[PATCH V5 0/4] introduce coalesced pio support

[PATCH V5 0/4] introduce coalesced pio support

[Peng Hao]

Coalesced pio is base on coalesced mmio and can be used for some port
like rtc port, pci-host config port, virtio-pci config port and so on.

Specially in case of rtc as coalesced pio, some versions of windows guest
access rtc frequently because of rtc as system tick. guest access rtc like
this: write register index to 0x70, then write or read data from 0x71.
writing 0x70 port is just as index and do nothing else. So we can use
coalesced pio to handle this scene to reduce VM-EXIT time.

When it starts and closes the virtual machine, it will access pci-host config
port or virtio-pci config port frequently. So setting these port as
coalesced pio can reduce startup and shutdown time. In qemu I just realize
piixfx's pci-host, it is convenient for other pci-host type implementations.

without my patch, get the vm-exit time of accessing rtc 0x70 and piix 0xcf8
using perf tools: (guest OS : windows 7 64bit)
IO Port Access  Samples Samples%  Time%  Min Time  Max Time  Avg time
0x70:POUT        86     30.99%    74.59%   9us      29us    10.75us (+- 3.41%)
0xcf8:POUT     1119     2.60%     2.12%   2.79us    56.83us 3.41us (+- 2.23%)

with my patch
IO Port Access  Samples Samples%  Time%   Min Time  Max Time   Avg time
0x70:POUT       106    32.02%    29.47%    0us      10us     1.57us (+- 7.38%)
0xcf8:POUT      1065    1.67%     0.28%   0.41us    65.44us   0.66us (+- 10.55%)

These are just qemu's patches, another patches are for kernel.

Changes v4 --> v5:
   update kvm header, improve compatibility.

Changes v3 --> v4
   modify coalesced_mmio_{add|del} to coalesced_io_{add|del}
   delete unnecessary macro define

Peng Hao (4):
  target-i386: introduce coalesced_pio kvm header update
  target-i386: add coalesced_pio API
  target-i386: add rtc 0x70 port as coalesced_pio
  target-i386: add i440fx 0xcf8 port as coalesced_pio

 accel/kvm/kvm-all.c       | 61 ++++++++++++++++++++++++++++++++++++++++++-----
 hw/pci-host/piix.c        |  4 ++++
 hw/timer/mc146818rtc.c    |  8 +++++++
 include/exec/memory.h     |  4 ++--
 linux-headers/linux/kvm.h | 11 +++++++--
 memory.c                  |  4 ++--
 6 files changed, 80 insertions(+), 12 deletions(-)

-- 
1.8.3.1

[Qemu-devel] [PATCH V5 0/4] introduce coalesced pio support

[Peng Hao]

Coalesced pio is base on coalesced mmio and can be used for some port
like rtc port, pci-host config port, virtio-pci config port and so on.

Specially in case of rtc as coalesced pio, some versions of windows guest
access rtc frequently because of rtc as system tick. guest access rtc like
this: write register index to 0x70, then write or read data from 0x71.
writing 0x70 port is just as index and do nothing else. So we can use
coalesced pio to handle this scene to reduce VM-EXIT time.

When it starts and closes the virtual machine, it will access pci-host config
port or virtio-pci config port frequently. So setting these port as
coalesced pio can reduce startup and shutdown time. In qemu I just realize
piixfx's pci-host, it is convenient for other pci-host type implementations.

without my patch, get the vm-exit time of accessing rtc 0x70 and piix 0xcf8
using perf tools: (guest OS : windows 7 64bit)
IO Port Access  Samples Samples%  Time%  Min Time  Max Time  Avg time
0x70:POUT        86     30.99%    74.59%   9us      29us    10.75us (+- 3.41%)
0xcf8:POUT     1119     2.60%     2.12%   2.79us    56.83us 3.41us (+- 2.23%)

with my patch
IO Port Access  Samples Samples%  Time%   Min Time  Max Time   Avg time
0x70:POUT       106    32.02%    29.47%    0us      10us     1.57us (+- 7.38%)
0xcf8:POUT      1065    1.67%     0.28%   0.41us    65.44us   0.66us (+- 10.55%)

These are just qemu's patches, another patches are for kernel.

Changes v4 --> v5:
   update kvm header, improve compatibility.

Changes v3 --> v4
   modify coalesced_mmio_{add|del} to coalesced_io_{add|del}
   delete unnecessary macro define

Peng Hao (4):
  target-i386: introduce coalesced_pio kvm header update
  target-i386: add coalesced_pio API
  target-i386: add rtc 0x70 port as coalesced_pio
  target-i386: add i440fx 0xcf8 port as coalesced_pio

 accel/kvm/kvm-all.c       | 61 ++++++++++++++++++++++++++++++++++++++++++-----
 hw/pci-host/piix.c        |  4 ++++
 hw/timer/mc146818rtc.c    |  8 +++++++
 include/exec/memory.h     |  4 ++--
 linux-headers/linux/kvm.h | 11 +++++++--
 memory.c                  |  4 ++--
 6 files changed, 80 insertions(+), 12 deletions(-)

-- 
1.8.3.1

[PATCH V5 1/4] target-i386: introduce coalesced_pio kvm header update

[Peng Hao]

add coalesced_pio's struct and KVM_CAP_COALESCED_PIO header.

Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
---
 accel/kvm/kvm-all.c       |  4 ++--
 linux-headers/linux/kvm.h | 11 +++++++++--
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index eb7db92..4a3909d 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -536,7 +536,7 @@ static void kvm_coalesce_mmio_region(MemoryListener *listener,
 
         zone.addr = start;
         zone.size = size;
-        zone.pad = 0;
+        zone.pio = 0;
 
         (void)kvm_vm_ioctl(s, KVM_REGISTER_COALESCED_MMIO, &zone);
     }
@@ -553,7 +553,7 @@ static void kvm_uncoalesce_mmio_region(MemoryListener *listener,
 
         zone.addr = start;
         zone.size = size;
-        zone.pad = 0;
+        zone.pio = 0;
 
         (void)kvm_vm_ioctl(s, KVM_UNREGISTER_COALESCED_MMIO, &zone);
     }
diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h
index 98f389a..1cb0d41 100644
--- a/linux-headers/linux/kvm.h
+++ b/linux-headers/linux/kvm.h
@@ -420,13 +420,19 @@ struct kvm_run {
 struct kvm_coalesced_mmio_zone {
 	__u64 addr;
 	__u32 size;
-	__u32 pad;
+	union {
+		__u32 pad;
+		__u32 pio;
+	};
 };
 
 struct kvm_coalesced_mmio {
 	__u64 phys_addr;
 	__u32 len;
-	__u32 pad;
+	union {
+		__u32 pad;
+		__u32 pio;
+	};
 	__u8  data[8];
 };
 
@@ -949,6 +955,7 @@ struct kvm_ppc_resize_hpt {
 #define KVM_CAP_GET_MSR_FEATURES 153
 #define KVM_CAP_HYPERV_EVENTFD 154
 #define KVM_CAP_HYPERV_TLBFLUSH 155
+#define KVM_CAP_COALESCED_PIO 156
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
-- 
1.8.3.1

[Qemu-devel] [PATCH V5 1/4] target-i386: introduce coalesced_pio kvm header update

[Peng Hao]

add coalesced_pio's struct and KVM_CAP_COALESCED_PIO header.

Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
---
 accel/kvm/kvm-all.c       |  4 ++--
 linux-headers/linux/kvm.h | 11 +++++++++--
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index eb7db92..4a3909d 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -536,7 +536,7 @@ static void kvm_coalesce_mmio_region(MemoryListener *listener,
 
         zone.addr = start;
         zone.size = size;
-        zone.pad = 0;
+        zone.pio = 0;
 
         (void)kvm_vm_ioctl(s, KVM_REGISTER_COALESCED_MMIO, &zone);
     }
@@ -553,7 +553,7 @@ static void kvm_uncoalesce_mmio_region(MemoryListener *listener,
 
         zone.addr = start;
         zone.size = size;
-        zone.pad = 0;
+        zone.pio = 0;
 
         (void)kvm_vm_ioctl(s, KVM_UNREGISTER_COALESCED_MMIO, &zone);
     }
diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h
index 98f389a..1cb0d41 100644
--- a/linux-headers/linux/kvm.h
+++ b/linux-headers/linux/kvm.h
@@ -420,13 +420,19 @@ struct kvm_run {
 struct kvm_coalesced_mmio_zone {
 	__u64 addr;
 	__u32 size;
-	__u32 pad;
+	union {
+		__u32 pad;
+		__u32 pio;
+	};
 };
 
 struct kvm_coalesced_mmio {
 	__u64 phys_addr;
 	__u32 len;
-	__u32 pad;
+	union {
+		__u32 pad;
+		__u32 pio;
+	};
 	__u8  data[8];
 };
 
@@ -949,6 +955,7 @@ struct kvm_ppc_resize_hpt {
 #define KVM_CAP_GET_MSR_FEATURES 153
 #define KVM_CAP_HYPERV_EVENTFD 154
 #define KVM_CAP_HYPERV_TLBFLUSH 155
+#define KVM_CAP_COALESCED_PIO 156
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
-- 
1.8.3.1

[PATCH V5 2/4] target-i386:add coalesced_pio API

[Peng Hao]

Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
---
 accel/kvm/kvm-all.c   | 57 +++++++++++++++++++++++++++++++++++++++++++++++----
 include/exec/memory.h |  4 ++--
 memory.c              |  4 ++--
 3 files changed, 57 insertions(+), 8 deletions(-)

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index 4a3909d..11d8d78 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -78,6 +78,7 @@ struct KVMState
     int fd;
     int vmfd;
     int coalesced_mmio;
+    int coalesced_pio;
     struct kvm_coalesced_mmio_ring *coalesced_mmio_ring;
     bool coalesced_flush_in_progress;
     int vcpu_events;
@@ -559,6 +560,45 @@ static void kvm_uncoalesce_mmio_region(MemoryListener *listener,
     }
 }
 
+static void kvm_coalesce_pio_add(MemoryListener *listener,
+                                MemoryRegionSection *section,
+                                hwaddr start, hwaddr size)
+{
+    KVMState *s = kvm_state;
+
+    if (s->coalesced_pio) {
+        struct kvm_coalesced_mmio_zone zone;
+
+        zone.addr = start;
+        zone.size = size;
+        zone.pio = 1;
+
+        (void)kvm_vm_ioctl(s, KVM_REGISTER_COALESCED_MMIO, &zone);
+    }
+}
+
+static void kvm_coalesce_pio_del(MemoryListener *listener,
+                                MemoryRegionSection *section,
+                                hwaddr start, hwaddr size)
+{
+    KVMState *s = kvm_state;
+
+    if (s->coalesced_pio) {
+        struct kvm_coalesced_mmio_zone zone;
+
+        zone.addr = start;
+        zone.size = size;
+        zone.pio = 1;
+
+        (void)kvm_vm_ioctl(s, KVM_UNREGISTER_COALESCED_MMIO, &zone);
+     }
+}
+
+static MemoryListener kvm_coalesced_pio_listener = {
+    .coalesced_io_add = kvm_coalesce_pio_add,
+    .coalesced_io_del = kvm_coalesce_pio_del,
+};
+
 int kvm_check_extension(KVMState *s, unsigned int extension)
 {
     int ret;
@@ -1615,6 +1655,8 @@ static int kvm_init(MachineState *ms)
     }
 
     s->coalesced_mmio = kvm_check_extension(s, KVM_CAP_COALESCED_MMIO);
+    s->coalesced_pio = s->coalesced_mmio &&
+                       kvm_check_extension(s, KVM_CAP_COALESCED_PIO);
 
