385                 CALL(sys_syncfs)
386                 CALL(sys_sendmmsg)
387 /* 375 */       CALL(sys_setns)
388                 CALL(sys_process_vm_readv)
389                 CALL(sys_process_vm_writev)
390 /* 378 */       CALL(sys_my_add)
391 #ifndef syscalls_counted
392 .equ syscalls_padding, ((NR_syscalls + 3) & ~3) - NR_syscalls
393 #define syscalls_counted
394 #endif
395 .rept syscalls_padding
396                 CALL(sys_ni_syscall)
397 .endr

403 #define __NR_sendmmsg                   (__NR_SYSCALL_BASE+374)
404 #define __NR_setns                      (__NR_SYSCALL_BASE+375)
405 #define __NR_process_vm_readv           (__NR_SYSCALL_BASE+376)
406 #define __NR_process_vm_writev          (__NR_SYSCALL_BASE+377)
407 #define __NR_my_add                     (__NR_SYSCALL_BASE+378)
408
409 /*
410  * The following SWIs are ARM private.
411  */
412 #define __ARM_NR_BASE                   (__NR_SYSCALL_BASE+0x0f0000)
413 #define __ARM_NR_breakpoint             (__ARM_NR_BASE+1)
414 #define __ARM_NR_cacheflush             (__ARM_NR_BASE+2)
415 #define __ARM_NR_usr26                  (__ARM_NR_BASE+3)

  1 #include <linux/init.h>2 #include <linux/sched.h>3 #include <linux/module.h>4 #include "mysyscall.h"5 /* asmlinkage long sys_arm_fadvise64_64(int fd, int advice,6                                       loff_t offset, loff_t len)7  {8          return sys_fadvise64_64(fd, offset, len, advice);9  }                                                          */10 //asmlinkage:表示将来这段代码是要由汇编来调用的。11  asmlinkage long sys_my_add(int a,int b)12  {13         printk("this is liuye's syscall!\n");14          return a+b;15  }16 17 //module_init(sys_my_add);18 MODULE_LICENSE("GPL");

  1 #ifndef __MYSYSCALL_H_2 #define __MYSYSCALL_H_3 4  asmlinkage long sys_my_add(int a,int b);5 6 7 #endif

  1 obj-y += mysyscall.o

 74 AFLAGS_iwmmxt.o                 := -Wa,-mcpu=iwmmxt75 obj-$(CONFIG_ARM_CPU_TOPOLOGY)  += topology.o76 # 在这层malefile中添加下一曾Makefile路径77 obj-y  += mysyscall/78 

  1 //这三行是为了调用syscall而包含的头文件和宏定义:可以man syscall查看2 #define _GNU_SOURCE         /* See feature_test_macros(7) */3 #include <unistd.h>4 #include <sys/syscall.h>   /* For SYS_xxx definitions */5 #include <stdio.h>6 int my_add(int a ,int b)7 {8         printf("this is liuye's app\n");9         return  syscall(378,a,b);10 11 }

  1 #ifndef __MY_ADD_H_2 #define __MY_ADD_H_3 4 extern int my_add(int a, int b);5 6 #endif

[liuye@LiuYe 01syscall]$>arm-linux-gcc -fPIC -c -o my_add.o my_add.c
[liuye@LiuYe 01syscall]$>arm-linux-gcc my_add.o -shared -o libadd.so

  1 #include <stdio.h>2 #include "my_add.h"3 //#include <my_add.h>4 int main(void)5 {6         int sum;7         sum = my_add(1,2);8         printf("sum = %d\n",sum);9         return 0;10 }

77     使用arm-linux-gcc编译test.c代码，需要链接动态库 -L指定路径  -l指定库名
78     生成可执行文件：arm-linux-gcc test.c -o test -L./ -ladd
79     复制库文件和可执行文件到共享文件夹:cp libadd.so test /myroot
81     把新编译的内核copy到SD卡，刷机;
82     PC端：1 开启共享服务
83           2 minicom链接开发板
84             mount -t nfs -o nolock,rw 192.168.1.10:/myroot /mnt
85             cd /mnt
86             cp libadd.so /lib/ 放到根下lib下，在运行的时候不用指定路径
87             ./test  运行即

root@board liuye_dir#./test
this is liuye's app
[ 1817.020000] this is liuye's syscall!
sum = 3
root@board liuye_dir#