Perform KABI checks in parallel

Reduce the time required for ./configure to perform the needed
KABI checks by allowing kbuild to compile multiple test cases in
parallel.  This was accomplished by splitting each test's source
code from the logic handling whether that code could be compiled
or not.

By introducing this split it's possible to minimize the number of
times kbuild needs to be invoked.  As importantly, it means all of
the tests can be built in parallel.  This does require a little extra
care since we expect some tests to fail, so the --keep-going (-k)
option must be provided otherwise some tests may not get compiled.
Furthermore, since a failure during the kbuild modpost phase will
result in an early exit; the final linking phase is limited to tests
which passed the initial compilation and produced an object file.

Once everything has been built the configure script proceeds as
previously.  The only significant difference is that it now merely
needs to test for the existence of a .ko file to determine the
result of a given test.  This vastly speeds up the entire process.

New test cases should use ZFS_LINUX_TEST_SRC to declare their test
source code and ZFS_LINUX_TEST_RESULT to check the result.  All of
the existing kernel-*.m4 files have been updated accordingly, see
config/kernel-current-time.m4 for a basic example.  The legacy
ZFS_LINUX_TRY_COMPILE macro has been kept to handle special cases
but it's use is not encouraged.

                  master (secs)   patched (secs)
                  -------------   ----------------
autogen.sh        61              68
configure         137             24  (~17% of current run time)
make -j $(nproc)  44              44
make rpms         287             150

Reviewed-by: Tony Hutter <[email protected]>
Signed-off-by: Brian Behlendorf <[email protected]>
Closes #8547 
Closes #9132
Closes #9341 

