ipc/namespace.c: use a work queue to free_ipc
the reason is to avoid a delay caused by the synchronize_rcu() call in
kern_umount() when the mqueue mount is freed.
the code:
#define _GNU_SOURCE
#include <sched.h>
#include <error.h>
#include <errno.h>
#include <stdlib.h>
int main()
{
int i;
for (i = 0; i < 1000; i++)
if (unshare(CLONE_NEWIPC) < 0)
error(EXIT_FAILURE, errno, "unshare");
}
goes from
Command being timed: "./ipc-namespace"
User time (seconds): 0.00
System time (seconds): 0.06
Percent of CPU this job got: 0%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:08.05
to
Command being timed: "./ipc-namespace"
User time (seconds): 0.00
System time (seconds): 0.02
Percent of CPU this job got: 96%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:00.03
Signed-off-by: Giuseppe Scrivano <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Reviewed-by: Paul E. McKenney <[email protected]>
Reviewed-by: Waiman Long <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: Manfred Spraul <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>
2 files changed