tree-wide: remove Emacs lines from all files This should be handled fine now by .dir-locals.el, so need to carry that stuff in every file.

test-cgroup-mask: check return value CID #1339830.

tree-wide: sort includes Sort the includes accoding to the new coding style.

core: enable TasksMax= for all services by default, and set it to 512 Also, enable TasksAccounting= for all services by default, too. See: http://lists.freedesktop.org/archives/systemd-devel/2015-November/035006.html

core: unified cgroup hierarchy support This patch set adds full support the new unified cgroup hierarchy logic of modern kernels. A new kernel command line option "systemd.unified_cgroup_hierarchy=1" is added. If specified the unified hierarchy is mounted to /sys/fs/cgroup instead of a tmpfs. No further hierarchies are mounted. The kernel command line option defaults to off. We can turn it on by default as soon as the kernel's APIs regarding this are stabilized (but even then downstream distros might want to turn this off, as this will break any tools that access cgroupfs directly). It is possibly to choose for each boot individually whether the unified or the legacy hierarchy is used. nspawn will by default provide the legacy hierarchy to containers if the host is using it, and the unified otherwise. However it is possible to run containers with the unified hierarchy on a legacy host and vice versa, by setting the $UNIFIED_CGROUP_HIERARCHY environment variable for nspawn to 1 or 0, respectively. The unified hierarchy provides reliable cgroup empty notifications for the first time, via inotify. To make use of this we maintain one manager-wide inotify fd, and each cgroup to it. This patch also removes cg_delete() which is unused now. On kernel 4.2 only the "memory" controller is compatible with the unified hierarchy, hence that's the only controller systemd exposes when booted in unified heirarchy mode. This introduces a new enum for enumerating supported controllers, plus a related enum for the mask bits mapping to it. The core is changed to make use of this everywhere. This moves PID 1 into a new "init.scope" implicit scope unit in the root slice. This is necessary since on the unified hierarchy cgroups may either contain subgroups or processes but not both. PID 1 hence has to move out of the root cgroup (strictly speaking the root cgroup is the only one where processes and subgroups are still allowed, but in order to support containers nicey, we move PID 1 into the new scope in all cases.) This new unit is also used on legacy hierarchy setups. It's actually pretty useful on all systems, as it can then be used to filter journal messages coming from PID 1, and so on. The root slice ("-.slice") is now implicitly created and started (and does not require a unit file on disk anymore), since that's where "init.scope" is located and the slice needs to be started before the scope can. To check whether we are in unified or legacy hierarchy mode we use statfs() on /sys/fs/cgroup. If the .f_type field reports tmpfs we are in legacy mode, if it reports cgroupfs we are in unified mode. This patch set carefuly makes sure that cgls and cgtop continue to work as desired. When invoking nspawn as a service it will implicitly create two subcgroups in the cgroup it is using, one to move the nspawn process into, the other to move the actual container processes into. This is done because of the requirement that cgroups may either contain processes or other subgroups.

test-cgroup-mask: unit_get_sibling_mask ignores cgroup_supported The result of unit_get_sibling_mask returns bits for the sibling cgroups even if they are not supported in the local system. I caught this on a machine where my kernel was misconfigured with CONFIG_MEMCG unset, but the rest of the cgroup infrastructure enabled. Tested with `make check` on a host running a kernel where CONFIG_MEMCG is not set.

core: rename SystemdRunningAs to ManagerRunningAs It's primarily just a property of the Manager object after all, and we try to refer to PID 1 as "manager" instead of "systemd", hence let's to stick to this here too.

remove unused includes This patch removes includes that are not used. The removals were found with include-what-you-use which checks if any of the symbols from a header is in use.

test: only use assert_se The asserts used in the tests should never be allowed to be optimized away

test-cgroup-mask: fix masks in test and enable by default Commit 637f421e5c6a ("cgroups: always propagate controller membership to siblings") changed the mask propagation logic, but the test wasn't updated. Move to normal tests from manual tests, it should not touch the system anymore.

test-cgroup-mask: pass on kernels without memory controller It seems that unit_get_siblings_mask returns the controllers filtered by what is available, but get_members_mask and get_cgroup_mask do not. This just fixes the test following the symptoms.

test-engine: fix access to unit load path Also add a bit of debugging output to help diagnose problems, add missing units, and simplify cppflags. Move test-engine to normal tests from manual tests, it should now work without destroying the system.

make gcc shut up If -flto is used then gcc will generate a lot more warnings than before, among them a number of use-without-initialization warnings. Most of them without are false positives, but let's make them go away, because it doesn't really matter.

core: rework cgroup mask propagation Previously a cgroup setting down tree would result in cgroup membership additions being propagated up the tree and to the siblings, however a unit could never lose cgroup memberships again. With this change we'll make sure that both cgroup additions and removals propagate properly.

fix scan-build issues The static analyzer scan-build had a few issues with analysing parts of systemd. gpt-auto-generator.c: scan-build could not find blkid.h. Whether it should be blkid.h or blkid/blkid.h seems to depend on the version used. We already use blkid/blkid.h in udev-builtin-blkid.c so it seems safe to use that here too. Makefile.am: Moved some -D's from CFLAGS to CPPFLAGS. I also simplified them a bit and got rid of a left over DBUS_CFLAGS. test-cgroup-mask.c/test-sched-prio.c A variable was added to store the replaced TEST_DIR. When wrapped in an assert_se TEST_DIR was not replaced in the logged error. While not an issue introduced in this patch we might as well fix it up while we are here.

core: allocate a kdbus bus for each systemd instance, if we can

cgroups: Cache controller masks and optimize queues.