1 files changed, 48 insertions, 24 deletions

diff --git a/config/kernel-global_page_state.m4 b/config/kernel-global_page_state.m4
index f4a40011f..a0cb9e2c8 100644
--- a/config/kernel-global_page_state.m4
+++ b/config/kernel-global_page_state.m4
@@ -4,16 +4,21 @@ dnl #
 dnl # 75ef71840539 mm, vmstat: add infrastructure for per-node vmstats
 dnl # 599d0c954f91 mm, vmscan: move LRU lists to node
 dnl #
-AC_DEFUN([ZFS_AC_KERNEL_GLOBAL_NODE_PAGE_STATE], [
-	AC_MSG_CHECKING([whether global_node_page_state() exists])
-	ZFS_LINUX_TRY_COMPILE([
+AC_DEFUN([ZFS_AC_KERNEL_SRC_GLOBAL_NODE_PAGE_STATE], [
+	ZFS_LINUX_TEST_SRC([global_node_page_state], [
 		#include <linux/mm.h>
 		#include <linux/vmstat.h>
 	],[
 		(void) global_node_page_state(0);
-	],[
+	])
+])
+
+AC_DEFUN([ZFS_AC_KERNEL_GLOBAL_NODE_PAGE_STATE], [
+	AC_MSG_CHECKING([whether global_node_page_state() exists])
+	ZFS_LINUX_TEST_RESULT([global_node_page_state], [
 		AC_MSG_RESULT(yes)
-		AC_DEFINE(ZFS_GLOBAL_NODE_PAGE_STATE, 1, [global_node_page_state() exists])
+		AC_DEFINE(ZFS_GLOBAL_NODE_PAGE_STATE, 1,
+		    [global_node_page_state() exists])
 	],[
 		AC_MSG_RESULT(no)
 	])
@@ -24,16 +29,21 @@ dnl # 4.14 API change
 dnl #
 dnl # c41f012ade0b mm: rename global_page_state to global_zone_page_state
 dnl #
-AC_DEFUN([ZFS_AC_KERNEL_GLOBAL_ZONE_PAGE_STATE], [
-	AC_MSG_CHECKING([whether global_zone_page_state() exists])
-	ZFS_LINUX_TRY_COMPILE([
+AC_DEFUN([ZFS_AC_KERNEL_SRC_GLOBAL_ZONE_PAGE_STATE], [
+	ZFS_LINUX_TEST_SRC([global_zone_page_state], [
 		#include <linux/mm.h>
 		#include <linux/vmstat.h>
 	],[
 		(void) global_zone_page_state(0);
-	],[
+	])
+])
+
+AC_DEFUN([ZFS_AC_KERNEL_GLOBAL_ZONE_PAGE_STATE], [
+	AC_MSG_CHECKING([whether global_zone_page_state() exists])
+	ZFS_LINUX_TEST_RESULT([global_zone_page_state], [
 		AC_MSG_RESULT(yes)
-		AC_DEFINE(ZFS_GLOBAL_ZONE_PAGE_STATE, 1, [global_zone_page_state() exists])
+		AC_DEFINE(ZFS_GLOBAL_ZONE_PAGE_STATE, 1,
+		    [global_zone_page_state() exists])
 	],[
 		AC_MSG_RESULT(no)
 	])
@@ -44,9 +54,11 @@ dnl # Create a define and autoconf variable for an enum member
 dnl #
 AC_DEFUN([ZFS_AC_KERNEL_ENUM_MEMBER], [
 	AC_MSG_CHECKING([whether enum $2 contains $1])
-	AS_IF([AC_TRY_COMMAND("${srcdir}/scripts/enum-extract.pl" "$2" "$3" | egrep -qx $1)],[
+	AS_IF([AC_TRY_COMMAND(
+	    "${srcdir}/scripts/enum-extract.pl" "$2" "$3" | egrep -qx $1)],[
 		AC_MSG_RESULT([yes])
-		AC_DEFINE(m4_join([_], [ZFS_ENUM], m4_toupper($2), $1), 1, [enum $2 contains $1])
+		AC_DEFINE(m4_join([_], [ZFS_ENUM], m4_toupper($2), $1), 1,
+		    [enum $2 contains $1])
 		m4_join([_], [ZFS_ENUM], m4_toupper($2), $1)=1
 	],[
 		AC_MSG_RESULT([no])
@@ -59,8 +71,7 @@ dnl #
 AC_DEFUN([ZFS_AC_KERNEL_GLOBAL_PAGE_STATE_ENUM_ERROR],[
 	AC_MSG_RESULT(no)
 	AC_MSG_RESULT([$1 in either node_stat_item or zone_stat_item: $2])
-	AC_MSG_RESULT([configure needs updating, see: config/kernel-global_page_state.m4])
-	AC_MSG_FAILURE([SHUT 'ER DOWN CLANCY, SHE'S PUMPIN' MUD!])
+	ZFS_LINUX_TEST_ERROR([global page state])
 ])
 
 AC_DEFUN([ZFS_AC_KERNEL_GLOBAL_PAGE_STATE_ENUM_CHECK], [
@@ -75,10 +86,10 @@ AC_DEFUN([ZFS_AC_KERNEL_GLOBAL_PAGE_STATE_ENUM_CHECK], [
 ])
 
 dnl #
-dnl # Ensure the config tests are finding one and only one of each enum of interest
+dnl # Ensure the config tests are finding one and only one of each enum.
 dnl #
 AC_DEFUN([ZFS_AC_KERNEL_GLOBAL_ZONE_PAGE_STATE_SANITY], [
-	AC_MSG_CHECKING([global_page_state enums are sane])
+	AC_MSG_CHECKING([whether global_page_state enums are sane])
 
 	ZFS_AC_KERNEL_GLOBAL_PAGE_STATE_ENUM_CHECK([NR_FILE_PAGES])
 	ZFS_AC_KERNEL_GLOBAL_PAGE_STATE_ENUM_CHECK([NR_INACTIVE_ANON])
@@ -88,6 +99,11 @@ AC_DEFUN([ZFS_AC_KERNEL_GLOBAL_ZONE_PAGE_STATE_SANITY], [
 	AC_MSG_RESULT(yes)
 ])
 
