Merge branch 'hash' of git://ftp.sciencehorizons.net/linux

Pull string hash improvements from George Spelvin: "This series does several related things: - Makes the dcache hash (fs/namei.c) useful for general kernel use. (Thanks to Bruce for noticing the zero-length corner case) - Converts the string hashes in <linux/sunrpc/svcauth.h> to use the above. - Avoids 64-bit multiplies in hash_64() on 32-bit platforms. Two 32-bit multiplies will do well enough. - Rids the world of the bad hash multipliers in hash_32. This finishes the job started in commit 689de1d6ca95 ("Minimal fix-up of bad hashing behavior of hash_64()") The vast majority of Linux architectures have hardware support for 32x32-bit multiply and so derive no benefit from "simplified" multipliers. The few processors that do not (68000, h8/300 and some models of Microblaze) have arch-specific implementations added. Those patches are last in the series. - Overhauls the dcache hash mixing. The patch in commit 0fed3ac866ea ("namei: Improve hash mixing if CONFIG_DCACHE_WORD_ACCESS") was an off-the-cuff suggestion. Replaced with a much more careful design that's simultaneously faster and better. (My own invention, as there was noting suitable in the literature I could find. Comments welcome!) - Modify the hash_name() loop to skip the initial HASH_MIX(). This would let us salt the hash if we ever wanted to. - Sort out partial_name_hash(). The hash function is declared as using a long state, even though it's truncated to 32 bits at the end and the extra internal state contributes nothing to the result. And some callers do odd things: - fs/hfs/string.c only allocates 32 bits of state - fs/hfsplus/unicode.c uses it to hash 16-bit unicode symbols not bytes - Modify bytemask_from_count to handle inputs of 1..sizeof(long) rather than 0..sizeof(long)-1. This would simplify users other than full_name_hash" Special thanks to Bruce Fields for testing and finding bugs in v1. (I learned some humbling lessons about "obviously correct" code.) On the arch-specific front, the m68k assembly has been tested in a standalone test harness, I've been in contact with the Microblaze maintainers who mostly don't care, as the hardware multiplier is never omitted in real-world applications, and I haven't heard anything from the H8/300 world" * 'hash' of git://ftp.sciencehorizons.net/linux: h8300: Add <asm/hash.h> microblaze: Add <asm/hash.h> m68k: Add <asm/hash.h> <linux/hash.h>: Add support for architecture-specific functions fs/namei.c: Improve dcache hash function Eliminate bad hash multipliers from hash_32() and hash_64() Change hash_64() return value to 32 bits <linux/sunrpc/svcauth.h>: Define hash_str() in terms of hashlen_string() fs/namei.c: Add hashlen_string() function Pull out string hash to <linux/stringhash.h>
author: Linus Torvalds <torvalds@linux-foundation.org> 2016-05-28 19:15:25 -0400
committer: Linus Torvalds <torvalds@linux-foundation.org> 2016-05-28 19:15:25 -0400
commit: 7e0fb73c52c4037b4d5ef9ff56c7296a3151bd92 (patch)
tree: 9ab023505d388563d937b3c3ac26ef3c2045dba2 /lib
parent: 4e8440b3b6b801953b2e53c55491cf98fc8f6c01 (diff)
parent: 4684fe95300c071983f77653e354c040fe80a265 (diff)
3 files changed, 262 insertions, 0 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index e707ab3e1991..77d7d034bac3 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1849,6 +1849,17 @@ config TEST_RHASHTABLE
          If unsure, say N.
+config TEST_HASH
+        tristate "Perform selftest on hash functions"
+        default n
+        help
+          Enable this option to test the kernel's integer (<linux/hash,h>)
+          and string (<linux/stringhash.h>) hash functions on boot
+          (or module load).
+          This is intended to help people writing architecture-specific
+          optimized versions.  If unsure, say N.
 endmenu # runtime tests
 config PROVIDE_OHCI1394_DMA_INIT
diff --git a/lib/Makefile b/lib/Makefile
index 42b69185f963..499fb354d627 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -48,6 +48,7 @@ obj-$(CONFIG_TEST_HEXDUMP) += test_hexdump.o
 obj-y += kstrtox.o
 obj-$(CONFIG_TEST_BPF) += test_bpf.o
 obj-$(CONFIG_TEST_FIRMWARE) += test_firmware.o
+obj-$(CONFIG_TEST_HASH) += test_hash.o
 obj-$(CONFIG_TEST_KASAN) += test_kasan.o
 obj-$(CONFIG_TEST_KSTRTOX) += test-kstrtox.o
 obj-$(CONFIG_TEST_LKM) += test_module.o
diff --git a/lib/test_hash.c b/lib/test_hash.c
new file mode 100644
index 000000000000..c9549c8b4909
--- /dev/null
+++ b/lib/test_hash.c
@@ -0,0 +1,250 @@
+/*
+ * Test cases for <linux/hash.h> and <linux/stringhash.h>
+ * This just verifies that various ways of computing a hash
+ * produce the same thing and, for cases where a k-bit hash
+ * value is requested, is of the requested size.
