diff --git a/libgomp/Makefile.in b/libgomp/Makefile.in
index 2c81ccacc1dc940b034abac2e2e087151f493b7e..f1afb5ef57f271df537b088d948e8c7416eff6b3 100644
--- a/libgomp/Makefile.in
+++ b/libgomp/Makefile.in
@@ -382,6 +382,7 @@ EXEEXT = @EXEEXT@
FC = @FC@
FCFLAGS = @FCFLAGS@
FGREP = @FGREP@
+FLOCK = @FLOCK@
GREP = @GREP@
INSTALL = @INSTALL@
INSTALL_DATA = @INSTALL_DATA@
diff --git a/libgomp/configure b/libgomp/configure
index fd0e337b5781749279a7a281c2eed87d7c3fd4e2..489c9a00421711d48a3c0a4bbe0cc9809bb6a7a6 100755
--- a/libgomp/configure
+++ b/libgomp/configure
@@ -656,6 +656,7 @@ tmake_file
XLDFLAGS
XCFLAGS
config_path
+FLOCK
CPU_COUNT
LIBGOMP_BUILD_VERSIONED_SHLIB_SUN_FALSE
LIBGOMP_BUILD_VERSIONED_SHLIB_SUN_TRUE
@@ -11418,7 +11419,7 @@ else
lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
lt_status=$lt_dlunknown
cat > conftest.$ac_ext <<_LT_EOF
-#line 11421 "configure"
+#line 11422 "configure"
#include "confdefs.h"
#if HAVE_DLFCN_H
@@ -11524,7 +11525,7 @@ else
lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
lt_status=$lt_dlunknown
cat > conftest.$ac_ext <<_LT_EOF
-#line 11527 "configure"
+#line 11528 "configure"
#include "confdefs.h"
#if HAVE_DLFCN_H
@@ -16486,6 +16487,49 @@ $as_echo "unable to detect (assuming 1)" >&6; }
fi
+for ac_prog in flock
+do
+ # Extract the first word of "$ac_prog", so it can be a program name with args.
+set dummy $ac_prog; ac_word=$2
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+$as_echo_n "checking for $ac_word... " >&6; }
+if ${ac_cv_prog_FLOCK+:} false; then :
+ $as_echo_n "(cached) " >&6
+else
+ if test -n "$FLOCK"; then
+ ac_cv_prog_FLOCK="$FLOCK" # Let the user override the test.
+else
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+for as_dir in $PATH
+do
+ IFS=$as_save_IFS
+ test -z "$as_dir" && as_dir=.
+ for ac_exec_ext in '' $ac_executable_extensions; do
+ if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+ ac_cv_prog_FLOCK="$ac_prog"
+ $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+ break 2
+ fi
+done
+ done
+IFS=$as_save_IFS
+
+fi
+fi
+FLOCK=$ac_cv_prog_FLOCK
+if test -n "$FLOCK"; then
+ { $as_echo "$as_me:${as_lineno-$LINENO}: result: $FLOCK" >&5
+$as_echo "$FLOCK" >&6; }
+else
+ { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+fi
+
+
+ test -n "$FLOCK" && break
+done
+
+
# Get target configury.
. ${srcdir}/configure.tgt
CFLAGS="$save_CFLAGS $XCFLAGS"
diff --git a/libgomp/configure.ac b/libgomp/configure.ac
index a9b1f3973f7b64b8a3e7ba2e2b4abe4f62f35bcf..0fab7168cfac632195beef44e8e7b3c5cf16d71a 100644
--- a/libgomp/configure.ac
+++ b/libgomp/configure.ac
@@ -339,6 +339,8 @@ fi
AX_COUNT_CPUS
AC_SUBST(CPU_COUNT)
+AC_CHECK_PROGS(FLOCK, flock)
+
# Get target configury.
. ${srcdir}/configure.tgt
CFLAGS="$save_CFLAGS $XCFLAGS"
diff --git a/libgomp/testsuite/Makefile.am b/libgomp/testsuite/Makefile.am
index eef02f4a8c25b179e2772e24b1ad22836570e0b2..0cc91ccc4d1fe2ccb538537881e7ba13ca81bf66 100644
--- a/libgomp/testsuite/Makefile.am
+++ b/libgomp/testsuite/Makefile.am
@@ -73,7 +73,8 @@ check_p_numbers4:=$(foreach i,$(check_p_numbers0),$(addprefix $(i),$(check_p_num
check_p_numbers5:=$(addprefix 0,$(check_p_numbers3)) $(check_p_numbers4)
check_p_numbers6:=$(foreach i,$(check_p_numbers0),$(addprefix $(i),$(check_p_numbers5)))
check_p_numbers:=$(check_p_numbers0) $(check_p_numbers2) $(check_p_numbers4) $(check_p_numbers6)
-gcc_test_parallel_slots:=1
+# If unable to serialize execution testing, use just one parallel slot.
