openssl使用cryptodev引擎的速度測試與硬件加速器一起導致虛假的計時結果

Question

我想獲得我的硬件的加密性能測試，同時這樣做我使用openssl速度測試命令。

第一測試I執行是不啓用硬件加速：

$ openssl speed -evp aes-128-cbc -engine cryptodev 
Doing aes-128-cbc for 3s on 16 size blocks: 4437806 aes-128-cbc's in 3.00s 
Doing aes-128-cbc for 3s on 64 size blocks: 1244528 aes-128-cbc's in 3.00s 
Doing aes-128-cbc for 3s on 256 size blocks: 322780 aes-128-cbc's in 3.00s 
Doing aes-128-cbc for 3s on 1024 size blocks: 81429 aes-128-cbc's in 3.00s 
Doing aes-128-cbc for 3s on 8192 size blocks: 10215 aes-128-cbc's in 3.00s 

OpenSSL 1.0.1j 15 Oct 2014 
built on: Thu Jul 23 18:58:46 CDT 2015 
options:bn(64,32) rc4(ptr,char) des(idx,cisc,16,long) aes(partial) idea(int) blowfish(ptr) 
compiler: arm-poky-linux-gnueabi-gcc -march=armv7-a -mthumb-interwork -mfloat-abi=hard 
-mfpu=neon -mtune=cortex-a9 --sysroot=... -fPIC -DOPENSSL_PIC -DOPENSSL_THREADS 
-D_REENTRANT -DDSO_DLFCN -DHAVE_DLFCN_H -DL_ENDIAN -DTERMIO -O2 -pipe -g 
-feliminate-unused-debug-types -Wall -Wa,--noexecstack -DHAVE_CRYPTODEV -DUSE_CRYPTODEV_DIGESTS 
-DOPENSSL_BN_ASM_MONT -DOPENSSL_BN_ASM_GF2m -DSHA1_ASM -DSHA256_ASM -DSHA512_ASM 
-DAES_ASM -DGHASH_ASM 

The 'numbers' are in 1000s of bytes per second processed. 
type    16 bytes  64 bytes 256 bytes 1024 bytes 8192 bytes 
aes-128-cbc  23668.30k 26549.93k 27543.89k 27794.43k 27893.76k 

然後啓用硬件加速，並得到下面的結果：

$ openssl speed -evp aes-128-cbc -engine cryptodev 
engine "cryptodev" set. 
Doing aes-128-cbc for 3s on 16 size blocks: 39552 aes-128-cbc's in ***0.08s*** 
Doing aes-128-cbc for 3s on 64 size blocks: 37060 aes-128-cbc's in ***0.05s*** 
Doing aes-128-cbc for 3s on 256 size blocks: 32674 aes-128-cbc's in ***0.07s*** 
Doing aes-128-cbc for 3s on 1024 size blocks: 26101 aes-128-cbc's in ***0.06s*** 
Doing aes-128-cbc for 3s on 8192 size blocks: 8286 aes-128-cbc's in ***0.02s*** 

OpenSSL 1.0.1j 15 Oct 2014 
built on: Thu Jul 23 18:58:46 CDT 2015 
options:bn(64,32) rc4(ptr,char) des(idx,cisc,16,long) aes(partial) idea(int) blowfish(ptr) 
compiler: arm-poky-linux-gnueabi-gcc -march=armv7-a -mthumb-interwork -mfloat-abi=hard 
-mfpu=neon -mtune=cortex-a9 --sysroot=.... -fPIC -DOPENSSL_PIC -DOPENSSL_THREADS 
-D_REENTRANT -DDSO_DLFCN -DHAVE_DLFCN_H -DL_ENDIAN -DTERMIO -O2 -pipe -g 
-feliminate-unused-debug-types -Wall -Wa,--noexecstack -DHAVE_CRYPTODEV -DUSE_CRYPTODEV_DIGESTS 
-DOPENSSL_BN_ASM_MONT -DOPENSSL_BN_ASM_GF2m -DSHA1_ASM -DSHA256_ASM -DSHA512_ASM 
-DAES_ASM -DGHASH_ASM 

The 'numbers' are in 1000s of bytes per second processed. 
type    16 bytes  64 bytes 256 bytes 1024 bytes 8192 bytes 

我的問題是，爲什麼在測試運行了10秒毫秒，當測試應該爲每個塊大小運行3秒。這是OpenSSL中的錯誤嗎？

---

我通過OpenSSL的版本1.0.1j代碼去了，以下是我發現：

#ifndef OPENSSL_NO_AES 
     if (doit[D_CBC_128_AES]) 
       { 
       for (j=0; j<SIZE_NUM; j++) 
         { 
         print_message(names[D_CBC_128_AES],c[D_CBC_128_AES][j],lengths[j]); 
         Time_F(START); 
         for (count=0,run=1; COND(c[D_CBC_128_AES][j]); count++) 
           AES_cbc_encrypt(buf,buf, 
             (unsigned long)lengths[j],&aes_ks1, 
             iv,AES_ENCRYPT); 
         d=Time_F(STOP); 
         print_result(D_CBC_128_AES,j,count,d); 
         } 
       } 

這裏Time_F定義如下：

static double Time_F(int s) 
     { 
     return app_tminterval(s,usertime); 
     } 
#endif 

app_tminterval定義如：

#else 
#include <sys/time.h> 
#include <sys/resource.h> 

double app_tminterval(int stop,int usertime) 
     { 
     double   ret = 0; 
     struct rusage rus; 
     struct timeval now; 
     static struct timeval tmstart; 

     if (usertime)   getrusage(RUSAGE_SELF,&rus), now = rus.ru_utime; 
     else     gettimeofday(&now,NULL); 

     if (stop==TM_START)  tmstart = now; 
     else     ret = ((now.tv_sec+now.tv_usec*1e-6) 
             - (tmstart.tv_sec+tmstart.tv_usec*1e-6)); 

     return ret; 
     } 
#endif 

在這裏，我很困惑如何處理應用程序間隔小於10ms的時間，而沒有硬件加速器的實際測試運行3秒。

謝謝

Answer 1

使用-elapsed來衡量總時間。

Openssl測量CPU時間，當您將算法卸載到硬件加速器時，可以釋放CPU使用量。因此，openssl不會將大部分時間都計算在CPU之外。