Commit 4528611 ("MEDIUM: mworker: store the leaving state of a process")
introduced a bug in the mworker_env_to_proc_list() function.
This is very unlikely to occur since the PID should always be assigned.
It can probably happen if the environment variable is corrupted.
No backport needed.
This patch implements a new global parameter for the master-worker mode.
When setting the mworker-max-reloads value, a worker receive a SIGTERM
if its number of reloads is greater than this value.
task_delete() was never used without calling task_free() just after, and
task_free() was only used on error pathes to destroy a just-created task,
so merge them into task_destroy(), that will remove the task from the
wait queue, and make sure the task is either destroyed immediately if it's
not in the run queue, or destroyed when it's supposed to run.
Since the fix "BUG/MINOR: mworker: don't exit with an ambiguous value"
we are leaving with a EXIT_SUCCESS upon a SIGINT.
We still need to quit with a SIGINT when a worker leaves with a SIGINT.
This is done this way because vtest expect a 130 during the process
stop, haproxy without mworker returns a 130, so it should be the same in
mworker mode.
This should be backported in 1.9, with the previous patch ("BUG/MINOR:
mworker: don't exit with an ambiguous value").
Code has moved, mworker_catch_sigchld() is in haproxy.c.
When the sigchld handler is called and waitpid() returns -1,
the behavior of waitpid() with the status variable is undefined.
It is not a good idea to exit with the value contained in it.
Since this exit path does not use the exitcode variable, it means that
this is an expected and successful exit.
This should be backported in 1.9, code has moved,
mworker_catch_sigchld() is in haproxy.c.
Commit 3f12887 ("MINOR: mworker: don't use children variable anymore")
introduced a regression.
The previous behavior was to send a signal to every children, whether or
not they are former children. Instead of this, we only send a signal to
the current children, so we don't try to kill -INT or -TERM all
processes during a reload.
No backport needed.
Since the introduction of the options field, we can use it to store the
type of process.
type = 'm' is replaced by PROC_O_TYPE_MASTER
type = 'w' is replaced by PROC_O_TYPE_WORKER
type = 'e' is replaced by PROC_O_TYPE_PROG
The old values are still used in the HAPROXY_PROCESSES environment
variable to pass the information during a reload.
Previously we were assuming than a process was in a leaving state when
its number of reload was greater than 0. With mworker programs it's not
the case anymore so we need to store a leaving state.
This patch implements the external binary support in the master worker.
To configure an external process, you need to use the program section,
for example:
program dataplane-api
command ./dataplane_api
Those processes are launched at the same time as the workers.
During a reload of HAProxy, those processes are dealing with the same
sequence as a worker:
- the master is re-executed
- the master sends a USR1 signal to the program
- the master launches a new instance of the program
During a stop, or restart, a SIGTERM is sent to the program.
The children variable is still used in haproxy, it is not required
anymore since we have the information about the current workers in the
mworker_proc linked list.
The oldpids array is also replaced by this linked list when we
generated the arguments for the master reexec.