+ *
+ * We fill a buffer with a 255-byte null-terminated string,
+ * and use both full_name_hash() and hashlen_string() to hash the
+ * substrings from i to j, where 0 <= i < j < 256.
+ *
+ * The returned values are used to check that __hash_32() and
+ * __hash_32_generic() compute the same thing.  Likewise hash_32()
+ * and hash_64().
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt "\n"
+#include <linux/compiler.h>
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/hash.h>
+#include <linux/stringhash.h>
+#include <linux/printk.h>
+/* 32-bit XORSHIFT generator.  Seed must not be zero. */
+static u32 __init __attribute_const__
+xorshift(u32 seed)
+{
+        seed ^= seed << 13;
+        seed ^= seed >> 17;
+        seed ^= seed << 5;
+        return seed;
+}
+/* Given a non-zero x, returns a non-zero byte. */
+static u8 __init __attribute_const__
+mod255(u32 x)
+{
+        x = (x & 0xffff) + (x >> 16);   /* 1 <= x <= 0x1fffe */
+        x = (x & 0xff) + (x >> 8);      /* 1 <= x <= 0x2fd */
+        x = (x & 0xff) + (x >> 8);      /* 1 <= x <= 0x100 */
+        x = (x & 0xff) + (x >> 8);      /* 1 <= x <= 0xff */
+        return x;
+}
+/* Fill the buffer with non-zero bytes. */
+static void __init
+fill_buf(char *buf, size_t len, u32 seed)
+{
+        size_t i;
+        for (i = 0; i < len; i++) {
+                seed = xorshift(seed);
+                buf[i] = mod255(seed);
+        }
+}
+/*
+ * Test the various integer hash functions.  h64 (or its low-order bits)
+ * is the integer to hash.  hash_or accumulates the OR of the hash values,
+ * which are later checked to see that they cover all the requested bits.
+ *
+ * Because these functions (as opposed to the string hashes) are all
+ * inline, the code being tested is actually in the module, and you can
+ * recompile and re-test the module without rebooting.
+ */
+static bool __init
+test_int_hash(unsigned long long h64, u32 hash_or[2][33])
+{
+        int k;
+        u32 h0 = (u32)h64, h1, h2;
+        /* Test __hash32 */
+        hash_or[0][0] |= h1 = __hash_32(h0);
+#ifdef HAVE_ARCH__HASH_32
+        hash_or[1][0] |= h2 = __hash_32_generic(h0);
+#if HAVE_ARCH__HASH_32 == 1
+        if (h1 != h2) {
+                pr_err("__hash_32(%#x) = %#x != __hash_32_generic() = %#x",
+                        h0, h1, h2);
+                return false;
+        }
+#endif
+#endif
+        /* Test k = 1..32 bits */
+        for (k = 1; k <= 32; k++) {
+                u32 const m = ((u32)2 << (k-1)) - 1;    /* Low k bits set */
+                /* Test hash_32 */
+                hash_or[0][k] |= h1 = hash_32(h0, k);
+                if (h1 > m) {
+                        pr_err("hash_32(%#x, %d) = %#x > %#x", h0, k, h1, m);
+                        return false;
+                }
+#ifdef HAVE_ARCH_HASH_32
+                h2 = hash_32_generic(h0, k);
+#if HAVE_ARCH_HASH_32 == 1
+                if (h1 != h2) {
+                        pr_err("hash_32(%#x, %d) = %#x != hash_32_generic() "
+                                " = %#x", h0, k, h1, h2);
+                        return false;
+                }
+#else
+                if (h2 > m) {
+                        pr_err("hash_32_generic(%#x, %d) = %#x > %#x",
+                                h0, k, h1, m);
+                        return false;
+                }
+#endif
+#endif
+                /* Test hash_64 */
+                hash_or[1][k] |= h1 = hash_64(h64, k);
+                if (h1 > m) {
+                        pr_err("hash_64(%#llx, %d) = %#x > %#x", h64, k, h1, m);
+                        return false;
+                }
+#ifdef HAVE_ARCH_HASH_64
+                h2 = hash_64_generic(h64, k);
