qemu-kvm.git uq/master queue

GIT PULL New Marcelo Tosatti 2 participants 8 messages Feb 3, 2010 – Feb 8, 2010 KVM

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Marcelo Tosatti

author

2010-02-03 23:57 UTC #0 lore raw

The following changes since commit 117f8eb81dfdf51a0418fbf6d260cbb72bcd4a9d:
Markus Armbruster (1):
qdev: Add rudimentary help for property value

are available in the git repository at:

git://git.kernel.org/pub/scm/virt/kvm/qemu-kvm.git uq/master

Jan Kiszka (4):
KVM: Request setting of nmi_pending and sipi_vector
KVM: x86: Fix up misreported CPU features
KVM: Make vmport KVM-compatible
KVM: Move and rename regs_modified

Marcelo Tosatti (1):
Fix incoming migration with iothread

Sheng Yang (1):
kvm: Flush coalesced MMIO buffer periodly

 cpu-all.h         |    2 ++
 cpu-defs.h        |    3 ++-
 exec.c            |    6 ++++++
 hw/vmport.c       |    3 +++
 kvm-all.c         |   36 +++++++++++++++++++++---------------
 kvm.h             |    1 +
 target-i386/kvm.c |   11 ++++++++++-
 vl.c              |    4 ++++
 8 files changed, 49 insertions(+), 17 deletions(-)

Marcelo Tosatti

author

2010-02-03 23:57 UTC #1 lore raw

PATCH 1/6 kvm: Flush coalesced MMIO buffer periodly

From: Sheng Yang <[email protected]>

The default action of coalesced MMIO is, cache the writing in buffer, until:
1. The buffer is full.
2. Or the exit to QEmu due to other reasons.

But this would result in a very late writing in some condition.
1. The each time write to MMIO content is small.
2. The writing interval is big.
3. No need for input or accessing other devices frequently.

This issue was observed in a experimental embbed system. The test image simply print "test" every 1 seconds. The output in QEmu meets expectation, but the output in KVM is delayed for seconds.

Per Avi's suggestion, I hooked flushing coalesced MMIO buffer in VGA update handler. By this way, We don't need vcpu explicit exit to QEmu to handle this issue.

Signed-off-by Sheng Yang <[email protected]>

Signed-off-by Marcelo Tosatti <[email protected]>

---
 cpu-all.h |    2 ++
 exec.c    |    6 ++++++
 kvm-all.c |   23 +++++++++++++++--------
 kvm.h     |    1 +
 vl.c      |    2 ++
 5 files changed, 26 insertions(+), 8 deletions(-)

cpu-all.h +2 -0

index 57b69f8..1ccc9a8 100644
@@ -915,6 +915,8 @@ void qemu_register_coalesced_mmio(target_phys_addr_t addr, ram_addr_t size);
 
 void qemu_unregister_coalesced_mmio(target_phys_addr_t addr, ram_addr_t size);
 
+void qemu_flush_coalesced_mmio_buffer(void);
+
 /*******************************************/
 /* host CPU ticks (if available) */

exec.c +6 -0

index 76831a1..67fabae 100644
@@ -2406,6 +2406,12 @@ void qemu_unregister_coalesced_mmio(target_phys_addr_t addr, ram_addr_t size)
         kvm_uncoalesce_mmio_region(addr, size);
 }
 
+void qemu_flush_coalesced_mmio_buffer(void)
+{
+    if (kvm_enabled())
+        kvm_flush_coalesced_mmio_buffer();
+}
+
 ram_addr_t qemu_ram_alloc(ram_addr_t size)
 {
     RAMBlock *new_block;

kvm-all.c +15 -8

index 15ec38e..f8350c9 100644
@@ -59,6 +59,9 @@ struct KVMState
     int vmfd;
     int regs_modified;
     int coalesced_mmio;
+#ifdef KVM_CAP_COALESCED_MMIO
+    struct kvm_coalesced_mmio_ring *coalesced_mmio_ring;
+#endif
     int broken_set_mem_region;
     int migration_log;
     int vcpu_events;

