diff mbox series

[PATCHv3,07/10] lib: add crc64 tests

Message ID 20220222163144.1782447-8-kbusch@kernel.org (mailing list archive)
State Not Applicable
Delegated to: Herbert Xu
Headers show
Series 64-bit data integrity field support | expand

Commit Message

Keith Busch Feb. 22, 2022, 4:31 p.m. UTC 
Provide a module to test the rocksoft crc64 calculations with well known
inputs and exepected values. Check the generic table implementation and
whatever module is registered from the crypto library, and compare their
speeds.

Signed-off-by: Keith Busch <kbusch@kernel.org>
---
 lib/Kconfig.debug |   4 ++
 lib/Makefile      |   1 +
 lib/test_crc64.c  | 133 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 138 insertions(+)
 create mode 100644 lib/test_crc64.c

Comments

Chaitanya Kulkarni Feb. 22, 2022, 4:50 p.m. UTC | #1 
On 2/22/22 08:31, Keith Busch wrote:
> Provide a module to test the rocksoft crc64 calculations with well known
> inputs and exepected values. Check the generic table implementation and
> whatever module is registered from the crypto library, and compare their
> speeds.
> 
> Signed-off-by: Keith Busch <kbusch@kernel.org>
> ---

Looks good.

Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>

-ck
Christoph Hellwig Feb. 25, 2022, 4:05 p.m. UTC | #2 
On Tue, Feb 22, 2022 at 08:31:41AM -0800, Keith Busch wrote:
> Provide a module to test the rocksoft crc64 calculations with well known
> inputs and exepected values. Check the generic table implementation and
> whatever module is registered from the crypto library, and compare their
> speeds.

The code looks good, but isn't the trent to use the kunit framework
for these kinds of tests these days?
Keith Busch Feb. 25, 2022, 4:12 p.m. UTC | #3 
On Fri, Feb 25, 2022 at 05:05:09PM +0100, Christoph Hellwig wrote:
> On Tue, Feb 22, 2022 at 08:31:41AM -0800, Keith Busch wrote:
> > Provide a module to test the rocksoft crc64 calculations with well known
> > inputs and exepected values. Check the generic table implementation and
> > whatever module is registered from the crypto library, and compare their
> > speeds.
> 
> The code looks good, but isn't the trent to use the kunit framework
> for these kinds of tests these days?

I don't have experience with kunit, but I'll look into that.

I am already changing the way this gets tested. Eric recommended adding
to the crypto "testmgr", and I've done that on my private tree. That
test framework exercises a lot more than this this patch, and it did
reveal a problem with how I've implemented the initial XOR when the
buffer is split, so I have some minor updates coming soon.
Christoph Hellwig Feb. 25, 2022, 4:19 p.m. UTC | #4 
On Fri, Feb 25, 2022 at 08:12:59AM -0800, Keith Busch wrote:
> I don't have experience with kunit, but I'll look into that.
> 
> I am already changing the way this gets tested. Eric recommended adding
> to the crypto "testmgr", and I've done that on my private tree. That
> test framework exercises a lot more than this this patch, and it did
> reveal a problem with how I've implemented the initial XOR when the
> buffer is split, so I have some minor updates coming soon.

I guess if we exercise the algorithm through that we don't really need
another low-level test anyway, right?
diff mbox series

Patch

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 14b89aa37c5c..149de11ae903 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2214,6 +2214,10 @@  config TEST_UUID
 config TEST_XARRAY
 	tristate "Test the XArray code at runtime"
 
+config TEST_CRC64
+	depends on CRC64
+	tristate "Test the crc64 code at runtime"
+
 config TEST_OVERFLOW
 	tristate "Test check_*_overflow() functions at runtime"
 