+#if HAVE_ARCH_HASH_64 == 1
+                if (h1 != h2) {
+                        pr_err("hash_64(%#llx, %d) = %#x != hash_64_generic() "
+                                "= %#x", h64, k, h1, h2);
+                        return false;
+                }
+#else
+                if (h2 > m) {
+                        pr_err("hash_64_generic(%#llx, %d) = %#x > %#x",
+                                h64, k, h1, m);
+                        return false;
+                }
+#endif
+#endif
+        }
+        (void)h2;       /* Suppress unused variable warning */
+        return true;
+}
+#define SIZE 256        /* Run time is cubic in SIZE */
+static int __init
+test_hash_init(void)
+{
+        char buf[SIZE+1];
+        u32 string_or = 0, hash_or[2][33] = { 0 };
+        unsigned tests = 0;
+        unsigned long long h64 = 0;
+        int i, j;
+        fill_buf(buf, SIZE, 1);
+        /* Test every possible non-empty substring in the buffer. */
+        for (j = SIZE; j > 0; --j) {
+                buf[j] = '\0';
+                for (i = 0; i <= j; i++) {
+                        u64 hashlen = hashlen_string(buf+i);
+                        u32 h0 = full_name_hash(buf+i, j-i);
+                        /* Check that hashlen_string gets the length right */
+                        if (hashlen_len(hashlen) != j-i) {
+                                pr_err("hashlen_string(%d..%d) returned length"
+                                        " %u, expected %d",
+                                        i, j, hashlen_len(hashlen), j-i);
+                                return -EINVAL;
+                        }
+                        /* Check that the hashes match */
+                        if (hashlen_hash(hashlen) != h0) {
+                                pr_err("hashlen_string(%d..%d) = %08x != "
+                                        "full_name_hash() = %08x",
+                                        i, j, hashlen_hash(hashlen), h0);
+                                return -EINVAL;
+                        }
+                        string_or |= h0;
+                        h64 = h64 << 32 | h0;   /* For use with hash_64 */
+                        if (!test_int_hash(h64, hash_or))
+                                return -EINVAL;
+                        tests++;
+                } /* i */
+        } /* j */
+        /* The OR of all the hash values should cover all the bits */
+        if (~string_or) {
+                pr_err("OR of all string hash results = %#x != %#x",
+                        string_or, -1u);
+                return -EINVAL;
+        }
+        if (~hash_or[0][0]) {
+                pr_err("OR of all __hash_32 results = %#x != %#x",
+                        hash_or[0][0], -1u);
+                return -EINVAL;
+        }
+#ifdef HAVE_ARCH__HASH_32
+#if HAVE_ARCH__HASH_32 != 1     /* Test is pointless if results match */
+        if (~hash_or[1][0]) {
+                pr_err("OR of all __hash_32_generic results = %#x != %#x",
+                        hash_or[1][0], -1u);
+                return -EINVAL;
+        }
+#endif
+#endif
+        /* Likewise for all the i-bit hash values */
+        for (i = 1; i <= 32; i++) {
+                u32 const m = ((u32)2 << (i-1)) - 1;    /* Low i bits set */
+                if (hash_or[0][i] != m) {
+                        pr_err("OR of all hash_32(%d) results = %#x "
+                                "(%#x expected)", i, hash_or[0][i], m);
+                        return -EINVAL;
+                }
+                if (hash_or[1][i] != m) {
+                        pr_err("OR of all hash_64(%d) results = %#x "
+                                "(%#x expected)", i, hash_or[1][i], m);