 #ifdef KVM_CAP_VCPU_EVENTS
     s->vcpu_events = kvm_check_extension(s, KVM_CAP_VCPU_EVENTS);
@@ -1687,13 +1729,15 @@ static int kvm_init(MachineState *ms)
         s->memory_listener.listener.eventfd_add = kvm_mem_ioeventfd_add;
         s->memory_listener.listener.eventfd_del = kvm_mem_ioeventfd_del;
     }
-    s->memory_listener.listener.coalesced_mmio_add = kvm_coalesce_mmio_region;
-    s->memory_listener.listener.coalesced_mmio_del = kvm_uncoalesce_mmio_region;
+    s->memory_listener.listener.coalesced_io_add = kvm_coalesce_mmio_region;
+    s->memory_listener.listener.coalesced_io_del = kvm_uncoalesce_mmio_region;
 
     kvm_memory_listener_register(s, &s->memory_listener,
                                  &address_space_memory, 0);
     memory_listener_register(&kvm_io_listener,
                              &address_space_io);
+    memory_listener_register(&kvm_coalesced_pio_listener,
+                             &address_space_io);
 
     s->many_ioeventfds = kvm_check_many_ioeventfds();
 
@@ -1775,8 +1819,13 @@ void kvm_flush_coalesced_mmio_buffer(void)
             struct kvm_coalesced_mmio *ent;
 
             ent = &ring->coalesced_mmio[ring->first];
-
-            cpu_physical_memory_write(ent->phys_addr, ent->data, ent->len);
+            if (ent->pio == 1) {
+                address_space_rw(&address_space_io, ent->phys_addr,
+                                 MEMTXATTRS_UNSPECIFIED, ent->data,
+                                 ent->len, true);
+            } else {
+                cpu_physical_memory_write(ent->phys_addr, ent->data, ent->len);
+            }
             smp_wmb();
             ring->first = (ring->first + 1) % KVM_COALESCED_MMIO_MAX;
         }
diff --git a/include/exec/memory.h b/include/exec/memory.h
index 448d41a..4600fa3 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -410,9 +410,9 @@ struct MemoryListener {
                         bool match_data, uint64_t data, EventNotifier *e);
     void (*eventfd_del)(MemoryListener *listener, MemoryRegionSection *section,
                         bool match_data, uint64_t data, EventNotifier *e);
-    void (*coalesced_mmio_add)(MemoryListener *listener, MemoryRegionSection *section,
+    void (*coalesced_io_add)(MemoryListener *listener, MemoryRegionSection *section,
                                hwaddr addr, hwaddr len);
-    void (*coalesced_mmio_del)(MemoryListener *listener, MemoryRegionSection *section,
+    void (*coalesced_io_del)(MemoryListener *listener, MemoryRegionSection *section,
                                hwaddr addr, hwaddr len);
     /* Lower = earlier (during add), later (during del) */
     unsigned priority;
diff --git a/memory.c b/memory.c
index e9cd446..8b0311e 100644
--- a/memory.c
+++ b/memory.c
@@ -2126,7 +2126,7 @@ static void memory_region_update_coalesced_range_as(MemoryRegion *mr, AddressSpa
                 .size = fr->addr.size,
             };
 
-            MEMORY_LISTENER_CALL(as, coalesced_mmio_del, Reverse, &section,
+            MEMORY_LISTENER_CALL(as, coalesced_io_del, Reverse, &section,
                                  int128_get64(fr->addr.start),
                                  int128_get64(fr->addr.size));
             QTAILQ_FOREACH(cmr, &mr->coalesced, link) {
@@ -2137,7 +2137,7 @@ static void memory_region_update_coalesced_range_as(MemoryRegion *mr, AddressSpa
                     continue;
                 }
                 tmp = addrrange_intersection(tmp, fr->addr);
-                MEMORY_LISTENER_CALL(as, coalesced_mmio_add, Forward, &section,
+                MEMORY_LISTENER_CALL(as, coalesced_io_add, Forward, &section,
                                      int128_get64(tmp.start),
                                      int128_get64(tmp.size));
             }
-- 
1.8.3.1

[Qemu-devel] [PATCH V5 2/4] target-i386:add coalesced_pio API

[Peng Hao]

Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
---
 accel/kvm/kvm-all.c   | 57 +++++++++++++++++++++++++++++++++++++++++++++++----
 include/exec/memory.h |  4 ++--
 memory.c              |  4 ++--
 3 files changed, 57 insertions(+), 8 deletions(-)

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index 4a3909d..11d8d78 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -78,6 +78,7 @@ struct KVMState
     int fd;
     int vmfd;
     int coalesced_mmio;
+    int coalesced_pio;
     struct kvm_coalesced_mmio_ring *coalesced_mmio_ring;
     bool coalesced_flush_in_progress;
     int vcpu_events;
@@ -559,6 +560,45 @@ static void kvm_uncoalesce_mmio_region(MemoryListener *listener,
     }
 }
 
