On Thu, Oct 7, 2021 at 5:19 PM Paolo Bonzini <pbonzini@redhat.com> wrote:
This makes the pthreads check dead in configure, so remove it
as well.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>

(a shame that g_system_thread_set_name() is not exported imho)

---
 configure                | 78 ----------------------------------------
 meson.build              | 23 ++++++++++++
 util/qemu-thread-posix.c |  5 ++-
 3 files changed, 25 insertions(+), 81 deletions(-)

diff --git a/configure b/configure
index 52f89b05d6..a1e142d5f8 100755
--- a/configure
+++ b/configure
@@ -3146,71 +3146,6 @@ if test "$modules" = yes; then
     fi
 fi

-##########################################
-# pthread probe
-PTHREADLIBS_LIST="-pthread -lpthread -lpthreadGC2"
-
-pthread=no
-cat > $TMPC << EOF
-#include <pthread.h>
-static void *f(void *p) { return NULL; }
-int main(void) {
-  pthread_t thread;
-  pthread_create(&thread, 0, f, 0);
-  return 0;
-}
-EOF
-if compile_prog "" "" ; then
-  pthread=yes
-else
-  for pthread_lib in $PTHREADLIBS_LIST; do
-    if compile_prog "" "$pthread_lib" ; then
-      pthread=yes
-      break
-    fi
-  done
-fi
-
-if test "$mingw32" != yes && test "$pthread" = no; then
-  error_exit "pthread check failed" \
-      "Make sure to have the pthread libs and headers installed."
-fi
-
-# check for pthread_setname_np with thread id
-pthread_setname_np_w_tid=no
-cat > $TMPC << EOF
-#include <pthread.h>
-
-static void *f(void *p) { return NULL; }
-int main(void)
-{
-    pthread_t thread;
-    pthread_create(&thread, 0, f, 0);
-    pthread_setname_np(thread, "QEMU");
-    return 0;
-}
-EOF
-if compile_prog "" "$pthread_lib" ; then
-  pthread_setname_np_w_tid=yes
-fi
-
-# check for pthread_setname_np without thread id
-pthread_setname_np_wo_tid=no
-cat > $TMPC << EOF
-#include <pthread.h>
-
-static void *f(void *p) { pthread_setname_np("QEMU"); return NULL; }
-int main(void)
-{
-    pthread_t thread;
-    pthread_create(&thread, 0, f, 0);
-    return 0;
-}
-EOF
-if compile_prog "" "$pthread_lib" ; then
-  pthread_setname_np_wo_tid=yes
-fi
-
 ##########################################
 # libssh probe
 if test "$libssh" != "no" ; then
@@ -4496,19 +4431,6 @@ if test "$debug_mutex" = "yes" ; then
   echo "CONFIG_DEBUG_MUTEX=y" >> $config_host_mak
 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_W_TID - A way of doing it on a particular
-#                                     platform
-if test "$pthread_setname_np_w_tid" = "yes" ; then
-  echo "CONFIG_THREAD_SETNAME_BYTHREAD=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" >> $config_host_mak
-fi
-
 if test "$bochs" = "yes" ; then
   echo "CONFIG_BOCHS=y" >> $config_host_mak
 fi
diff --git a/meson.build b/meson.build
index 935a20c198..54b2afdb96 100644
--- a/meson.build
+++ b/meson.build
@@ -1586,6 +1586,29 @@ config_host_data.set('CONFIG_POSIX_MADVISE', cc.links(gnu_source_prefix + '''
   #include <sys/mman.h>
   #include <stddef.h>
   int main(void) { return posix_madvise(NULL, 0, POSIX_MADV_DONTNEED); }'''))
+
+config_host_data.set('CONFIG_PTHREAD_SETNAME_NP_W_TID', cc.links('''
+  #include <pthread.h>
+
+  static void *f(void *p) { return NULL; }
+  int main(void)
+  {
+    pthread_t thread;
+    pthread_create(&thread, 0, f, 0);
+    pthread_setname_np(thread, "QEMU");
+    return 0;
+  }''', dependencies: threads))
+config_host_data.set('CONFIG_PTHREAD_SETNAME_NP_WO_TID', cc.links('''
+  #include <pthread.h>
+
+  static void *f(void *p) { pthread_setname_np("QEMU"); return NULL; }
+  int main(void)
+  {
+    pthread_t thread;
+    pthread_create(&thread, 0, f, 0);
+    return 0;
+  }''', dependencies: threads))
+
 config_host_data.set('CONFIG_SIGNALFD', cc.links(gnu_source_prefix + '''
   #include <unistd.h>
   #include <sys/syscall.h>
diff --git a/util/qemu-thread-posix.c b/util/qemu-thread-posix.c
index 6c5004220d..e1225b63bd 100644
--- a/util/qemu-thread-posix.c
+++ b/util/qemu-thread-posix.c
@@ -23,7 +23,8 @@ void qemu_thread_naming(bool enable)
 {
     name_threads = enable;

-#ifndef CONFIG_THREAD_SETNAME_BYTHREAD
+#if !defined CONFIG_PTHREAD_SETNAME_NP_W_TID && \
+    !defined CONFIG_PTHREAD_SETNAME_NP_WO_TID
     /* This is a debugging option, not fatal */
     if (enable) {
         fprintf(stderr, "qemu: thread naming not supported on this host\n");
@@ -522,7 +523,6 @@ static void *qemu_thread_start(void *args)
     void *arg = qemu_thread_args->arg;
     void *r;

-#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.
      */
@@ -533,7 +533,6 @@ static void *qemu_thread_start(void *args)
         pthread_setname_np(qemu_thread_args->name);
 # endif
     }
-#endif
     QEMU_TSAN_ANNOTATE_THREAD_NAME(qemu_thread_args->name);
     g_free(qemu_thread_args->name);
     g_free(qemu_thread_args);
--
2.31.1





--
Marc-André Lureau