[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 (file)
--- 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 @@ static unsigned int IDX[8] = { IDX1, IDX2, IDX3, IDX4, IDX5, IDX6, IDX7, IDX8 };
 /*
  * Used by test_cipher_speed()
  */
-static unsigned int sec = 10;
+static unsigned int sec;
 
 static int mode;
 static char *xbuf;
@@ -426,6 +428,88 @@ out:
        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 @@ static void test_cipher_speed(char *algo, int mode, int enc, unsigned int sec,
        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 @@ static void test_cipher_speed(char *algo, int mode, int enc, unsigned int sec,
                        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_exit(fini);
 
 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");