diff mbox series

[net,v3] octeon_ep: update BQL sent bytes before ringing doorbell

Message ID 20231017105030.2310966-1-srasheed@marvell.com (mailing list archive)
State Accepted
Commit a0ca6b9dfef0b3cc83aa8bb485ed61a018f84982
Delegated to: Netdev Maintainers
Headers show
Series [net,v3] octeon_ep: update BQL sent bytes before ringing doorbell | expand

Checks

Context Check Description
netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for net
netdev/fixes_present success Fixes tag present in non-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 fail 2 blamed authors not CCed: aayarekar@marvell.com sburla@marvell.com; 2 maintainers not CCed: aayarekar@marvell.com sburla@marvell.com
netdev/build_clang success Errors and warnings before: 1386 this patch: 1386
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: 1386 this patch: 1386
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 26 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Shinas Rasheed Oct. 17, 2023, 10:50 a.m. UTC
Sometimes Tx is completed immediately after doorbell is updated, which
causes Tx completion routing to update completion bytes before the
same packet bytes are updated in sent bytes in transmit function, hence
hitting BUG_ON() in dql_completed(). To avoid this, update BQL
sent bytes before ringing doorbell.

Fixes: 37d79d059606 ("octeon_ep: add Tx/Rx processing and interrupt support")
Signed-off-by: Shinas Rasheed <srasheed@marvell.com>
---
V3:
  - Update skb timestamp and host write index before memory barrier
V2: https://lore.kernel.org/all/20231012101706.2291551-1-srasheed@marvell.com/
  - Call netdev_tx_sent_queue before memory barrier
V1: https://lore.kernel.org/all/20231010115015.2279977-1-srasheed@marvell.com/

 drivers/net/ethernet/marvell/octeon_ep/octep_main.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

Comments

patchwork-bot+netdevbpf@kernel.org Oct. 19, 2023, 1:10 a.m. UTC | #1
Hello:

This patch was applied to netdev/net.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Tue, 17 Oct 2023 03:50:30 -0700 you wrote:
> Sometimes Tx is completed immediately after doorbell is updated, which
> causes Tx completion routing to update completion bytes before the
> same packet bytes are updated in sent bytes in transmit function, hence
> hitting BUG_ON() in dql_completed(). To avoid this, update BQL
> sent bytes before ringing doorbell.
> 
> Fixes: 37d79d059606 ("octeon_ep: add Tx/Rx processing and interrupt support")
> Signed-off-by: Shinas Rasheed <srasheed@marvell.com>
> 
> [...]

Here is the summary with links:
  - [net,v3] octeon_ep: update BQL sent bytes before ringing doorbell
    https://git.kernel.org/netdev/net/c/a0ca6b9dfef0

You are awesome, thank you!
diff mbox series

Patch

diff --git a/drivers/net/ethernet/marvell/octeon_ep/octep_main.c b/drivers/net/ethernet/marvell/octeon_ep/octep_main.c
index dbc518ff8276..5b46ca47c8e5 100644
--- a/drivers/net/ethernet/marvell/octeon_ep/octep_main.c
+++ b/drivers/net/ethernet/marvell/octeon_ep/octep_main.c
@@ -715,20 +715,19 @@  static netdev_tx_t octep_start_xmit(struct sk_buff *skb,
 		hw_desc->dptr = tx_buffer->sglist_dma;
 	}
 
-	/* Flush the hw descriptor before writing to doorbell */
-	wmb();
-
-	/* Ring Doorbell to notify the NIC there is a new packet */
-	writel(1, iq->doorbell_reg);
+	netdev_tx_sent_queue(iq->netdev_q, skb->len);
+	skb_tx_timestamp(skb);
 	atomic_inc(&iq->instr_pending);
 	wi++;
 	if (wi == iq->max_count)
 		wi = 0;
 	iq->host_write_index = wi;
+	/* Flush the hw descriptor before writing to doorbell */
+	wmb();
 
-	netdev_tx_sent_queue(iq->netdev_q, skb->len);
+	/* Ring Doorbell to notify the NIC there is a new packet */
+	writel(1, iq->doorbell_reg);
 	iq->stats.instr_posted++;
-	skb_tx_timestamp(skb);
 	return NETDEV_TX_OK;
 
 dma_map_sg_err: