rts: Fix timer initialization

Previously `initScheduler` would attempt to pause the ticker and in so
doing acquire the ticker mutex. However, initTicker, which is
responsible for initializing said mutex, hadn't been called
yet.

1 files changed, 7 insertions, 1 deletions

diff --git a/rts/RtsStartup.c b/rts/RtsStartup.c
index a3dddb03f5..6dd8c555f1 100644
--- a/rts/RtsStartup.c
+++ b/rts/RtsStartup.c
@@ -285,6 +285,13 @@ hs_init_ghc(int *argc, char **argv[], RtsConfig rts_config)
     /* Initialise libdw session pool */
     libdwPoolInit();
 
+    /* Start the "ticker" and profiling timer but don't start until the
+     * scheduler is up. However, the ticker itself needs to be initialized
+     * before the scheduler to ensure that the ticker mutex is initialized as
+     * moreCapabilities will attempt to acquire it.
+     */
+    initTimer();
+
     /* initialise scheduler data structures (needs to be done before
      * initStorage()).
      */
@@ -366,7 +373,6 @@ hs_init_ghc(int *argc, char **argv[], RtsConfig rts_config)
     initHeapProfiling();
 
     /* start the virtual timer 'subsystem'. */
-    initTimer();
     startTimer();
 
 #if defined(RTS_USER_SIGNALS)