+static void kvm_coalesce_pio_add(MemoryListener *listener,
+                                MemoryRegionSection *section,
+                                hwaddr start, hwaddr size)
+{
+    KVMState *s = kvm_state;
+
+    if (s->coalesced_pio) {
+        struct kvm_coalesced_mmio_zone zone;
+
+        zone.addr = start;
+        zone.size = size;
+        zone.pio = 1;
+
+        (void)kvm_vm_ioctl(s, KVM_REGISTER_COALESCED_MMIO, &zone);
+    }
+}
+
+static void kvm_coalesce_pio_del(MemoryListener *listener,
+                                MemoryRegionSection *section,
+                                hwaddr start, hwaddr size)
+{
+    KVMState *s = kvm_state;
+
+    if (s->coalesced_pio) {
+        struct kvm_coalesced_mmio_zone zone;
+
+        zone.addr = start;
+        zone.size = size;
+        zone.pio = 1;
+
+        (void)kvm_vm_ioctl(s, KVM_UNREGISTER_COALESCED_MMIO, &zone);
+     }
+}
+
+static MemoryListener kvm_coalesced_pio_listener = {
+    .coalesced_io_add = kvm_coalesce_pio_add,
+    .coalesced_io_del = kvm_coalesce_pio_del,
+};
+
 int kvm_check_extension(KVMState *s, unsigned int extension)
 {
     int ret;
@@ -1615,6 +1655,8 @@ static int kvm_init(MachineState *ms)
     }
 
     s->coalesced_mmio = kvm_check_extension(s, KVM_CAP_COALESCED_MMIO);
+    s->coalesced_pio = s->coalesced_mmio &&
+                       kvm_check_extension(s, KVM_CAP_COALESCED_PIO);
 
 #ifdef KVM_CAP_VCPU_EVENTS
     s->vcpu_events = kvm_check_extension(s, KVM_CAP_VCPU_EVENTS);
@@ -1687,13 +1729,15 @@ static int kvm_init(MachineState *ms)
         s->memory_listener.listener.eventfd_add = kvm_mem_ioeventfd_add;
         s->memory_listener.listener.eventfd_del = kvm_mem_ioeventfd_del;
     }
-    s->memory_listener.listener.coalesced_mmio_add = kvm_coalesce_mmio_region;
-    s->memory_listener.listener.coalesced_mmio_del = kvm_uncoalesce_mmio_region;
+    s->memory_listener.listener.coalesced_io_add = kvm_coalesce_mmio_region;
+    s->memory_listener.listener.coalesced_io_del = kvm_uncoalesce_mmio_region;
 
     kvm_memory_listener_register(s, &s->memory_listener,
                                  &address_space_memory, 0);
     memory_listener_register(&kvm_io_listener,
                              &address_space_io);
+    memory_listener_register(&kvm_coalesced_pio_listener,
+                             &address_space_io);
 
     s->many_ioeventfds = kvm_check_many_ioeventfds();
 
@@ -1775,8 +1819,13 @@ void kvm_flush_coalesced_mmio_buffer(void)
             struct kvm_coalesced_mmio *ent;
 
             ent = &ring->coalesced_mmio[ring->first];
-
-            cpu_physical_memory_write(ent->phys_addr, ent->data, ent->len);
+            if (ent->pio == 1) {
+                address_space_rw(&address_space_io, ent->phys_addr,
+                                 MEMTXATTRS_UNSPECIFIED, ent->data,
+                                 ent->len, true);
+            } else {
+                cpu_physical_memory_write(ent->phys_addr, ent->data, ent->len);
+            }
             smp_wmb();
             ring->first = (ring->first + 1) % KVM_COALESCED_MMIO_MAX;
         }
diff --git a/include/exec/memory.h b/include/exec/memory.h
index 448d41a..4600fa3 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -410,9 +410,9 @@ struct MemoryListener {
                         bool match_data, uint64_t data, EventNotifier *e);
     void (*eventfd_del)(MemoryListener *listener, MemoryRegionSection *section,
                         bool match_data, uint64_t data, EventNotifier *e);
-    void (*coalesced_mmio_add)(MemoryListener *listener, MemoryRegionSection *section,
+    void (*coalesced_io_add)(MemoryListener *listener, MemoryRegionSection *section,
                                hwaddr addr, hwaddr len);
-    void (*coalesced_mmio_del)(MemoryListener *listener, MemoryRegionSection *section,
+    void (*coalesced_io_del)(MemoryListener *listener, MemoryRegionSection *section,
                                hwaddr addr, hwaddr len);
     /* Lower = earlier (during add), later (during del) */
     unsigned priority;
diff --git a/memory.c b/memory.c
index e9cd446..8b0311e 100644
--- a/memory.c
+++ b/memory.c
@@ -2126,7 +2126,7 @@ static void memory_region_update_coalesced_range_as(MemoryRegion *mr, AddressSpa
                 .size = fr->addr.size,
             };
 
-            MEMORY_LISTENER_CALL(as, coalesced_mmio_del, Reverse, &section,
+            MEMORY_LISTENER_CALL(as, coalesced_io_del, Reverse, &section,
                                  int128_get64(fr->addr.start),
                                  int128_get64(fr->addr.size));
             QTAILQ_FOREACH(cmr, &mr->coalesced, link) {
@@ -2137,7 +2137,7 @@ static void memory_region_update_coalesced_range_as(MemoryRegion *mr, AddressSpa
                     continue;
                 }
                 tmp = addrrange_intersection(tmp, fr->addr);
-                MEMORY_LISTENER_CALL(as, coalesced_mmio_add, Forward, &section,
+                MEMORY_LISTENER_CALL(as, coalesced_io_add, Forward, &section,
                                      int128_get64(tmp.start),
                                      int128_get64(tmp.size));
             }
-- 
1.8.3.1

