nbd: use generic trace subsystem instead of TRACE macro

Let NBD use the trace mechanisms already present in qemu. Now you can
use the -trace optino of qemu, or the -T/--trace option of qemu-img,
qemu-io, and qemu-nbd, to select nbd traces. For qemu, the QMP commands
trace-event-{get,set}-state can also toggle tracing on the fly.

Example:
   qemu-nbd --trace 'nbd_*' <image file> # enables all nbd traces

Recompilation with CFLAGS=-DDEBUG_NBD is no more needed, furthermore,
DEBUG_NBD macro is removed from the code.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20170707152918.23086-11-vsementsov@virtuozzo.com>
[eblake: minor tweaks to a couple of traces]
Signed-off-by: Eric Blake <eblake@redhat.com>

1 files changed, 33 insertions, 37 deletions

diff --git a/nbd/server.c b/nbd/server.c
index 4bbce5fe76..9b0c588146 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -19,6 +19,7 @@
 
 #include "qemu/osdep.h"
 #include "qapi/error.h"
+#include "trace.h"
 #include "nbd-internal.h"
 
 static int system_errno_to_nbd_errno(int err)
@@ -138,8 +139,7 @@ static int nbd_negotiate_send_rep_len(QIOChannel *ioc, uint32_t type,
 {
     uint64_t magic;
 
-    TRACE("Reply opt=%" PRIx32 " type=%" PRIx32 " len=%" PRIu32,
-          opt, type, len);
+    trace_nbd_negotiate_send_rep_len(opt, type, len);
 
     magic = cpu_to_be64(NBD_REP_MAGIC);
     if (nbd_write(ioc, &magic, sizeof(magic), errp) < 0) {
@@ -191,7 +191,7 @@ nbd_negotiate_send_rep_err(QIOChannel *ioc, uint32_t type,
     va_end(va);
     len = strlen(msg);
     assert(len < 4096);
-    TRACE("sending error message \"%s\"", msg);
+    trace_nbd_negotiate_send_rep_err(msg);
     ret = nbd_negotiate_send_rep_len(ioc, type, opt, len, errp);
     if (ret < 0) {
         goto out;
@@ -219,7 +219,7 @@ static int nbd_negotiate_send_rep_list(QIOChannel *ioc, NBDExport *exp,
     const char *desc = exp->description ? exp->description : "";
     int ret;
 
-    TRACE("Advertising export name '%s' description '%s'", name, desc);
+    trace_nbd_negotiate_send_rep_list(name, desc);
     name_len = strlen(name);
     desc_len = strlen(desc);
     len = name_len + desc_len + sizeof(len);
@@ -283,7 +283,7 @@ static int nbd_negotiate_handle_export_name(NBDClient *client, uint32_t length,
     /* Client sends:
         [20 ..  xx]   export name (length bytes)
      */
-    TRACE("Checking length");
+    trace_nbd_negotiate_handle_export_name();
     if (length >= sizeof(name)) {
         error_setg(errp, "Bad length received");
         return -EINVAL;
@@ -294,7 +294,7 @@ static int nbd_negotiate_handle_export_name(NBDClient *client, uint32_t length,
     }
     name[length] = '\0';
 
-    TRACE("Client requested export '%s'", name);
+    trace_nbd_negotiate_handle_export_name_request(name);
 
     client->exp = nbd_export_find(name);
     if (!client->exp) {
@@ -318,7 +318,7 @@ static QIOChannel *nbd_negotiate_handle_starttls(NBDClient *client,
     QIOChannelTLS *tioc;
     struct NBDTLSHandshakeData data = { 0 };
 
