mmc: mmc_test: add tests to measure large sequential I/O performance

Add two large sequential I/O performance tests:
        35. Large sequential read into scattered pages
        36. Large sequential write from scattered pages

The tests measure transfer times for 10MiB, 100MiB, 1000MiB.
Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

drivers/mmc/card/mmc_test.c

@@ -1871,6 +1871,92 @@ static int mmc_test_random_write_perf(struct mmc_test_card *test)
 	return mmc_test_random_perf(test, 1);
 }
 
+static int mmc_test_seq_perf(struct mmc_test_card *test, int write,
+			     unsigned int tot_sz, int max_scatter)
+{
+	unsigned int dev_addr, i, cnt, sz, ssz;
+	struct timespec ts1, ts2, ts;
+	int ret;
+
+	sz = test->area.max_tfr;
+	/*
+	 * In the case of a maximally scattered transfer, the maximum transfer
+	 * size is further limited by using PAGE_SIZE segments.
+	 */
+	if (max_scatter) {
+		struct mmc_test_area *t = &test->area;
+		unsigned long max_tfr;
+
+		if (t->max_seg_sz >= PAGE_SIZE)
+			max_tfr = t->max_segs * PAGE_SIZE;
+		else
+			max_tfr = t->max_segs * t->max_seg_sz;
+		if (sz > max_tfr)
+			sz = max_tfr;
+	}
+
+	ssz = sz >> 9;
+	dev_addr = mmc_test_capacity(test->card) / 4;
+	if (tot_sz > dev_addr << 9)
+		tot_sz = dev_addr << 9;
+	cnt = tot_sz / sz;
+	dev_addr &= 0xffff0000; /* Round to 64MiB boundary */
+
+	getnstimeofday(&ts1);
+	for (i = 0; i < cnt; i++) {
+		ret = mmc_test_area_io(test, sz, dev_addr, write,
+				       max_scatter, 0);
+		if (ret)
+			return ret;
+		dev_addr += ssz;
+	}
+	getnstimeofday(&ts2);
+
+	ts = timespec_sub(ts2, ts1);
+	mmc_test_print_avg_rate(test, sz, cnt, &ts1, &ts2);
+
+	return 0;
+}
+
+static int mmc_test_large_seq_perf(struct mmc_test_card *test, int write)
+{
+	int ret, i;
+
+	for (i = 0; i < 10; i++) {
+		ret = mmc_test_seq_perf(test, write, 10 * 1024 * 1024, 1);
+		if (ret)
+			return ret;
+	}
+	for (i = 0; i < 5; i++) {
+		ret = mmc_test_seq_perf(test, write, 100 * 1024 * 1024, 1);
+		if (ret)
+			return ret;
+	}
+	for (i = 0; i < 3; i++) {
+		ret = mmc_test_seq_perf(test, write, 1000 * 1024 * 1024, 1);
+		if (ret)
+			return ret;
+	}
+
+	return ret;
+}
+
+/*
+ * Large sequential read performance.
+ */
+static int mmc_test_large_seq_read_perf(struct mmc_test_card *test)
+{
+	return mmc_test_large_seq_perf(test, 0);
+}
+
+/*
+ * Large sequential write performance.
+ */
+static int mmc_test_large_seq_write_perf(struct mmc_test_card *test)
+{
+	return mmc_test_large_seq_perf(test, 1);
+}
+
 static const struct mmc_test_case mmc_test_cases[] = {
 	{
 		.name = "Basic write (no data verification)",
@@ -2124,6 +2210,20 @@ static const struct mmc_test_case mmc_test_cases[] = {
 		.cleanup = mmc_test_area_cleanup,
 	},
 
+	{
+		.name = "Large sequential read into scattered pages",
+		.prepare = mmc_test_area_prepare,
+		.run = mmc_test_large_seq_read_perf,
+		.cleanup = mmc_test_area_cleanup,
+	},
+
+	{
+		.name = "Large sequential write from scattered pages",
+		.prepare = mmc_test_area_prepare,
+		.run = mmc_test_large_seq_write_perf,
+		.cleanup = mmc_test_area_cleanup,
+	},
+
 };
 
 static DEFINE_MUTEX(mmc_test_lock);