diff mbox series

xen-netback: use default TX queue size for vifs

Message ID 20231005140831.89117-1-roger.pau@citrix.com (mailing list archive)
State Accepted
Commit 66cf7435a26917c0c4d6245ad9137e7606e84fdf
Delegated to: Netdev Maintainers
Headers show
Series xen-netback: use default TX queue size for vifs | expand

Checks

Context Check Description
netdev/series_format warning Single patches do not need cover letters; Target tree name not specified in the subject
netdev/tree_selection success Guessed tree name to be net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 9 this patch: 9
netdev/cc_maintainers success CCed 10 of 10 maintainers
netdev/build_clang success Errors and warnings before: 1363 this patch: 1363
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 1363 this patch: 1363
netdev/checkpatch warning WARNING: From:/Signed-off-by: email name mismatch: 'From: Roger Pau Monne <roger.pau@citrix.com>' != 'Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>' WARNING: Please use correct Fixes: style 'Fixes: <12 chars of sha1> ("<title line>")' - ie: 'Fixes: f942dc2552b8 ("xen network backend driver")'
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Roger Pau Monné Oct. 5, 2023, 2:08 p.m. UTC
Do not set netback interfaces (vifs) default TX queue size to the ring size.
The TX queue size is not related to the ring size, and using the ring size (32)
as the queue size can lead to packet drops.  Note the TX side of the vif
interface in the netback domain is the one receiving packets to be injected
to the guest.

Do not explicitly set the TX queue length to any value when creating the
interface, and instead use the system default.  Note that the queue length can
also be adjusted at runtime.

Fixes: f942dc2552b8 ('xen network backend driver')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
---
 drivers/net/xen-netback/interface.c | 4 ----
 1 file changed, 4 deletions(-)

Comments

Ross Lagerwall Oct. 6, 2023, 1:15 p.m. UTC | #1
On Thu, Oct 5, 2023 at 3:08 PM Roger Pau Monne <roger.pau@citrix.com> wrote:
>
> Do not set netback interfaces (vifs) default TX queue size to the ring size.
> The TX queue size is not related to the ring size, and using the ring size (32)
> as the queue size can lead to packet drops.  Note the TX side of the vif
> interface in the netback domain is the one receiving packets to be injected
> to the guest.
>
> Do not explicitly set the TX queue length to any value when creating the
> interface, and instead use the system default.  Note that the queue length can
> also be adjusted at runtime.
>
> Fixes: f942dc2552b8 ('xen network backend driver')
> Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
> ---

Reviewed-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Wei Liu Oct. 6, 2023, 9:44 p.m. UTC | #2
On Thu, Oct 05, 2023 at 04:08:31PM +0200, Roger Pau Monne wrote:
> Do not set netback interfaces (vifs) default TX queue size to the ring size.
> The TX queue size is not related to the ring size, and using the ring size (32)
> as the queue size can lead to packet drops.  Note the TX side of the vif
> interface in the netback domain is the one receiving packets to be injected
> to the guest.
> 
> Do not explicitly set the TX queue length to any value when creating the
> interface, and instead use the system default.  Note that the queue length can
> also be adjusted at runtime.
> 
> Fixes: f942dc2552b8 ('xen network backend driver')
> Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>

Acked-by: Wei Liu <wei.liu@kernel.org>
patchwork-bot+netdevbpf@kernel.org Oct. 8, 2023, 1:01 p.m. UTC | #3
Hello:

This patch was applied to netdev/net.git (main)
by David S. Miller <davem@davemloft.net>:

On Thu,  5 Oct 2023 16:08:31 +0200 you wrote:
> Do not set netback interfaces (vifs) default TX queue size to the ring size.
> The TX queue size is not related to the ring size, and using the ring size (32)
> as the queue size can lead to packet drops.  Note the TX side of the vif
> interface in the netback domain is the one receiving packets to be injected
> to the guest.
> 
> Do not explicitly set the TX queue length to any value when creating the
> interface, and instead use the system default.  Note that the queue length can
> also be adjusted at runtime.
> 
> [...]

Here is the summary with links:
  - xen-netback: use default TX queue size for vifs
    https://git.kernel.org/netdev/net/c/66cf7435a269

You are awesome, thank you!
diff mbox series

Patch

diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c
index f3f2c07423a6..fc3bb63b9ac3 100644
--- a/drivers/net/xen-netback/interface.c
+++ b/drivers/net/xen-netback/interface.c
@@ -41,8 +41,6 @@ 
 #include <asm/xen/hypercall.h>
 #include <xen/balloon.h>
 
-#define XENVIF_QUEUE_LENGTH 32
-
 /* Number of bytes allowed on the internal guest Rx queue. */
 #define XENVIF_RX_QUEUE_BYTES (XEN_NETIF_RX_RING_SIZE/2 * PAGE_SIZE)
 
@@ -530,8 +528,6 @@  struct xenvif *xenvif_alloc(struct device *parent, domid_t domid,
 	dev->features = dev->hw_features | NETIF_F_RXCSUM;
 	dev->ethtool_ops = &xenvif_ethtool_ops;
 
-	dev->tx_queue_len = XENVIF_QUEUE_LENGTH;
-
 	dev->min_mtu = ETH_MIN_MTU;
 	dev->max_mtu = ETH_MAX_MTU - VLAN_ETH_HLEN;