forked from rpms/qemu-kvm
parent
506ebbc1a6
commit
85f6a2f140
@ -0,0 +1,155 @@
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From 6319eaee8c2206c4eca858a11ed7c9b7a2f3dff9 Mon Sep 17 00:00:00 2001
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From: Marcelo Tosatti <mtosatti@redhat.com>
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Date: Thu, 29 Jun 2023 15:13:57 -0300
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Subject: [PATCH] kvm: reuse per-vcpu stats fd to avoid vcpu interruption
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RH-Author: Marcelo Tosatti <None>
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RH-MergeRequest: 290: kvm: reuse per-vcpu stats fd to avoid vcpu interruption
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RH-Bugzilla: 2221219
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RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
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RH-Commit: [1/1] cf6c3188e26c6eae99b48db1f75837e11d1e4489
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Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2214884
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Commit: 3b6f485275ae95a81eec589d2773b86ca9ddec4d
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A regression has been detected in latency testing of KVM guests.
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More specifically, it was observed that the cyclictest
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numbers inside of an isolated vcpu (running on isolated pcpu) are:
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Where a maximum of 50us is acceptable.
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The implementation of KVM_GET_STATS_FD uses run_on_cpu to query
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per vcpu statistics, which interrupts the vcpu (and is unnecessary).
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To fix this, open the per vcpu stats fd on vcpu initialization,
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and read from that fd from QEMU's main thread.
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Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
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Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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---
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accel/kvm/kvm-all.c | 30 +++++++++++++++---------------
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include/hw/core/cpu.h | 1 +
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2 files changed, 16 insertions(+), 15 deletions(-)
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diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
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index 39ed30ab59..c86a6798c6 100644
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--- a/accel/kvm/kvm-all.c
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+++ b/accel/kvm/kvm-all.c
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@@ -450,6 +450,8 @@ int kvm_init_vcpu(CPUState *cpu, Error **errp)
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"kvm_init_vcpu: kvm_arch_init_vcpu failed (%lu)",
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kvm_arch_vcpu_id(cpu));
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}
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+ cpu->kvm_vcpu_stats_fd = kvm_vcpu_ioctl(cpu, KVM_GET_STATS_FD, NULL);
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+
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err:
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return ret;
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}
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@@ -3950,7 +3952,7 @@ static StatsDescriptors *find_stats_descriptors(StatsTarget target, int stats_fd
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/* Read stats header */
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kvm_stats_header = &descriptors->kvm_stats_header;
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- ret = read(stats_fd, kvm_stats_header, sizeof(*kvm_stats_header));
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+ ret = pread(stats_fd, kvm_stats_header, sizeof(*kvm_stats_header), 0);
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if (ret != sizeof(*kvm_stats_header)) {
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error_setg(errp, "KVM stats: failed to read stats header: "
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"expected %zu actual %zu",
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@@ -3981,7 +3983,8 @@ static StatsDescriptors *find_stats_descriptors(StatsTarget target, int stats_fd
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}
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static void query_stats(StatsResultList **result, StatsTarget target,
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- strList *names, int stats_fd, Error **errp)
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+ strList *names, int stats_fd, CPUState *cpu,
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+ Error **errp)
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{
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struct kvm_stats_desc *kvm_stats_desc;
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struct kvm_stats_header *kvm_stats_header;
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@@ -4039,7 +4042,7 @@ static void query_stats(StatsResultList **result, StatsTarget target,
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break;
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case STATS_TARGET_VCPU:
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add_stats_entry(result, STATS_PROVIDER_KVM,
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- current_cpu->parent_obj.canonical_path,
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+ cpu->parent_obj.canonical_path,
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stats_list);
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break;
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default:
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@@ -4076,10 +4079,9 @@ static void query_stats_schema(StatsSchemaList **result, StatsTarget target,
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add_stats_schema(result, STATS_PROVIDER_KVM, target, stats_list);
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}
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-static void query_stats_vcpu(CPUState *cpu, run_on_cpu_data data)
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+static void query_stats_vcpu(CPUState *cpu, StatsArgs *kvm_stats_args)
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{
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- StatsArgs *kvm_stats_args = (StatsArgs *) data.host_ptr;
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- int stats_fd = kvm_vcpu_ioctl(cpu, KVM_GET_STATS_FD, NULL);
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+ int stats_fd = cpu->kvm_vcpu_stats_fd;
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Error *local_err = NULL;
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if (stats_fd == -1) {
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@@ -4088,14 +4090,13 @@ static void query_stats_vcpu(CPUState *cpu, run_on_cpu_data data)
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return;
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}
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query_stats(kvm_stats_args->result.stats, STATS_TARGET_VCPU,
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- kvm_stats_args->names, stats_fd, kvm_stats_args->errp);
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- close(stats_fd);
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+ kvm_stats_args->names, stats_fd, cpu,
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+ kvm_stats_args->errp);
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}
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-static void query_stats_schema_vcpu(CPUState *cpu, run_on_cpu_data data)
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+static void query_stats_schema_vcpu(CPUState *cpu, StatsArgs *kvm_stats_args)
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{
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- StatsArgs *kvm_stats_args = (StatsArgs *) data.host_ptr;
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- int stats_fd = kvm_vcpu_ioctl(cpu, KVM_GET_STATS_FD, NULL);
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+ int stats_fd = cpu->kvm_vcpu_stats_fd;
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Error *local_err = NULL;
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if (stats_fd == -1) {
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@@ -4105,7 +4106,6 @@ static void query_stats_schema_vcpu(CPUState *cpu, run_on_cpu_data data)
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}
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query_stats_schema(kvm_stats_args->result.schema, STATS_TARGET_VCPU, stats_fd,
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kvm_stats_args->errp);
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- close(stats_fd);
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}
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static void query_stats_cb(StatsResultList **result, StatsTarget target,
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@@ -4123,7 +4123,7 @@ static void query_stats_cb(StatsResultList **result, StatsTarget target,
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error_setg_errno(errp, errno, "KVM stats: ioctl failed");
