Date: Fri, 1 Apr 2016 06:17:57 +0000 (UTC) From: Sepherosa Ziehau <sephe@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r297481 - head/sys/dev/hyperv/vmbus Message-ID: <201604010617.u316HvJU013559@repo.freebsd.org>
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Author: sephe Date: Fri Apr 1 06:17:57 2016 New Revision: 297481 URL: https://svnweb.freebsd.org/changeset/base/297481 Log: hyperv: Register Hyper-V timer early enough for TSC freq calibration The i8254 simulation in Hyper-V is kinda broken and is not available in Generation 2 Hyper-V VMs, so Hyper-V timer must be registered early enough so that it can be used to do the TSC freq calibration. This fixes the notorious warning like this: calcru: runtime went backwards from 50 usec to 25 usec for pid 0 (kernel) Submitted by: Dexuan Cui <decui microsoft com> Reviewed by: kib, sephe Tested by: kib, sephe MFC after: 1 week Sponsored by: Microsoft OSTC Differential Revision: https://reviews.freebsd.org/D5778 Modified: head/sys/dev/hyperv/vmbus/hv_hv.c Modified: head/sys/dev/hyperv/vmbus/hv_hv.c ============================================================================== --- head/sys/dev/hyperv/vmbus/hv_hv.c Fri Apr 1 03:46:16 2016 (r297480) +++ head/sys/dev/hyperv/vmbus/hv_hv.c Fri Apr 1 06:17:57 2016 (r297481) @@ -36,6 +36,7 @@ __FBSDID("$FreeBSD$"); #include <sys/malloc.h> #include <sys/pcpu.h> #include <sys/timetc.h> +#include <sys/kernel.h> #include <machine/bus.h> #include <machine/md_var.h> #include <vm/vm.h> @@ -207,8 +208,6 @@ hv_vmbus_init(void) hv_vmbus_g_context.hypercall_page = virt_addr; - tc_init(&hv_timecounter); /* register virtual timecount */ - hv_et_init(); return (0); @@ -437,3 +436,14 @@ void hv_vmbus_synic_cleanup(void *arg) wrmsr(HV_X64_MSR_SIEFP, siefp.as_uint64_t); } +static void +hv_tc_init(void) +{ + if (vm_guest != VM_GUEST_HV) + return; + + /* register virtual timecounter */ + tc_init(&hv_timecounter); +} + +SYSINIT(hv_tc_init, SI_SUB_HYPERVISOR, SI_ORDER_FIRST, hv_tc_init, NULL);
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