+                        return -EINVAL;
+                }
+        }
+        /* Issue notices about skipped tests. */
+#ifndef HAVE_ARCH__HASH_32
+        pr_info("__hash_32() has no arch implementation to test.");
+#elif HAVE_ARCH__HASH_32 != 1
+        pr_info("__hash_32() is arch-specific; not compared to generic.");
+#endif
+#ifndef HAVE_ARCH_HASH_32
+        pr_info("hash_32() has no arch implementation to test.");
+#elif HAVE_ARCH_HASH_32 != 1
+        pr_info("hash_32() is arch-specific; not compared to generic.");
+#endif
+#ifndef HAVE_ARCH_HASH_64
+        pr_info("hash_64() has no arch implementation to test.");
+#elif HAVE_ARCH_HASH_64 != 1
+        pr_info("hash_64() is arch-specific; not compared to generic.");
+#endif
+        pr_notice("%u tests passed.", tests);
+        return 0;
+}
+static void __exit test_hash_exit(void)
+{
+}
+module_init(test_hash_init);    /* Does everything */
+module_exit(test_hash_exit);    /* Does nothing */
+MODULE_LICENSE("GPL");
author	Linus Torvalds <torvalds@linux-foundation.org>	2016-05-28 19:15:25 -0400
committer	Linus Torvalds <torvalds@linux-foundation.org>	2016-05-28 19:15:25 -0400
commit	7e0fb73c52c4037b4d5ef9ff56c7296a3151bd92 (patch)
tree	9ab023505d388563d937b3c3ac26ef3c2045dba2 /lib
parent	4e8440b3b6b801953b2e53c55491cf98fc8f6c01 (diff)
parent	4684fe95300c071983f77653e354c040fe80a265 (diff)

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index e707ab3e1991..77d7d034bac3 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug
@@ -1849,6 +1849,17 @@ config TEST_RHASHTABLE
1849		1849
1850	If unsure, say N.	1850	If unsure, say N.
1851		1851
		1852	config TEST_HASH
		1853	tristate "Perform selftest on hash functions"
		1854	default n
		1855	help
		1856	Enable this option to test the kernel's integer (<linux/hash,h>)
		1857	and string (<linux/stringhash.h>) hash functions on boot
		1858	(or module load).
		1859
		1860	This is intended to help people writing architecture-specific
		1861	optimized versions. If unsure, say N.
		1862
1852	endmenu # runtime tests	1863	endmenu # runtime tests
1853		1864
1854	config PROVIDE_OHCI1394_DMA_INIT	1865	config PROVIDE_OHCI1394_DMA_INIT


diff --git a/lib/Makefile b/lib/Makefile index 42b69185f963..499fb354d627 100644 --- a/lib/Makefile +++ b/lib/Makefile
@@ -48,6 +48,7 @@ obj-$(CONFIG_TEST_HEXDUMP) += test_hexdump.o
48	obj-y += kstrtox.o	48	obj-y += kstrtox.o
49	obj-$(CONFIG_TEST_BPF) += test_bpf.o	49	obj-$(CONFIG_TEST_BPF) += test_bpf.o
50	obj-$(CONFIG_TEST_FIRMWARE) += test_firmware.o	50	obj-$(CONFIG_TEST_FIRMWARE) += test_firmware.o
		51	obj-$(CONFIG_TEST_HASH) += test_hash.o
51	obj-$(CONFIG_TEST_KASAN) += test_kasan.o	52	obj-$(CONFIG_TEST_KASAN) += test_kasan.o
52	obj-$(CONFIG_TEST_KSTRTOX) += test-kstrtox.o	53	obj-$(CONFIG_TEST_KSTRTOX) += test-kstrtox.o
53	obj-$(CONFIG_TEST_LKM) += test_module.o	54	obj-$(CONFIG_TEST_LKM) += test_module.o


diff --git a/lib/test_hash.c b/lib/test_hash.c new file mode 100644 index 000000000000..c9549c8b4909 --- /dev/null +++ b/lib/test_hash.c
@@ -0,0 +1,250 @@
		1	/*
		2	* Test cases for <linux/hash.h> and <linux/stringhash.h>
		3	* This just verifies that various ways of computing a hash
		4	* produce the same thing and, for cases where a k-bit hash
		5	* value is requested, is of the requested size.
		6	*
		7	* We fill a buffer with a 255-byte null-terminated string,
		8	* and use both full_name_hash() and hashlen_string() to hash the
		9	* substrings from i to j, where 0 <= i < j < 256.
		10	*
		11	* The returned values are used to check that __hash_32() and
		12	* __hash_32_generic() compute the same thing. Likewise hash_32()
		13	* and hash_64().
