These ones were still in cfgparse.c but they're not specific to the
config at all and may actually be used even when parsing cpu list
entries in /sys. Better move them where they can be reused.
cpu_map is 8.2kB/entry and there's one such entry per group, that's
~520kB total. In addition, the init code is still in haproxy.c enclosed
in ifdefs. Let's make this a dynamically allocated array in the cpuset
code and remove that init code.
Later we may even consider reallocating it once the number of threads
and groups is known, in order to shrink it a little bit, as the typical
setup with a single group will only need 8.2kB, thus saving half a MB
of RAM. This would require that the upper bound is placed in a variable
though.
Till now the CPUs that were bound were only retrieved in
thread_cpus_enabled() in order to count the number of CPUs allowed,
and it relied on arch-specific code.
Let's slightly arrange this into ha_cpuset_detect_bound() that
reuses the ha_cpuset struct and the accompanying code. This makes
the code much clearer without having to carry along some arch-specific
stuff out of this area.
Note that the macos-specific code used in thread.c to only count
online CPUs but not retrieve a mask, so for now we can't infer
anything from it and can't implement it.
In addition and more importantly, this function is reliable in that
it will only return a value when the detection is accurate, and will
not return incomplete sets on operating systems where we don't have
an exact list, such as online CPUs.
Since we'll soon want to adjust the "thread-groups" degree of freedom
based on the presence of cpu-map, we first need to be able to detect
if cpu-map was used. This function scans all cpu-map sets to detect if
any is present, and returns true accordingly.
The principle remains the same, but instead of having a single process
and ignoring extra ones, now we set the affinity masks for the respective
threads of all groups.
The doc was updated with a few extra examples.
The man page indicates that CPU_AND() and CPU_ASSIGN() take a variable,
not a const on the source, even though it doesn't make much sense. But
with older libcs, this triggers a build warning:
src/cpuset.c: In function 'ha_cpuset_and':
src/cpuset.c:53: warning: initialization discards qualifiers from pointer target type
src/cpuset.c: In function 'ha_cpuset_assign':
src/cpuset.c:101: warning: initialization discards qualifiers from pointer target type
Better stick stricter to the documented API as this is really harmless
here. There's no need to backport it (unless build issues are reported,
which is quite unlikely).
"f(void)" is the correct and preferred form for a function taking no
argument, while some places use the older "f()". These were reported
by clang's -Wmissing-prototypes, for example:
src/cpuset.c:111:5: warning: no previous prototype for function 'ha_cpuset_size' [-Wmissing-prototypes]
int ha_cpuset_size()
include/haproxy/cpuset.h:42:5: note: this declaration is not a prototype; add 'void' to make it a prototype for a zero-parameter function
int ha_cpuset_size();
^
void
This aggregate patch fixes this for the following functions:
ha_backtrace_to_stderr(), ha_cpuset_size(), ha_panic(), ha_random64(),
ha_thread_dump_all_to_trash(), get_exec_path(), check_config_validity(),
mworker_child_nb(), mworker_cli_proxy_(create|stop)(),
mworker_cleantasks(), mworker_cleanlisteners(), mworker_ext_launch_all(),
mworker_reload(), mworker_(env|proc_list)_to_(proc_list|env)(),
mworker_(un|)block_signals(), proxy_adjust_all_maxconn(),
proxy_destroy_all_defaults(), get_tainted(),
pool_total_(allocated|used)(), thread_isolate(_full|)(),
thread(_sync|)_release(), thread_harmless_till_end(),
thread_cpu_mask_forced(), dequeue_all_listeners(), next_timer_expiry(),
wake_expired_tasks(), process_runnable_tasks(), init_acl(),
init_buffer(), (de|)init_log_buffers(), (de|)init_pollers(),
fork_poller(), pool_destroy_all(), pool_evict_from_local_caches(),
pool_total_failures(), dump_pools_to_trash(), cfg_run_diagnostics(),
tv_init_(process|thread)_date(), __signal_process_queue(),
deinit_signals(), haproxy_unblock_signals()
Move cpu_map structure outside of the global struct to a global
variable defined in cpuset.c compilation unit. This allows to reorganize
the includes without having to define _GNU_SOURCE everywhere for the
support of the cpu_set_t.
This fixes the compilation with musl libc, most notably used for the
alpine based docker image.
This fixes the github issue #1235.
No need to backport as this feature is new in the current
2.4-dev.
This module can be used to manipulate a cpu sets in a platform agnostic
way. Use the type cpu_set_t/cpuset_t if available on the platform, or
fallback to unsigned long, which limits de facto the maximum cpu index
to LONGBITS.