-    TRACE("Setting up TLS");
+    trace_nbd_negotiate_handle_starttls();
     ioc = client->ioc;
     if (length) {
         if (nbd_drop(ioc, length, errp) < 0) {
@@ -344,7 +344,7 @@ static QIOChannel *nbd_negotiate_handle_starttls(NBDClient *client,
     }
 
     qio_channel_set_name(QIO_CHANNEL(tioc), "nbd-server-tls");
-    TRACE("Starting TLS handshake");
+    trace_nbd_negotiate_handle_starttls_handshake();
     data.loop = g_main_loop_new(g_main_context_default(), FALSE);
     qio_channel_tls_handshake(tioc,
                               nbd_tls_handshake,
@@ -396,15 +396,15 @@ static int nbd_negotiate_options(NBDClient *client, Error **errp)
         error_prepend(errp, "read failed: ");
         return -EIO;
     }
-    TRACE("Checking client flags");
+    trace_nbd_negotiate_options_flags();
     be32_to_cpus(&flags);
     if (flags & NBD_FLAG_C_FIXED_NEWSTYLE) {
-        TRACE("Client supports fixed newstyle handshake");
+        trace_nbd_negotiate_options_newstyle();
         fixedNewstyle = true;
         flags &= ~NBD_FLAG_C_FIXED_NEWSTYLE;
     }
     if (flags & NBD_FLAG_C_NO_ZEROES) {
-        TRACE("Client supports no zeroes at handshake end");
+        trace_nbd_negotiate_options_no_zeroes();
         client->no_zeroes = true;
         flags &= ~NBD_FLAG_C_NO_ZEROES;
     }
@@ -422,8 +422,9 @@ static int nbd_negotiate_options(NBDClient *client, Error **errp)
             error_prepend(errp, "read failed: ");
             return -EINVAL;
         }
-        TRACE("Checking opts magic");
-        if (magic != be64_to_cpu(NBD_OPTS_MAGIC)) {
+        magic = be64_to_cpu(magic);
+        trace_nbd_negotiate_options_check_magic(magic);
+        if (magic != NBD_OPTS_MAGIC) {
             error_setg(errp, "Bad magic received");
             return -EINVAL;
         }
@@ -441,7 +442,7 @@ static int nbd_negotiate_options(NBDClient *client, Error **errp)
         }
         length = be32_to_cpu(length);
 
-        TRACE("Checking option 0x%" PRIx32, option);
+        trace_nbd_negotiate_options_check_option(option);
         if (client->tlscreds &&
             client->ioc == (QIOChannel *)client->sioc) {
             QIOChannel *tioc;
@@ -501,8 +502,8 @@ static int nbd_negotiate_options(NBDClient *client, Error **errp)
                                        &local_err);
 
                 if (local_err != NULL) {
-                    TRACE("Reply to NBD_OPT_ABORT request failed: %s",
-                          error_get_pretty(local_err));
+                    const char *error = error_get_pretty(local_err);
+                    trace_nbd_opt_abort_reply_failed(error);
                     error_free(local_err);
                 }
 
@@ -599,14 +600,14 @@ static coroutine_fn int nbd_negotiate(NBDClient *client, Error **errp)
 
     qio_channel_set_blocking(client->ioc, false, NULL);
 
-    TRACE("Beginning negotiation.");
+    trace_nbd_negotiate_begin();
     memset(buf, 0, sizeof(buf));
     memcpy(buf, "NBDMAGIC", 8);
 
     oldStyle = client->exp != NULL && !client->tlscreds;
     if (oldStyle) {
-        TRACE("advertising size %" PRIu64 " and flags %x",
-              client->exp->size, client->exp->nbdflags | myflags);
+        trace_nbd_negotiate_old_style(client->exp->size,
+                                      client->exp->nbdflags | myflags);
         stq_be_p(buf + 8, NBD_CLIENT_MAGIC);
         stq_be_p(buf + 16, client->exp->size);
         stw_be_p(buf + 26, client->exp->nbdflags | myflags);
@@ -631,8 +632,8 @@ static coroutine_fn int nbd_negotiate(NBDClient *client, Error **errp)
             return ret;
         }
 
-        TRACE("advertising size %" PRIu64 " and flags %x",
-              client->exp->size, client->exp->nbdflags | myflags);
+        trace_nbd_negotiate_new_style_size_flags(
+            client->exp->size, client->exp->nbdflags | myflags);
         stq_be_p(buf + 18, client->exp->size);
         stw_be_p(buf + 26, client->exp->nbdflags | myflags);
         len = client->no_zeroes ? 10 : sizeof(buf) - 18;
@@ -643,7 +644,7 @@ static coroutine_fn int nbd_negotiate(NBDClient *client, Error **errp)
         }
     }
 
