lkml.org 
[lkml]   [2020]   [Nov]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v1 3/3] powerpc/32s: Cleanup around PTE_FLAGS_OFFSET in hash_low.S
Date
PTE_FLAGS_OFFSET is defined in asm/page_32.h and used only
in hash_low.S

And PTE_FLAGS_OFFSET nullity depends on CONFIG_PTE_64BIT

Instead of tests like #if (PTE_FLAGS_OFFSET != 0), use
CONFIG_PTE_64BIT related code.

Also move the definition of PTE_FLAGS_OFFSET into hash_low.S
directly, that improves readability.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/include/asm/page_32.h | 6 ------
arch/powerpc/mm/book3s32/hash_low.S | 23 +++++++++++++----------
2 files changed, 13 insertions(+), 16 deletions(-)

diff --git a/arch/powerpc/include/asm/page_32.h b/arch/powerpc/include/asm/page_32.h
index d64dfe3ac712..56f217606327 100644
--- a/arch/powerpc/include/asm/page_32.h
+++ b/arch/powerpc/include/asm/page_32.h
@@ -16,12 +16,6 @@
#define ARCH_DMA_MINALIGN L1_CACHE_BYTES
#endif

-#ifdef CONFIG_PTE_64BIT
-#define PTE_FLAGS_OFFSET 4 /* offset of PTE flags, in bytes */
-#else
-#define PTE_FLAGS_OFFSET 0
-#endif
-
#if defined(CONFIG_PPC_256K_PAGES) || \
(defined(CONFIG_PPC_8xx) && defined(CONFIG_PPC_16K_PAGES))
#define PTE_SHIFT (PAGE_SHIFT - PTE_T_LOG2 - 2) /* 1/4 of a page */
diff --git a/arch/powerpc/mm/book3s32/hash_low.S b/arch/powerpc/mm/book3s32/hash_low.S
index 1366e8e4fc05..f559a931b9a8 100644
--- a/arch/powerpc/mm/book3s32/hash_low.S
+++ b/arch/powerpc/mm/book3s32/hash_low.S
@@ -26,6 +26,12 @@
#include <asm/feature-fixups.h>
#include <asm/code-patching-asm.h>

+#ifdef CONFIG_PTE_64BIT
+#define PTE_FLAGS_OFFSET 4 /* offset of PTE flags, in bytes */
+#else
+#define PTE_FLAGS_OFFSET 0
+#endif
+
#ifdef CONFIG_SMP
.section .bss
.align 2
@@ -94,6 +100,11 @@ _GLOBAL(hash_page)
rlwimi r8,r4,22,20,29 /* insert next 10 bits of address */
#else
rlwimi r8,r4,23,20,28 /* compute pte address */
+ /*
+ * If PTE_64BIT is set, the low word is the flags word; use that
+ * word for locking since it contains all the interesting bits.
+ */
+ addi r8,r8,PTE_FLAGS_OFFSET
#endif

/*
@@ -101,13 +112,7 @@ _GLOBAL(hash_page)
* because almost always, there won't be a permission violation
* and there won't already be an HPTE, and thus we will have
* to update the PTE to set _PAGE_HASHPTE. -- paulus.
- *
- * If PTE_64BIT is set, the low word is the flags word; use that
- * word for locking since it contains all the interesting bits.
*/
-#if (PTE_FLAGS_OFFSET != 0)
- addi r8,r8,PTE_FLAGS_OFFSET
-#endif
.Lretry:
lwarx r6,0,r8 /* get linux-style pte, flag word */
#ifdef CONFIG_PPC_KUAP
@@ -511,8 +516,9 @@ _GLOBAL(flush_hash_pages)
rlwimi r5,r4,22,20,29
#else
rlwimi r5,r4,23,20,28
+ addi r5,r5,PTE_FLAGS_OFFSET
#endif
-1: lwz r0,PTE_FLAGS_OFFSET(r5)
+1: lwz r0,0(r5)
cmpwi cr1,r6,1
andi. r0,r0,_PAGE_HASHPTE
bne 2f
@@ -556,9 +562,6 @@ _GLOBAL(flush_hash_pages)
* already clear, we're done (for this pte). If not,
* clear it (atomically) and proceed. -- paulus.
*/
-#if (PTE_FLAGS_OFFSET != 0)
- addi r5,r5,PTE_FLAGS_OFFSET
-#endif
33: lwarx r8,0,r5 /* fetch the pte flags word */
andi. r0,r8,_PAGE_HASHPTE
beq 8f /* done if HASHPTE is already clear */
--
2.25.0
\
 
 \ /
  Last update: 2020-11-24 20:53    [W:0.130 / U:0.168 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site