+gcc_test_parallel_slots:=$(if $(FLOCK),$(if $(GCC_TEST_PARALLEL_SLOTS),$(GCC_TEST_PARALLEL_SLOTS),19),1)
check_p_subdirs=$(wordlist 1,$(gcc_test_parallel_slots),$(check_p_numbers))
check_DEJAGNU_libgomp_targets = $(addprefix check-DEJAGNUlibgomp,$(check_p_subdirs))
$(check_DEJAGNU_libgomp_targets): check-DEJAGNUlibgomp%: libgomp%/site.exp
diff --git a/libgomp/testsuite/Makefile.in b/libgomp/testsuite/Makefile.in
index 3b5903daed97c8e97a42504b49eac57e96c17fc8..70cb5e42d7bde0e015d7515c7e410fb458d0c29d 100644
--- a/libgomp/testsuite/Makefile.in
+++ b/libgomp/testsuite/Makefile.in
@@ -161,6 +161,7 @@ EXEEXT = @EXEEXT@
FC = @FC@
FCFLAGS = @FCFLAGS@
FGREP = @FGREP@
+FLOCK = @FLOCK@
GREP = @GREP@
INSTALL = @INSTALL@
INSTALL_DATA = @INSTALL_DATA@
@@ -309,7 +310,8 @@ check_p_numbers4 := $(foreach i,$(check_p_numbers0),$(addprefix $(i),$(check_p_n
check_p_numbers5 := $(addprefix 0,$(check_p_numbers3)) $(check_p_numbers4)
check_p_numbers6 := $(foreach i,$(check_p_numbers0),$(addprefix $(i),$(check_p_numbers5)))
check_p_numbers := $(check_p_numbers0) $(check_p_numbers2) $(check_p_numbers4) $(check_p_numbers6)
-gcc_test_parallel_slots := 1
+# If unable to serialize execution testing, use just one parallel slot.
+gcc_test_parallel_slots := $(if $(FLOCK),$(if $(GCC_TEST_PARALLEL_SLOTS),$(GCC_TEST_PARALLEL_SLOTS),19),1)
check_p_subdirs = $(wordlist 1,$(gcc_test_parallel_slots),$(check_p_numbers))
check_DEJAGNU_libgomp_targets = $(addprefix check-DEJAGNUlibgomp,$(check_p_subdirs))
all: all-am
diff --git a/libgomp/testsuite/config/default.exp b/libgomp/testsuite/config/default.exp
index b7afc82ff039ff62da84296df07f00fa697f0014..01569e6ab62668b6b41601c2984e2d6a6592e0bd 100644
--- a/libgomp/testsuite/config/default.exp
+++ b/libgomp/testsuite/config/default.exp
@@ -13,5 +13,3 @@
# You should have received a copy of the GNU General Public License
# along with this program; see the file COPYING3. If not see
# <http://www.gnu.org/licenses/>.
-
-load_lib "standard.exp"
diff --git a/libgomp/testsuite/lib/libgomp.exp b/libgomp/testsuite/lib/libgomp.exp
index 4ea6f26c6748897adac0ab369157a1579bf1f8b1..8512f2c1e64d58f0fe031192712961eef1c9ac12 100644
--- a/libgomp/testsuite/lib/libgomp.exp
+++ b/libgomp/testsuite/lib/libgomp.exp
@@ -9,6 +9,7 @@ proc load_gcc_lib { filename } {
}
load_lib dg.exp
+load_lib standard.exp
# Required to use gcc-dg.exp - however, the latter should NOT be
# loaded until ${tool}_target_compile is defined since it uses that
@@ -297,6 +298,34 @@ proc libgomp_option_proc { option } {
}
}
+if ![info exists ::env(GCC_RUNTEST_PARALLELIZE_DIR)] {
+ # No parallel testing.
+} elseif { $FLOCK == "" } {
+ # Using just one parallel slot.
+} else {
+ # Using several parallel slots. Override DejaGnu
+ # 'standard.exp:${tool}_load'...
+ rename libgomp_load standard_libgomp_load
+ proc libgomp_load { program args } {
+ # ... in order to serialize execution testing via an exclusive lock.
+ set lock_file ../lock
+ set lock_kind --exclusive
+ set lock_fd [open $lock_file a+]
+ set lock_clock_begin [clock seconds]
+ global FLOCK
+ exec $FLOCK $lock_kind 0 <@ $lock_fd
+ set lock_clock_end [clock seconds]
+ verbose -log "Got ${FLOCK}('$lock_file', '$lock_kind') at [clock format $lock_clock_end] after [expr $lock_clock_end - $lock_clock_begin] s" 2
+
+ set result [standard_libgomp_load $program $args]
+
+ # Unlock (implicit with 'close').
+ close $lock_fd
+
+ return $result
+ }
+}
+
# Translate offload target to OpenACC device type. Return the empty string if
# not supported, and 'host' for offload target 'disable'.
proc offload_target_to_openacc_device_type { offload_target } {
diff --git a/libgomp/testsuite/libgomp-site-extra.exp.in b/libgomp/testsuite/libgomp-site-extra.exp.in
index c0d26660bad96f7fcaba6a9073f7fadfff685c0e..0a3ba059c212a3a1b9dfb54eb68e005d68cd32e7 100644
--- a/libgomp/testsuite/libgomp-site-extra.exp.in
+++ b/libgomp/testsuite/libgomp-site-extra.exp.in
@@ -1 +1,2 @@
+set FLOCK {@FLOCK@}
set GCC_UNDER_TEST {@CC@}