Linux 3.12 compat: New shrinker API

[mirror_spl.git] / config / spl-build.m4

diff --git a/config/spl-build.m4 b/config/spl-build.m4
index b0e334815bbfe3e5491228d168e32444e750ef68..7d744db1370f4bc890780022696a8d08981703c3 100644 (file)
--- a/config/spl-build.m4
+++ b/config/spl-build.m4
@@ -27,8 +27,7 @@ AC_DEFUN([SPL_AC_CONFIG_KERNEL], [
        SPL_AC_TYPE_ATOMIC64_XCHG
        SPL_AC_TYPE_UINTPTR_T
        SPL_AC_2ARGS_REGISTER_SYSCTL
-       SPL_AC_SET_SHRINKER
-       SPL_AC_3ARGS_SHRINKER_CALLBACK
+       SPL_AC_SHRINKER_CALLBACK
        SPL_AC_PATH_IN_NAMEIDATA
        SPL_AC_TASK_CURR
        SPL_AC_CTL_UNNUMBERED
@@ -885,37 +884,18 @@ AC_DEFUN([SPL_AC_2ARGS_REGISTER_SYSCTL],
        ])
 ])
 
-dnl #
-dnl # 2.6.23 API change
-dnl # Old set_shrinker API replaced with register_shrinker
-dnl #
-AC_DEFUN([SPL_AC_SET_SHRINKER], [
-       AC_MSG_CHECKING([whether set_shrinker() available])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/mm.h>
-       ],[
-               return set_shrinker(DEFAULT_SEEKS, NULL);
-       ],[
-               AC_MSG_RESULT([yes])
-               AC_DEFINE(HAVE_SET_SHRINKER, 1,
-                         [set_shrinker() available])
-       ],[
-               AC_MSG_RESULT([no])
-       ])
-])
-
-dnl #
-dnl # 2.6.35 API change,
-dnl # Add context to shrinker callback
-dnl #
-AC_DEFUN([SPL_AC_3ARGS_SHRINKER_CALLBACK],
-       [AC_MSG_CHECKING([whether shrinker callback wants 3 args])
+AC_DEFUN([SPL_AC_SHRINKER_CALLBACK],[
        tmp_flags="$EXTRA_KCFLAGS"
        EXTRA_KCFLAGS="-Werror"
+       dnl #
+       dnl # 2.6.23 to 2.6.34 API change
+       dnl # ->shrink(int nr_to_scan, gfp_t gfp_mask)
+       dnl #
+       AC_MSG_CHECKING([whether old 2-argument shrinker exists])
        SPL_LINUX_TRY_COMPILE([
                #include <linux/mm.h>
 
-               int shrinker_cb(struct shrinker *, int, unsigned int);
+               int shrinker_cb(int nr_to_scan, gfp_t gfp_mask);
        ],[
                struct shrinker cache_shrinker = {
                        .shrink = shrinker_cb,
@@ -924,10 +904,86 @@ AC_DEFUN([SPL_AC_3ARGS_SHRINKER_CALLBACK],
                register_shrinker(&cache_shrinker);
        ],[
                AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_3ARGS_SHRINKER_CALLBACK, 1,
-                         [shrinker callback wants 3 args])
+               AC_DEFINE(HAVE_2ARGS_OLD_SHRINKER_CALLBACK, 1,
+                       [old shrinker callback wants 2 args])
        ],[
                AC_MSG_RESULT(no)
+               dnl #
+               dnl # 2.6.35 - 2.6.39 API change
+               dnl # ->shrink(struct shrinker *,
+               dnl #          int nr_to_scan, gfp_t gfp_mask)
+               dnl #
+               AC_MSG_CHECKING([whether old 3-argument shrinker exists])
+               SPL_LINUX_TRY_COMPILE([
+                       #include <linux/mm.h>
+
+                       int shrinker_cb(struct shrinker *, int nr_to_scan,
+                                       gfp_t gfp_mask);
+               ],[
+                       struct shrinker cache_shrinker = {
+                               .shrink = shrinker_cb,
+                               .seeks = DEFAULT_SEEKS,
+                       };
+                       register_shrinker(&cache_shrinker);
+               ],[
+                       AC_MSG_RESULT(yes)
+                       AC_DEFINE(HAVE_3ARGS_SHRINKER_CALLBACK, 1,
+                               [old shrinker callback wants 3 args])
+               ],[
+                       AC_MSG_RESULT(no)
+                       dnl #
+                       dnl # 3.0 - 3.11 API change
+                       dnl # ->shrink(struct shrinker *,
+                       dnl #          struct shrink_control *sc)
+                       dnl #
+                       AC_MSG_CHECKING(
+                               [whether new 2-argument shrinker exists])
+                       SPL_LINUX_TRY_COMPILE([
+                               #include <linux/mm.h>
+
+                               int shrinker_cb(struct shrinker *,
+                                               struct shrink_control *sc);
+                       ],[
+                               struct shrinker cache_shrinker = {
+                                       .shrink = shrinker_cb,
+                                       .seeks = DEFAULT_SEEKS,
+                               };
+                               register_shrinker(&cache_shrinker);
+                       ],[
+                               AC_MSG_RESULT(yes)
+                               AC_DEFINE(HAVE_2ARGS_NEW_SHRINKER_CALLBACK, 1,
+                                       [new shrinker callback wants 2 args])
+                       ],[
+                               AC_MSG_RESULT(no)
+                               dnl #
+                               dnl # 3.12 API change,
+                               dnl # ->shrink() is logically split in to
+                               dnl # ->count_objects() and ->scan_objects()
+                               dnl #
+                               AC_MSG_CHECKING(
+                                   [whether ->count_objects callback exists])
+                               SPL_LINUX_TRY_COMPILE([
+                                       #include <linux/mm.h>
+
+                                       unsigned long shrinker_cb(
+                                               struct shrinker *,
+                                               struct shrink_control *sc);
+                               ],[
+                                       struct shrinker cache_shrinker = {
+                                               .count_objects = shrinker_cb,
+                                               .scan_objects = shrinker_cb,
+                                               .seeks = DEFAULT_SEEKS,
+                                       };
+                                       register_shrinker(&cache_shrinker);
+                               ],[
+                                       AC_MSG_RESULT(yes)
+                                       AC_DEFINE(HAVE_SPLIT_SHRINKER_CALLBACK,
+                                               1, [->count_objects exists])
+                               ],[
+                                       AC_MSG_ERROR(error)
+                               ])
+                       ])
+               ])
        ])
        EXTRA_KCFLAGS="$tmp_flags"
 ])