mallinfo is not specified by POSIX or the C standards, therefore
it's not available for all libc libraries (musl).
Add the ability to disable mallinfo statistics.
Fixes:
selinux-util.c: In function ‘mac_selinux_init’:
selinux-util.c:70:25: error: storage size of ‘before_mallinfo’ isn’t known
struct mallinfo before_mallinfo, after_mallinfo;
Signed-off-by: Romain Naour <romain.naour@openwide.fr>
* configure.ac: use LT_LIBM to check for the maths library
* src/accelerometer/Makefile.am: use $(LIBM) instead of -lm in the link
flags
This causes all executables (except accelerometer) and libraries to be
linked without libm, which they do not need.
We reintroduce hashmap.{h,c}, list.h and set.h verbatim from upstream,
before we punt dead code. The following is the upstream message:
This is a rewrite of the hashmap implementation. Its advantage is lower
memory usage.
It uses open addressing (entries are stored in an array, as opposed to
linked lists). Hash collisions are resolved with linear probing and
Robin Hood displacement policy. See the references in hashmap.c.
Some fun empirical findings about hashmap usage in systemd on my laptop:
- 98 % of allocated hashmaps are Sets.
- Sets contain 78 % of all entries, plain Hashmaps 17 %, and
OrderedHashmaps 5 %.
- 60 % of allocated hashmaps contain only 1 entry.
- 90 % of allocated hashmaps contain 5 or fewer entries.
- 75 % of all entries are in hashmaps that use trivial_hash_ops.
Clearly it makes sense to:
- store entries in distinct entry types. Especially for Sets - their
entries are the most numerous and they require the least information
to store an entry.
- have a way to store small numbers of entries directly in the hashmap
structs, and only allocate the usual entry arrays when the direct
storage is full.
The implementation has an optional debugging feature (enabled by
defining the ENABLE_HASHMAP_DEBUG macro), where it:
- tracks all allocated hashmaps in a linked list so that one can
easily find them in gdb,
- tracks which function/line allocated a given hashmap, and
- checks for invalid mixing of hashmap iteration and modification.
Since entries are not allocated one-by-one anymore, mempools are not
used for entries. Originally I meant to drop mempools entirely, but it's
still worth it to use them for the hashmap structs. My testing indicates
that it makes loading of units about 5 % faster (a test with 10000 units
where more than 200000 hashmaps are allocated - pure malloc: 449±4 ms,
mempools: 427±7 ms).
Here are some memory usage numbers, taken on my laptop with a more or
less normal Fedora setup after booting with SELinux disabled (SELinux
increases systemd's memory usage significantly):
systemd (PID 1) Original New Change
dirty memory (from pmap -x 1) [KiB] 2152 1264 -41 %
total heap allocations (from gdb-heap) [KiB] 1623 756 -53 %
Signed-off-by: Anthony G. Basile <blueness@gentoo.org>
This is a combination of upstream commits
dced15575f7bf172e3c9d798c43477539525558c
7bed7f0e3b1f9596aedb64657e432e5b267adebb
by
Simon McVittie <simon.mcvittie@collabora.co.uk>
7bed7f0e3b1f9596aedb64657e432e5b267adebb
Signed-off-by: Anthony G. Basile <blueness@gentoo.org>
The way the kernel namespaces have been implemented breaks assumptions
udev made regarding uevent sequence numbers. Creating devices in a
namespace "steals" uevents and its sequence numbers from the host. It
confuses the "udevadmin settle" logic, which might block until util a
timeout is reached, even when no uevent is pending.
Remove any assumptions about sequence numbers and deprecate libudev's
API exposing these numbers; none of that can reliably be used anymore
when namespaces are involved.
Signed-off-by: Anthony G. Basile <blueness@gentoo.org>
These commits were authored by
Zbigniew Jędrzejewski-Szmek
Tom Gundersen
Kay Sievers
Lennart Poettering
Shawn Landden
Daniel Buch
Martin Pitt
Karel Zak
Yang Zhiyong
Note: udev_builtin_net_setup_link has *not* been imported. Also
still missing from udev-builtin is udev_builtin_uaccess.
Signed-off-by: Anthony G. Basile <blueness@gentoo.org>
