[PATCH 2/3] x86/mm: Redefine some of page table helpers as macros

From: Kirill A. Shutemov
Date: Fri Feb 16 2018 - 06:50:04 EST


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>
---
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 70d3c86927de..6d3b921ae43a 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 */

--
2.15.1