		14	*/
		15
		16	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt "\n"
		17
		18	#include <linux/compiler.h>
		19	#include <linux/types.h>
		20	#include <linux/module.h>
		21	#include <linux/hash.h>
		22	#include <linux/stringhash.h>
		23	#include <linux/printk.h>
		24
		25	/* 32-bit XORSHIFT generator. Seed must not be zero. */
		26	static u32 __init __attribute_const__
		27	xorshift(u32 seed)
		28	{
		29	seed ^= seed << 13;
		30	seed ^= seed >> 17;
		31	seed ^= seed << 5;
		32	return seed;
		33	}
		34
		35	/* Given a non-zero x, returns a non-zero byte. */
		36	static u8 __init __attribute_const__
		37	mod255(u32 x)
		38	{
		39	x = (x & 0xffff) + (x >> 16); /* 1 <= x <= 0x1fffe */
		40	x = (x & 0xff) + (x >> 8); /* 1 <= x <= 0x2fd */
		41	x = (x & 0xff) + (x >> 8); /* 1 <= x <= 0x100 */
		42	x = (x & 0xff) + (x >> 8); /* 1 <= x <= 0xff */
		43	return x;
		44	}
		45
		46	/* Fill the buffer with non-zero bytes. */
		47	static void __init
		48	fill_buf(char *buf, size_t len, u32 seed)
		49	{
		50	size_t i;
		51
		52	for (i = 0; i < len; i++) {
		53	seed = xorshift(seed);
		54	buf[i] = mod255(seed);
		55	}
		56	}
		57
		58	/*
		59	* Test the various integer hash functions. h64 (or its low-order bits)
		60	* is the integer to hash. hash_or accumulates the OR of the hash values,
		61	* which are later checked to see that they cover all the requested bits.
		62	*
		63	* Because these functions (as opposed to the string hashes) are all
		64	* inline, the code being tested is actually in the module, and you can
		65	* recompile and re-test the module without rebooting.
		66	*/
		67	static bool __init
		68	test_int_hash(unsigned long long h64, u32 hash_or[2][33])
		69	{
		70	int k;
		71	u32 h0 = (u32)h64, h1, h2;
		72
		73	/* Test __hash32 */
		74	hash_or[0][0] \|= h1 = __hash_32(h0);
		75	#ifdef HAVE_ARCH__HASH_32
		76	hash_or[1][0] \|= h2 = __hash_32_generic(h0);
		77	#if HAVE_ARCH__HASH_32 == 1
		78	if (h1 != h2) {
		79	pr_err("__hash_32(%#x) = %#x != __hash_32_generic() = %#x",
		80	h0, h1, h2);
		81	return false;
		82	}
		83	#endif
		84	#endif
		85
		86	/* Test k = 1..32 bits */
		87	for (k = 1; k <= 32; k++) {
		88	u32 const m = ((u32)2 << (k-1)) - 1; /* Low k bits set */
		89
		90	/* Test hash_32 */
		91	hash_or[0][k] \|= h1 = hash_32(h0, k);
		92	if (h1 > m) {
		93	pr_err("hash_32(%#x, %d) = %#x > %#x", h0, k, h1, m);
		94	return false;
		95	}
		96	#ifdef HAVE_ARCH_HASH_32
		97	h2 = hash_32_generic(h0, k);
		98	#if HAVE_ARCH_HASH_32 == 1
		99	if (h1 != h2) {
		100	pr_err("hash_32(%#x, %d) = %#x != hash_32_generic() "
		101	" = %#x", h0, k, h1, h2);
		102	return false;
		103	}
		104	#else
		105	if (h2 > m) {
		106	pr_err("hash_32_generic(%#x, %d) = %#x > %#x",
		107	h0, k, h1, m);
		108	return false;
		109	}
		110	#endif
		111	#endif
		112	/* Test hash_64 */
		113	hash_or[1][k] \|= h1 = hash_64(h64, k);
		114	if (h1 > m) {
		115	pr_err("hash_64(%#llx, %d) = %#x > %#x", h64, k, h1, m);
		116	return false;
		117	}
		118	#ifdef HAVE_ARCH_HASH_64
		119	h2 = hash_64_generic(h64, k);
		120	#if HAVE_ARCH_HASH_64 == 1
		121	if (h1 != h2) {
		122	pr_err("hash_64(%#llx, %d) = %#x != hash_64_generic() "
		123	"= %#x", h64, k, h1, h2);
		124	return false;
		125	}
		126	#else
		127	if (h2 > m) {
		128	pr_err("hash_64_generic(%#llx, %d) = %#x > %#x",
		129	h64, k, h1, m);
		130	return false;
		131	}
		132	#endif
		133	#endif
		134	}
		135
		136	(void)h2; /* Suppress unused variable warning */