+AC_DEFUN([ZFS_AC_KERNEL_SRC_GLOBAL_PAGE_STATE], [
+	ZFS_AC_KERNEL_SRC_GLOBAL_NODE_PAGE_STATE
+	ZFS_AC_KERNEL_SRC_GLOBAL_ZONE_PAGE_STATE
+])
+
 dnl #
 dnl # enum members in which we're interested
 dnl #
@@ -95,15 +111,23 @@ AC_DEFUN([ZFS_AC_KERNEL_GLOBAL_PAGE_STATE], [
 	ZFS_AC_KERNEL_GLOBAL_NODE_PAGE_STATE
 	ZFS_AC_KERNEL_GLOBAL_ZONE_PAGE_STATE
 
-	ZFS_AC_KERNEL_ENUM_MEMBER([NR_FILE_PAGES],		[node_stat_item], [$LINUX/include/linux/mmzone.h])
-	ZFS_AC_KERNEL_ENUM_MEMBER([NR_INACTIVE_ANON],		[node_stat_item], [$LINUX/include/linux/mmzone.h])
-	ZFS_AC_KERNEL_ENUM_MEMBER([NR_INACTIVE_FILE],		[node_stat_item], [$LINUX/include/linux/mmzone.h])
-	ZFS_AC_KERNEL_ENUM_MEMBER([NR_SLAB_RECLAIMABLE],	[node_stat_item], [$LINUX/include/linux/mmzone.h])
+	ZFS_AC_KERNEL_ENUM_MEMBER([NR_FILE_PAGES],
+	    [node_stat_item], [$LINUX/include/linux/mmzone.h])
+	ZFS_AC_KERNEL_ENUM_MEMBER([NR_INACTIVE_ANON],
+	    [node_stat_item], [$LINUX/include/linux/mmzone.h])
+	ZFS_AC_KERNEL_ENUM_MEMBER([NR_INACTIVE_FILE],
+	    [node_stat_item], [$LINUX/include/linux/mmzone.h])
+	ZFS_AC_KERNEL_ENUM_MEMBER([NR_SLAB_RECLAIMABLE],
+	    [node_stat_item], [$LINUX/include/linux/mmzone.h])
 
-	ZFS_AC_KERNEL_ENUM_MEMBER([NR_FILE_PAGES],		[zone_stat_item], [$LINUX/include/linux/mmzone.h])
-	ZFS_AC_KERNEL_ENUM_MEMBER([NR_INACTIVE_ANON],		[zone_stat_item], [$LINUX/include/linux/mmzone.h])
-	ZFS_AC_KERNEL_ENUM_MEMBER([NR_INACTIVE_FILE],		[zone_stat_item], [$LINUX/include/linux/mmzone.h])
-	ZFS_AC_KERNEL_ENUM_MEMBER([NR_SLAB_RECLAIMABLE],	[zone_stat_item], [$LINUX/include/linux/mmzone.h])
+	ZFS_AC_KERNEL_ENUM_MEMBER([NR_FILE_PAGES],
+	    [zone_stat_item], [$LINUX/include/linux/mmzone.h])
+	ZFS_AC_KERNEL_ENUM_MEMBER([NR_INACTIVE_ANON],
+	    [zone_stat_item], [$LINUX/include/linux/mmzone.h])
+	ZFS_AC_KERNEL_ENUM_MEMBER([NR_INACTIVE_FILE],
+	    [zone_stat_item], [$LINUX/include/linux/mmzone.h])
+	ZFS_AC_KERNEL_ENUM_MEMBER([NR_SLAB_RECLAIMABLE],
+	    [zone_stat_item], [$LINUX/include/linux/mmzone.h])
 
 	ZFS_AC_KERNEL_GLOBAL_ZONE_PAGE_STATE_SANITY
 ])