@@ -200,6 +203,12 @@ int kvm_init_vcpu(CPUState *env)
         goto err;
     }
 
+#ifdef KVM_CAP_COALESCED_MMIO
+    if (s->coalesced_mmio && !s->coalesced_mmio_ring)
+        s->coalesced_mmio_ring = (void *) env->kvm_run +
+		s->coalesced_mmio * PAGE_SIZE;
+#endif
+
     ret = kvm_arch_init_vcpu(env);
     if (ret == 0) {
         qemu_register_reset(kvm_reset_vcpu, env);

@@ -466,10 +475,10 @@ int kvm_init(int smp_cpus)
         goto err;
     }
 
+    s->coalesced_mmio = 0;
 #ifdef KVM_CAP_COALESCED_MMIO
     s->coalesced_mmio = kvm_check_extension(s, KVM_CAP_COALESCED_MMIO);
-#else
-    s->coalesced_mmio = 0;
+    s->coalesced_mmio_ring = NULL;
 #endif
 
     s->broken_set_mem_region = 1;

@@ -544,14 +553,12 @@ static int kvm_handle_io(uint16_t port, void *data, int direction, int size,
     return 1;
 }
 
-static void kvm_run_coalesced_mmio(CPUState *env, struct kvm_run *run)
+void kvm_flush_coalesced_mmio_buffer(void)
 {
 #ifdef KVM_CAP_COALESCED_MMIO
     KVMState *s = kvm_state;
-    if (s->coalesced_mmio) {
-        struct kvm_coalesced_mmio_ring *ring;
-
-        ring = (void *)run + (s->coalesced_mmio * TARGET_PAGE_SIZE);
+    if (s->coalesced_mmio_ring) {
+        struct kvm_coalesced_mmio_ring *ring = s->coalesced_mmio_ring;
         while (ring->first != ring->last) {
             struct kvm_coalesced_mmio *ent;

@@ -609,7 +616,7 @@ int kvm_cpu_exec(CPUState *env)
             abort();
         }
 
-        kvm_run_coalesced_mmio(env, run);
+        kvm_flush_coalesced_mmio_buffer();
 
         ret = 0; /* exit loop */
         switch (run->exit_reason) {

kvm.h +1 -0

index 1c93ac5..59cba18 100644
@@ -53,6 +53,7 @@ void kvm_setup_guest_memory(void *start, size_t size);
 
 int kvm_coalesce_mmio_region(target_phys_addr_t start, ram_addr_t size);
 int kvm_uncoalesce_mmio_region(target_phys_addr_t start, ram_addr_t size);
+void kvm_flush_coalesced_mmio_buffer(void);
 
 int kvm_insert_breakpoint(CPUState *current_env, target_ulong addr,
                           target_ulong len, int type);

vl.c +2 -0

index 39833fc..50f133d 100644
@@ -2996,6 +2996,7 @@ static void gui_update(void *opaque)
     DisplayState *ds = opaque;
     DisplayChangeListener *dcl = ds->listeners;
 
+    qemu_flush_coalesced_mmio_buffer();
     dpy_refresh(ds);
 
     while (dcl != NULL) {

@@ -3011,6 +3012,7 @@ static void nographic_update(void *opaque)
 {
     uint64_t interval = GUI_REFRESH_INTERVAL;
 
+    qemu_flush_coalesced_mmio_buffer();
     qemu_mod_timer(nographic_timer, interval + qemu_get_clock(rt_clock));
 }

Signature · 1 line

1.6.6

Marcelo Tosatti

author

2010-02-03 23:57 UTC #2 lore raw

PATCH 2/6 KVM: Request setting of nmi_pending and sipi_vector

In reply to Marcelo Tosatti

From: Jan Kiszka <[email protected]>

The final version of VCPU events in 2.6.33 will allow to skip nmi_pending and sipi_vector on KVM_SET_VCPU_EVENTS. For now let's write them unconditionally, which is unproblematic for upstream due to missing SMP support. Future version which enable SMP will write them only on reset.

