From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753215AbcDFOSJ (ORCPT ); Wed, 6 Apr 2016 10:18:09 -0400 Received: from mx2.suse.de ([195.135.220.15]:58327 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752953AbcDFOSG (ORCPT ); Wed, 6 Apr 2016 10:18:06 -0400 From: Juergen Gross To: linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org Cc: boris.ostrovsky@oracle.com, david.vrabel@citrix.com, mingo@redhat.com, peterz@infradead.org, Douglas_Warzecha@dell.com, pali.rohar@gmail.com, jdelvare@suse.com, linux@roeck-us.net, tglx@linutronix.de, hpa@zytor.com, jeremy@goop.org, chrisw@sous-sol.org, akataria@vmware.com, rusty@rustcorp.com.au, virtualization@lists.linux-foundation.org, x86@kernel.org, Juergen Gross Subject: [PATCH v5 2/6] virt, sched: add generic vcpu pinning support Date: Wed, 6 Apr 2016 16:17:42 +0200 Message-Id: <1459952266-3687-3-git-send-email-jgross@suse.com> X-Mailer: git-send-email 2.6.6 In-Reply-To: <1459952266-3687-1-git-send-email-jgross@suse.com> References: <1459952266-3687-1-git-send-email-jgross@suse.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add generic virtualization support for pinning the current vcpu to a specified physical cpu. As this operation isn't performance critical (a very limited set of operations like BIOS calls and SMIs is expected to need this) just add a hypervisor specific indirection. Signed-off-by: Juergen Gross --- V4: move this patch some places up in the series WARN_ONCE in case platform doesn't support pinning as requested by Peter Zijlstra V3: use getc_cpu()/put_cpu() as suggested by David Vrabel V2: adapt to using workqueues add include/linux/hypervisor.h to hide architecture specific stuff from generic kernel code In case paravirt maintainers don't want to be responsible for include/linux/hypervisor.h I could take it. --- MAINTAINERS | 1 + arch/x86/include/asm/hypervisor.h | 4 ++++ arch/x86/kernel/cpu/hypervisor.c | 11 +++++++++++ include/linux/hypervisor.h | 17 +++++++++++++++++ kernel/smp.c | 1 + kernel/up.c | 1 + 6 files changed, 35 insertions(+) create mode 100644 include/linux/hypervisor.h diff --git a/MAINTAINERS b/MAINTAINERS index 40eb1db..d3bde4f 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -8330,6 +8330,7 @@ S: Supported F: Documentation/virtual/paravirt_ops.txt F: arch/*/kernel/paravirt* F: arch/*/include/asm/paravirt.h +F: include/linux/hypervisor.h PARIDE DRIVERS FOR PARALLEL PORT IDE DEVICES M: Tim Waugh diff --git a/arch/x86/include/asm/hypervisor.h b/arch/x86/include/asm/hypervisor.h index 055ea99..67942b6 100644 --- a/arch/x86/include/asm/hypervisor.h +++ b/arch/x86/include/asm/hypervisor.h @@ -43,6 +43,9 @@ struct hypervisor_x86 { /* X2APIC detection (run once per boot) */ bool (*x2apic_available)(void); + + /* pin current vcpu to specified physical cpu (run rarely) */ + void (*pin_vcpu)(int); }; extern const struct hypervisor_x86 *x86_hyper; @@ -56,6 +59,7 @@ extern const struct hypervisor_x86 x86_hyper_kvm; extern void init_hypervisor(struct cpuinfo_x86 *c); extern void init_hypervisor_platform(void); extern bool hypervisor_x2apic_available(void); +extern void hypervisor_pin_vcpu(int cpu); #else static inline void init_hypervisor(struct cpuinfo_x86 *c) { } static inline void init_hypervisor_platform(void) { } diff --git a/arch/x86/kernel/cpu/hypervisor.c b/arch/x86/kernel/cpu/hypervisor.c index 73d391a..ff108f8 100644 --- a/arch/x86/kernel/cpu/hypervisor.c +++ b/arch/x86/kernel/cpu/hypervisor.c @@ -85,3 +85,14 @@ bool __init hypervisor_x2apic_available(void) x86_hyper->x2apic_available && x86_hyper->x2apic_available(); } + +void hypervisor_pin_vcpu(int cpu) +{ + if (!x86_hyper) + return; + + if (x86_hyper->pin_vcpu) + x86_hyper->pin_vcpu(cpu); + else + WARN_ONCE(1, "vcpu pinning requested but not supported!\n"); +} diff --git a/include/linux/hypervisor.h b/include/linux/hypervisor.h new file mode 100644 index 0000000..3fa5ef2 --- /dev/null +++ b/include/linux/hypervisor.h @@ -0,0 +1,17 @@ +#ifndef __LINUX_HYPEVISOR_H +#define __LINUX_HYPEVISOR_H + +/* + * Generic Hypervisor support + * Juergen Gross + */ + +#ifdef CONFIG_HYPERVISOR_GUEST +#include +#else +static inline void hypervisor_pin_vcpu(int cpu) +{ +} +#endif + +#endif /* __LINUX_HYPEVISOR_H */ diff --git a/kernel/smp.c b/kernel/smp.c index 7416544..9388064 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -14,6 +14,7 @@ #include #include #include +#include #include "smpboot.h" diff --git a/kernel/up.c b/kernel/up.c index 1760bf3..3ccee2b 100644 --- a/kernel/up.c +++ b/kernel/up.c @@ -6,6 +6,7 @@ #include #include #include +#include int smp_call_function_single(int cpu, void (*func) (void *info), void *info, int wait) -- 2.6.6