[PATCH V5 3/4] target-i386: add rtc 0x70 port as coalesced_pio

[Peng Hao]

Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
---
 hw/timer/mc146818rtc.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/hw/timer/mc146818rtc.c b/hw/timer/mc146818rtc.c
index 6f1f723..b19ef51 100644
--- a/hw/timer/mc146818rtc.c
+++ b/hw/timer/mc146818rtc.c
@@ -70,6 +70,7 @@ typedef struct RTCState {
     ISADevice parent_obj;
 
     MemoryRegion io;
+    MemoryRegion coalesced_io;
     uint8_t cmos_data[128];
     uint8_t cmos_index;
     int32_t base_year;
@@ -990,6 +991,13 @@ static void rtc_realizefn(DeviceState *dev, Error **errp)
     memory_region_init_io(&s->io, OBJECT(s), &cmos_ops, s, "rtc", 2);
     isa_register_ioport(isadev, &s->io, base);
 
+    /* register rtc 0x70 port as coalesced_pio */
+    memory_region_set_flush_coalesced(&s->io);
+    memory_region_init_io(&s->coalesced_io, OBJECT(s), &cmos_ops,
+                          s, "rtc1", 1);
+    isa_register_ioport(isadev, &s->coalesced_io, base);
+    memory_region_add_coalescing(&s->coalesced_io, 0, 1);
+
     qdev_set_legacy_instance_id(dev, base, 3);
     qemu_register_reset(rtc_reset, s);
 
-- 
1.8.3.1

[Qemu-devel] [PATCH V5 3/4] target-i386: add rtc 0x70 port as coalesced_pio

[Peng Hao]

Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
---
 hw/timer/mc146818rtc.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/hw/timer/mc146818rtc.c b/hw/timer/mc146818rtc.c
index 6f1f723..b19ef51 100644
--- a/hw/timer/mc146818rtc.c
+++ b/hw/timer/mc146818rtc.c
@@ -70,6 +70,7 @@ typedef struct RTCState {
     ISADevice parent_obj;
 
     MemoryRegion io;
+    MemoryRegion coalesced_io;
     uint8_t cmos_data[128];
     uint8_t cmos_index;
     int32_t base_year;
@@ -990,6 +991,13 @@ static void rtc_realizefn(DeviceState *dev, Error **errp)
     memory_region_init_io(&s->io, OBJECT(s), &cmos_ops, s, "rtc", 2);
     isa_register_ioport(isadev, &s->io, base);
 
+    /* register rtc 0x70 port as coalesced_pio */
+    memory_region_set_flush_coalesced(&s->io);
+    memory_region_init_io(&s->coalesced_io, OBJECT(s), &cmos_ops,
+                          s, "rtc1", 1);
+    isa_register_ioport(isadev, &s->coalesced_io, base);
+    memory_region_add_coalescing(&s->coalesced_io, 0, 1);
+
     qdev_set_legacy_instance_id(dev, base, 3);
     qemu_register_reset(rtc_reset, s);
 
-- 
1.8.3.1

[PATCH V5 4/4] target-i386: add i440fx 0xcf8 port as coalesced_pio

[Peng Hao]

Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
---
 hw/pci-host/piix.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c
index 0e60834..da73743 100644
--- a/hw/pci-host/piix.c
+++ b/hw/pci-host/piix.c
@@ -327,6 +327,10 @@ static void i440fx_pcihost_realize(DeviceState *dev, Error **errp)
 
     sysbus_add_io(sbd, 0xcfc, &s->data_mem);
     sysbus_init_ioports(sbd, 0xcfc, 4);
+
+    /* register i440fx 0xcf8 port as coalesced pio */
+    memory_region_set_flush_coalesced(&s->data_mem);
+    memory_region_add_coalescing(&s->conf_mem, 0, 4);
 }
 
 static void i440fx_realize(PCIDevice *dev, Error **errp)
-- 
1.8.3.1

[Qemu-devel] [PATCH V5 4/4] target-i386: add i440fx 0xcf8 port as coalesced_pio

[Peng Hao]

Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
---
 hw/pci-host/piix.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c
index 0e60834..da73743 100644
--- a/hw/pci-host/piix.c
+++ b/hw/pci-host/piix.c
@@ -327,6 +327,10 @@ static void i440fx_pcihost_realize(DeviceState *dev, Error **errp)
 
     sysbus_add_io(sbd, 0xcfc, &s->data_mem);
     sysbus_init_ioports(sbd, 0xcfc, 4);
+
+    /* register i440fx 0xcf8 port as coalesced pio */
+    memory_region_set_flush_coalesced(&s->data_mem);
+    memory_region_add_coalescing(&s->conf_mem, 0, 4);
 }
 
 static void i440fx_realize(PCIDevice *dev, Error **errp)
-- 
1.8.3.1

Re: [PATCH V5 1/4] target-i386: introduce coalesced_pio kvm header update

[Eduardo Habkost]

On Thu, Aug 30, 2018 at 11:50:13PM +0800, Peng Hao wrote:
> add coalesced_pio's struct and KVM_CAP_COALESCED_PIO header.
> 
> Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>

I think there was a misunderstanding. I never sent a Reviewed-by
line for this patch, because we need to get the KVM patch
accepted before including this.