Signed-off-by Jan Kiszka <[email protected]>

Signed-off-by Marcelo Tosatti <[email protected]>

---
 target-i386/kvm.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

target-i386/kvm.c +3 -0

index 5b093ce..b457b96 100644
@@ -794,6 +794,9 @@ static int kvm_put_vcpu_events(CPUState *env)
 
     events.sipi_vector = env->sipi_vector;
 
+    events.flags =
+        KVM_VCPUEVENT_VALID_NMI_PENDING | KVM_VCPUEVENT_VALID_SIPI_VECTOR;
+
     return kvm_vcpu_ioctl(env, KVM_SET_VCPU_EVENTS, &events);
 #else
     return 0;

Signature · 1 line

1.6.6

Marcelo Tosatti

author

2010-02-03 23:57 UTC #3 lore raw

PATCH 3/6 KVM: x86: Fix up misreported CPU features

In reply to Marcelo Tosatti

From: Jan Kiszka <[email protected]>

Quoted 1 line

From qemu-kvm: Kernels before 2.6.30 misreported some essential CPU

features via KVM_GET_SUPPORTED_CPUID. Fix them up.

Signed-off-by Jan Kiszka <[email protected]>

---
 target-i386/kvm.c |    8 +++++++-
 1 files changed, 7 insertions(+), 1 deletions(-)

target-i386/kvm.c +7 -1

index b457b96..0d08cd5 100644
@@ -99,12 +99,18 @@ uint32_t kvm_arch_get_supported_cpuid(CPUState *env, uint32_t function, int reg)
                 break;
             case R_EDX:
                 ret = cpuid->entries[i].edx;
-                if (function == 0x80000001) {
+                switch (function) {
+                case 1:
+                    /* KVM before 2.6.30 misreports the following features */
+                    ret |= CPUID_MTRR | CPUID_PAT | CPUID_MCE | CPUID_MCA;
+                    break;
+                case 0x80000001:
                     /* On Intel, kvm returns cpuid according to the Intel spec,
                      * so add missing bits according to the AMD spec:
                      */
                     cpuid_1_edx = kvm_arch_get_supported_cpuid(env, 1, R_EDX);
                     ret |= cpuid_1_edx & 0xdfeff7ff;
+                    break;
                 }
                 break;
             }

Signature · 1 line

1.6.6

Marcelo Tosatti

author

2010-02-03 23:57 UTC #4 lore raw

PATCH 4/6 KVM: Make vmport KVM-compatible

In reply to Marcelo Tosatti

From: Jan Kiszka <[email protected]>

The vmport "device" accesses the VCPU registers, so it requires proper cpu_synchronize_state. Add it to vmport_ioport_read, which also synchronizes vmport_ioport_write.

Signed-off-by Jan Kiszka <[email protected]>

---
 hw/vmport.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

hw/vmport.c +3 -0

index 884af3f..6c9d7c9 100644
@@ -25,6 +25,7 @@
 #include "isa.h"
 #include "pc.h"
 #include "sysemu.h"
+#include "kvm.h"
 
 //#define VMPORT_DEBUG

@@ -58,6 +59,8 @@ static uint32_t vmport_ioport_read(void *opaque, uint32_t addr)
     unsigned char command;
     uint32_t eax;
 
+    cpu_synchronize_state(env);
+
     eax = env->regs[R_EAX];
     if (eax != VMPORT_MAGIC)
         return eax;

Signature · 1 line

1.6.6

Marcelo Tosatti

author

2010-02-03 23:57 UTC #5 lore raw

PATCH 5/6 KVM: Move and rename regs_modified

In reply to Marcelo Tosatti

From: Jan Kiszka <[email protected]>

Touching the user space representation of KVM's VCPU state is - naturally - a per-VCPU thing. So move the dirty flag into KVM_CPU_COMMON and rename it at this chance to reflect its true meaning.