		137	return true;
		138	}
		139
		140	#define SIZE 256 /* Run time is cubic in SIZE */
		141
		142	static int __init
		143	test_hash_init(void)
		144	{
		145	char buf[SIZE+1];
		146	u32 string_or = 0, hash_or[2][33] = { 0 };
		147	unsigned tests = 0;
		148	unsigned long long h64 = 0;
		149	int i, j;
		150
		151	fill_buf(buf, SIZE, 1);
		152
		153	/* Test every possible non-empty substring in the buffer. */
		154	for (j = SIZE; j > 0; --j) {
		155	buf[j] = '\0';
		156
		157	for (i = 0; i <= j; i++) {
		158	u64 hashlen = hashlen_string(buf+i);
		159	u32 h0 = full_name_hash(buf+i, j-i);
		160
		161	/* Check that hashlen_string gets the length right */
		162	if (hashlen_len(hashlen) != j-i) {
		163	pr_err("hashlen_string(%d..%d) returned length"
		164	" %u, expected %d",
		165	i, j, hashlen_len(hashlen), j-i);
		166	return -EINVAL;
		167	}
		168	/* Check that the hashes match */
		169	if (hashlen_hash(hashlen) != h0) {
		170	pr_err("hashlen_string(%d..%d) = %08x != "
		171	"full_name_hash() = %08x",
		172	i, j, hashlen_hash(hashlen), h0);
		173	return -EINVAL;
		174	}
		175
		176	string_or \|= h0;
		177	h64 = h64 << 32 \| h0; /* For use with hash_64 */
		178	if (!test_int_hash(h64, hash_or))
		179	return -EINVAL;
		180	tests++;
		181	} /* i */
		182	} /* j */
		183
		184	/* The OR of all the hash values should cover all the bits */
		185	if (~string_or) {
		186	pr_err("OR of all string hash results = %#x != %#x",
		187	string_or, -1u);
		188	return -EINVAL;
		189	}
		190	if (~hash_or[0][0]) {
		191	pr_err("OR of all __hash_32 results = %#x != %#x",
		192	hash_or[0][0], -1u);
		193	return -EINVAL;
		194	}
		195	#ifdef HAVE_ARCH__HASH_32
		196	#if HAVE_ARCH__HASH_32 != 1 /* Test is pointless if results match */
		197	if (~hash_or[1][0]) {
		198	pr_err("OR of all __hash_32_generic results = %#x != %#x",
		199	hash_or[1][0], -1u);
		200	return -EINVAL;
		201	}
		202	#endif
		203	#endif
		204
		205	/* Likewise for all the i-bit hash values */
		206	for (i = 1; i <= 32; i++) {
		207	u32 const m = ((u32)2 << (i-1)) - 1; /* Low i bits set */
		208
		209	if (hash_or[0][i] != m) {
		210	pr_err("OR of all hash_32(%d) results = %#x "
		211	"(%#x expected)", i, hash_or[0][i], m);
		212	return -EINVAL;
		213	}
		214	if (hash_or[1][i] != m) {
		215	pr_err("OR of all hash_64(%d) results = %#x "
		216	"(%#x expected)", i, hash_or[1][i], m);
		217	return -EINVAL;
		218	}
		219	}
		220
		221	/* Issue notices about skipped tests. */
		222	#ifndef HAVE_ARCH__HASH_32
		223	pr_info("__hash_32() has no arch implementation to test.");
		224	#elif HAVE_ARCH__HASH_32 != 1
		225	pr_info("__hash_32() is arch-specific; not compared to generic.");
		226	#endif
		227	#ifndef HAVE_ARCH_HASH_32
		228	pr_info("hash_32() has no arch implementation to test.");
		229	#elif HAVE_ARCH_HASH_32 != 1
		230	pr_info("hash_32() is arch-specific; not compared to generic.");
		231	#endif
		232	#ifndef HAVE_ARCH_HASH_64
		233	pr_info("hash_64() has no arch implementation to test.");
		234	#elif HAVE_ARCH_HASH_64 != 1
		235	pr_info("hash_64() is arch-specific; not compared to generic.");
		236	#endif
		237
		238	pr_notice("%u tests passed.", tests);
		239
		240	return 0;
		241	}
		242
		243	static void __exit test_hash_exit(void)
		244	{
		245	}
		246
		247	module_init(test_hash_init); /* Does everything */
		248	module_exit(test_hash_exit); /* Does nothing */
		249
		250	MODULE_LICENSE("GPL");