-- 
Eduardo

Re: [Qemu-devel] [PATCH V5 1/4] target-i386: introduce coalesced_pio kvm header update

[Eduardo Habkost]

On Thu, Aug 30, 2018 at 11:50:13PM +0800, Peng Hao wrote:
> add coalesced_pio's struct and KVM_CAP_COALESCED_PIO header.
> 
> Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>

I think there was a misunderstanding. I never sent a Reviewed-by
line for this patch, because we need to get the KVM patch
accepted before including this.

-- 
Eduardo

Re: [PATCH V5 3/4] target-i386: add rtc 0x70 port as coalesced_pio

[Eduardo Habkost]

On Thu, Aug 30, 2018 at 11:50:15PM +0800, Peng Hao wrote:
> Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>

There has been a misunderstanding.  I never sent a Reviewed-by
line for this patch.

-- 
Eduardo

Re: [Qemu-devel] [PATCH V5 3/4] target-i386: add rtc 0x70 port as coalesced_pio

[Eduardo Habkost]

On Thu, Aug 30, 2018 at 11:50:15PM +0800, Peng Hao wrote:
> Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>

There has been a misunderstanding.  I never sent a Reviewed-by
line for this patch.

-- 
Eduardo

Re: [PATCH V5 4/4] target-i386: add i440fx 0xcf8 port as coalesced_pio

[Eduardo Habkost]

On Thu, Aug 30, 2018 at 11:50:16PM +0800, Peng Hao wrote:
> Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>

There has been a misunderstanding.  I never sent a Reviewed-by
line for this patch.

-- 
Eduardo

Re: [Qemu-devel] [PATCH V5 4/4] target-i386: add i440fx 0xcf8 port as coalesced_pio

[Eduardo Habkost]

On Thu, Aug 30, 2018 at 11:50:16PM +0800, Peng Hao wrote:
> Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>

There has been a misunderstanding.  I never sent a Reviewed-by
line for this patch.

-- 
Eduardo

Re: [PATCH V5 1/4] target-i386: introduce coalesced_pio kvm header update

[Michael S. Tsirkin]

On Fri, Aug 31, 2018 at 05:05:02PM +0800, Peng Hao wrote:
> add coalesced_pio's struct and KVM_CAP_COALESCED_PIO header.
> 
> Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>

I can merge ths together with q35 patch, but pls
get acks from kvm folks, to this end fix up
commit logs and subjects to match reality and repost.

> ---
>  accel/kvm/kvm-all.c       |  4 ++--
>  linux-headers/linux/kvm.h | 11 +++++++++--
>  2 files changed, 11 insertions(+), 4 deletions(-)
> 
> diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
> index eb7db92..4a3909d 100644
> --- a/accel/kvm/kvm-all.c
> +++ b/accel/kvm/kvm-all.c
> @@ -536,7 +536,7 @@ static void kvm_coalesce_mmio_region(MemoryListener *listener,
>  
>          zone.addr = start;
>          zone.size = size;
> -        zone.pad = 0;
> +        zone.pio = 0;
>  
>          (void)kvm_vm_ioctl(s, KVM_REGISTER_COALESCED_MMIO, &zone);
>      }
> @@ -553,7 +553,7 @@ static void kvm_uncoalesce_mmio_region(MemoryListener *listener,
>  
>          zone.addr = start;
>          zone.size = size;
> -        zone.pad = 0;
> +        zone.pio = 0;
>  
>          (void)kvm_vm_ioctl(s, KVM_UNREGISTER_COALESCED_MMIO, &zone);
>      }
> diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h
> index 98f389a..1cb0d41 100644
> --- a/linux-headers/linux/kvm.h
> +++ b/linux-headers/linux/kvm.h
> @@ -420,13 +420,19 @@ struct kvm_run {
>  struct kvm_coalesced_mmio_zone {
>  	__u64 addr;
>  	__u32 size;
> -	__u32 pad;
> +	union {
> +		__u32 pad;
> +		__u32 pio;
> +	};
>  };
>  
>  struct kvm_coalesced_mmio {
>  	__u64 phys_addr;
>  	__u32 len;
> -	__u32 pad;
> +	union {
> +		__u32 pad;
> +		__u32 pio;
> +	};
>  	__u8  data[8];
>  };
>  
> @@ -949,6 +955,7 @@ struct kvm_ppc_resize_hpt {
>  #define KVM_CAP_GET_MSR_FEATURES 153
>  #define KVM_CAP_HYPERV_EVENTFD 154
>  #define KVM_CAP_HYPERV_TLBFLUSH 155
> +#define KVM_CAP_COALESCED_PIO 156
>  
>  #ifdef KVM_CAP_IRQ_ROUTING
>  
> -- 
> 1.8.3.1

