Commit c71458d20f17ef747cb314f2526701454e35335a
1 parent
4d907d60f9
Exists in
master
Context switch working
Showing 1 changed file with 28 additions and 40 deletions Side-by-side Diff
osproject_cswitch.c
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c71458d
| ... | ... | @@ -19,62 +19,50 @@ |
| 19 | 19 | * express or implied warranty. |
| 20 | 20 | */ |
| 21 | 21 | |
| 22 | -#ifndef lint | |
| 23 | -static char rcsid[] = "$Header: /sprite/src/benchmarks/cswitch/RCS/cswitch.c,v 1.1 89/08/31 13:19:37 ouster Exp $ SPRITE (Berkeley)"; | |
| 24 | -#endif not lint | |
| 25 | - | |
| 26 | 22 | #include <stdio.h> |
| 27 | -#include <sys/time.h> | |
| 28 | - | |
| 29 | -main(argc,argv) | |
| 30 | - int argc; | |
| 31 | - char **argv; | |
| 23 | +int main(int argc, char **argv) | |
| 32 | 24 | { |
| 33 | 25 | int count, i, toSlave[2], fromSlave[2]; |
| 34 | 26 | int pid; |
| 35 | 27 | char buffer[10]; |
| 36 | - struct timeval begin ,end; | |
| 37 | - int micros; | |
| 28 | + unsigned int begin ,end; | |
| 38 | 29 | double timePer; |
| 39 | - extern int errno; | |
| 30 | + unsigned int regr; | |
| 31 | + asm volatile("mrc p15, 0, %0, c9, c14, 0" : "=r" (regr)); | |
| 32 | + printf("regr: %x\n", regr); | |
| 40 | 33 | |
| 41 | - if (argc != 2 ) { | |
| 42 | - fprintf(stderr, "Ping takes one argument: count.\n"); | |
| 43 | - return; | |
| 44 | - } | |
| 45 | - count = 0; | |
| 46 | - sscanf(argv[1], "%d", &count); | |
| 34 | + count = 10; | |
| 47 | 35 | pipe(toSlave); |
| 48 | 36 | pipe(fromSlave); |
| 49 | 37 | pid = fork(); |
| 50 | - if (pid == 0) { | |
| 51 | - write(fromSlave[1], "a", 1); | |
| 52 | - while (1) { | |
| 53 | - read(toSlave[0], buffer, 1); | |
| 54 | - if (buffer[0] != 'a') { | |
| 55 | - exit(0); | |
| 56 | - } | |
| 57 | - write(fromSlave[1], "a", 1); | |
| 58 | - } | |
| 38 | + if (pid == 0) { | |
| 39 | + write(fromSlave[1], "a", 1); | |
| 40 | + while (1) { | |
| 41 | + read(toSlave[0], buffer, 1); | |
| 42 | + asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (end)); | |
| 43 | + if (buffer[0] != 'a') { | |
| 44 | + printf("Exiting\n"); | |
| 45 | + return -1; | |
| 46 | + } | |
| 47 | + //write(fromSlave[1], "a", 1); | |
| 48 | + printf("end: %u\n", end); | |
| 49 | + } | |
| 59 | 50 | } |
| 60 | - if (pid == -1) { | |
| 61 | - fprintf(stderr, "Couldn't fork slave process: error %d.\n", | |
| 62 | - errno); | |
| 63 | - return; | |
| 64 | - } | |
| 51 | + if (pid == -1) { | |
| 52 | + printf("Couldn't fork slave process: error %d.\n"); | |
| 53 | + return; | |
| 54 | + } | |
| 65 | 55 | read(fromSlave[0], buffer, 1); |
| 66 | - gettimeofday(&begin, (struct timezone *) NULL); | |
| 67 | 56 | for (i = 0; i < count; i++) { |
| 68 | - write(toSlave[1], "a", 1); | |
| 69 | - read(fromSlave[0], buffer, 1); | |
| 57 | + asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (begin)); | |
| 58 | + write(toSlave[1], "a", 1); | |
| 59 | + //read(fromSlave[0], buffer, 1); | |
| 60 | + usleep(10000); | |
| 61 | + printf("Start: %u\n", begin); | |
| 70 | 62 | } |
| 71 | - gettimeofday(&end, (struct timezone *) NULL); | |
| 72 | - micros = 1000000*(end.tv_sec - begin.tv_sec) | |
| 73 | - + end.tv_usec - begin.tv_usec; | |
| 74 | 63 | write(toSlave[1], "b", 1); |
| 75 | - timePer = micros; | |
| 76 | - timePer /= count * 1000; | |
| 77 | 64 | |
| 65 | + timePer = (end - begin)/count; | |
| 78 | 66 | printf("Elapsed time per ping (2 context switches): %.2f milliseconds.\n", |
| 79 | 67 | timePer); |
| 80 | 68 | } |