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[Qemu-devel] [PATCH 25/40] xenner: kernel: KVM PV code
From: |
Alexander Graf |
Subject: |
[Qemu-devel] [PATCH 25/40] xenner: kernel: KVM PV code |
Date: |
Mon, 1 Nov 2010 16:01:38 +0100 |
Xenner uses KVM's PV functionality for timekeeping. If we don't find
KVM clocksource support, we try to emulate it as good as we can.
Signed-off-by: Alexander Graf <address@hidden>
---
pc-bios/xenner/xenner-pv.c | 186 ++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 186 insertions(+), 0 deletions(-)
create mode 100644 pc-bios/xenner/xenner-pv.c
diff --git a/pc-bios/xenner/xenner-pv.c b/pc-bios/xenner/xenner-pv.c
new file mode 100644
index 0000000..98218a9
--- /dev/null
+++ b/pc-bios/xenner/xenner-pv.c
@@ -0,0 +1,186 @@
+/*
+ * Copyright (C) Red Hat 2007
+ * Copyright (C) Novell Inc. 2010
+ *
+ * Author(s): Gerd Hoffmann <address@hidden>
+ * Alexander Graf <address@hidden>
+ *
+ * Xenner KVM PV integration
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; under version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "xenner.h"
+
+/* --------------------------------------------------------------------- */
+
+const char *feature_bits[32] = {
+ [ KVM_FEATURE_CLOCKSOURCE ] = "clocksource",
+ [ KVM_FEATURE_NOP_IO_DELAY ] = "nop-iodelay",
+ [ KVM_FEATURE_MMU_OP ] = "mmu-op",
+};
+
+int pv_have_clock;
+
+/* --------------------------------------------------------------------- */
+
+void pv_clock_update(int wakeup)
+{
+ static int wakeups;
+ static int update;
+
+ if (wakeup) {
+ /* after halt() -- update clock unconditionally */
+ update = 1;
+ wakeups++;
+ } else {
+ /* timer irq -- update only if needed */
+ update = (0 == wakeups);
+ wakeups = 0;
+ }
+
+ /* vmexit to userspace so xenner has a chance to update systime */
+ if (update) {
+ if (pv_have_clock) {
+ emudev_cmd(EMUDEV_CMD_NOP, 0);
+ } else {
+ struct xen_cpu *cpu = get_cpu();
+
+ cpu->v.vcpu_info->time.tsc_timestamp = rdtsc();
+ cpu->v.vcpu_info->time.system_time =
+ cpu->v.vcpu_info->time.tsc_timestamp;
+
+ cpu->v.vcpu_info->time.version+=2;
+ cpu->v.vcpu_info->time.tsc_timestamp = rdtsc();
+ cpu->v.vcpu_info->time.system_time =
+ cpu->v.vcpu_info->time.tsc_timestamp;
+ }
+ }
+}
+
+static void pv_clock_wall(void)
+{
+ uint64_t wall = EMU_PA(&shared_info.wc_version);
+
+ printk(1, "%s: register wall clock at 0x%" PRIx64 "\n",
+ __FUNCTION__, wall);
+
+ if (pv_have_clock) {
+ if (wrmsrl_safe(MSR_KVM_WALL_CLOCK, wall)) {
+ panic("MSR_KVM_WALL_CLOCK wrmsr failed", NULL);
+ }
+ } else {
+ shared_info.wc_version = 4;
+ shared_info.wc_sec = 0;
+ shared_info.wc_nsec = 0;
+ }
+
+ printk(1, "%s: v%d %d.%09d\n", __FUNCTION__,
+ shared_info.wc_version,
+ shared_info.wc_sec,
+ shared_info.wc_nsec);
+}
+
+void pv_clock_sys(struct xen_cpu *cpu)
+{
+ uint64_t sys = cpu->v.vcpu_info_pa + offsetof(struct vcpu_info, time);
+
+ printk(1, "%s: register vcpu %d clock at 0x%" PRIx64 "\n",
+ __FUNCTION__, cpu->id, sys);
+
+ if (pv_have_clock) {
+ if (wrmsrl_safe(MSR_KVM_SYSTEM_TIME, sys | 1)) {
+ panic("MSR_KVM_SYSTEM_TIME wrmsr failed", NULL);
+ }
+ } else {
+ /* fake data */