Signed-off-by Jan Kiszka <[email protected]>

---
 cpu-defs.h |    3 ++-
 kvm-all.c  |   13 ++++++-------
 2 files changed, 8 insertions(+), 8 deletions(-)

cpu-defs.h +2 -1

index 95068b5..7fdbe97 100644
@@ -197,6 +197,7 @@ typedef struct CPUWatchpoint {
     const char *cpu_model_str;                                          \
     struct KVMState *kvm_state;                                         \
     struct kvm_run *kvm_run;                                            \
-    int kvm_fd;
+    int kvm_fd;                                                         \
+    int kvm_vcpu_dirty;
 
 #endif

kvm-all.c +6 -7

index f8350c9..6c0fd37 100644
@@ -57,7 +57,6 @@ struct KVMState
     KVMSlot slots[32];
     int fd;
     int vmfd;
-    int regs_modified;
     int coalesced_mmio;
 #ifdef KVM_CAP_COALESCED_MMIO
     struct kvm_coalesced_mmio_ring *coalesced_mmio_ring;

@@ -574,9 +573,9 @@ void kvm_flush_coalesced_mmio_buffer(void)
 
 void kvm_cpu_synchronize_state(CPUState *env)
 {
-    if (!env->kvm_state->regs_modified) {
+    if (!env->kvm_vcpu_dirty) {
         kvm_arch_get_registers(env);
-        env->kvm_state->regs_modified = 1;
+        env->kvm_vcpu_dirty = 1;
     }
 }

@@ -594,9 +593,9 @@ int kvm_cpu_exec(CPUState *env)
             break;
         }
 
-        if (env->kvm_state->regs_modified) {
+        if (env->kvm_vcpu_dirty) {
             kvm_arch_put_registers(env);
-            env->kvm_state->regs_modified = 0;
+            env->kvm_vcpu_dirty = 0;
         }
 
         kvm_arch_pre_run(env, run);

@@ -946,9 +945,9 @@ static void kvm_invoke_set_guest_debug(void *data)
     struct kvm_set_guest_debug_data *dbg_data = data;
     CPUState *env = dbg_data->env;
 
-    if (env->kvm_state->regs_modified) {
+    if (env->kvm_vcpu_dirty) {
         kvm_arch_put_registers(env);
-        env->kvm_state->regs_modified = 0;
+        env->kvm_vcpu_dirty = 0;
     }
     dbg_data->err = kvm_vcpu_ioctl(env, KVM_SET_GUEST_DEBUG, &dbg_data->dbg);
 }

Signature · 1 line

1.6.6

Marcelo Tosatti

author

2010-02-03 23:57 UTC #6 lore raw

PATCH 6/6 Fix incoming migration with iothread

In reply to Marcelo Tosatti

Do not allow the vcpus to execute if the vm is stopped.

Fixes -incoming with CONFIG_IOTHREAD enabled.

Signed-off-by Marcelo Tosatti <[email protected]>

---
 vl.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

vl.c +2 -0

index 50f133d..57f0ba5 100644
@@ -3282,6 +3282,8 @@ static int cpu_can_run(CPUState *env)
         return 0;
     if (env->stopped)
         return 0;
+    if (!vm_running)
+        return 0;
     return 1;
 }

Signature · 1 line

1.6.6

Anthony Liguori

Applied

2010-02-08 16:44 UTC #7 lore raw

In reply to Marcelo Tosatti

Quoted 20 lines · Marcelo Tosatti

The following changes since commit 117f8eb81dfdf51a0418fbf6d260cbb72bcd4a9d:
Markus Armbruster (1):
qdev: Add rudimentary help for property value
are available in the git repository at:
git://git.kernel.org/pub/scm/virt/kvm/qemu-kvm.git uq/master
Jan Kiszka (4):
KVM: Request setting of nmi_pending and sipi_vector
KVM: x86: Fix up misreported CPU features
KVM: Make vmport KVM-compatible
KVM: Move and rename regs_modified
Marcelo Tosatti (1):
Fix incoming migration with iothread
Sheng Yang (1):
kvm: Flush coalesced MMIO buffer periodly

Quoted 10 lines

  cpu-all.h         |    2 ++
  cpu-defs.h        |    3 ++-
  exec.c            |    6 ++++++
  hw/vmport.c       |    3 +++
  kvm-all.c         |   36 +++++++++++++++++++++---------------
  kvm.h             |    1 +
  target-i386/kvm.c |   11 ++++++++++-
  vl.c              |    4 ++++
  8 files changed, 49 insertions(+), 17 deletions(-)

Applied. Thanks.

Regards,

Anthony Liguori