[DTrace-devel] [PATCH v2 1/4] port: delete useless mutex.h and mutex_* wrappers

[Nick Alcock]

These wrappers are crude abstractions of the Solaris pre-pthreads mutex API
to POSIX threads.  They are completely useless, complicate audits, and are
mostly unused: there is only one use of any of the pieces of other than
MUTEX_HELD(), and even MUTEX_HELD() has two code paths only one of which
can ever be executed.  All uses of MUTEX_HELD are on pthread locks anyway,
not on the mutex_t wrappers (which are only a typedef for pthread locks
in any case).

Simplify things, drop mutex.h and all its uses, and move to using pthreads
locks everywhere (rather than only almost everywhere).

Signed-off-by: Nick Alcock <nick.alcock at oracle.com>
---
 include/mutex.h     | 30 ------------------------------
 include/port.h      |  5 ++---
 libdtrace/dt_pid.c  |  1 -
 libdtrace/dt_proc.c |  2 --
 libport/time.c      | 10 +---------
 libproc/Pcontrol.c  |  1 -
 libproc/Psymtab.c   |  8 ++++----
 7 files changed, 7 insertions(+), 50 deletions(-)
 delete mode 100644 include/mutex.h

diff --git a/include/mutex.h b/include/mutex.h
deleted file mode 100644
index 2ade826d29638..0000000000000
--- a/include/mutex.h
+++ /dev/null
@@ -1,30 +0,0 @@
-/*
- * Oracle Linux DTrace.
- * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
- * Licensed under the Universal Permissive License v 1.0 as shown at
- * http://oss.oracle.com/licenses/upl.
- */
-
-#ifndef MUTEX_H
-#define MUTEX_H
-#include <pthread.h>
-
-#define mutex_t pthread_mutex_t
-
-#define DEFAULTMUTEX PTHREAD_MUTEX_INITIALIZER
-
-#define mutex_lock(mp)	 	pthread_mutex_lock(mp)
-#define mutex_unlock(mp)	pthread_mutex_unlock(mp)
-#define mutex_destroy(x)	pthread_mutex_destroy(x)
-
-#if defined(HAVE_SEMAPHORE_ATOMIC_COUNT)
-#define mutex_is_locked(x) (atomic_read(&(x)->__data.__count) == 0)
-#else
-#define mutex_is_locked(x) ((x)->__data.__count == 0)
-#endif
-
-#define MUTEX_HELD(x)	mutex_is_locked(x)
-
-extern int mutex_init(mutex_t *, int, void *);
-
-#endif
diff --git a/include/port.h b/include/port.h
index 4b87f4adf91c3..b74a33a988f70 100644
--- a/include/port.h
+++ b/include/port.h
@@ -1,6 +1,6 @@
 /*
  * Oracle Linux DTrace.
- * Copyright (c) 2011, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2011, 2023, Oracle and/or its affiliates. All rights reserved.
  * Licensed under the Universal Permissive License v 1.0 as shown at
  * http://oss.oracle.com/licenses/upl.
  */
@@ -9,7 +9,6 @@
 #define _PORT_H
 
 #include <pthread.h>
-#include <mutex.h>
 #include <unistd.h>
 #include <sys/compiler.h>
 #include <sys/types.h>
@@ -26,7 +25,7 @@ hrtime_t gethrtime(void);
 
 int p_online(int cpun);
 
-int mutex_init(mutex_t *m, int flags1, void *ptr);
+#define MUTEX_HELD(x)	((x)->__data.__count == 0)
 
 int daemonize(int close_fds);
 
diff --git a/libdtrace/dt_pid.c b/libdtrace/dt_pid.c
index b0689aa8a4955..70e0330f6f77b 100644
--- a/libdtrace/dt_pid.c
+++ b/libdtrace/dt_pid.c
@@ -17,7 +17,6 @@
 #include <sys/ioctl.h>
 #include <sys/sysmacros.h>
 
-#include <mutex.h>
 #include <port.h>
 #include <uprobes.h>
 
diff --git a/libdtrace/dt_proc.c b/libdtrace/dt_proc.c
index a3298fdbc68f2..ed142c3bfd46f 100644
--- a/libdtrace/dt_proc.c
+++ b/libdtrace/dt_proc.c
@@ -82,8 +82,6 @@
 #include <poll.h>
 #include <setjmp.h>
 
-#include <mutex.h>
-
 #include <libproc.h>
 #include <dt_proc.h>
 #include <dt_pid.h>
diff --git a/libport/time.c b/libport/time.c
index 120e7357f7325..97f19f04563f9 100644
--- a/libport/time.c
+++ b/libport/time.c
@@ -1,6 +1,6 @@
 /*
  * Oracle Linux DTrace.
- * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2011, 2023, Oracle and/or its affiliates. All rights reserved.
  * Licensed under the Universal Permissive License v 1.0 as shown at
  * http://oss.oracle.com/licenses/upl.
  */
@@ -9,7 +9,6 @@
 #include <sys/dtrace_types.h>
 #include <time.h>
 #include <pthread.h>
-#include <mutex.h>
 
 hrtime_t
 gethrtime(void)
@@ -28,10 +27,3 @@ gethrtime(void)
 
         return v;
 }
-
-int
-mutex_init(mutex_t *m, int flags1, void *ptr)
-{
-	return pthread_mutex_init(m, NULL);
-}
-
diff --git a/libproc/Pcontrol.c b/libproc/Pcontrol.c
index 3d79b638d6196..0cc1692f3b489 100644
--- a/libproc/Pcontrol.c
+++ b/libproc/Pcontrol.c
@@ -31,7 +31,6 @@
 
 #include <dt_debug.h>
 
-#include <mutex.h>
 #include <platform.h>
 #include <port.h>
 
diff --git a/libproc/Psymtab.c b/libproc/Psymtab.c
index a95161884c27a..9191a7ab82c20 100644
--- a/libproc/Psymtab.c
+++ b/libproc/Psymtab.c
@@ -26,7 +26,7 @@
 #include <port.h>
 #include <setjmp.h>
 
-#include <mutex.h>
+#include <pthread.h>
 
 #include <rtld_db.h>
 
@@ -976,7 +976,7 @@ Pmap_mapfile_name(struct ps_prochandle *P, const prmap_t *mapp)
 /*
  * We wouldn't need these if qsort(3C) took an argument for the callback...
  */
-static mutex_t sort_mtx = DEFAULTMUTEX;
+static pthread_mutex_t sort_mtx = PTHREAD_MUTEX_INITIALIZER;
 static char *sort_strs;
 static GElf_Sym *sort_syms;
 
@@ -1175,7 +1175,7 @@ optimize_symtab(sym_tbl_t *symtab)
 	/*
 	 * Sort the two tables according to the appropriate criteria.
 	 */
-	mutex_lock(&sort_mtx);
+	pthread_mutex_lock(&sort_mtx);
 	sort_strs = symtab->sym_strs;
 	sort_syms = syms;
 
@@ -1184,7 +1184,7 @@ optimize_symtab(sym_tbl_t *symtab)
 
 	sort_strs = NULL;
 	sort_syms = NULL;
-	mutex_unlock(&sort_mtx);
+	pthread_mutex_unlock(&sort_mtx);
 
 	free(syms);
 }
-- 
2.42.0.271.g85384428f1