On Fri, Aug 31, 2018 at 05:05:03PM +0800, Peng Hao wrote:
> Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
> ---
>  accel/kvm/kvm-all.c   | 57 +++++++++++++++++++++++++++++++++++++++++++++++----
>  include/exec/memory.h |  4 ++--
>  memory.c              |  4 ++--
>  3 files changed, 57 insertions(+), 8 deletions(-)
> 
> diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
> index 4a3909d..11d8d78 100644
> --- a/accel/kvm/kvm-all.c
> +++ b/accel/kvm/kvm-all.c
> @@ -78,6 +78,7 @@ struct KVMState
>      int fd;
>      int vmfd;
>      int coalesced_mmio;
> +    int coalesced_pio;
>      struct kvm_coalesced_mmio_ring *coalesced_mmio_ring;
>      bool coalesced_flush_in_progress;
>      int vcpu_events;
> @@ -559,6 +560,45 @@ static void kvm_uncoalesce_mmio_region(MemoryListener *listener,
>      }
>  }
>  
> +static void kvm_coalesce_pio_add(MemoryListener *listener,
> +                                MemoryRegionSection *section,
> +                                hwaddr start, hwaddr size)
> +{
> +    KVMState *s = kvm_state;
> +
> +    if (s->coalesced_pio) {
> +        struct kvm_coalesced_mmio_zone zone;
> +
> +        zone.addr = start;
> +        zone.size = size;
> +        zone.pio = 1;
> +
> +        (void)kvm_vm_ioctl(s, KVM_REGISTER_COALESCED_MMIO, &zone);
> +    }
> +}
> +
> +static void kvm_coalesce_pio_del(MemoryListener *listener,
> +                                MemoryRegionSection *section,
> +                                hwaddr start, hwaddr size)
> +{
> +    KVMState *s = kvm_state;
> +
> +    if (s->coalesced_pio) {
> +        struct kvm_coalesced_mmio_zone zone;
> +
> +        zone.addr = start;
> +        zone.size = size;
> +        zone.pio = 1;
> +
> +        (void)kvm_vm_ioctl(s, KVM_UNREGISTER_COALESCED_MMIO, &zone);
> +     }
> +}
> +
> +static MemoryListener kvm_coalesced_pio_listener = {
> +    .coalesced_io_add = kvm_coalesce_pio_add,
> +    .coalesced_io_del = kvm_coalesce_pio_del,
> +};
> +
>  int kvm_check_extension(KVMState *s, unsigned int extension)
>  {
>      int ret;
> @@ -1615,6 +1655,8 @@ static int kvm_init(MachineState *ms)
>      }
>  
>      s->coalesced_mmio = kvm_check_extension(s, KVM_CAP_COALESCED_MMIO);
> +    s->coalesced_pio = s->coalesced_mmio &&
> +                       kvm_check_extension(s, KVM_CAP_COALESCED_PIO);
>  
>  #ifdef KVM_CAP_VCPU_EVENTS
>      s->vcpu_events = kvm_check_extension(s, KVM_CAP_VCPU_EVENTS);
> @@ -1687,13 +1729,15 @@ static int kvm_init(MachineState *ms)
>          s->memory_listener.listener.eventfd_add = kvm_mem_ioeventfd_add;
>          s->memory_listener.listener.eventfd_del = kvm_mem_ioeventfd_del;
>      }
> -    s->memory_listener.listener.coalesced_mmio_add = kvm_coalesce_mmio_region;
> -    s->memory_listener.listener.coalesced_mmio_del = kvm_uncoalesce_mmio_region;
> +    s->memory_listener.listener.coalesced_io_add = kvm_coalesce_mmio_region;
> +    s->memory_listener.listener.coalesced_io_del = kvm_uncoalesce_mmio_region;
>  
>      kvm_memory_listener_register(s, &s->memory_listener,
>                                   &address_space_memory, 0);
>      memory_listener_register(&kvm_io_listener,
>                               &address_space_io);
> +    memory_listener_register(&kvm_coalesced_pio_listener,
> +                             &address_space_io);
>  
>      s->many_ioeventfds = kvm_check_many_ioeventfds();
>  
> @@ -1775,8 +1819,13 @@ void kvm_flush_coalesced_mmio_buffer(void)
>              struct kvm_coalesced_mmio *ent;
>  
>              ent = &ring->coalesced_mmio[ring->first];
> -
> -            cpu_physical_memory_write(ent->phys_addr, ent->data, ent->len);
> +            if (ent->pio == 1) {
> +                address_space_rw(&address_space_io, ent->phys_addr,
> +                                 MEMTXATTRS_UNSPECIFIED, ent->data,
> +                                 ent->len, true);
> +            } else {
> +                cpu_physical_memory_write(ent->phys_addr, ent->data, ent->len);
> +            }
>              smp_wmb();
>              ring->first = (ring->first + 1) % KVM_COALESCED_MMIO_MAX;
>          }
> diff --git a/include/exec/memory.h b/include/exec/memory.h
> index 448d41a..4600fa3 100644
> --- a/include/exec/memory.h
> +++ b/include/exec/memory.h
> @@ -410,9 +410,9 @@ struct MemoryListener {
>                          bool match_data, uint64_t data, EventNotifier *e);
>      void (*eventfd_del)(MemoryListener *listener, MemoryRegionSection *section,
>                          bool match_data, uint64_t data, EventNotifier *e);
> -    void (*coalesced_mmio_add)(MemoryListener *listener, MemoryRegionSection *section,
> +    void (*coalesced_io_add)(MemoryListener *listener, MemoryRegionSection *section,
>                                 hwaddr addr, hwaddr len);
> -    void (*coalesced_mmio_del)(MemoryListener *listener, MemoryRegionSection *section,
> +    void (*coalesced_io_del)(MemoryListener *listener, MemoryRegionSection *section,
>                                 hwaddr addr, hwaddr len);
>      /* Lower = earlier (during add), later (during del) */
>      unsigned priority;
> diff --git a/memory.c b/memory.c
> index e9cd446..8b0311e 100644
> --- a/memory.c
> +++ b/memory.c
> @@ -2126,7 +2126,7 @@ static void memory_region_update_coalesced_range_as(MemoryRegion *mr, AddressSpa
>                  .size = fr->addr.size,
>              };
>  
> -            MEMORY_LISTENER_CALL(as, coalesced_mmio_del, Reverse, &section,
> +            MEMORY_LISTENER_CALL(as, coalesced_io_del, Reverse, &section,
>                                   int128_get64(fr->addr.start),
>                                   int128_get64(fr->addr.size));
>              QTAILQ_FOREACH(cmr, &mr->coalesced, link) {
> @@ -2137,7 +2137,7 @@ static void memory_region_update_coalesced_range_as(MemoryRegion *mr, AddressSpa
>                      continue;
>                  }
>                  tmp = addrrange_intersection(tmp, fr->addr);
> -                MEMORY_LISTENER_CALL(as, coalesced_mmio_add, Forward, &section,
> +                MEMORY_LISTENER_CALL(as, coalesced_io_add, Forward, &section,
>                                       int128_get64(tmp.start),
>                                       int128_get64(tmp.size));
>              }
> -- 
> 1.8.3.1

