When threads are disabled, some variables such as tid and tid_bit are
still checked everywhere, the MAX_THREADS_MASK macro is ~0UL while
MAX_THREADS is 1, and the all_threads_mask variable is replaced with a
macro forced to zero. The compiler cannot optimize away all this code
involving checks on tid and tid_bit, and we end up in special cases
where all_threads_mask has to be specifically tested for being zero or
not. It is not even certain the code paths are always equivalent when
testing without threads and with nbthread 1.
Let's change this to make sure we always present a single thread when
threads are disabled, and have the relevant values declared as constants
so that the compiler can optimize all the tests away. Now we have
MAX_THREADS_MASK set to 1, all_threads_mask set to 1, tid set to zero
and tid_bit set to 1. Doing just this has removed 4 kB of code in the
no-thread case.
A few checks for all_threads_mask==0 have been removed since it never
happens anymore.
The purpose is to make sure that all variables which directly depend
on this nbthread argument are set at the right moment. For now only
all_threads_mask needs to be set. It used to be set while calling
thread_sync_init() which is called too late for certain checks. The
same function handles threads and non-threads, which removes the need
for some thread-specific knowledge from cfgparse.c.
While moving Olivier's patch for nbthread==MAX_THREADS in commit
3e12304 ("BUG/MINOR: threads: Handle nbthread == MAX_THREADS.") to
hathreads.c, I missed one place resulting in the computed thread mask
being used as the thread count, which is worse than the initial bug.
Let's fix it properly this time.
This fix must be backported to 1.8 just like the other one.
Add a new pipe, one per thread, so that we can write on it to wake a thread
sleeping in a poller, and use it to wake threads supposed to take care of a
task, if they are all sleeping.
Chunks are only a subset of a buffer (a non-wrapping version with no head
offset). Despite this we still carry a lot of duplicated code between
buffers and chunks. Replacing chunks with buffers would significantly
reduce the maintenance efforts. This first patch renames the chunk's
fields to match the name and types used by struct buffers, with the goal
of isolating the code changes from the declaration changes.
Most of the changes were made with spatch using this coccinelle script :
@rule_d1@
typedef chunk;
struct chunk chunk;
@@
- chunk.str
+ chunk.area
@rule_d2@
typedef chunk;
struct chunk chunk;
@@
- chunk.len
+ chunk.data
@rule_i1@
typedef chunk;
struct chunk *chunk;
@@
- chunk->str
+ chunk->area
@rule_i2@
typedef chunk;
struct chunk *chunk;
@@
- chunk->len
+ chunk->data
Some minor updates to 3 http functions had to be performed to take size_t
ints instead of ints in order to match the unsigned length here.
Now the buffers only contain the header and a pointer to the storage
area which can be anywhere. This will significantly simplify buffer
swapping and will make it possible to map chunks on buffers as well.
The buf_empty variable was removed, as now it's enough to have size==0
and area==NULL to designate the empty buffer (thus a non-allocated head
is the empty buffer by default). buf_wanted for now is indicated by
size==0 and area==(void *)1.
The channels and the checks now embed the buffer's head, and the only
pointer is to the storage area. This slightly increases the unallocated
buffer size (3 extra ints for the empty buffer) but considerably
simplifies dynamic buffer management. It will also later permit to
detach unused checks.
The way the struct buffer is arranged has proven quite efficient on a
number of tests, which makes sense given that size is always accessed
and often first, followed by the othe ones.
Change the way the process groups are set. Indeed setsid() was called
for every processes which caused the worker to have a different process
group than the master.
This patch behave in a better way:
- In daemon mode only, each child do a setsid()
- In master worker + daemon mode, the setsid() is done in the master before
forking the children
- In any foreground mode, we don't do a setsid()
Could be backported in 1.8 but the master-worker mode is mostly used
with systemd which rely on cgroups so that won't affect much people.
The build without threads was once again broken.
This issue was introduced in commit ba86c6c ("MINOR: threads: Be sure to
remove threads from all_threads_mask on exit").
This is exactly the same problem as last time it happened, because of
all_threads_mask not being defined with USE_THREAD=
This must be backported in 1.8
When HAProxy is started with several threads, Each running thread holds a bit in
the bitfiled all_threads_mask. This bitfield is used here and there to check
which threads are registered to take part in a specific processing. So when a
thread exits, it seems normal to remove it from all_threads_mask.
