Increase the gdb-remote packet timeout for the first packet we send

to the remote side (QStartNoAckMode) - it may take a little longer
than normal to get a reply.

In debugserver, hardcode the priority for several threads so they
aren't de-prioritized when a user app is using system resources.
Also, set the names of the threads.

<rdar://problem/17509866>

llvm-svn: 213828

lldb/tools/debugserver/source/debugserver.cpp

@@ -25,6 +25,10 @@
 #include <sys/types.h>
 #include <crt_externs.h> // for _NSGetEnviron()
 
+#if defined (__APPLE__)
+#include <sched.h>
+#endif
+
 #include "CFString.h"
 #include "DNB.h"
 #include "DNBLog.h"
@@ -877,6 +881,19 @@ main (int argc, char *argv[])
 {
     const char *argv_sub_zero = argv[0]; // save a copy of argv[0] for error reporting post-launch
 
+#if defined (__APPLE__)
+    pthread_setname_np ("main thread");
+#if defined (__arm__) || defined (__arm64__) || defined (__aarch64__)
+    struct sched_param thread_param;
+    int thread_sched_policy;
+    if (pthread_getschedparam(pthread_self(), &thread_sched_policy, &thread_param) == 0) 
+    {
+        thread_param.sched_priority = 47;
+        pthread_setschedparam(pthread_self(), thread_sched_policy, &thread_param);
+    }
+#endif
+#endif
+
     g_isatty = ::isatty (STDIN_FILENO);
 
     //  ::printf ("uid=%u euid=%u gid=%u egid=%u\n",