Initial scaffolding

1 files changed, 95 insertions, 0 deletions

diff --git a/main.c b/main.c
new file mode 100644
index 0000000..cab65b3
--- /dev/null
+++ b/main.c
@@ -0,0 +1,95 @@
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * Copyright (C) 2018-2022 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/sort.h>
+#include <linux/random.h>
+#include <asm/cpufeature.h>
+#include <asm/processor.h>
+#include <asm/fpu/api.h>
+#include <asm/simd.h>
+
+static unsigned long stamp = 0;
+module_param(stamp, ulong, 0);
+
+#define declare_it(name) bool mix_ ##name(u32 h[4], const u32 v[4])
+
+#define local_it(name) cycles_t median_ ##name = 0
+
+#define do_it(name) do { \
+	u32 eax = 0, ebx = 0, ecx = 0, edx = 0; \
+	for (i = 0; i < WARMUP; ++i) \
+		ret |= mix_ ##name(pool, input); \
+	asm volatile("cpuid" : "+a" (eax), "=b" (ebx), "=d" (edx), "+c" (ecx)); \
+	for (i = 0; i <= TRIALS; ++i) { \
+		trial_times[i] = get_cycles(); \
+		ret |= mix_ ##name(pool, input); \
+	} \
+	for (i = 0; i < TRIALS; ++i) \
+		trial_times[i] = trial_times[i + 1] - trial_times[i]; \
+	sort(trial_times, TRIALS + 1, sizeof(cycles_t), compare_cycles, NULL); \
+	median_ ## name = trial_times[TRIALS / 2]; \
+} while (0)
+
+#define report_it(name) do { \
+	pr_err("%lu: %12s: %6llu cycles per call\n", stamp, #name, median_ ## name); \
+} while (0)
+
+#define forall(f) \
+	f(spelvin); \
+	f(rotxor32); \
+	f(rotxor64); \
+	f(speck); \
+	f(quarcha); \
+	f(sparkle); \
+	f(siphash); \
+	f(hsiphash); \
+	f(lfsr); \
+	f(lfsr2);
+
+forall(declare_it)
+
+static int compare_cycles(const void *a, const void *b)
+{
+	return *((cycles_t *)a) - *((cycles_t *)b);
+}
+
+static int __init mod_init(void)
+{
+	enum { WARMUP = 6000, TRIALS = 100000, IDLE = 1 * 1000 };
+	int ret = 0, i;
+	cycles_t *trial_times;
+	forall(local_it)
+	unsigned long flags;
+	DEFINE_SPINLOCK(lock);
+	u32 pool[4] = { 0 }, input[4];
+
+	get_random_bytes(input, sizeof(input));
+
+	trial_times = kcalloc(TRIALS + 1, sizeof(cycles_t), GFP_KERNEL);
+	if (!trial_times)
+		return -ENOMEM;
+
+	msleep(IDLE);
+	spin_lock_irqsave(&lock, flags);
+	forall(do_it)
+	spin_unlock_irqrestore(&lock, flags);
+	forall(report_it)
+	kfree(trial_times);
+	
+	/* We should never actually agree to insert the module. Choosing
+	 * -0x1000 here is an amazing hack. It causes the kernel to not
+	 * actually load the module, while the standard userspace tools
+	 * don't return an error, because it's too big. */
+	return -0x1000;
+}
+
+module_init(mod_init);
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("kBench9000 Cycle Counter");
+MODULE_AUTHOR("Jason A. Donenfeld <Jason@zx2c4.com>");