupt delivery), we want to also boost not just lock holders but also vCPUs that are delivering interrupts. Most smp_call_function_many calls are synchronous, so the IPI target vCPUs are also good yield candidates. This patch introduces vcpu->ready to boost vCPUs during wakeup and interrupt delivery time; unlike s390 we do not reuse vcpu->preempted so that voluntarily preempted vCPUs are taken into account by kvm_vcpu_on_spin, but vmx_vcpu_pi_put is not affected (VT-d PI handles voluntary preemption separately, in pi_pre_block). Testing on 80 HT 2 socket Xeon Skylake server, with 80 vCPUs VM 80GB RAM: ebizzy -M vanilla boosting improved 1VM 21443 23520 9% 2VM 2800 8000 180% 3VM 1800 3100 72% Testing on my Haswell desktop 8 HT, with 8 vCPUs VM 8GB RAM, two VMs, one running ebizzy -M, the other running 'stress --cpu 2': w/ boosting + w/o pv sched yield(vanilla) vanilla boosting improved 1570 4000 155% w/ boosting + w/ pv sched yield(vanilla) vanilla boosting improved 1844 5157 179% w/o boosting, perf top in VM: 72.33% [kernel] [k] smp_call_function_many 4.22% [kernel] [k] call_function_i 3.71% [kernel] [k] async_page_fault w/ boosting, perf top in VM: 38.43% [kernel] [k] smp_call_function_many 6.31% [kernel] [k] async_page_fault 6.13% libc-2.23.so [.] __memcpy_avx_unaligned 4.88% [kernel] [k] call_function_interrupt Cc: Paolo Bonzini <pbonzini(a)redhat.com> Cc: Radim Krčmář <rkrcmar(a)redhat.com> Cc: Christian Borntraeger <borntraeger(a)de.ibm.com> Cc: Paul Mackerras <paulus(a)ozlabs.org> Cc: Marc Zyngier <maz(a)kernel.org> Signed-off-by: Wanpeng Li <wanpengli(a)tencent.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> --- arch/s390/kvm/interrupt.c | 2 +- include/linux/kvm_host.h | 1 + virt/kvm/kvm_main.c | 12 ++++++++---- 3 files changed, 10 insertions(+), 5 deletions(-) diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c index 9dde4d7d8704..26f8bf4a22a7 100644 --- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -1240,7 +1240,7 @@ void kvm_s390_vcpu_wakeup(struct kvm_vcpu *vcpu) * The vcpu gave up the cpu voluntarily, mark it as a good * yield-candidate. */ - vcpu->preempted = true; + vcpu->ready = true; swake_up_one(&vcpu->wq); vcpu->stat.halt_wakeup++; } diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index c5da875f19e3..5c5b5867024c 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -318,6 +318,7 @@ struct kvm_vcpu { } spin_loop; #endif bool preempted; + bool ready; struct kvm_vcpu_arch arch; struct dentry *debugfs_dentry; }; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index b4ab59dd6846..887f3b0c2b60 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -314,6 +314,7 @@ int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id) kvm_vcpu_set_in_spin_loop(vcpu, false); kvm_vcpu_set_dy_eligible(vcpu, false); vcpu->preempted = false; + vcpu->ready = false; r = kvm_arch_vcpu_init(vcpu); if (r < 0) @@ -2387,6 +2388,7 @@ bool kvm_vcpu_wake_up(struct kvm_vcpu *vcpu) wqp = kvm_arch_vcpu_wq(vcpu); if (swq_has_sleeper(wqp)) { swake_up_one(wqp); + WRITE_ONCE(vcpu->ready, true); ++vcpu->stat.halt_wakeup; return true; } @@ -2500,7 +2502,7 @@ void kvm_vcpu_on_spin(struct kvm_vcpu *me, bool yield_to_kernel_mode) continue; } else if (pass && i > last_boosted_vcpu) break; - if (!READ_ONCE(vcpu->preempted)) + if (!READ_ONCE(vcpu->ready)) continue; if (vcpu == me) continue; @@ -4203,8 +4205,8 @@ static void kvm_sched_in(struct preempt_notifier *pn, int cpu) { struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn); - if (vcpu->preempted) - vcpu->preempted = false; + vcpu->preempted = false; + WRITE_ONCE(vcpu->ready, false); kvm_arch_sched_in(vcpu, cpu); @@ -4216,8 +4218,10 @@ static void kvm_sched_out(struct preempt_notifier *pn, { struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn); - if (current->state == TASK_RUNNING) + if (current->state == TASK_RUNNING) { vcpu->preempted = true; + WRITE_ONCE(vcpu->ready, true); + } kvm_arch_vcpu_put(vcpu); } -- 2.19.1

