syscall_get_nr — find what system call a task is executing
int syscall_get_nr ( | struct task_struct * task, |
struct pt_regs * regs); |
If task is executing a system call or is at system call
tracing about to attempt one, returns the system call number.
If task is not executing a system call, i.e. it's blocked
inside the kernel for a fault or signal, returns -1.
Note this returns int even on 64-bit machines. Only 32 bits of system call number can be meaningful. If the actual arch value is 64 bits, this truncates to 32 bits so 0xffffffff means -1.
It's only valid to call this when task is known to be blocked.