Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1163111AbbKTPBK (ORCPT ); Fri, 20 Nov 2015 10:01:10 -0500 Received: from smtp.citrix.com ([66.165.176.89]:45281 "EHLO SMTP.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935176AbbKTO7x (ORCPT ); Fri, 20 Nov 2015 09:59:53 -0500 X-IronPort-AV: E=Sophos;i="5.20,323,1444694400"; d="scan'208";a="313659673" From: Stefano Stabellini To: CC: , , , , , , , , , , , Stefano Stabellini , Ian Campbell Subject: [PATCH v12 1/4] xen: move xen_setup_runstate_info and get_runstate_snapshot to drivers/xen/time.c Date: Fri, 20 Nov 2015 14:59:30 +0000 Message-ID: <1448031573-23497-1-git-send-email-stefano.stabellini@eu.citrix.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain X-DLP: MIA2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6511 Lines: 257 Signed-off-by: Stefano Stabellini Acked-by: Ian Campbell Reviewed-by: Konrad Rzeszutek Wilk CC: konrad.wilk@oracle.com --- Changes in v10: - rebase --- arch/x86/xen/time.c | 76 +---------------------------------------- drivers/xen/Makefile | 2 +- drivers/xen/time.c | 91 +++++++++++++++++++++++++++++++++++++++++++++++++ include/xen/xen-ops.h | 5 +++ 4 files changed, 98 insertions(+), 76 deletions(-) create mode 100644 drivers/xen/time.c diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c index f1ba6a0..041d4cd 100644 --- a/arch/x86/xen/time.c +++ b/arch/x86/xen/time.c @@ -32,86 +32,12 @@ #define TIMER_SLOP 100000 #define NS_PER_TICK (1000000000LL / HZ) -/* runstate info updated by Xen */ -static DEFINE_PER_CPU(struct vcpu_runstate_info, xen_runstate); - /* snapshots of runstate info */ static DEFINE_PER_CPU(struct vcpu_runstate_info, xen_runstate_snapshot); /* unused ns of stolen time */ static DEFINE_PER_CPU(u64, xen_residual_stolen); -/* return an consistent snapshot of 64-bit time/counter value */ -static u64 get64(const u64 *p) -{ - u64 ret; - - if (BITS_PER_LONG < 64) { - u32 *p32 = (u32 *)p; - u32 h, l; - - /* - * Read high then low, and then make sure high is - * still the same; this will only loop if low wraps - * and carries into high. - * XXX some clean way to make this endian-proof? - */ - do { - h = p32[1]; - barrier(); - l = p32[0]; - barrier(); - } while (p32[1] != h); - - ret = (((u64)h) << 32) | l; - } else - ret = *p; - - return ret; -} - -/* - * Runstate accounting - */ -static void get_runstate_snapshot(struct vcpu_runstate_info *res) -{ - u64 state_time; - struct vcpu_runstate_info *state; - - BUG_ON(preemptible()); - - state = this_cpu_ptr(&xen_runstate); - - /* - * The runstate info is always updated by the hypervisor on - * the current CPU, so there's no need to use anything - * stronger than a compiler barrier when fetching it. - */ - do { - state_time = get64(&state->state_entry_time); - barrier(); - *res = *state; - barrier(); - } while (get64(&state->state_entry_time) != state_time); -} - -/* return true when a vcpu could run but has no real cpu to run on */ -bool xen_vcpu_stolen(int vcpu) -{ - return per_cpu(xen_runstate, vcpu).state == RUNSTATE_runnable; -} - -void xen_setup_runstate_info(int cpu) -{ - struct vcpu_register_runstate_memory_area area; - - area.addr.v = &per_cpu(xen_runstate, cpu); - - if (HYPERVISOR_vcpu_op(VCPUOP_register_runstate_memory_area, - cpu, &area)) - BUG(); -} - static void do_stolen_accounting(void) { struct vcpu_runstate_info state; @@ -119,7 +45,7 @@ static void do_stolen_accounting(void) s64 runnable, offline, stolen; cputime_t ticks; - get_runstate_snapshot(&state); + xen_get_runstate_snapshot(&state); WARN_ON(state.state != RUNSTATE_running); diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile index aa8a7f7..9b7a35c 100644 --- a/drivers/xen/Makefile +++ b/drivers/xen/Makefile @@ -1,6 +1,6 @@ obj-$(CONFIG_HOTPLUG_CPU) += cpu_hotplug.o obj-$(CONFIG_X86) += fallback.o -obj-y += grant-table.o features.o balloon.o manage.o preempt.o +obj-y += grant-table.o features.o balloon.o manage.o preempt.o time.o obj-y += events/ obj-y += xenbus/ diff --git a/drivers/xen/time.c b/drivers/xen/time.c new file mode 100644 index 0000000..433fe24 --- /dev/null +++ b/drivers/xen/time.c @@ -0,0 +1,91 @@ +/* + * Xen stolen ticks accounting. + */ +#include +#include +#include +#include + +#include +#include + +#include +#include +#include +#include +#include + +/* runstate info updated by Xen */ +static DEFINE_PER_CPU(struct vcpu_runstate_info, xen_runstate); + +/* return an consistent snapshot of 64-bit time/counter value */ +static u64 get64(const u64 *p) +{ + u64 ret; + + if (BITS_PER_LONG < 64) { + u32 *p32 = (u32 *)p; + u32 h, l; + + /* + * Read high then low, and then make sure high is + * still the same; this will only loop if low wraps + * and carries into high. + * XXX some clean way to make this endian-proof? + */ + do { + h = p32[1]; + barrier(); + l = p32[0]; + barrier(); + } while (p32[1] != h); + + ret = (((u64)h) << 32) | l; + } else + ret = *p; + + return ret; +} + +/* + * Runstate accounting + */ +void xen_get_runstate_snapshot(struct vcpu_runstate_info *res) +{ + u64 state_time; + struct vcpu_runstate_info *state; + + BUG_ON(preemptible()); + + state = this_cpu_ptr(&xen_runstate); + + /* + * The runstate info is always updated by the hypervisor on + * the current CPU, so there's no need to use anything + * stronger than a compiler barrier when fetching it. + */ + do { + state_time = get64(&state->state_entry_time); + barrier(); + *res = *state; + barrier(); + } while (get64(&state->state_entry_time) != state_time); +} + +/* return true when a vcpu could run but has no real cpu to run on */ +bool xen_vcpu_stolen(int vcpu) +{ + return per_cpu(xen_runstate, vcpu).state == RUNSTATE_runnable; +} + +void xen_setup_runstate_info(int cpu) +{ + struct vcpu_register_runstate_memory_area area; + + area.addr.v = &per_cpu(xen_runstate, cpu); + + if (HYPERVISOR_vcpu_op(VCPUOP_register_runstate_memory_area, + cpu, &area)) + BUG(); +} + diff --git a/include/xen/xen-ops.h b/include/xen/xen-ops.h index e4e214a..86abe07 100644 --- a/include/xen/xen-ops.h +++ b/include/xen/xen-ops.h @@ -5,6 +5,7 @@ #include #include #include +#include DECLARE_PER_CPU(struct vcpu_info *, xen_vcpu); @@ -18,6 +19,10 @@ void xen_arch_suspend(void); void xen_resume_notifier_register(struct notifier_block *nb); void xen_resume_notifier_unregister(struct notifier_block *nb); +bool xen_vcpu_stolen(int vcpu); +void xen_setup_runstate_info(int cpu); +void xen_get_runstate_snapshot(struct vcpu_runstate_info *res); + int xen_setup_shutdown_event(void); extern unsigned long *xen_contiguous_bitmap; -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/