kernel_fpu fixes

This patch fixes a few issues when detecting which kernel_fpu functions
are available.

- Use kernel_fpu_begin() if it's exported on newer kernels.

- Use ZFS_LINUX_TRY_COMPILE_SYMBOL() to choose the right kernel_fpu
  function when using --enable-linux-builtin.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes #8259
Closes #8363

diff --git a/config/kernel-fpu.m4 b/config/kernel-fpu.m4
index 671fe7ea54e8c2bd45476616690add3194a4a8e6..5fff79a74c708c34ef0231597717b0c5dee6472e 100644 (file)
--- a/config/kernel-fpu.m4
+++ b/config/kernel-fpu.m4
@@ -12,25 +12,49 @@ dnl # Pre-4.2:      Use kernel_fpu_{begin,end}()
 dnl #          HAVE_KERNEL_FPU & KERNEL_EXPORTS_X86_FPU
 dnl #
 AC_DEFUN([ZFS_AC_KERNEL_FPU], [
-       AC_MSG_CHECKING([which kernel_fpu function to use])
+       AC_MSG_CHECKING([which kernel_fpu header to use])
        ZFS_LINUX_TRY_COMPILE([
+               #include <linux/module.h>
+               #include <asm/fpu/api.h>
+       ],[
+       ],[
+               AC_DEFINE(HAVE_KERNEL_FPU_API_HEADER, 1, [kernel has asm/fpu/api.h])
+               AC_MSG_RESULT(asm/fpu/api.h)
+       ],[
+               AC_MSG_RESULT(i387.h & xcr.h)
+       ])
+
+       AC_MSG_CHECKING([which kernel_fpu function to use])
+       ZFS_LINUX_TRY_COMPILE_SYMBOL([
+               #include <linux/module.h>
+               #ifdef HAVE_KERNEL_FPU_API_HEADER
+               #include <asm/fpu/api.h>
+               #else
                #include <asm/i387.h>
                #include <asm/xcr.h>
+               #endif
+               MODULE_LICENSE("$ZFS_META_LICENSE");
        ],[
                kernel_fpu_begin();
                kernel_fpu_end();
-       ],[
+       ], [kernel_fpu_begin], [arch/x86/kernel/fpu/core.c], [
                AC_MSG_RESULT(kernel_fpu_*)
                AC_DEFINE(HAVE_KERNEL_FPU, 1, [kernel has kernel_fpu_* functions])
                AC_DEFINE(KERNEL_EXPORTS_X86_FPU, 1, [kernel exports FPU functions])
        ],[
-               ZFS_LINUX_TRY_COMPILE([
-                       #include <linux/kernel.h>
+               ZFS_LINUX_TRY_COMPILE_SYMBOL([
+                       #include <linux/module.h>
+                       #ifdef HAVE_KERNEL_FPU_API_HEADER
                        #include <asm/fpu/api.h>
+                       #else
+                       #include <asm/i387.h>
+                       #include <asm/xcr.h>
+                       #endif
+                       MODULE_LICENSE("$ZFS_META_LICENSE");
                ],[
                        __kernel_fpu_begin();
                        __kernel_fpu_end();
-               ],[
+               ], [__kernel_fpu_begin], [arch/x86/kernel/fpu/core.c arch/x86/kernel/i387.c], [
                        AC_MSG_RESULT(__kernel_fpu_*)
                        AC_DEFINE(HAVE_UNDERSCORE_KERNEL_FPU, 1, [kernel has __kernel_fpu_* functions])
                        AC_DEFINE(KERNEL_EXPORTS_X86_FPU, 1, [kernel exports FPU functions])

diff --git a/include/linux/simd_x86.h b/include/linux/simd_x86.h
index 5d6fbed35b9fd110d16a8c62c0efb8f762c54857..12cd7467788eb174af5437edf25458c2f349077b 100644 (file)
--- a/include/linux/simd_x86.h
+++ b/include/linux/simd_x86.h
@@ -81,9 +81,16 @@
 #endif
 
 #if defined(_KERNEL)
-#if defined(HAVE_UNDERSCORE_KERNEL_FPU)
+
+#if defined(HAVE_KERNEL_FPU_API_HEADER)
 #include <asm/fpu/api.h>
 #include <asm/fpu/internal.h>
+#else
+#include <asm/i387.h>
+#include <asm/xcr.h>
+#endif
+
+#if defined(HAVE_UNDERSCORE_KERNEL_FPU)
 #define        kfpu_begin()            \
 {                                                      \
        preempt_disable();              \
@@ -95,8 +102,6 @@
        preempt_enable();               \
 }
 #elif defined(HAVE_KERNEL_FPU)
-#include <asm/i387.h>
-#include <asm/xcr.h>
 #define        kfpu_begin()    kernel_fpu_begin()
 #define        kfpu_end()              kernel_fpu_end()
 #else