gettimeofday() -- user-space vs. system call

gettimeofday() -- user-space vs. system call

Posted Feb 7, 2007 16:53 UTC (Wed) by nix (subscriber, #2304)
In reply to: gettimeofday() -- user-space vs. system call by AnswerGuy
Parent article: Comparing Linux and Minix

You don't need any libc support for this (other than the existing vsyscall support). The code on the vsyscall page which normally runs SYSENTER could spot that the syscall being invoked is gettimeofday() and copy out the appropriate value from elsewhere in the vsyscall page without ever transitioning to kernel mode. (A patch of this nature was discussed a few years ago, but I'm not sure if any code resulted.)

---

(Log in to post comments)