Re: [PATCH net-next v2 4/7] selftests: drv-net: refactor so_txtime errqueue handling

From: Willem de Bruijn <willemb@google.com>

Prepare error queue handling for upcoming SO_EE_ORIGIN_TIMESTAMPING
messages in the next patch in this series.

Convert do_recv_errqueue_timeout into dispatcher do_recv_errqueue
and move SO_EE_ORIGIN_TXTIME specific code into a separate helper.

This will make the next patch a lot more readable.

No functional changes.

Signed-off-by: Willem de Bruijn <willemb@google.com>
---
  .../testing/selftests/drivers/net/so_txtime.c | 66 ++++++++++---------
  1 file changed, 36 insertions(+), 30 deletions(-)

diff --git a/tools/testing/selftests/drivers/net/so_txtime.c b/tools/testing/selftests/drivers/net/so_txtime.c
index 55a386f3d1b9..7364ce2bec0b 100644
--- a/tools/testing/selftests/drivers/net/so_txtime.c
+++ b/tools/testing/selftests/drivers/net/so_txtime.c

@@ -158,7 +158,40 @@ static void do_recv_verify_empty(int fdr)
  		error(1, 0, "recv: not empty as expected (%d, %d)", ret, errno);
  }
  
-static int do_recv_errqueue_timeout(int fdt)
+static int do_recv_errqueue_timeout(struct sock_extended_err *err,
+				    const char payload_char)
+{
+	const char *reason = NULL;
+	int64_t tstamp = 0;
+
+	switch (err->ee_errno) {
+	case ECANCELED:
+		if (err->ee_code != SO_EE_CODE_TXTIME_MISSED)
+			error(1, 0, "errqueue: unknown ECANCELED %u\n",
+			      err->ee_code);
+		reason = "missed txtime";
+	break;
+	case EINVAL:
+		if (err->ee_code != SO_EE_CODE_TXTIME_INVALID_PARAM)
+			error(1, 0, "errqueue: unknown EINVAL %u\n",
+			      err->ee_code);
+		reason = "invalid txtime";
+	break;
+	default:
+		error(1, 0, "errqueue: errno %u code %u\n",
+		      err->ee_errno, err->ee_code);
+	}
+
+	tstamp = ((int64_t)err->ee_data) << 32 | err->ee_info;
+	tstamp -= (int64_t)glob_tstart;
+	tstamp /= 1000 * 1000;
+	fprintf(stderr, "send: pkt %c at %" PRId64 "ms dropped: %s\n",
+		payload_char, tstamp, reason);
+
+	return 1;
+}
+
+static int do_recv_errqueue(int fdt)
  {
  	char control[CMSG_SPACE(sizeof(struct sock_extended_err)) +
  		     CMSG_SPACE(sizeof(struct sockaddr_in6))] = {0};

@@ -169,7 +202,6 @@ static int do_recv_errqueue_timeout(int fdt)
  	struct msghdr msg = {0};
  	struct iovec iov = {0};
  	struct cmsghdr *cm;
-	int64_t tstamp = 0;
  
  	iov.iov_base = data;
  	iov.iov_len = sizeof(data);

@@ -181,8 +213,6 @@ static int do_recv_errqueue_timeout(int fdt)
  	msg.msg_controllen = sizeof(control);
  
  	while (1) {
-		const char *reason = NULL;
-
  		ret = recvmsg(fdt, &msg, MSG_ERRQUEUE);
  		if (ret == -1 && errno == EAGAIN)
  			break;

@@ -201,33 +231,9 @@ static int do_recv_errqueue_timeout(int fdt)
  		if (err->ee_origin != SO_EE_ORIGIN_TXTIME)
  			error(1, 0, "errqueue: origin 0x%x\n", err->ee_origin);
  
-		switch (err->ee_errno) {
-		case ECANCELED:
-			if (err->ee_code != SO_EE_CODE_TXTIME_MISSED)
-				error(1, 0, "errqueue: unknown ECANCELED %u\n",
-				      err->ee_code);
-			reason = "missed txtime";
-		break;
-		case EINVAL:
-			if (err->ee_code != SO_EE_CODE_TXTIME_INVALID_PARAM)
-				error(1, 0, "errqueue: unknown EINVAL %u\n",
-				      err->ee_code);
-			reason = "invalid txtime";
-		break;
-		default:
-			error(1, 0, "errqueue: errno %u code %u\n",
-			      err->ee_errno, err->ee_code);
-		}
-
-		tstamp = ((int64_t) err->ee_data) << 32 | err->ee_info;
-		tstamp -= (int64_t) glob_tstart;
-		tstamp /= 1000 * 1000;
-		fprintf(stderr, "send: pkt %c at %" PRId64 "ms dropped: %s\n",
-			data[ret - 1], tstamp, reason);
-
+		num_tstamp += do_recv_errqueue_timeout(err, data[ret - 1]);
  		msg.msg_flags = 0;
  		msg.msg_controllen = sizeof(control);
-		num_tstamp++;
  	}
  
  	return num_tstamp;

@@ -245,7 +251,7 @@ static void recv_errqueue_msgs(int fdt)
  			error(1, errno, "poll");
  
  		if (ret && (pfd.revents & POLLERR))
-			num_tstamp += do_recv_errqueue_timeout(fdt);
+			num_tstamp += do_recv_errqueue(fdt);
  
  		if (num_tstamp == cfg_num_pkt)
  			break;