ARM: 7925/1: mm: keep track of last ASID allocation to improve bitmap searching

[~andy/linux] / arch / arm / mm / context.c

diff --git a/arch/arm/mm/context.c b/arch/arm/mm/context.c
index 3ad0fdaa5cc189e2d061d779059b8ba959f7ece6..52e6f13ac9c78f053acc35e491751869c2895bcd 100644 (file)
--- a/arch/arm/mm/context.c
+++ b/arch/arm/mm/context.c
@@ -180,6 +180,7 @@ static int is_reserved_asid(u64 asid)
 
 static u64 new_context(struct mm_struct *mm, unsigned int cpu)
 {
+       static u32 cur_idx = 1;
        u64 asid = atomic64_read(&mm->context.id);
        u64 generation = atomic64_read(&asid_generation);
 
@@ -197,7 +198,7 @@ static u64 new_context(struct mm_struct *mm, unsigned int cpu)
                 * as we reserve ASID #0 to switch via TTBR0 and indicate
                 * rollover events.
                 */
-               asid = find_next_zero_bit(asid_map, NUM_USER_ASIDS, 1);
+               asid = find_next_zero_bit(asid_map, NUM_USER_ASIDS, cur_idx);
                if (asid == NUM_USER_ASIDS) {
                        generation = atomic64_add_return(ASID_FIRST_VERSION,
                                                         &asid_generation);
@@ -205,6 +206,7 @@ static u64 new_context(struct mm_struct *mm, unsigned int cpu)
                        asid = find_next_zero_bit(asid_map, NUM_USER_ASIDS, 1);
                }
                __set_bit(asid, asid_map);
+               cur_idx = asid;
                asid |= generation;
                cpumask_clear(mm_cpumask(mm));
        }