diff mbox series

[net,5/9] idpf: set completion tag for "empty" bufs associated with a packet

Message ID 20241203215521.1646668-6-anthony.l.nguyen@intel.com (mailing list archive)
State New
Delegated to: Netdev Maintainers
Headers show
Series Intel Wired LAN Driver Updates 2024-12-03 (ice, idpf, ixgbe, ixgbevf, igb) | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
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: 3 this patch: 3
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 5 of 5 maintainers
netdev/build_clang success Errors and warnings before: 3 this patch: 3
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: 304 this patch: 304
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 7 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 50 this patch: 50
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-12-04--15-02 (tests: 760)

Commit Message

Tony Nguyen Dec. 3, 2024, 9:55 p.m. UTC 
From: Joshua Hay <joshua.a.hay@intel.com>

Commit d9028db618a6 ("idpf: convert to libeth Tx buffer completion")
inadvertently removed code that was necessary for the tx buffer cleaning
routine to iterate over all buffers associated with a packet.

When a frag is too large for a single data descriptor, it will be split
across multiple data descriptors. This means the frag will span multiple
buffers in the buffer ring in order to keep the descriptor and buffer
ring indexes aligned. The buffer entries in the ring are technically
empty and no cleaning actions need to be performed. These empty buffers
can precede other frags associated with the same packet. I.e. a single
packet on the buffer ring can look like:

	buf[0]=skb0.frag0
	buf[1]=skb0.frag1
	buf[2]=empty
	buf[3]=skb0.frag2

The cleaning routine iterates through these buffers based on a matching
completion tag. If the completion tag is not set for buf2, the loop will
end prematurely. Frag2 will be left uncleaned and next_to_clean will be
left pointing to the end of packet, which will break the cleaning logic
for subsequent cleans. This consequently leads to tx timeouts.

Assign the empty bufs the same completion tag for the packet to ensure
the cleaning routine iterates over all of the buffers associated with
the packet.

Fixes: d9028db618a6 ("idpf: convert to libeth Tx buffer completion")
Signed-off-by: Joshua Hay <joshua.a.hay@intel.com>
Acked-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Madhu chittim <madhu.chittim@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Krishneil Singh <krishneil.k.singh@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
---
 drivers/net/ethernet/intel/idpf/idpf_txrx.c | 1 +
 1 file changed, 1 insertion(+)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/intel/idpf/idpf_txrx.c b/drivers/net/ethernet/intel/idpf/idpf_txrx.c
index da2a5becf62f..34f4118c7bc0 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_txrx.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_txrx.c
@@ -2448,6 +2448,7 @@  static void idpf_tx_splitq_map(struct idpf_tx_queue *tx_q,
 			 * rest of the packet.
 			 */
 			tx_buf->type = LIBETH_SQE_EMPTY;
+			idpf_tx_buf_compl_tag(tx_buf) = params->compl_tag;
 
 			/* Adjust the DMA offset and the remaining size of the
 			 * fragment.  On the first iteration of this loop,