diff options
Diffstat (limited to 'pixman/test/lowlevel-blt-bench.c')
| -rw-r--r-- | pixman/test/lowlevel-blt-bench.c | 31 |
1 files changed, 25 insertions, 6 deletions
diff --git a/pixman/test/lowlevel-blt-bench.c b/pixman/test/lowlevel-blt-bench.c index 7336fa0d5..8e80b4280 100644 --- a/pixman/test/lowlevel-blt-bench.c +++ b/pixman/test/lowlevel-blt-bench.c @@ -33,6 +33,14 @@ #define L1CACHE_SIZE (8 * 1024) #define L2CACHE_SIZE (128 * 1024) +/* This is applied to both L1 and L2 tests - alternatively, you could + * parameterise bench_L or split it into two functions. It could be + * read at runtime on some architectures, but it only really matters + * that it's a number that's an integer divisor of both cacheline + * lengths, and further, it only really matters for caches that don't + * do allocate0on-write. */ +#define CACHELINE_LENGTH (32) /* bytes */ + #define WIDTH 1920 #define HEIGHT 1080 #define BUFSIZE (WIDTH * HEIGHT * 4) @@ -168,18 +176,29 @@ bench_L (pixman_op_t op, int width, int lines_count) { - int64_t i, j; + int64_t i, j, k; int x = 0; int q = 0; volatile int qx; for (i = 0; i < n; i++) { - /* touch destination buffer to fetch it into L1 cache */ - for (j = 0; j < width + 64; j += 16) { - q += dst[j]; - q += src[j]; - } + /* For caches without allocate-on-write, we need to force the + * destination buffer back into the cache on each iteration, + * otherwise if they are evicted during the test, they remain + * uncached. This doesn't matter for tests which read the + * destination buffer, or for caches that do allocate-on-write, + * but in those cases this loop just adds constant time, which + * should be successfully cancelled out. + */ + for (j = 0; j < lines_count; j++) + { + for (k = 0; k < width + 62; k += CACHELINE_LENGTH / sizeof *dst) + { + q += dst[j * WIDTH + k]; + } + q += dst[j * WIDTH + width + 62]; + } if (++x >= 64) x = 0; call_func (func, op, src_img, mask_img, dst_img, x, 0, x, 0, 63 - x, 0, width, lines_count); |