parent
fe66ecbf55
commit
5752c9931d
@ -0,0 +1,155 @@
|
||||
From 6319eaee8c2206c4eca858a11ed7c9b7a2f3dff9 Mon Sep 17 00:00:00 2001
|
||||
From: Marcelo Tosatti <mtosatti@redhat.com>
|
||||
Date: Thu, 29 Jun 2023 15:13:57 -0300
|
||||
Subject: [PATCH] kvm: reuse per-vcpu stats fd to avoid vcpu interruption
|
||||
|
||||
RH-Author: Marcelo Tosatti <None>
|
||||
RH-MergeRequest: 290: kvm: reuse per-vcpu stats fd to avoid vcpu interruption
|
||||
RH-Bugzilla: 2221219
|
||||
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
|
||||
RH-Commit: [1/1] cf6c3188e26c6eae99b48db1f75837e11d1e4489
|
||||
|
||||
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2214884
|
||||
Commit: 3b6f485275ae95a81eec589d2773b86ca9ddec4d
|
||||
|
||||
A regression has been detected in latency testing of KVM guests.
|
||||
More specifically, it was observed that the cyclictest
|
||||
numbers inside of an isolated vcpu (running on isolated pcpu) are:
|
||||
|
||||
Where a maximum of 50us is acceptable.
|
||||
|
||||
The implementation of KVM_GET_STATS_FD uses run_on_cpu to query
|
||||
per vcpu statistics, which interrupts the vcpu (and is unnecessary).
|
||||
|
||||
To fix this, open the per vcpu stats fd on vcpu initialization,
|
||||
and read from that fd from QEMU's main thread.
|
||||
|
||||
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
|
||||
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
|
||||
---
|
||||
accel/kvm/kvm-all.c | 30 +++++++++++++++---------------
|
||||
include/hw/core/cpu.h | 1 +
|
||||
2 files changed, 16 insertions(+), 15 deletions(-)
|
||||
|
||||
diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
|
||||
index 39ed30ab59..c86a6798c6 100644
|
||||
--- a/accel/kvm/kvm-all.c
|
||||
+++ b/accel/kvm/kvm-all.c
|
||||
@@ -450,6 +450,8 @@ int kvm_init_vcpu(CPUState *cpu, Error **errp)
|
||||
"kvm_init_vcpu: kvm_arch_init_vcpu failed (%lu)",
|
||||
kvm_arch_vcpu_id(cpu));
|
||||
}
|
||||
+ cpu->kvm_vcpu_stats_fd = kvm_vcpu_ioctl(cpu, KVM_GET_STATS_FD, NULL);
|
||||
+
|
||||
err:
|
||||
return ret;
|
||||
}
|
||||
@@ -3950,7 +3952,7 @@ static StatsDescriptors *find_stats_descriptors(StatsTarget target, int stats_fd
|
||||
|
||||
/* Read stats header */
|
||||
kvm_stats_header = &descriptors->kvm_stats_header;
|
||||
- ret = read(stats_fd, kvm_stats_header, sizeof(*kvm_stats_header));
|
||||
+ ret = pread(stats_fd, kvm_stats_header, sizeof(*kvm_stats_header), 0);
|
||||
if (ret != sizeof(*kvm_stats_header)) {
|
||||
error_setg(errp, "KVM stats: failed to read stats header: "
|
||||
"expected %zu actual %zu",
|
||||
@@ -3981,7 +3983,8 @@ static StatsDescriptors *find_stats_descriptors(StatsTarget target, int stats_fd
|
||||
}
|
||||
|
||||
static void query_stats(StatsResultList **result, StatsTarget target,
|
||||
- strList *names, int stats_fd, Error **errp)
|
||||
+ strList *names, int stats_fd, CPUState *cpu,
|
||||
+ Error **errp)
|
||||
{
|
||||
struct kvm_stats_desc *kvm_stats_desc;
|
||||
struct kvm_stats_header *kvm_stats_header;
|
||||
@@ -4039,7 +4042,7 @@ static void query_stats(StatsResultList **result, StatsTarget target,
|
||||
break;
|
||||
case STATS_TARGET_VCPU:
|
||||
add_stats_entry(result, STATS_PROVIDER_KVM,
|
||||
- current_cpu->parent_obj.canonical_path,
|
||||
+ cpu->parent_obj.canonical_path,
|
||||
stats_list);
|
||||
break;
|
||||
default:
|
||||
@@ -4076,10 +4079,9 @@ static void query_stats_schema(StatsSchemaList **result, StatsTarget target,
|
||||
add_stats_schema(result, STATS_PROVIDER_KVM, target, stats_list);
|
||||
}
|
||||
|
||||
-static void query_stats_vcpu(CPUState *cpu, run_on_cpu_data data)
|
||||
+static void query_stats_vcpu(CPUState *cpu, StatsArgs *kvm_stats_args)
|
||||
{
|
||||
- StatsArgs *kvm_stats_args = (StatsArgs *) data.host_ptr;
|
||||
- int stats_fd = kvm_vcpu_ioctl(cpu, KVM_GET_STATS_FD, NULL);
|
||||