-    TRACE("Negotiation succeeded.");
+    trace_nbd_negotiate_success();
 
     return 0;
 }
@@ -676,9 +677,8 @@ static int nbd_receive_request(QIOChannel *ioc, NBDRequest *request,
     request->from   = ldq_be_p(buf + 16);
     request->len    = ldl_be_p(buf + 24);
 
-    TRACE("Got request: { magic = 0x%" PRIx32 ", .flags = %" PRIx16
-          ", .type = %" PRIx16 ", from = %" PRIu64 ", len = %" PRIu32 " }",
-          magic, request->flags, request->type, request->from, request->len);
+    trace_nbd_receive_request(magic, request->flags, request->type,
+                              request->from, request->len);
 
     if (magic != NBD_REQUEST_MAGIC) {
         error_setg(errp, "invalid magic (got 0x%" PRIx32 ")", magic);
@@ -693,9 +693,7 @@ static int nbd_send_reply(QIOChannel *ioc, NBDReply *reply, Error **errp)
 
     reply->error = system_errno_to_nbd_errno(reply->error);
 
-    TRACE("Sending response to client: { .error = %" PRId32
-          ", handle = %" PRIu64 " }",
-          reply->error, reply->handle);
+    trace_nbd_send_reply(reply->error, reply->handle);
 
     /* Reply
        [ 0 ..  3]    magic   (NBD_REPLY_MAGIC)
@@ -792,7 +790,7 @@ static void blk_aio_attached(AioContext *ctx, void *opaque)
     NBDExport *exp = opaque;
     NBDClient *client;
 
-    TRACE("Export %s: Attaching clients to AIO context %p\n", exp->name, ctx);
+    trace_nbd_blk_aio_attached(exp->name, ctx);
 
     exp->ctx = ctx;
 
@@ -812,7 +810,7 @@ static void blk_aio_detach(void *opaque)
     NBDExport *exp = opaque;
     NBDClient *client;
 
-    TRACE("Export %s: Detaching clients from AIO context %p\n", exp->name, exp->ctx);
+    trace_nbd_blk_aio_detach(exp->name, exp->ctx);
 
     QTAILQ_FOREACH(client, &exp->clients, next) {
         qio_channel_detach_aio_context(client->ioc);
@@ -1001,8 +999,7 @@ static int nbd_co_send_reply(NBDRequestData *req, NBDReply *reply, int len,
 
     g_assert(qemu_in_coroutine());
 
-    TRACE("Send reply: handle = %" PRIu64 ", error = %" PRIu32 ", len = %d",
-          reply->handle, reply->error, len);
+    trace_nbd_co_send_reply(reply->handle, reply->error, len);
 
     qemu_co_mutex_lock(&client->send_lock);
     client->send_coroutine = qemu_coroutine_self();
@@ -1043,8 +1040,7 @@ static int nbd_co_receive_request(NBDRequestData *req, NBDRequest *request,
         return -EIO;
     }
 
-    TRACE("Decoding type: handle = %" PRIu64 ", type = %" PRIu16,
-          request->handle, request->type);
+    trace_nbd_co_receive_request_decode_type(request->handle, request->type);
 
     if (request->type != NBD_CMD_WRITE) {
         /* No payload, we are ready to read the next request.  */
@@ -1086,8 +1082,8 @@ static int nbd_co_receive_request(NBDRequestData *req, NBDRequest *request,
         }
         req->complete = true;
 
-        TRACE("Payload received: handle = %" PRIu64 ", len = %" PRIu32,
-              request->handle, request->len);
+        trace_nbd_co_receive_request_payload_received(request->handle,
+                                                      request->len);
     }
 
     /* Sanity checks, part 2. */
@@ -1123,7 +1119,7 @@ static coroutine_fn void nbd_trip(void *opaque)
     int reply_data_len = 0;
     Error *local_err = NULL;
 
-    TRACE("Reading request.");
+    trace_nbd_trip();
     if (client->closing) {
         nbd_client_put(client);
         return;