On Fri, Aug 31, 2018 at 05:05:04PM +0800, Peng Hao wrote:
> Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
> ---
>  hw/timer/mc146818rtc.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/hw/timer/mc146818rtc.c b/hw/timer/mc146818rtc.c
> index 6f1f723..b19ef51 100644
> --- a/hw/timer/mc146818rtc.c
> +++ b/hw/timer/mc146818rtc.c
> @@ -70,6 +70,7 @@ typedef struct RTCState {
>      ISADevice parent_obj;
>  
>      MemoryRegion io;
> +    MemoryRegion coalesced_io;
>      uint8_t cmos_data[128];
>      uint8_t cmos_index;
>      int32_t base_year;
> @@ -990,6 +991,13 @@ static void rtc_realizefn(DeviceState *dev, Error **errp)
>      memory_region_init_io(&s->io, OBJECT(s), &cmos_ops, s, "rtc", 2);
>      isa_register_ioport(isadev, &s->io, base);
>  
> +    /* register rtc 0x70 port as coalesced_pio */
> +    memory_region_set_flush_coalesced(&s->io);
> +    memory_region_init_io(&s->coalesced_io, OBJECT(s), &cmos_ops,
> +                          s, "rtc1", 1);
> +    isa_register_ioport(isadev, &s->coalesced_io, base);
> +    memory_region_add_coalescing(&s->coalesced_io, 0, 1);
> +
>      qdev_set_legacy_instance_id(dev, base, 3);
>      qemu_register_reset(rtc_reset, s);
>  
> -- 
> 1.8.3.1

On Fri, Aug 31, 2018 at 05:05:05PM +0800, Peng Hao wrote:
> Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
> ---
>  hw/pci-host/piix.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c
> index 0e60834..da73743 100644
> --- a/hw/pci-host/piix.c
> +++ b/hw/pci-host/piix.c
> @@ -327,6 +327,10 @@ static void i440fx_pcihost_realize(DeviceState *dev, Error **errp)
>  
>      sysbus_add_io(sbd, 0xcfc, &s->data_mem);
>      sysbus_init_ioports(sbd, 0xcfc, 4);
> +
> +    /* register i440fx 0xcf8 port as coalesced pio */
> +    memory_region_set_flush_coalesced(&s->data_mem);
> +    memory_region_add_coalescing(&s->conf_mem, 0, 4);
>  }
>  
>  static void i440fx_realize(PCIDevice *dev, Error **errp)
> -- 
> 1.8.3.1

Re: [PATCH V5 1/4] target-i386: introduce coalesced_pio kvm header update

[Michael S. Tsirkin]

On Fri, Aug 31, 2018 at 05:05:02PM +0800, Peng Hao wrote:
> add coalesced_pio's struct and KVM_CAP_COALESCED_PIO header.
> 
> Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>

Despite what the subject says, this is a kvm patch
not a target-i386 one. In fact none of these are.

And it does not add a header.

Please change subjects so correct people review your patches.
E.g. this one should be

kvm: add coalesced_pio support

Needs to be rebased too.

-- 
MST

[PATCH V5 1/4] target-i386: introduce coalesced_pio kvm header update

[Peng Hao]

add coalesced_pio's struct and KVM_CAP_COALESCED_PIO header.

Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
---
 accel/kvm/kvm-all.c       |  4 ++--
 linux-headers/linux/kvm.h | 11 +++++++++--
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index eb7db92..4a3909d 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -536,7 +536,7 @@ static void kvm_coalesce_mmio_region(MemoryListener *listener,
 
         zone.addr = start;
         zone.size = size;
-        zone.pad = 0;
+        zone.pio = 0;
 
         (void)kvm_vm_ioctl(s, KVM_REGISTER_COALESCED_MMIO, &zone);
     }
@@ -553,7 +553,7 @@ static void kvm_uncoalesce_mmio_region(MemoryListener *listener,
 
         zone.addr = start;
         zone.size = size;
-        zone.pad = 0;
+        zone.pio = 0;
 
         (void)kvm_vm_ioctl(s, KVM_UNREGISTER_COALESCED_MMIO, &zone);
     }
diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h
index 98f389a..1cb0d41 100644
--- a/linux-headers/linux/kvm.h
+++ b/linux-headers/linux/kvm.h
@@ -420,13 +420,19 @@ struct kvm_run {
 struct kvm_coalesced_mmio_zone {
 	__u64 addr;
 	__u32 size;
-	__u32 pad;
+	union {
+		__u32 pad;
+		__u32 pio;
+	};
 };
 
 struct kvm_coalesced_mmio {
 	__u64 phys_addr;
 	__u32 len;
-	__u32 pad;
+	union {
+		__u32 pad;
+		__u32 pio;
+	};
 	__u8  data[8];
 };
 
@@ -949,6 +955,7 @@ struct kvm_ppc_resize_hpt {
 #define KVM_CAP_GET_MSR_FEATURES 153
 #define KVM_CAP_HYPERV_EVENTFD 154
 #define KVM_CAP_HYPERV_TLBFLUSH 155
+#define KVM_CAP_COALESCED_PIO 156
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
-- 
1.8.3.1