From 5e7700a3f76f91f280b48bca6efa7c09020eb671 Mon Sep 17 00:00:00 2001 From: sunyi <279644543@qq.com> Date: Mon, 6 Jul 2026 17:29:33 +0800 Subject: lib: bitmap: add tests for bitmap_find_next_zero_area_off() Add functional and performance tests for bitmap_find_next_zero_area_off(). performance tests partial output: Start testing find_bit() with random-filled bitmap [ 0.310073] bitmap_find_next_zero_area_off: 852731 ns, 1154 iterations [ 0.311435] find_next_bit: 1356654 ns, 163975 iterations Start testing find_bit() with sparse bitmap [ 0.316267] bitmap_find_next_zero_area_off:4426808 ns, 322479 iterations [ 0.316292] find_next_bit: 15154 ns, 656 iterations Signed-off-by: sunyi <279644543@qq.com> Signed-off-by: Yury Norov --- lib/find_bit_benchmark.c | 17 +++++++++++++++++ lib/test_bitmap.c | 38 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 55 insertions(+) diff --git a/lib/find_bit_benchmark.c b/lib/find_bit_benchmark.c index 00d9dc61cd46..05305e655f99 100644 --- a/lib/find_bit_benchmark.c +++ b/lib/find_bit_benchmark.c @@ -149,6 +149,21 @@ static int __init test_find_next_and_bit(const void *bitmap, return 0; } +static int __init +test_bitmap_find_next_zero_area_off(unsigned long *bitmap, unsigned long len) +{ + unsigned long i, cnt; + ktime_t time; + + time = ktime_get(); + for (cnt = i = 0; i < BITMAP_LEN; cnt++) + i = bitmap_find_next_zero_area_off(bitmap, BITMAP_LEN, i, 8, 0, 0) + 1; + time = ktime_get() - time; + pr_err("bitmap_find_next_zero_area_off:%7llu ns, %6ld iterations\n", time, cnt); + + return 0; +} + static int __init find_bit_test(void) { unsigned long nbits = BITMAP_LEN / SPARSE; @@ -158,6 +173,7 @@ static int __init find_bit_test(void) get_random_bytes(bitmap, sizeof(bitmap)); get_random_bytes(bitmap2, sizeof(bitmap2)); + test_bitmap_find_next_zero_area_off(bitmap, BITMAP_LEN); test_find_next_bit(bitmap, BITMAP_LEN); test_find_next_zero_bit(bitmap, BITMAP_LEN); test_find_last_bit(bitmap, BITMAP_LEN); @@ -181,6 +197,7 @@ static int __init find_bit_test(void) __set_bit(get_random_u32_below(BITMAP_LEN), bitmap2); } + test_bitmap_find_next_zero_area_off(bitmap, BITMAP_LEN); test_find_next_bit(bitmap, BITMAP_LEN); test_find_next_zero_bit(bitmap, BITMAP_LEN); test_find_last_bit(bitmap, BITMAP_LEN); diff --git a/lib/test_bitmap.c b/lib/test_bitmap.c index 69813c10e6c0..8665df77c960 100644 --- a/lib/test_bitmap.c +++ b/lib/test_bitmap.c @@ -234,6 +234,43 @@ static void __init test_find_nth_bit(void) } } +static void __init +test_bitmap_find_next_zero_area_off(void) +{ + DECLARE_BITMAP(bmap, 192); + + bitmap_set(bmap, 0, 192); + + bitmap_clear(bmap, 0, 8); + __clear_bit(50, bmap); + bitmap_clear(bmap, 60, 18); + __set_bit(69, bmap); + __clear_bit(80, bmap); + bitmap_clear(bmap, 100, 10); + __clear_bit(120, bmap); + bitmap_clear(bmap, 145, 8); + bitmap_clear(bmap, 160, 32); + + expect_eq_uint(0, + bitmap_find_next_zero_area_off(bmap, 192, 0, 8, 0, 0)); + expect_eq_uint(0, + bitmap_find_next_zero_area_off(bmap, 192, 0, 8, 3, 0)); + expect_eq_uint(163, + bitmap_find_next_zero_area_off(bmap, 192, 0, 8, 3, 1)); + expect_eq_uint(60, + bitmap_find_next_zero_area_off(bmap, 192, 1, 8, 0, 0)); + expect_eq_uint(160, + bitmap_find_next_zero_area_off(bmap, 192, 1, 8, 7, 0)); + expect_eq_uint(60, + bitmap_find_next_zero_area_off(bmap, 192, 1, 8, 7, 4)); + expect_eq_uint(100, + bitmap_find_next_zero_area_off(bmap, 192, 0, 10, 0, 0)); + expect_eq_uint(160, + bitmap_find_next_zero_area_off(bmap, 192, 0, 32, 0, 0)); + expect_eq_uint(1, + !!(bitmap_find_next_zero_area_off(bmap, 192, 0, 33, 0, 0) >= 192)); +} + static void __init test_fill_set(void) { DECLARE_BITMAP(bmap, 1024); @@ -1559,6 +1596,7 @@ static void __init selftest(void) test_for_each_clear_bitrange_from(); test_for_each_set_clump8(); test_for_each_set_bit_wrap(); + test_bitmap_find_next_zero_area_off(); } KSTM_MODULE_LOADERS(test_bitmap); -- cgit v1.2.3