+ cpu->v.vcpu_info->time.tsc_to_system_mul = 1;
+ cpu->v.vcpu_info->time.version = 2;
+ cpu->v.vcpu_info->time.tsc_timestamp = rdtsc();
+ cpu->v.vcpu_info->time.system_time =
+ cpu->v.vcpu_info->time.tsc_timestamp;
+ cpu->v.vcpu_info->time.tsc_shift = 0;
+ }
+
+ printk(1, "%s: v%d sys %" PRIu64 " tsc %" PRIu64 " mul %u shift %d\n",
+ __FUNCTION__,
+ cpu->v.vcpu_info->time.version,
+ cpu->v.vcpu_info->time.system_time,
+ cpu->v.vcpu_info->time.tsc_timestamp,
+ cpu->v.vcpu_info->time.tsc_to_system_mul,
+ cpu->v.vcpu_info->time.tsc_shift);
+}
+
+/* --------------------------------------------------------------------- */
+
+void pv_write_cr3(struct xen_cpu *cpu, ureg_t cr3_mfn)
+{
+ ureg_t cr3 = frame_to_addr(cr3_mfn);
+
+#ifdef CONFIG_64BIT
+ if (cpu->user_mode) {
+ cpu->user_cr3_mfn = cr3_mfn;
+ } else {
+ cpu->kernel_cr3_mfn = cr3_mfn;
+ }
+#else
+ cpu->cr3_mfn = cr3_mfn;
+#endif
+
+ vminfo.faults[XEN_FAULT_OTHER_CR3_LOAD]++;
+ write_cr3(cr3);
+ return;
+}
+
+/* --------------------------------------------------------------------- */
+
+void pv_init(struct xen_cpu *cpu)
+{
+ char buf[128];
+ struct kvm_cpuid_entry entry;
+ uint32_t sig[3];
+ uint32_t features;
+
+ entry.function = KVM_CPUID_SIGNATURE;
+ real_cpuid(&entry);
+ sig[0] = entry.ebx;
+ sig[1] = entry.ecx;
+ sig[2] = entry.edx;
+ if (0 != memcmp((char*)sig, "KVMKVMKVM", 10)) {
+ printk(1, "%s: no kvm signature: \"%.12s\"\n",
+ __FUNCTION__, (char*)sig);
+ goto no_kvm;
+ }
+
+ entry.function = KVM_CPUID_FEATURES;
+ real_cpuid(&entry);
+ features = entry.eax;
+
+ snprintf(buf, sizeof(buf), "%s: cpu %d, signature \"%.12s\", features
0x%08x",
+ __FUNCTION__, cpu->id, (char*)sig, features);
+ print_bits(1, buf, features, features, feature_bits);
+
+ /* pv clocksource */
+ if (features & (1 << KVM_FEATURE_CLOCKSOURCE)) {
+ pv_have_clock = 1;
+ }
+
+no_kvm:
+ pv_clock_sys(cpu);
+ if (cpu->id == 0) {
+ pv_clock_wall();
+ }
+}
+
+/* --------------------------------------------------------------------- */
+
--
1.6.0.2
- Re: [Qemu-devel] [PATCH 14/40] xenner: kernel: Instruction emulator, (continued)
- [Qemu-devel] [PATCH 24/40] xenner: kernel: printk, Alexander Graf, 2010/11/01
- [Qemu-devel] [PATCH 25/40] xenner: kernel: KVM PV code,
Alexander Graf <=
- [Qemu-devel] [PATCH 02/40] elf: Add notes implementation, Alexander Graf, 2010/11/01
- Re: [Qemu-devel] [PATCH 02/40] elf: Add notes implementation, Blue Swirl, 2010/11/01
- Re: [Qemu-devel] [PATCH 02/40] elf: Add notes implementation, Stefan Weil, 2010/11/01
- Re: [Qemu-devel] [PATCH 02/40] elf: Add notes implementation, Alexander Graf, 2010/11/01
- Re: [Qemu-devel] [PATCH 02/40] elf: Add notes implementation, Stefan Weil, 2010/11/01
- Re: [Qemu-devel] [PATCH 02/40] elf: Add notes implementation, Alexander Graf, 2010/11/01
- [Qemu-devel] Re: [PATCH 02/40] elf: Add notes implementation, Paolo Bonzini, 2010/11/01
- Re: [Qemu-devel] [PATCH 02/40] elf: Add notes implementation, Stefan Weil, 2010/11/01
- Re: [Qemu-devel] [PATCH 02/40] elf: Add notes implementation, Michael Matz, 2010/11/02
[Qemu-devel] Re: [PATCH 02/40] elf: Add notes implementation, Paolo Bonzini, 2010/11/01