Re: [PATCH-for-5.1] net/colo: Remove unused trace event

[Roman Bolshakov <r.bolshakov@yadro.com>]

On Wed, Jul 15, 2020 at 04:31:30PM +0200, Philippe Mathieu-Daudé wrote:
> Unused trace event cause build failure when using the dtrace backend:
> 
>   "probe colo_compare_miscompare doesn't exist"
> 
> Fixes: f4b618360e ("colo-compare: add TCP, UDP, ICMP packet comparison")
> Reported-by: Roman Bolshakov <r.bolshakov@yadro.com>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---
> Cc: zhangchen.fnst@cn.fujitsu.com
> ---
>  net/trace-events | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/net/trace-events b/net/trace-events
> index fa49c71533..c3f623d40c 100644
> --- a/net/trace-events
> +++ b/net/trace-events
> @@ -17,7 +17,6 @@ colo_compare_udp_miscompare(const char *sta, int size) ": %s = %d"
>  colo_compare_icmp_miscompare(const char *sta, int size) ": %s = %d"
>  colo_compare_ip_info(int psize, const char *sta, const char *stb, int ssize, const char *stc, const char *std) "ppkt size = %d, ip_src = %s, ip_dst = %s, spkt size = %d, ip_src = %s, ip_dst = %s"
>  colo_old_packet_check_found(int64_t old_time) "%" PRId64
> -colo_compare_miscompare(void) ""
>  colo_compare_tcp_info(const char *pkt, uint32_t seq, uint32_t ack, int hdlen, int pdlen, int offset, int flags) "%s: seq/ack= %u/%u hdlen= %d pdlen= %d offset= %d flags=%d"
>  
>  # filter-rewriter.c
> -- 
> 2.21.3
> 

Hi Philippe,

Thanks for submitting it but this is not enough, here's the patch that
works (but this is only one of the patches that enables dtrace on macOS):

diff --git a/net/trace-events b/net/trace-events
index fa49c71533..c3f623d40c 100644
--- a/net/trace-events
+++ b/net/trace-events
@@ -17,7 +17,6 @@ colo_compare_udp_miscompare(const char *sta, int size) ": %s = %d"
 colo_compare_icmp_miscompare(const char *sta, int size) ": %s = %d"
 colo_compare_ip_info(int psize, const char *sta, const char *stb, int ssize, const char *stc, const char *std) "ppkt size = %d, ip_src = %s, ip_dst = %s, spkt size = %d, ip_src = %s, ip_dst = %s"
 colo_old_packet_check_found(int64_t old_time) "%" PRId64
-colo_compare_miscompare(void) ""
 colo_compare_tcp_info(const char *pkt, uint32_t seq, uint32_t ack, int hdlen, int pdlen, int offset, int flags) "%s: seq/ack= %u/%u hdlen= %d pdlen= %d offset= %d flags=%d"

 # filter-rewriter.c
diff --git a/net/colo-compare.c b/net/colo-compare.c
index 398b7546ff..9525ed703b 100644
--- a/net/colo-compare.c
+++ b/net/colo-compare.c
@@ -327,7 +327,7 @@ static int colo_compare_packet_payload(Packet *ppkt,
                                        uint16_t len)

 {
-    if (trace_event_get_state_backends(TRACE_COLO_COMPARE_MISCOMPARE)) {
+    if (trace_event_get_state_backends(TRACE_COLO_COMPARE_IP_INFO)) {
         char pri_ip_src[20], pri_ip_dst[20], sec_ip_src[20], sec_ip_dst[20];

         strcpy(pri_ip_src, inet_ntoa(ppkt->ip->ip_src));
@@ -492,7 +492,7 @@ sec:
         g_queue_push_head(&conn->primary_list, ppkt);
         g_queue_push_head(&conn->secondary_list, spkt);