+ int stats_fd = cpu->kvm_vcpu_stats_fd;
|
||||
Error *local_err = NULL;
|
||||
|
||||
if (stats_fd == -1) {
|
||||
@@ -4088,14 +4090,13 @@ static void query_stats_vcpu(CPUState *cpu, run_on_cpu_data data)
|
||||
return;
|
||||
}
|
||||
query_stats(kvm_stats_args->result.stats, STATS_TARGET_VCPU,
|
||||
- kvm_stats_args->names, stats_fd, kvm_stats_args->errp);
|
||||
- close(stats_fd);
|
||||
+ kvm_stats_args->names, stats_fd, cpu,
|
||||
+ kvm_stats_args->errp);
|
||||
}
|
||||
|
||||
-static void query_stats_schema_vcpu(CPUState *cpu, run_on_cpu_data data)
|
||||
+static void query_stats_schema_vcpu(CPUState *cpu, StatsArgs *kvm_stats_args)
|
||||
{
|
||||
- StatsArgs *kvm_stats_args = (StatsArgs *) data.host_ptr;
|
||||
- int stats_fd = kvm_vcpu_ioctl(cpu, KVM_GET_STATS_FD, NULL);
|
||||
+ int stats_fd = cpu->kvm_vcpu_stats_fd;
|
||||
Error *local_err = NULL;
|
||||
|
||||
if (stats_fd == -1) {
|
||||
@@ -4105,7 +4106,6 @@ static void query_stats_schema_vcpu(CPUState *cpu, run_on_cpu_data data)
|
||||
}
|
||||
query_stats_schema(kvm_stats_args->result.schema, STATS_TARGET_VCPU, stats_fd,
|
||||
kvm_stats_args->errp);
|
||||
- close(stats_fd);
|
||||
}
|
||||
|
||||
static void query_stats_cb(StatsResultList **result, StatsTarget target,
|
||||
@@ -4123,7 +4123,7 @@ static void query_stats_cb(StatsResultList **result, StatsTarget target,
|
||||
error_setg_errno(errp, errno, "KVM stats: ioctl failed");
|
||||
return;
|
||||
}
|
||||
- query_stats(result, target, names, stats_fd, errp);
|
||||
+ query_stats(result, target, names, stats_fd, NULL, errp);
|
||||
close(stats_fd);
|
||||
break;
|
||||
}
|
||||
@@ -4137,7 +4137,7 @@ static void query_stats_cb(StatsResultList **result, StatsTarget target,
|
||||
if (!apply_str_list_filter(cpu->parent_obj.canonical_path, targets)) {
|
||||
continue;
|
||||
}
|
||||
- run_on_cpu(cpu, query_stats_vcpu, RUN_ON_CPU_HOST_PTR(&stats_args));
|
||||
+ query_stats_vcpu(cpu, &stats_args);
|
||||
}
|
||||
break;
|
||||
}
|
||||
@@ -4163,6 +4163,6 @@ void query_stats_schemas_cb(StatsSchemaList **result, Error **errp)
|
||||
if (first_cpu) {
|
||||
stats_args.result.schema = result;
|
||||
stats_args.errp = errp;
|
||||
- run_on_cpu(first_cpu, query_stats_schema_vcpu, RUN_ON_CPU_HOST_PTR(&stats_args));
|
||||
+ query_stats_schema_vcpu(first_cpu, &stats_args);
|
||||
}
|
||||
}
|
||||
diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h
|
||||
index 2417597236..362f22ca06 100644
|
||||
--- a/include/hw/core/cpu.h
|
||||
+++ b/include/hw/core/cpu.h
|
||||
@@ -397,6 +397,7 @@ struct CPUState {
|
||||
struct kvm_dirty_gfn *kvm_dirty_gfns;
|
||||
uint32_t kvm_fetch_index;
|
||||
uint64_t dirty_pages;
|
||||
+ int kvm_vcpu_stats_fd;
|
||||
|
||||
/* Use by accel-block: CPU is executing an ioctl() */
|
||||
QemuLockCnt in_ioctl_lock;
|
||||
--
|
||||
2.39.3
|
||||
|
@ -0,0 +1,84 @@
|
||||
From 757767330abb2c0a650c387a9a5965fee224beee Mon Sep 17 00:00:00 2001
|
||||
From: =?UTF-8?q?Eugenio=20P=C3=A9rez?= <eperezma@redhat.com>
|
||||
Date: Thu, 9 Feb 2023 18:00:04 +0100
|
||||
Subject: [PATCH] vdpa: stop all svq on device deletion
|
||||
MIME-Version: 1.0
|
||||
Content-Type: text/plain; charset=UTF-8
|
||||
Content-Transfer-Encoding: 8bit
|
||||
|
||||
RH-Author: Laurent Vivier <lvivier@redhat.com>
|
||||
RH-MergeRequest: 286: vdpa: stop all svq on device deletion
|
||||
RH-Bugzilla: 2213864
|
||||
RH-Acked-by: Cindy Lu <lulu@redhat.com>
|
||||
RH-Acked-by: Eugenio Pérez <eperezma@redhat.com>
|
||||
RH-Acked-by: Stefano Garzarella <sgarzare@redhat.com>
|
||||
RH-Commit: [1/1] b9ff402e4c6e386be3ea867df9358cdaa283cda7
|
||||
|
||||
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2213864
|
||||
Upstream-Status: merged
|
||||
|
||||
Not stopping them leave the device in a bad state when virtio-net
|
||||
fronted device is unplugged with device_del monitor command.
