[PATCH v2 17/21] virtio-net: Use virtual time for RSC timers

Alex Bennée posted 21 patches 3 months, 1 week ago
[PATCH v2 17/21] virtio-net: Use virtual time for RSC timers
Posted by Alex Bennée 3 months, 1 week ago
From: Nicholas Piggin <npiggin@gmail.com>

Receive coalescing is visible to the target machine, so its timers
should use virtual time like other timers in virtio-net, to be
compatible with record-replay.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20240813050638.446172-10-npiggin@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
---
 hw/net/virtio-net.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index 10ebaae5e2..ed33a32877 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -2124,7 +2124,7 @@ static void virtio_net_rsc_purge(void *opq)
     chain->stat.timer++;
     if (!QTAILQ_EMPTY(&chain->buffers)) {
         timer_mod(chain->drain_timer,
-              qemu_clock_get_ns(QEMU_CLOCK_HOST) + chain->n->rsc_timeout);
+              qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + chain->n->rsc_timeout);
     }
 }
 
@@ -2360,7 +2360,7 @@ static size_t virtio_net_rsc_do_coalesce(VirtioNetRscChain *chain,
         chain->stat.empty_cache++;
         virtio_net_rsc_cache_buf(chain, nc, buf, size);
         timer_mod(chain->drain_timer,
-              qemu_clock_get_ns(QEMU_CLOCK_HOST) + chain->n->rsc_timeout);
+              qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + chain->n->rsc_timeout);
         return size;
     }
 
@@ -2598,7 +2598,7 @@ static VirtioNetRscChain *virtio_net_rsc_lookup_chain(VirtIONet *n,
         chain->max_payload = VIRTIO_NET_MAX_IP6_PAYLOAD;
         chain->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
     }
-    chain->drain_timer = timer_new_ns(QEMU_CLOCK_HOST,
+    chain->drain_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
                                       virtio_net_rsc_purge, chain);
     memset(&chain->stat, 0, sizeof(chain->stat));
 
-- 
2.39.2


Re: [PATCH v2 17/21] virtio-net: Use virtual time for RSC timers
Posted by Michael S. Tsirkin 3 months, 1 week ago
On Tue, Aug 13, 2024 at 09:23:25PM +0100, Alex Bennée wrote:
> From: Nicholas Piggin <npiggin@gmail.com>
> 
> Receive coalescing is visible to the target machine, so its timers
> should use virtual time like other timers in virtio-net, to be
> compatible with record-replay.
> 
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> Message-Id: <20240813050638.446172-10-npiggin@gmail.com>
> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

Acked-by: Michael S. Tsirkin <mst@redhat.com>

> ---
>  hw/net/virtio-net.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
> index 10ebaae5e2..ed33a32877 100644
> --- a/hw/net/virtio-net.c
> +++ b/hw/net/virtio-net.c
> @@ -2124,7 +2124,7 @@ static void virtio_net_rsc_purge(void *opq)
>      chain->stat.timer++;
>      if (!QTAILQ_EMPTY(&chain->buffers)) {
>          timer_mod(chain->drain_timer,
> -              qemu_clock_get_ns(QEMU_CLOCK_HOST) + chain->n->rsc_timeout);
> +              qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + chain->n->rsc_timeout);
>      }
>  }
>  
> @@ -2360,7 +2360,7 @@ static size_t virtio_net_rsc_do_coalesce(VirtioNetRscChain *chain,
>          chain->stat.empty_cache++;
>          virtio_net_rsc_cache_buf(chain, nc, buf, size);
>          timer_mod(chain->drain_timer,
> -              qemu_clock_get_ns(QEMU_CLOCK_HOST) + chain->n->rsc_timeout);
> +              qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + chain->n->rsc_timeout);
>          return size;
>      }
>  
> @@ -2598,7 +2598,7 @@ static VirtioNetRscChain *virtio_net_rsc_lookup_chain(VirtIONet *n,
>          chain->max_payload = VIRTIO_NET_MAX_IP6_PAYLOAD;
>          chain->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
>      }
> -    chain->drain_timer = timer_new_ns(QEMU_CLOCK_HOST,
> +    chain->drain_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
>                                        virtio_net_rsc_purge, chain);
>      memset(&chain->stat, 0, sizeof(chain->stat));
>  
> -- 
> 2.39.2