[tip:x86/mm] x86/mm: Redefine some of page table helpers as macros

From: tip-bot for Kirill A. Shutemov
Date: Wed Feb 21 2018 - 06:03:06 EST


Commit-ID: 92e1c5b3f7bf5407cfdbf13613e7101831216dc5
Gitweb: https://git.kernel.org/tip/92e1c5b3f7bf5407cfdbf13613e7101831216dc5
Author: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
AuthorDate: Fri, 16 Feb 2018 14:49:47 +0300
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Wed, 21 Feb 2018 10:19:18 +0100

x86/mm: Redefine some of page table helpers as macros

This is preparation for the next patch, which would change
pgtable_l5_enabled to be cpu_feature_enabled(X86_FEATURE_LA57).

The change makes few helpers in paravirt.h dependent on
cpu_feature_enabled() definition from cpufeature.h.
And cpufeature.h is dependent on paravirt.h.

Let's re-define some of helpers as macros to break this dependency loop.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx>
Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: linux-mm@xxxxxxxxx
Link: http://lkml.kernel.org/r/20180216114948.68868-3-kirill.shutemov@xxxxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/include/asm/paravirt.h | 23 +++++++++++++----------
1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index 3fbaad2..2c0c8c9 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -567,19 +567,22 @@ static inline p4dval_t p4d_val(p4d_t p4d)
return PVOP_CALLEE1(p4dval_t, pv_mmu_ops.p4d_val, p4d.p4d);
}

-static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
+static inline void __set_pgd(pgd_t *pgdp, pgd_t pgd)
{
- if (pgtable_l5_enabled)
- PVOP_VCALL2(pv_mmu_ops.set_pgd, pgdp, native_pgd_val(pgd));
- else
- set_p4d((p4d_t *)(pgdp), (p4d_t) { pgd.pgd });
+ PVOP_VCALL2(pv_mmu_ops.set_pgd, pgdp, native_pgd_val(pgd));
}

-static inline void pgd_clear(pgd_t *pgdp)
-{
- if (pgtable_l5_enabled)
- set_pgd(pgdp, __pgd(0));
-}
+#define set_pgd(pgdp, pgdval) do { \
+ if (pgtable_l5_enabled) \
+ __set_pgd(pgdp, pgdval); \
+ else \
+ set_p4d((p4d_t *)(pgdp), (p4d_t) { (pgdval).pgd }); \
+} while (0)
+
+#define pgd_clear(pgdp) do { \
+ if (pgtable_l5_enabled) \
+ set_pgd(pgdp, __pgd(0)); \
+} while (0)

#endif /* CONFIG_PGTABLE_LEVELS == 5 */