Message ID | 20130517010442.GB12928@somewhere (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Frederic Weisbecker <fweisbec@gmail.com> writes: > On Thu, May 16, 2013 at 12:52:03AM +0200, Frederic Weisbecker wrote: >> On Mon, Mar 25, 2013 at 02:14:20PM -0700, Kevin Hilman wrote: >> > Gleb Natapov <gleb@redhat.com> writes: >> > >> > > On Sun, Mar 24, 2013 at 02:44:26PM +0100, Frederic Weisbecker wrote: >> > >> 2013/3/21 Gleb Natapov <gleb@redhat.com>: >> > >> > Isn't is simpler for kernel/context_tracking.c to define empty >> > >> > __guest_enter()/__guest_exit() if !CONFIG_KVM. >> > >> >> > >> That doesn't look right. Off-cases are usually handled from the >> > >> headers, right? So that we avoid iffdeffery ugliness in core code. >> > > Lets put it in linux/context_tracking.h header then. >> > >> > Here's a version to do that. >> > >> > Kevin >> > >> > From d9d909394479dd7ff90b7bddb95a564945406719 Mon Sep 17 00:00:00 2001 >> > From: Kevin Hilman <khilman@linaro.org> >> > Date: Mon, 25 Mar 2013 14:12:41 -0700 >> > Subject: [PATCH v2] ontext_tracking: fix !CONFIG_KVM compile: add stub guest >> > enter/exit >> >> Sorry for my very delayed response... >> >> > >> > When KVM is not enabled, or not available on a platform, the KVM >> > headers should not be included. Instead, just define stub >> > __guest_[enter|exit] functions. >> >> May be it would be cleaner to move guest_enter/exit definitions altogether >> in linux/context_tracking.h >> >> After all that's where the implementation mostly belong to. >> >> Let me see if I can get that in shape. > > Does the following work for you? Nope. Since it still includs kvm_host.h on non-KVM builds, there is potential for problems. For example, on ARM (v3.10-rc1 + this patch) has this build error: CC kernel/context_tracking.o In file included from /work/kernel/linaro/nohz/arch/arm/include/asm/kvm_host.h:41:0, from /work/kernel/linaro/nohz/include/linux/kvm_host.h:34, from /work/kernel/linaro/nohz/kernel/context_tracking.c:18: /work/kernel/linaro/nohz/arch/arm/include/asm/kvm_vgic.h:38:6: warning: "CONFIG_KVM_ARM_MAX_VCPUS" is not defined [-Wundef] In file included from /work/kernel/linaro/nohz/arch/arm/include/asm/kvm_host.h:41:0, from /work/kernel/linaro/nohz/include/linux/kvm_host.h:34, from /work/kernel/linaro/nohz/kernel/context_tracking.c:18: /work/kernel/linaro/nohz/arch/arm/include/asm/kvm_vgic.h:59:11: error: 'CONFIG_KVM_ARM_MAX_VCPUS' undeclared here (not in a function) Kevin -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/include/linux/context_tracking.h b/include/linux/context_tracking.h index 365f4a6..fc09d7b 100644 --- a/include/linux/context_tracking.h +++ b/include/linux/context_tracking.h @@ -3,6 +3,7 @@ #include <linux/sched.h> #include <linux/percpu.h> +#include <linux/vtime.h> #include <asm/ptrace.h> struct context_tracking { @@ -19,6 +20,26 @@ struct context_tracking { } state; }; +static inline void __guest_enter(void) +{ + /* + * This is running in ioctl context so we can avoid + * the call to vtime_account() with its unnecessary idle check. + */ + vtime_account_system(current); + current->flags |= PF_VCPU; +} + +static inline void __guest_exit(void) +{ + /* + * This is running in ioctl context so we can avoid + * the call to vtime_account() with its unnecessary idle check. + */ + vtime_account_system(current); + current->flags &= ~PF_VCPU; +} + #ifdef CONFIG_CONTEXT_TRACKING DECLARE_PER_CPU(struct context_tracking, context_tracking); @@ -35,6 +56,9 @@ static inline bool context_tracking_active(void) extern void user_enter(void); extern void user_exit(void); +extern void guest_enter(void); +extern void guest_exit(void); + static inline enum ctx_state exception_enter(void) { enum ctx_state prev_ctx; @@ -57,6 +81,17 @@ extern void context_tracking_task_switch(struct task_struct *prev, static inline bool context_tracking_in_user(void) { return false; } static inline void user_enter(void) { } static inline void user_exit(void) { } + +static inline void guest_enter(void) +{ + __guest_enter(); +} + +static inline void guest_exit(void) +{ + __guest_exit(); +} + static inline enum ctx_state exception_enter(void) { return 0; } static inline void exception_exit(enum ctx_state prev_ctx) { } static inline void context_tracking_task_switch(struct task_struct *prev, diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index f0eea07..8db53cf 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -23,6 +23,7 @@ #include <linux/ratelimit.h> #include <linux/err.h> #include <linux/irqflags.h> +#include <linux/context_tracking.h> #include <asm/signal.h> #include <linux/kvm.h> @@ -760,42 +761,6 @@ static inline int kvm_iommu_unmap_guest(struct kvm *kvm) } #endif -static inline void __guest_enter(void) -{ - /* - * This is running in ioctl context so we can avoid - * the call to vtime_account() with its unnecessary idle check. - */ - vtime_account_system(current); - current->flags |= PF_VCPU; -} - -static inline void __guest_exit(void) -{ - /* - * This is running in ioctl context so we can avoid - * the call to vtime_account() with its unnecessary idle check. - */ - vtime_account_system(current); - current->flags &= ~PF_VCPU; -} - -#ifdef CONFIG_CONTEXT_TRACKING -extern void guest_enter(void); -extern void guest_exit(void); - -#else /* !CONFIG_CONTEXT_TRACKING */ -static inline void guest_enter(void) -{ - __guest_enter(); -} - -static inline void guest_exit(void) -{ - __guest_exit(); -} -#endif /* !CONFIG_CONTEXT_TRACKING */ - static inline void kvm_guest_enter(void) { unsigned long flags;