-        if (trace_event_get_state_backends(TRACE_COLO_COMPARE_MISCOMPARE)) {
+        if (trace_event_get_state_backends(TRACE_COLO_COMPARE_TCP_INFO)) {
             qemu_hexdump((char *)ppkt->data, stderr,
                         "colo-compare ppkt", ppkt->size);
             qemu_hexdump((char *)spkt->data, stderr,
@@ -533,7 +533,8 @@ static int colo_packet_compare_udp(Packet *spkt, Packet *ppkt)
                                     ppkt->size - offset)) {
         trace_colo_compare_udp_miscompare("primary pkt size", ppkt->size);
         trace_colo_compare_udp_miscompare("Secondary pkt size", spkt->size);
-        if (trace_event_get_state_backends(TRACE_COLO_COMPARE_MISCOMPARE)) {
+        if (trace_event_get_state_backends(
+              TRACE_COLO_COMPARE_UDP_MISCOMPARE)) {
             qemu_hexdump((char *)ppkt->data, stderr, "colo-compare pri pkt",
                          ppkt->size);
             qemu_hexdump((char *)spkt->data, stderr, "colo-compare sec pkt",
@@ -576,7 +577,8 @@ static int colo_packet_compare_icmp(Packet *spkt, Packet *ppkt)
                                            ppkt->size);
         trace_colo_compare_icmp_miscompare("Secondary pkt size",
                                            spkt->size);
-        if (trace_event_get_state_backends(TRACE_COLO_COMPARE_MISCOMPARE)) {
+        if (trace_event_get_state_backends(
+              TRACE_COLO_COMPARE_ICMP_MISCOMPARE)) {
             qemu_hexdump((char *)ppkt->data, stderr, "colo-compare pri pkt",
                          ppkt->size);
             qemu_hexdump((char *)spkt->data, stderr, "colo-compare sec pkt",
@@ -597,7 +599,7 @@ static int colo_packet_compare_other(Packet *spkt, Packet *ppkt)
     uint16_t offset = ppkt->vnet_hdr_len;

     trace_colo_compare_main("compare other");
-    if (trace_event_get_state_backends(TRACE_COLO_COMPARE_MISCOMPARE)) {
+    if (trace_event_get_state_backends(TRACE_COLO_COMPARE_IP_INFO)) {
         char pri_ip_src[20], pri_ip_dst[20], sec_ip_src[20], sec_ip_dst[20];

         strcpy(pri_ip_src, inet_ntoa(ppkt->ip->ip_src));
diff --git a/net/filter-rewriter.c b/net/filter-rewriter.c
index 1aaad101b6..875a9ad7a4 100644
--- a/net/filter-rewriter.c
+++ b/net/filter-rewriter.c
@@ -76,7 +76,8 @@ static int handle_primary_tcp_pkt(RewriterState *rf,
     struct tcp_hdr *tcp_pkt;

     tcp_pkt = (struct tcp_hdr *)pkt->transport_header;
-    if (trace_event_get_state_backends(TRACE_COLO_FILTER_REWRITER_DEBUG)) {
+    if (trace_event_get_state_backends(
+          TRACE_COLO_FILTER_REWRITER_CONN_OFFSET)) {
         trace_colo_filter_rewriter_pkt_info(__func__,
                     inet_ntoa(pkt->ip->ip_src), inet_ntoa(pkt->ip->ip_dst),
                     ntohl(tcp_pkt->th_seq), ntohl(tcp_pkt->th_ack),
@@ -180,7 +181,8 @@ static int handle_secondary_tcp_pkt(RewriterState *rf,

     tcp_pkt = (struct tcp_hdr *)pkt->transport_header;

-    if (trace_event_get_state_backends(TRACE_COLO_FILTER_REWRITER_DEBUG)) {
+    if (trace_event_get_state_backends(
+          TRACE_COLO_FILTER_REWRITER_CONN_OFFSET)) {
         trace_colo_filter_rewriter_pkt_info(__func__,
                     inet_ntoa(pkt->ip->ip_src), inet_ntoa(pkt->ip->ip_dst),
                     ntohl(tcp_pkt->th_seq), ntohl(tcp_pkt->th_ack),