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【Meeting Notice】Virt sig meeting Time: 2020-07-31 14:30-16:30
by Chenzhendong (alex) 30 Jul '20

30 Jul '20

Virt sig会议议程： 1、openEuler 20.09 虚拟化特性进展 alexchen 2、EulerRobot质量体系构建进展 kuhnchen 3、virt 技术路标讨论 all -------- 原始邮件 -------- 发件人： Meeting Book <uMeeting(a)huawei.com<mailto:uMeeting@huawei.com>> 日期： 2020年7月30日周四 10:12 收件人： zdchenhn(a)163.com<mailto:zdchenhn@163.com> 主题：【Meeting Notice】Virt sig meeting Time: 2020-07-31 14:30-16:30 Topic Virt sig meeting Time 2020-07-31 14:30-16:30((UTC+08:00)Beijing) Join Conference Join (External) >><https://welink-meeting.zoom.us/j/623832541> Meeting ID 623 832 541 Convener 陈振东 Tips: Dial the access number to join conference<http://app.huawei.com/eshare/voiceMeetings> 注：仅支持部分国家和地区。( Only some countries and regions are supported.) 如果加入会议提示“会议已结束或会议号不存在”，请在官网下载最新版本入会。立即下载<https://zoom.us/download> If a message is displayed, indicating that the meeting has ended or the meeting ID does not exist, download the latest meeting client and try again.Download<https://zoom.us/download>

1 0

[PATCH] qcow2: flush qcow2 l2 meta for new allocated clusters
by Ying Fang 29 Jul '20

29 Jul '20

From: fangying <fangying1(a)huawei.com> When qemu or qemu-nbd process that uses a qcow2 file and configured with 'cache = none', it will write to the qcow2 file which uses qcow2 with a cache to cache L2 tables, the process will not use L2 tables without explicitly calling the flush command or closing the mirror flash into the disk. Which causes the disk data to be inconsistent with the written data for a long time. If an abnormal process exit occurs here, the written data will be lost. Therefore, we need to flush the changes to the L2 entry to the disk in time for the newly allocated cluster. Signed-off-by: Ying Fang <fangying1(a)huawei.com> diff --git a/block/qcow2-cache.c b/block/qcow2-cache.c index 7444b9c4ab..ab6e812c84 100644 --- a/block/qcow2-cache.c +++ b/block/qcow2-cache.c @@ -266,6 +266,22 @@ int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c) return result; } +#define L2_ENTRIES_PER_SECTOR 64 +int qcow2_cache_l2_write_entry(BlockDriverState *bs, Qcow2Cache *c, + void *table, int index, int num) +{ + int ret; + int i = qcow2_cache_get_table_idx(c, table); + int start_sector = index / L2_ENTRIES_PER_SECTOR; + int end_sector = (index + num - 1) / L2_ENTRIES_PER_SECTOR; + int nr_sectors = end_sector - start_sector + 1; + ret = bdrv_pwrite(bs->file, + c->entries[i].offset + start_sector * BDRV_SECTOR_SIZE, + table + start_sector * BDRV_SECTOR_SIZE, + nr_sectors * BDRV_SECTOR_SIZE); + return ret; +} + int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c, Qcow2Cache *dependency) { diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index a677ba9f5c..ae49a83972 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -998,6 +998,9 @@ int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m) } + ret = qcow2_cache_l2_write_entry(bs, s->l2_table_cache, l2_slice, + l2_index, m->nb_clusters); + qcow2_cache_put(s->l2_table_cache, (void **) &l2_slice); /* diff --git a/block/qcow2.h b/block/qcow2.h index 7ce2c23bdb..168ab5918e 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -748,6 +748,8 @@ int qcow2_cache_destroy(Qcow2Cache *c); void qcow2_cache_entry_mark_dirty(Qcow2Cache *c, void *table); int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c); int qcow2_cache_write(BlockDriverState *bs, Qcow2Cache *c); +int qcow2_cache_l2_write_entry(BlockDriverState *bs, Qcow2Cache *c, + void *table, int index, int num); int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c, Qcow2Cache *dependency); void qcow2_cache_depends_on_flush(Qcow2Cache *c); -- 2.23.0

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