This changes cg_enable_everywhere() to return which controllers are
enabled for the specified cgroup. This information is then used to
correctly track the enablement mask currently in effect for a unit.
Moreover, when we try to turn off a controller, and this works, then
this is indicates that the parent unit might succesfully turn it off
now, too as our unit might have kept it busy.
So far, when realizing cgroups, i.e. when syncing up the kernel
representation of relevant cgroups with our own idea we would strictly
work from the root to the leaves. This is generally a good approach, as
when controllers are enabled this has to happen in root-to-leaves order.
However, when controllers are disabled this has to happen in the
opposite order: in leaves-to-root order (this is because controllers can
only be enabled in a child if it is already enabled in the parent, and
if it shall be disabled in the parent then it has to be disabled in the
child first, otherwise it is considered busy when it is attempted to
remove it in the parent).
To make things complicated when invalidating a unit's cgroup membershup
systemd can actually turn off some controllers previously turned on at
the very same time as it turns on other controllers previously turned
off. In such a case we have to work up leaves-to-root *and*
root-to-leaves right after each other. With this patch this is
implemented: we still generally operate root-to-leaves, but as soon as
we noticed we successfully turned off a controller previously turned on
for a cgroup we'll re-enqueue the cgroup realization for all parents of
a unit, thus implementing leaves-to-root where necessary.
Ideally, coccinelle would strip unnecessary braces too. But I do not see any
option in coccinelle for this, so instead, I edited the patch text using
search&replace to remove the braces. Unfortunately this is not fully automatic,
in particular it didn't deal well with if-else-if-else blocks and ifdefs, so
there is an increased likelikehood be some bugs in such spots.
I also removed part of the patch that coccinelle generated for udev, where we
returns -1 for failure. This should be fixed independently.
Commit 100d5f6ee6 (user-util: add new wrappers for [...] database
files), ammended by commit 4f07ffa8f5 (Use #if instead of #ifdef for
ENABLE_GSHADOW) moved code from sysuser to basic/user-util.
In doing so, the combination of both commits properly propagated the
ENABLE_GSHADOW conditions around the function manipulating gshadow, but
they forgot to protect the inclusion of the gshadow.h header.
Fix that to be able to build on C libraries that do not provide gshadow
(e.g. uClibc-ng, where it does not exist.)
This changes DEFINE_MAIN_FUNCTION_WITH_POSITIVE_FAILURE() to propagate positive
return values as they were, i.e. stops mapping them all to EXIT_FAILURE. This
was suggested in review, but I thought that we only ever return EXIT_FAILURE,
so we don't need to propagate multiple return values.
I was wrong. Turns out that we already *do* have multiple positive return
values, when we call external binaries and propagate the result. systemd-inhibit
is one example, and b453c447e0 actually broke
this propagation. This commit fixes it.
In systemd-fsck we have the opposite case: we have only one failure value, and the
code needs to be adjusted, so that it keeps returning EXIT_FAILURE.
All other users of DEFINE_MAIN_FUNCTION_WITH_POSITIVE_FAILURE() return <= 1, and
are unaffected by this change.
We generally want to close the pager last. This patch closes the pager last,
after the static destuctor calls. This means that they can do logging and such
like during normal program runtime.
This doesn't have much effect on the final build, because we link libbasic.a
into libsystemd-shared.so, so in the end, all the object built from basic/
end up in libsystemd-shared. And when the static library is linked into binaries,
any objects that are included in it but are not used are trimmed. Hence, the
size of output artifacts doesn't change:
$ du -sb /var/tmp/inst*
54181861 /var/tmp/inst1 (old)
54207441 /var/tmp/inst1s (old split-usr)
54182477 /var/tmp/inst2 (new)
54208041 /var/tmp/inst2s (new split-usr)
(The negligible change in size is because libsystemd-shared.so is bigger
by a few hundred bytes. I guess it's because symbols are named differently
or something like that.)
The effect is on the build process, in particular partial builds. This change
effectively moves the requirements on some build steps toward the leaves of the
dependency tree. Two effects:
- when building items that do not depend on libsystemd-shared, we
build less stuff for libbasic.a (which wouldn't be used anyway,
so it's a net win).
- when building items that do depend on libshared, we reduce libbasic.a as a
synchronization point, possibly allowing better parallelism.
Method:
1. copy list of .h files from src/basic/meson.build to /tmp/basic
2. $ for i in $(grep '.h$' /tmp/basic); do echo $i; git --no-pager grep "include \"$i\"" src/basic/ 'src/lib*' 'src/nss-*' 'src/journal/sd-journal.c' |grep -v "${i%.h}.c";echo ;done | less
Code was not doing a wait() after kill() due to checking for a return value > 0, and was leaving zombie processes. This affected things like sd-bus unixexec connections.
As suggest here:
https://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html#Attribute-Syntax
"You may optionally specify attribute names with ‘__’ preceding and
following the name. This allows you to use them in header files without
being concerned about a possible macro of the same name. For example,
you may use the attribute name __noreturn__ instead of noreturn. "
This way, we can extend the macro a bit with stuff pulled in from other
headers without this affecting everything which pulls in macro.h, which
is one of our most basic headers.
This is just refactoring, no change in behaviour, in prepartion for
later changes.
It was only used in one place, where we don't actually need it, and
it is too easy to forget to update it when adding new items to the table.
Let's just drop it.
systemd only uses functions that are as of Linux 4.15+ provided
externally to the CPU controller (currently usage_usec), so if we have a
new enough kernel, we don't need to set CGROUP_MASK_CPU for
CPUAccounting=true as the CPU controller does not need to necessarily be
enabled in this case.
Part of this patch is modelled on an earlier patch by Ryutaroh Matsumoto
(see PR #9665).
I decided to use a separate definition for this because it's too easy to return
positive from functions which don't need this distinction and only return
negative on error and success otherwise.
If we create a cgroup in one controller it might already have been
created in another too, if we have jointly mounted controllers. Take
that into consideration.
The function takes a pointer to a random block of memory and
the length of that block. It shouldn't crash every time it sees
a zero byte at the beginning there.
This should help the dev-kmsg fuzzer to keep going.
With gcc-7.1.1-3.fc26.aarch64:
../src/basic/json.c: In function ‘json_format’:
../src/basic/json.c:1409:40: warning: comparison is always true due to limited range of data type [-Wtype-limits]
if (*q >= 0 && *q < ' ')
^~
../src/basic/json.c: In function ‘inc_lines_columns’:
../src/basic/json.c:1762:31: warning: comparison is always true due to limited range of data type [-Wtype-limits]
} else if (*s >= 0 && *s < 127) /* Process ASCII chars quickly */
^~
Cast to (signed char) silences the warning, but a cast to (int) for some reason
doesn't.
