linux/include
Giuseppe Scrivano e1eb26fa62 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 <gscrivan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Waiman Long <longman@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Manfred Spraul <manfred@colorfullife.com>
Link: http://lkml.kernel.org/r/20200225145419.527994-1-gscrivan@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-08 11:05:56 -07:00
..
acpi
asm-generic powerpc updates for 5.8 2020-06-05 12:39:30 -07:00
clocksource
crypto
drm drm: remove drm specific kmap_atomic code 2020-06-04 19:06:22 -07:00
dt-bindings Char/Misc driver patches for 5.8-rc1 2020-06-07 10:59:32 -07:00
keys
kunit
kvm
linux ipc/namespace.c: use a work queue to free_ipc 2020-06-08 11:05:56 -07:00
math-emu
media media updates for v5.8-rc1 2020-06-03 20:59:38 -07:00
misc
net
pcmcia
ras
rdma RDMA 5.8 merge window pull request 2020-06-05 14:05:57 -07:00
scsi SCSI misc on 20200605 2020-06-05 15:11:50 -07:00
soc pci-v5.8-changes 2020-06-06 11:01:58 -07:00
sound
target
trace AFS Changes 2020-06-05 16:26:36 -07:00
uapi Char/Misc driver patches for 5.8-rc1 2020-06-07 10:59:32 -07:00
vdso
video
xen