[Qemu-devel] [RFC 1/2] util: Implement debug-threads for macOS

[Roman Bolshakov]

macOS provides pthread_setname_np that doesn't have thread id argument.

Signed-off-by: Roman Bolshakov <address@hidden>
---
 configure                | 32 ++++++++++++++++++++++++++------
 qemu-options.hx          |  4 ++--
 util/qemu-thread-posix.c |  6 +++++-
 3 files changed, 33 insertions(+), 9 deletions(-)

diff --git a/configure b/configure
index 224d3071ac..99dc073e53 100755
--- a/configure
+++ b/configure
@@ -3715,8 +3715,8 @@ if test "$mingw32" != yes -a "$pthread" = no; then
       "Make sure to have the pthread libs and headers installed."
 fi
 
-# check for pthread_setname_np
-pthread_setname_np=no
+# check for pthread_setname_np with thread id
+pthread_setname_np_w_tid=no
 cat > $TMPC << EOF
 #include <pthread.h>
 
@@ -3730,7 +3730,24 @@ int main(void)
 }
 EOF
 if compile_prog "" "$pthread_lib" ; then
-  pthread_setname_np=yes
+  pthread_setname_np_w_tid=yes
+fi
+
+# check for pthread_setname_np without thread id
+pthread_setname_np_wo_tid=no
+cat > $TMPC << EOF
+#include <pthread.h>
+
+static void *f(void *p) { pthread_setname_np("QEMU"); }
+int main(void)
+{
+    pthread_t thread;
+    pthread_create(&thread, 0, f, 0);
+    return 0;
+}
+EOF
+if compile_prog "" "$pthread_lib" ; then
+  pthread_setname_np_wo_tid=yes
 fi
 
 ##########################################
@@ -6883,11 +6900,14 @@ fi
 # Hold two types of flag:
 #   CONFIG_THREAD_SETNAME_BYTHREAD  - we've got a way of setting the name on
 #                                     a thread we have a handle to
-#   CONFIG_PTHREAD_SETNAME_NP       - A way of doing it on a particular
+#   CONFIG_PTHREAD_SETNAME_NP_W_TID - A way of doing it on a particular
 #                                     platform
-if test "$pthread_setname_np" = "yes" ; then
+if test "$pthread_setname_np_w_tid" = "yes" ; then
   echo "CONFIG_THREAD_SETNAME_BYTHREAD=y" >> $config_host_mak
-  echo "CONFIG_PTHREAD_SETNAME_NP=y" >> $config_host_mak
+  echo "CONFIG_PTHREAD_SETNAME_NP_W_TID=y" >> $config_host_mak
+elif test "$pthread_setname_np_wo_tid" = "yes" ; then
+  echo "CONFIG_THREAD_SETNAME_BYTHREAD=y" >> $config_host_mak
+  echo "CONFIG_PTHREAD_SETNAME_NP_WO_TID=y" >> $config_host_mak
 fi
 
 if test "$vxhs" = "yes" ; then
diff --git a/qemu-options.hx b/qemu-options.hx
index df42116ecc..d4f3564b78 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -538,8 +538,8 @@ ETEXI
 DEF("name", HAS_ARG, QEMU_OPTION_name,
     "-name string1[,process=string2][,debug-threads=on|off]\n"
     "                set the name of the guest\n"
-    "                string1 sets the window title and string2 the process 
name (on Linux)\n"
-    "                When debug-threads is enabled, individual threads are 
given a separate name (on Linux)\n"
+    "                string1 sets the window title and string2 the process 
name\n"
+    "                When debug-threads is enabled, individual threads are 
given a separate name\n"
     "                NOTE: The thread names are for debugging and not a stable 
API.\n",
     QEMU_ARCH_ALL)
 STEXI
diff --git a/util/qemu-thread-posix.c b/util/qemu-thread-posix.c
index 865e476df5..c6934bd22c 100644
--- a/util/qemu-thread-posix.c
+++ b/util/qemu-thread-posix.c
@@ -484,12 +484,16 @@ static void *qemu_thread_start(void *args)
     void *arg = qemu_thread_args->arg;
     void *r;
 
-#ifdef CONFIG_PTHREAD_SETNAME_NP
+#ifdef CONFIG_THREAD_SETNAME_BYTHREAD
     /* Attempt to set the threads name; note that this is for debug, so
      * we're not going to fail if we can't set it.
      */
     if (name_threads && qemu_thread_args->name) {
+# if defined(CONFIG_PTHREAD_SETNAME_NP_W_TID)
         pthread_setname_np(pthread_self(), qemu_thread_args->name);
+# elif defined(CONFIG_PTHREAD_SETNAME_NP_WO_TID)
+        pthread_setname_np(qemu_thread_args->name);
+# endif
     }
 #endif
     g_free(qemu_thread_args->name);
-- 
2.19.1