kernel: use kernel_wait4() instead of sys_wait4()

All call sites of sys_wait4() set *rusage to NULL. Therefore, there is
no need for the copy_to_user() handling of *rusage, and we can use
kernel_wait4() directly.

This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net

Acked-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
This commit is contained in:
Dominik Brodowski
2018-03-11 11:34:26 +01:00
parent 819671ff84
commit d300b61081
3 changed files with 6 additions and 6 deletions

View File

@@ -242,16 +242,16 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns)
/*
* Reap the EXIT_ZOMBIE children we had before we ignored SIGCHLD.
* sys_wait4() will also block until our children traced from the
* kernel_wait4() will also block until our children traced from the
* parent namespace are detached and become EXIT_DEAD.
*/
do {
clear_thread_flag(TIF_SIGPENDING);
rc = sys_wait4(-1, NULL, __WALL, NULL);
rc = kernel_wait4(-1, NULL, __WALL, NULL);
} while (rc != -ECHILD);
/*
* sys_wait4() above can't reap the EXIT_DEAD children but we do not
* kernel_wait4() above can't reap the EXIT_DEAD children but we do not
* really care, we could reparent them to the global init. We could
* exit and reap ->child_reaper even if it is not the last thread in
* this pid_ns, free_pid(pid_allocated == 0) calls proc_cleanup_work(),