[CRYPTO]: Use CPU cycle counters in tcrypt
After using this facility for a while to test my changes to the
cipher crypt() layer, I realised that I should've listend to Dave
and made this thing use CPU cycle counters :) As it is it's too
jittery for me to feel safe about relying on the results.
So here is a patch to make it use CPU cycles by default but fall
back to jiffies if the user specifies a non-zero sec value.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/crypto/tcrypt.c b/crypto/tcrypt.c
index 401d25a..bd7524c 100644
--- a/crypto/tcrypt.c
+++ b/crypto/tcrypt.c
@@ -27,6 +27,8 @@
#include <linux/highmem.h>
#include <linux/moduleparam.h>
#include <linux/jiffies.h>
+#include <linux/timex.h>
+#include <linux/interrupt.h>
#include "tcrypt.h"
/*
@@ -60,7 +62,7 @@
/*
* Used by test_cipher_speed()
*/
-static unsigned int sec = 10;
+static unsigned int sec;
static int mode;
static char *xbuf;
@@ -426,6 +428,88 @@
crypto_free_tfm(tfm);
}
+static int test_cipher_jiffies(struct crypto_tfm *tfm, int enc, char *p,
+ int blen, int sec)
+{
+ struct scatterlist sg[8];
+ unsigned long start, end;
+ int bcount;
+ int ret;
+
+ sg[0].page = virt_to_page(p);
+ sg[0].offset = offset_in_page(p);
+ sg[0].length = blen;
+
+ for (start = jiffies, end = start + sec * HZ, bcount = 0;
+ time_before(jiffies, end); bcount++) {
+ if (enc)
+ ret = crypto_cipher_encrypt(tfm, sg, sg, blen);
+ else
+ ret = crypto_cipher_decrypt(tfm, sg, sg, blen);
+
+ if (ret)
+ return ret;
+ }
+
+ printk("%d operations in %d seconds (%ld bytes)\n",
+ bcount, sec, (long)bcount * blen);
+ return 0;
+}
+
+static int test_cipher_cycles(struct crypto_tfm *tfm, int enc, char *p,
+ int blen)
+{
+ struct scatterlist sg[8];
+ unsigned long cycles = 0;
+ int ret = 0;
+ int i;
+
+ sg[0].page = virt_to_page(p);
+ sg[0].offset = offset_in_page(p);
+ sg[0].length = blen;
+
+ local_bh_disable();
+ local_irq_disable();
+
+ /* Warm-up run. */
+ for (i = 0; i < 4; i++) {
+ if (enc)
+ ret = crypto_cipher_encrypt(tfm, sg, sg, blen);
+ else
+ ret = crypto_cipher_decrypt(tfm, sg, sg, blen);
+
+ if (ret)
+ goto out;
+ }
+
+ /* The real thing. */
+ for (i = 0; i < 8; i++) {
+ cycles_t start, end;
+
+ start = get_cycles();
+ if (enc)
+ ret = crypto_cipher_encrypt(tfm, sg, sg, blen);
+ else
+ ret = crypto_cipher_decrypt(tfm, sg, sg, blen);
+ end = get_cycles();
+
+ if (ret)
+ goto out;
+
+ cycles += end - start;
+ }
+
+out:
+ local_irq_enable();
+ local_bh_enable();
+
+ if (ret == 0)
+ printk("1 operation in %lu cycles (%d bytes)\n",
+ (cycles + 4) / 8, blen);
+
+ return ret;
+}
+
static void test_cipher_speed(char *algo, int mode, int enc, unsigned int sec,
struct cipher_testvec *template,
unsigned int tcount, struct cipher_speed *speed)
@@ -433,8 +517,6 @@
unsigned int ret, i, j, iv_len;
unsigned char *key, *p, iv[128];
struct crypto_tfm *tfm;
- struct scatterlist sg[8];
- unsigned long start, bcount;
const char *e, *m;
if (enc == ENCRYPT)
@@ -492,25 +574,16 @@
crypto_cipher_set_iv(tfm, iv, iv_len);
}
- for (start = jiffies, bcount = 0;
- ((jiffies - start) / HZ) < sec; bcount++) {
- sg[0].page = virt_to_page(p);
- sg[0].offset = offset_in_page(p);
- sg[0].length = speed[i].blen;
+ if (sec)
+ ret = test_cipher_jiffies(tfm, enc, p, speed[i].blen,
+ sec);
+ else
+ ret = test_cipher_cycles(tfm, enc, p, speed[i].blen);
- if (enc)
- ret = crypto_cipher_encrypt(tfm, sg, sg, speed[i].blen);
- else
- ret = crypto_cipher_decrypt(tfm, sg, sg, speed[i].blen);
-
- if (ret) {
- printk("%s () failed flags=%x\n", e, tfm->crt_flags);
- goto out;
- }
+ if (ret) {
+ printk("%s() failed flags=%x\n", e, tfm->crt_flags);
+ break;
}
-
- printk("%lu operations in %u seconds (%lu bytes)\n",
- bcount, sec, bcount * speed[i].blen);
}
out:
@@ -1063,7 +1136,8 @@
module_param(mode, int, 0);
module_param(sec, uint, 0);
-MODULE_PARM_DESC(sec, "Length in seconds of speed tests");
+MODULE_PARM_DESC(sec, "Length in seconds of speed tests "
+ "(defaults to zero which uses CPU cycles instead)");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Quick & dirty crypto testing module");