|
||||
|
||||
This is not triggable in regular poweroff or qemu forces shutdown
|
||||
because cleanup is called right after vhost_vdpa_dev_start(false). But
|
||||
devices hot unplug does not call vdpa device cleanups. This lead to all
|
||||
the vhost_vdpa devices without stop the SVQ but the last.
|
||||
|
||||
Fix it and clean the code, making it symmetric with
|
||||
vhost_vdpa_svqs_start.
|
||||
|
||||
Fixes: dff4426fa656 ("vhost: Add Shadow VirtQueue kick forwarding capabilities")
|
||||
Reported-by: Lei Yang <leiyang@redhat.com>
|
||||
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
|
||||
Message-Id: <20230209170004.899472-1-eperezma@redhat.com>
|
||||
Tested-by: Laurent Vivier <lvivier@redhat.com>
|
||||
Acked-by: Jason Wang <jasowang@redhat.com>
|
||||
(cherry picked from commit 2e1a9de96b487cf818a22d681cad8d3f5d18dcca)
|
||||
---
|
||||
hw/virtio/vhost-vdpa.c | 17 ++---------------
|
||||
1 file changed, 2 insertions(+), 15 deletions(-)
|
||||
|
||||
diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
|
||||
index 72ff06673c..46896b7592 100644
|
||||
--- a/hw/virtio/vhost-vdpa.c
|
||||
+++ b/hw/virtio/vhost-vdpa.c
|
||||
@@ -669,26 +669,11 @@ static int vhost_vdpa_get_device_id(struct vhost_dev *dev,
|
||||
return ret;
|
||||
}
|
||||
|
||||
-static void vhost_vdpa_reset_svq(struct vhost_vdpa *v)
|
||||
-{
|
||||
- if (!v->shadow_vqs_enabled) {
|
||||
- return;
|
||||
- }
|
||||
-
|
||||
- for (unsigned i = 0; i < v->shadow_vqs->len; ++i) {
|
||||
- VhostShadowVirtqueue *svq = g_ptr_array_index(v->shadow_vqs, i);
|
||||
- vhost_svq_stop(svq);
|
||||
- }
|
||||
-}
|
||||
-
|
||||
static int vhost_vdpa_reset_device(struct vhost_dev *dev)
|
||||
{
|
||||
- struct vhost_vdpa *v = dev->opaque;
|
||||
int ret;
|
||||
uint8_t status = 0;
|
||||
|
||||
- vhost_vdpa_reset_svq(v);
|
||||
-
|
||||
ret = vhost_vdpa_call(dev, VHOST_VDPA_SET_STATUS, &status);
|
||||
trace_vhost_vdpa_reset_device(dev, status);
|
||||
return ret;
|
||||
@@ -1080,6 +1065,8 @@ static void vhost_vdpa_svqs_stop(struct vhost_dev *dev)
|
||||
|
||||
for (unsigned i = 0; i < v->shadow_vqs->len; ++i) {
|
||||
VhostShadowVirtqueue *svq = g_ptr_array_index(v->shadow_vqs, i);
|
||||
+
|
||||
+ vhost_svq_stop(svq);
|
||||
vhost_vdpa_svq_unmap_rings(dev, svq);
|
||||
|
||||
event_notifier_cleanup(&svq->hdev_kick);
|
||||
--
|
||||
2.39.3
|
||||
|
Loading…
Reference in new issue