Merge branch 'egil/erl_driver-thread-info/OTP-11303' into maint

* egil/erl_driver-thread-info/OTP-11303:
  erts: Document erl_driver interface lock names
  erts: Extend erl_driver interface with lock names

3 files changed, 124 insertions, 4 deletions

diff --git a/erts/doc/src/erl_driver.xml b/erts/doc/src/erl_driver.xml
index 540390e1b1..c055d1ca9e 100644
--- a/erts/doc/src/erl_driver.xml
+++ b/erts/doc/src/erl_driver.xml
@@ -2907,8 +2907,84 @@ ERL_DRV_EXT2TERM     char *buf, ErlDrvUInt len
 	beginning of this document.</p>
       </desc>
     </func>
-  </funcs>
 
+	<func>
+		<name><ret>char *</ret><nametext>erl_drv_cond_name(ErlDrvCond *cnd)</nametext></name>
+		<fsummary>Get name of driver mutex.</fsummary>
+		<desc>
+			<marker id="erl_drv_cnd_name"></marker>
+			<p>Arguments:</p>
+			<taglist>
+				<tag><c>cnd</c></tag>
+				<item>A pointer to an initialized condition.</item>
+			</taglist>
+			<p>
+				Returns a pointer to the name of the condition.
+			</p>
+			<note>
+				<p>This function is intended for debugging purposes only.</p>
+			</note>
+		</desc>
+	</func>
+
+	<func>
+		<name><ret>char *</ret><nametext>erl_drv_mutex_name(ErlDrvMutex *mtx)</nametext></name>
+		<fsummary>Get name of driver mutex.</fsummary>
+		<desc>
+			<marker id="erl_drv_mutex_name"></marker>
+			<p>Arguments:</p>
+			<taglist>
+				<tag><c>mtx</c></tag>
+				<item>A pointer to an initialized mutex.</item>
+			</taglist>
+			<p>
+				Returns a pointer to the name of the mutex.
+			</p>
+			<note>
+				<p>This function is intended for debugging purposes only.</p>
+			</note>
+		</desc>
+	</func>
+
+	<func>
+		<name><ret>char *</ret><nametext>erl_drv_rwlock_name(ErlDrvRWLock *rwlck)</nametext></name>
+		<fsummary>Get name of driver mutex.</fsummary>
+		<desc>
+			<marker id="erl_drv_rwlock_name"></marker>
+			<p>Arguments:</p>
+			<taglist>
+				<tag><c>rwlck</c></tag>
+				<item>A pointer to an initialized r/w-lock.</item>
+			</taglist>
+			<p>
+				Returns a pointer to the name of the r/w-lock.
+			</p>
+			<note>
+				<p>This function is intended for debugging purposes only.</p>
+			</note>
+		</desc>
+	</func>
+
+	<func>
+		<name><ret>char *</ret><nametext>erl_drv_thread_name(ErlDrvTid tid)</nametext></name>
+		<fsummary>Get name of driver mutex.</fsummary>
+		<desc>
+			<marker id="erl_drv_rwlock_name"></marker>
+			<p>Arguments:</p>
+			<taglist>
+				<tag><c>tid</c></tag>
+				<item>A thread identifier.</item>
+			</taglist>
+			<p>
+				Returns a pointer to the name of the thread.
+			</p>
+			<note>
+				<p>This function is intended for debugging purposes only.</p>
+			</note>
+		</desc>
+	</func>
+
+  </funcs>
   <section>
     <title>SEE ALSO</title>
     <p><seealso marker="driver_entry">driver_entry(3)</seealso>,
diff --git a/erts/emulator/beam/erl_driver.h b/erts/emulator/beam/erl_driver.h
index 1ab6e17f56..b68fd46fcc 100644
--- a/erts/emulator/beam/erl_driver.h
+++ b/erts/emulator/beam/erl_driver.h
@@ -546,6 +546,11 @@ EXTERN int erl_drv_equal_tids(ErlDrvTid tid1, ErlDrvTid tid2);
 EXTERN void erl_drv_thread_exit(void *resp);
 EXTERN int erl_drv_thread_join(ErlDrvTid, void **respp);
 
+EXTERN char* erl_drv_mutex_name(ErlDrvMutex *mtx);
+EXTERN char* erl_drv_cond_name(ErlDrvCond *cnd);
+EXTERN char* erl_drv_rwlock_name(ErlDrvRWLock *rwlck);
+EXTERN char* erl_drv_thread_name(ErlDrvTid tid);
+
 /*
  * Misc.
  */
@@ -683,6 +688,3 @@ EXTERN int erl_drv_getenv(char *key, char *value, size_t *value_size);
 
 /* also in global.h, but driver's can't include global.h */
 void dtrace_drvport_str(ErlDrvPort port, char *port_buf);
-
-
-
diff --git a/erts/emulator/beam/erl_drv_thread.c b/erts/emulator/beam/erl_drv_thread.c
index a49a155701..4f1bba8657 100644
--- a/erts/emulator/beam/erl_drv_thread.c
+++ b/erts/emulator/beam/erl_drv_thread.c
@@ -188,6 +188,17 @@ erl_drv_mutex_destroy(ErlDrvMutex *dmtx)
 #endif
 }
 
+
+char *
+erl_drv_mutex_name(ErlDrvMutex *dmtx)
+{
+#ifdef USE_THREADS
+    return dmtx ? dmtx->name : NULL;
+#else
+    return NULL;
+#endif
+}
+
 int
 erl_drv_mutex_trylock(ErlDrvMutex *dmtx)
 {
@@ -258,6 +269,15 @@ erl_drv_cond_destroy(ErlDrvCond *dcnd)
 #endif
 }
 
+char *
+erl_drv_cond_name(ErlDrvCond *dcnd)
+{
+#ifdef USE_THREADS
+    return dcnd ? dcnd->name : NULL;
+#else
+    return NULL;
+#endif
+}
 
 void
 erl_drv_cond_signal(ErlDrvCond *dcnd)
@@ -331,6 +351,16 @@ erl_drv_rwlock_destroy(ErlDrvRWLock *drwlck)
 #endif
 }
 
+char *
+erl_drv_rwlock_name(ErlDrvRWLock *drwlck)
+{
+#ifdef USE_THREADS
+    return drwlck ? drwlck->name : NULL;
+#else
+    return NULL;
+#endif
+}
+
 int
 erl_drv_rwlock_tryrlock(ErlDrvRWLock *drwlck)
 {
@@ -617,6 +647,18 @@ erl_drv_thread_create(char *name,
 #endif
 }
 
+char *
+erl_drv_thread_name(ErlDrvTid tid)
+{
+#ifdef USE_THREADS
+    struct ErlDrvTid_ *dtid = (struct ErlDrvTid_ *) tid;
+    return dtid ? dtid->name : NULL;
+#else
+    return NULL;
+#endif
+}
+
+
 ErlDrvTid
 erl_drv_thread_self(void)
 {