Even when a mount namespace is created, previously host's sysfs is used,
especially with RootDirectory= or RootImage=, thus service processes can
still access the properties of the network interfaces in the main network
namespace through sysfs.
This makes, sysfs is remounted with the new network namespace tag, except
when PrivateMounts= is explicitly disabled. Hence, the properties of the
network interfaces in the main network namespace cannot be accessed by
service processes through sysfs.
Fixes#26422.
This is useful when creating a new network namespace. Unlike procfs,
we need to remount sysfs, otherwise properties of the network interfaces
in the main network namespace are still accessible through the old sysfs,
e.g. /sys/class/net/eth0. All sub-mounts previously mounted on the sysfs
are moved onto the new sysfs mount.
The function will be used in later commits.
If the boot ID cannot be obtained, let's first fallback to the machine
ID, and if still cannot, then let's use 0.
Otherwise, no timer event source cannot be triggered.
Fixes#26549.
In older glibc (like 2.28 on CentOS Stream 8) there is no wrapper
for the gettid() syscall, so we need to provide our own.
../src/libsystemd/sd-journal/journal-send.c: In function ‘close_journal_fd’:
../src/libsystemd/sd-journal/journal-send.c:88:25: error: implicit declaration of function ‘gettid’; did you mean ‘getgid’? [-Werror=implicit-function-declaration]
if (getpid() != gettid())
^~~~~~
getgid
../src/libsystemd/sd-journal/journal-send.c:88:25: warning: nested extern declaration of ‘gettid’ [-Wnested-externs]
cc1: some warnings being treated as errors
Follow-up to 50b35193ec.
Now that device path types are marked as packed we can safely cast and
access them. If we ever take the address of a member, we would get a
compiler warning.
In gnu-efi/EDK2 device paths are not marked as packed and instead the
Length field is split into 2 bytes. Accessing those requires these
helper macros as device paths may be unaligned.
Since our own efi headers define device path structs as packed, we can
access these directly, making code much more readable.
usec_t is also a uint64_t internally, hence this doesn't actually change
anything. However, on the conceptual level, sd-bus expects a uint64_t
hence give it one.
Timespans are probably best right-aligned, in particular if they
systematically end in either " ago" or " left" because they are used as
"relative timestamps".
Only service and scope units have RuntimeMaxUSec bus property.
To suppress the "Until:" field for other unit types, the entry must be
initialized with USEC_INFINITY.
Fixes#26473.
Typically, in reasonably complex programs we want to realease various
caches (such as glibc allocation caches) in case of memory pressure.
Let's add explicit infrastructure for that to sd-event, that can hook
Linux' Pressure Stall Information (PSI) logic with our event loop.
This adds sd_event_add_memory_pressure() as easy, one-step API to
install an even source that is called under memory pressure.
The parameters which file to watch (the per-cgroup PSI file, or the
system-wide file /proc/pressure/memory) can be configured via env vars.
The idea is that the service manager sooner or later gains controls for
setting this up correctly.
Alternatively to the PSI a similar logic is supported but instead of
waiting for POLLPRI on a procfs/cgroupfs fd we'll wait for POLLIN on
FIFO or AF_UNIX sockets. This is useful for testing, and possibly in
other environments, for example to hook up this protocol directly with
GNOME's low memory monitor.
By default this watches on the cgroup-local PSI so that we aren't
affected by pressure on cgroups we are not related to.
Mike Yuan
Lennart Poettering
Yu Watanabe
Frantisek Sumsal
Jan Janssen
Daan De Meyer