summaryrefslogtreecommitdiff
path: root/arch/loongarch/include/asm/pgtable.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/loongarch/include/asm/pgtable.h')
-rw-r--r--arch/loongarch/include/asm/pgtable.h21
1 files changed, 21 insertions, 0 deletions
diff --git a/arch/loongarch/include/asm/pgtable.h b/arch/loongarch/include/asm/pgtable.h
index 8920dd8b297b..5e33987d0a13 100644
--- a/arch/loongarch/include/asm/pgtable.h
+++ b/arch/loongarch/include/asm/pgtable.h
@@ -279,8 +279,29 @@ 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;
+
+ __asm__ __volatile__ (
+ "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"
+ __WEAK_LLSC_MB
+ : [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 */
}
}