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| author |   Paul Burton <paul.burton@mips.com> | 2019-02-02 02:01:02 +0000 |
|---|---|---|
| committer | Paul Burton <paul.burton@mips.com> | 2019-02-04 10:56:48 -0800 |
| commit | 82f4f66ddf11fd4bd2e9b589fd69d0ec6ea777fc (patch) | |
| tree | 661321dc0409e02b9c9b1429f6488b5683eb44e6 /arch | |
| parent | MIPS: MemoryMapID (MMID) Support (diff) | |
| download | linux-dev-82f4f66ddf11fd4bd2e9b589fd69d0ec6ea777fc.tar.xz linux-dev-82f4f66ddf11fd4bd2e9b589fd69d0ec6ea777fc.zip | |
MIPS: Remove open-coded cmpxchg() in set_pte()
set_pte() contains an open coded version of cmpxchg() - it atomically
replaces the buddy pte's value if it is currently zero. Simplify the
code considerably by just using cmpxchg() instead of reinventing it.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/mips/include/asm/pgtable.h | 45 |
1 files changed, 2 insertions, 43 deletions
diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h index 57933fc8fd98..6c13c1d44045 100644 --- a/arch/mips/include/asm/pgtable.h +++ b/arch/mips/include/asm/pgtable.h @@ -17,6 +17,7 @@ #include <asm/pgtable-64.h> #endif +#include <asm/cmpxchg.h> #include <asm/io.h> #include <asm/pgtable-bits.h> @@ -204,49 +205,7 @@ static inline void set_pte(pte_t *ptep, pte_t pteval) * Make sure the buddy is global too (if it's !none, * it better already be global) */ -#ifdef CONFIG_SMP - /* - * For SMP, multiple CPUs can race, so we need to do - * this atomically. - */ - unsigned long page_global = _PAGE_GLOBAL; - unsigned long tmp; - - if (kernel_uses_llsc && R10000_LLSC_WAR) { - __asm__ __volatile__ ( - " .set push \n" - " .set arch=r4000 \n" - " .set noreorder \n" - "1:" __LL "%[tmp], %[buddy] \n" - " bnez %[tmp], 2f \n" - " or %[tmp], %[tmp], %[global] \n" - __SC "%[tmp], %[buddy] \n" - " beqzl %[tmp], 1b \n" - " nop \n" - "2: \n" - " .set pop \n" - : [buddy] "+m" (buddy->pte), [tmp] "=&r" (tmp) - : [global] "r" (page_global)); - } else if (kernel_uses_llsc) { - __asm__ __volatile__ ( - " .set push \n" - " .set "MIPS_ISA_ARCH_LEVEL" \n" - " .set noreorder \n" - "1:" __LL "%[tmp], %[buddy] \n" - " bnez %[tmp], 2f \n" - " or %[tmp], %[tmp], %[global] \n" - __SC "%[tmp], %[buddy] \n" - " beqz %[tmp], 1b \n" - " nop \n" - "2: \n" - " .set pop \n" - : [buddy] "+m" (buddy->pte), [tmp] "=&r" (tmp) - : [global] "r" (page_global)); - } -#else /* !CONFIG_SMP */ - if (pte_none(*buddy)) - pte_val(*buddy) = pte_val(*buddy) | _PAGE_GLOBAL; -#endif /* CONFIG_SMP */ + cmpxchg(&buddy->pte, 0, _PAGE_GLOBAL); } #endif } |