Commit 86727443 authored by Dan Williams's avatar Dan Williams
Browse files

dmatest: add basic performance metrics 



Add iops and throughput to the summary output.

Acked-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent e3b9c347

Documentation/dmatest.txt

+4 −0
Original line number Diff line number Diff line
@@ -77,5 +77,9 @@ the parens represents additional information, e.g. error code, error counter, 
or status.  A test thread also emits a summary line at completion listing the

number of tests executed, number that failed, and a result code.



Example:

	% dmesg | tail -n 1

	dmatest: dma3chan0-copy0: summary 400000 tests, 0 failures iops: 61524 KB/s 246098 (0)



The details of a data miscompare error are also emitted, but do not follow the

above format.

drivers/dma/dmatest.c

+33 −2
Original line number Diff line number Diff line
@@ -325,6 +325,29 @@ static void dbg_result(const char *err, unsigned int n, unsigned int src_off, 
		 current->comm, n, err, src_off, dst_off, len, data);

}



static unsigned long long dmatest_persec(s64 runtime, unsigned int val)

{

	unsigned long long per_sec = 1000000;



	if (runtime <= 0)

		return 0;



	/* drop precision until runtime is 32-bits */

	while (runtime > UINT_MAX) {

		runtime >>= 1;

		per_sec <<= 1;

	}



	per_sec *= val;

	do_div(per_sec, runtime);

	return per_sec;

}



static unsigned long long dmatest_KBs(s64 runtime, unsigned long long len)

{

	return dmatest_persec(runtime, len >> 10);

}



/*

 * This function repeatedly tests DMA transfers of various lengths and

 * offsets for a given operation type until it is told to exit by
@@ -360,6 +383,9 @@ static int dmatest_func(void *data) 
	int			src_cnt;

	int			dst_cnt;

	int			i;

	ktime_t			ktime;

	s64			runtime = 0;

	unsigned long long	total_len = 0;



	set_freezable();
@@ -417,6 +443,7 @@ static int dmatest_func(void *data) 
	 */

	flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;



	ktime = ktime_get();

	while (!kthread_should_stop()

	       && !(params->iterations && total_tests >= params->iterations)) {

		struct dma_async_tx_descriptor *tx = NULL;
@@ -464,6 +491,7 @@ static int dmatest_func(void *data) 
		len = (len >> align) << align;

		if (!len)

			len = 1 << align;

		total_len += len;



		for (i = 0; i < src_cnt; i++) {

			u8 *buf = thread->srcs[i] + src_off;
@@ -607,6 +635,7 @@ static int dmatest_func(void *data) 
				   len, 0);

		}

	}

	runtime = ktime_us_delta(ktime_get(), ktime);



	ret = 0;

	for (i = 0; thread->dsts[i]; i++)
@@ -621,8 +650,10 @@ static int dmatest_func(void *data) 
err_srcs:

	kfree(pq_coefs);

err_thread_type:

	pr_info("%s: terminating after %u tests, %u failures (status %d)\n",

		current->comm, total_tests, failed_tests, ret);

	pr_info("%s: summary %u tests, %u failures %llu iops %llu KB/s (%d)\n",

		current->comm, total_tests, failed_tests,

		dmatest_persec(runtime, total_tests),

		dmatest_KBs(runtime, total_len), ret);



	/* terminate all transfers on specified channels */

	if (ret)