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return;
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}
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- query_stats(result, target, names, stats_fd, errp);
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+ query_stats(result, target, names, stats_fd, NULL, errp);
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close(stats_fd);
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break;
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}
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@@ -4137,7 +4137,7 @@ static void query_stats_cb(StatsResultList **result, StatsTarget target,
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if (!apply_str_list_filter(cpu->parent_obj.canonical_path, targets)) {
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continue;
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}
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- run_on_cpu(cpu, query_stats_vcpu, RUN_ON_CPU_HOST_PTR(&stats_args));
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+ query_stats_vcpu(cpu, &stats_args);
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}
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break;
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}
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@@ -4163,6 +4163,6 @@ void query_stats_schemas_cb(StatsSchemaList **result, Error **errp)
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if (first_cpu) {
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stats_args.result.schema = result;
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stats_args.errp = errp;
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- run_on_cpu(first_cpu, query_stats_schema_vcpu, RUN_ON_CPU_HOST_PTR(&stats_args));
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+ query_stats_schema_vcpu(first_cpu, &stats_args);
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}
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}
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diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h
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index 2417597236..362f22ca06 100644
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--- a/include/hw/core/cpu.h
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+++ b/include/hw/core/cpu.h
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@@ -397,6 +397,7 @@ struct CPUState {
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struct kvm_dirty_gfn *kvm_dirty_gfns;
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uint32_t kvm_fetch_index;
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uint64_t dirty_pages;
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+ int kvm_vcpu_stats_fd;
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/* Use by accel-block: CPU is executing an ioctl() */
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QemuLockCnt in_ioctl_lock;
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--
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2.39.3
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@ -0,0 +1,84 @@
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From 757767330abb2c0a650c387a9a5965fee224beee Mon Sep 17 00:00:00 2001
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From: =?UTF-8?q?Eugenio=20P=C3=A9rez?= <eperezma@redhat.com>
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Date: Thu, 9 Feb 2023 18:00:04 +0100
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Subject: [PATCH] vdpa: stop all svq on device deletion
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MIME-Version: 1.0
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Content-Type: text/plain; charset=UTF-8
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Content-Transfer-Encoding: 8bit
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RH-Author: Laurent Vivier <lvivier@redhat.com>
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RH-MergeRequest: 286: vdpa: stop all svq on device deletion
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RH-Bugzilla: 2213864
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RH-Acked-by: Cindy Lu <lulu@redhat.com>
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RH-Acked-by: Eugenio Pérez <eperezma@redhat.com>
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RH-Acked-by: Stefano Garzarella <sgarzare@redhat.com>
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RH-Commit: [1/1] b9ff402e4c6e386be3ea867df9358cdaa283cda7
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Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2213864
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Upstream-Status: merged
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Not stopping them leave the device in a bad state when virtio-net
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fronted device is unplugged with device_del monitor command.
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This is not triggable in regular poweroff or qemu forces shutdown
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because cleanup is called right after vhost_vdpa_dev_start(false). But
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devices hot unplug does not call vdpa device cleanups. This lead to all
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the vhost_vdpa devices without stop the SVQ but the last.
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Fix it and clean the code, making it symmetric with
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vhost_vdpa_svqs_start.
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Fixes: dff4426fa656 ("vhost: Add Shadow VirtQueue kick forwarding capabilities")
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Reported-by: Lei Yang <leiyang@redhat.com>
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Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
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Message-Id: <20230209170004.899472-1-eperezma@redhat.com>
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Tested-by: Laurent Vivier <lvivier@redhat.com>
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Acked-by: Jason Wang <jasowang@redhat.com>
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(cherry picked from commit 2e1a9de96b487cf818a22d681cad8d3f5d18dcca)
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---
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hw/virtio/vhost-vdpa.c | 17 ++---------------
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1 file changed, 2 insertions(+), 15 deletions(-)
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diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
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index 72ff06673c..46896b7592 100644
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--- a/hw/virtio/vhost-vdpa.c
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+++ b/hw/virtio/vhost-vdpa.c
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@@ -669,26 +669,11 @@ static int vhost_vdpa_get_device_id(struct vhost_dev *dev,
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return ret;
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}
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-static void vhost_vdpa_reset_svq(struct vhost_vdpa *v)
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-{
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- if (!v->shadow_vqs_enabled) {
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- return;
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- }
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-
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- for (unsigned i = 0; i < v->shadow_vqs->len; ++i) {
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- VhostShadowVirtqueue *svq = g_ptr_array_index(v->shadow_vqs, i);
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- vhost_svq_stop(svq);
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- }
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-}
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-
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static int vhost_vdpa_reset_device(struct vhost_dev *dev)
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{
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- struct vhost_vdpa *v = dev->opaque;
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int ret;
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uint8_t status = 0;
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- vhost_vdpa_reset_svq(v);
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-
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ret = vhost_vdpa_call(dev, VHOST_VDPA_SET_STATUS, &status);
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trace_vhost_vdpa_reset_device(dev, status);
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return ret;
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@@ -1080,6 +1065,8 @@ static void vhost_vdpa_svqs_stop(struct vhost_dev *dev)
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for (unsigned i = 0; i < v->shadow_vqs->len; ++i) {
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VhostShadowVirtqueue *svq = g_ptr_array_index(v->shadow_vqs, i);
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+
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+ vhost_svq_stop(svq);
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vhost_vdpa_svq_unmap_rings(dev, svq);
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event_notifier_cleanup(&svq->hdev_kick);
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--
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2.39.3
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