diff --git a/lib/Makefile b/lib/Makefile
index 130bed83cdf2..0895a3fc3f5a 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -103,6 +103,7 @@  obj-$(CONFIG_TEST_HMM) += test_hmm.o
 obj-$(CONFIG_TEST_FREE_PAGES) += test_free_pages.o
 obj-$(CONFIG_KPROBES_SANITY_TEST) += test_kprobes.o
 obj-$(CONFIG_TEST_REF_TRACKER) += test_ref_tracker.o
+obj-$(CONFIG_TEST_CRC64) += test_crc64.o
 #
 # CFLAGS for compiling floating point code inside the kernel. x86/Makefile turns
 # off the generation of FPU/SSE* instructions for kernel proper but FPU_FLAGS
diff --git a/lib/test_crc64.c b/lib/test_crc64.c
new file mode 100644
index 000000000000..281aacd20f0a
--- /dev/null
+++ b/lib/test_crc64.c
@@ -0,0 +1,133 @@ 
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Tests were selected from NVM Express NVM Command Set Specification 1.0a,
+ * section 5.2.1.3.5 "64b CRC Test Cases" available here:
+ *
+ *   https://nvmexpress.org/wp-content/uploads/NVMe-NVM-Command-Set-Specification-1.0a-2021.07.26-Ratified.pdf
+ *
+ * Copyright 2022 Keith Busch <kbusch@kernel.org>
+ */
+
+#include <linux/crc64.h>
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include <linux/random.h>
+
+static unsigned int tests_passed;
+static unsigned int tests_run;
+
+#define ALL_ZEROS 0x6482D367EB22B64EULL
+#define ALL_FFS 0xC0DDBA7302ECA3ACULL
+#define INC 0x3E729F5F6750449CULL
+#define DEC 0x9A2DF64B8E9E517EULL
+
+static u8 buffer[4096];
+
+#define CRC_CHECK(c, v) do {					\
+	tests_run++;						\
+	if (c != v)						\
+		printk("BUG at %s:%d expected:%llx got:%llx\n", \
+			__func__, __LINE__, v, c);		\
+	else							\
+		tests_passed++;					\
+} while (0)
+
+static void randomize(u64 *b, int size)
+{
+	int i;
+
+	for (i = 0; i < size / 8; i++)
+		b[i] = get_random_u64();
+}
+
+static void crc_speed_tests(void)
+{
+	unsigned long size = 1 << 20;
+	unsigned test_size;
+	void *b;
+
+	b = vmalloc(size);
+	if (!b)
+		return;
+
+	test_size = 512;
+	while (test_size <= size) {
+		ktime_t start_time, end_time;
+		u64 crc1, crc2;
+		s64 t1, t2;
+		int i;
+
+		randomize(b, test_size);
+		crc1 = crc2 = ~0ULL;
+
+		start_time = ktime_get();
+		for (i = 0; i < 1024; i++)
+			crc1 = crc64_rocksoft_generic(crc1, b, test_size);
+		end_time = ktime_get();
+		t1 = ktime_us_delta(end_time, start_time);
+
+		start_time = ktime_get();
+		for (i = 0; i < 1024; i++)
+			crc2 = crc64_rocksoft_update(crc2, b, test_size);
+		end_time = ktime_get();
+		t2 = ktime_us_delta(end_time, start_time);
+
+		printk("Size:%-7u Generic:%-7lld Library:%lld\n", test_size,
+			t1, t2);
+		CRC_CHECK(crc1, crc2);
+
+		test_size <<= 1;
+	}
+
+        vfree(b);
+}
+
+static int crc_tests(void)
+{
+	__u64 crc;
+	int i;
+
+	memset(buffer, 0, sizeof(buffer));
+	crc = crc64_rocksoft_generic(~0ULL, buffer, 4096);
+	CRC_CHECK(crc, ALL_ZEROS);
+
+	crc = crc64_rocksoft(buffer, 4096);
+	CRC_CHECK(crc, ALL_ZEROS);
+
+	memset(buffer, 0xff, sizeof(buffer));
+	crc = crc64_rocksoft_generic(~0ULL, buffer, 4096);
+	CRC_CHECK(crc, ALL_FFS);
+
+	crc = crc64_rocksoft(buffer, 4096);
+	CRC_CHECK(crc, ALL_FFS);
+
+	for (i = 0; i < 4096; i++)
+		buffer[i] = i & 0xff;
+	crc = crc64_rocksoft_generic(~0ULL, buffer, 4096);
+	CRC_CHECK(crc, INC);
+
+	crc = crc64_rocksoft(buffer, 4096);
+	CRC_CHECK(crc, INC);
+
+	for (i = 0; i < 4096; i++)
+		buffer[i] = 0xff - (i & 0xff);
+	crc = crc64_rocksoft_generic(~0ULL, buffer, 4096);
+	CRC_CHECK(crc, DEC);
+
+	crc = crc64_rocksoft(buffer, 4096);
+	CRC_CHECK(crc, DEC);
+
+	crc_speed_tests();
+
+	printk("CRC64: %u of %u tests passed\n", tests_passed, tests_run);
+	return (tests_run == tests_passed) ? 0 : -EINVAL;
+}
+
+static void crc_exit(void)
+{
+}
+
+module_init(crc_tests);
+module_exit(crc_exit);
+MODULE_AUTHOR("Keith Busch <kbusch@kernel.org>");
+MODULE_LICENSE("GPL");