From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ie0-x22a.google.com (mail-ie0-x22a.google.com [IPv6:2607:f8b0:4001:c03::22a]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 6C0A21A03BC for ; Thu, 16 Oct 2014 18:25:51 +1100 (AEDT) Received: by mail-ie0-f170.google.com with SMTP id rd18so2877354iec.29 for ; Thu, 16 Oct 2014 00:25:48 -0700 (PDT) From: kernelfans@gmail.com To: linuxppc-dev@lists.ozlabs.org, kvm-ppc@vger.kernel.org Subject: [RFC 03/11] powerpc: kvm: add interface to control kvm function on a core Date: Thu, 16 Oct 2014 15:29:52 -0400 Message-Id: <1413487800-7162-4-git-send-email-kernelfans@gmail.com> In-Reply-To: <1413487800-7162-1-git-send-email-kernelfans@gmail.com> References: <1413487800-7162-1-git-send-email-kernelfans@gmail.com> Cc: Paul Mackerras , Alexander Graf List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , When kvm is enabled on a core, we migrate all external irq to primary thread. Since currently, the kvmirq logic is handled by the primary hwthread. Todo: this patch lacks re-enable of irqbalance when kvm is disable on the core Signed-off-by: Liu Ping Fan --- arch/powerpc/kernel/sysfs.c | 39 ++++++++++++++++++++++++++++++++++ arch/powerpc/sysdev/xics/xics-common.c | 12 +++++++++++ 2 files changed, 51 insertions(+) diff --git a/arch/powerpc/kernel/sysfs.c b/arch/powerpc/kernel/sysfs.c index 67fd2fd..a2595dd 100644 --- a/arch/powerpc/kernel/sysfs.c +++ b/arch/powerpc/kernel/sysfs.c @@ -552,6 +552,45 @@ static void sysfs_create_dscr_default(void) if (cpu_has_feature(CPU_FTR_DSCR)) err = device_create_file(cpu_subsys.dev_root, &dev_attr_dscr_default); } + +#ifdef CONFIG_KVMPPC_ENABLE_SECONDARY +#define NR_CORES (CONFIG_NR_CPUS/threads_per_core) +static DECLARE_BITMAP(kvm_on_core, NR_CORES) __read_mostly + +static ssize_t show_kvm_enable(struct device *dev, + struct device_attribute *attr, char *buf) +{ +} + +static ssize_t __used store_kvm_enable(struct device *dev, + struct device_attribute *attr, const char *buf, + size_t count) +{ + struct cpumask stop_cpus; + unsigned long core, thr; + + sscanf(buf, "%lx", &core); + if (core > NR_CORES) + return -1; + if (!test_bit(core, &kvm_on_core)) + for (thr = 1; thr< threads_per_core; thr++) + if (cpu_online(thr * threads_per_core + thr)) + cpumask_set_cpu(thr * threads_per_core + thr, &stop_cpus); + + stop_machine(xics_migrate_irqs_away_secondary, NULL, &stop_cpus); + set_bit(core, &kvm_on_core); + return count; +} + +static DEVICE_ATTR(kvm_enable, 0600, + show_kvm_enable, store_kvm_enable); + +static void sysfs_create_kvm_enable(void) +{ + device_create_file(cpu_subsys.dev_root, &dev_attr_kvm_enable); +} +#endif + #endif /* CONFIG_PPC64 */ #ifdef HAS_PPC_PMC_PA6T diff --git a/arch/powerpc/sysdev/xics/xics-common.c b/arch/powerpc/sysdev/xics/xics-common.c index fe0cca4..68b33d8 100644 --- a/arch/powerpc/sysdev/xics/xics-common.c +++ b/arch/powerpc/sysdev/xics/xics-common.c @@ -258,6 +258,18 @@ unlock: raw_spin_unlock_irqrestore(&desc->lock, flags); } } + +int xics_migrate_irqs_away_secondary(void *data) +{ + int cpu = smp_processor_id(); + if(cpu%thread_per_core != 0) { + WARN(condition, format...); + return 0; + } + /* In fact, if we can migrate the primary, it will be more fine */ + xics_migrate_irqs_away(); + return 0; +} #endif /* CONFIG_HOTPLUG_CPU */ #ifdef CONFIG_SMP -- 1.8.3.1