No direct impact could be identified with this right now but it would
be better to backport it to 1.8 as a preventive measure to avoid complex
situations like the one in previous bug.
When HAProxy is shutting down, it exits the polling loop when there is no jobs
anymore (jobs == 0). When there is no thread, it works pretty well, but when
HAProxy is started with several threads, a thread can decide to exit because
jobs variable reached 0 while another one is processing a task (e.g. a
health-check). At this stage, the running thread could decide to request a
synchronization. But because at least one of them has already gone, the others
will wait infinitly in the sync point and the process will never die.
To fix the bug, when the first thread (and only this one) detects there is no
active jobs anymore, it requests a synchronization. And in the sync point, all
threads will check if jobs variable reached 0 to exit the polling loop.
This patch must be backported in 1.8.
The behavior of sigprocmask in an multithreaded environment is
undefined.
The new macro ha_sigmask() calls either pthreads_sigmask() or
sigprocmask() if haproxy was built with thread support or not.
This should be backported to 1.8.
Signals were handled in all threads which caused some signals to be lost
from time to time. To avoid complicated lock system (threads+signals),
we prefer handling the signals in one thread avoiding concurrent access.
The side effect of this bug was that some process were not leaving from
time to time during a reload.
This patch must be backported in 1.8.
There's no real reason to have a specific scheduler for applets anymore, so
nuke it and just use tasks. This comes with some benefits, the first one
being that applets cannot induce high latencies anymore since they share
nice values with other tasks. Later it will be possible to configure the
applets' nice value. The second benefit is that the applet scheduler was
not very thread-friendly, having a big lock around it in prevision of this
change. Thus applet-intensive workloads should now scale much better with
threads.
Some more improvement is possible now : some applets also use a task to
handle timers and timeouts. These ones could now be simplified to use only
one task.
In preparation for thread-specific runqueues, change the task API so that
the callback takes 3 arguments, the task itself, the context, and the state,
those were retrieved from the task before. This will allow these elements to
change atomically in the scheduler while the application uses the copied
value, and even to have NULL tasks later.
Export localpeer as the environment variable $HAPROXY_LOCALPEER,
allowing to use this variable in the configuration file.
It's useful to use this variable in the case of synchronized
configuration between peers.
When doing a seemless reload, while receiving the sockets from the old process
the new process will die if the socket has been bound to a specific
interface.
This happens because the code that tries to parse the informations bogusly
try to set xfer_sock->namespace, while it should be setting wfer_sock->iface.
This should be backported to 1.8.
Krishna Kumar reported a 100% cpu usage with a configuration using
cpu-map and a high number of threads,
Indeed, this minimal configuration to reproduce the issue :
global
nbthread 40
cpu-map auto:1/1-40 0-39
frontend test
bind :8000
This is due to a wrong type in a shift operator (int vs unsigned long int),
causing an endless loop while applying the cpu affinity on threads. The same
issue may also occur with nbproc under FreeBSD. This commit addresses both
cases.
This patch must be backported to 1.8.
Previously, -sf and -sd command line parsing used atol which cannot
detect errors. I had a problem where I was doing -sf "$pid1 $pid2 $pid"
and it was sending the gracefully terminate signal only to the first pid.
The change uses strtol and checks endptr and errno to see if the parsing
worked. It will exit when the pid list is not parsed.
[wt: this should be backported to 1.8]
fd_insert() is currently called just after setting the owner and iocb,
but proceeding like this prevents the operation from being atomic and
requires a lock to protect the maxfd computation in another thread from
meeting an incompletely initialized FD and computing a wrong maxfd.
Fortunately for now all fdtab[].owner are set before calling fd_insert(),
and the first lock in fd_insert() enforces a memory barrier so the code
is safe.
This patch moves the initialization of the owner and iocb to fd_insert()
so that the function will be able to properly arrange its operations and
remain safe even when modified to become lockless. There's no other change
beyond the internal API.
Since only select() and poll() still make use of maxfd, let's move
its computation right there in the pollers themselves, and only
during each fd update pass. The computation doesn't need a lock
anymore, only a few atomic ops. It will be accurate, be done much
less often and will not be required anymore in the FD's fast patch.
This provides a small performance increase of about 1% in connection
rate when using epoll since we get rid of this computation which was
performed under a lock.
A #ifdef/#endif on USE_THREAD was added in the commit 0048dd04 ("MINOR: threads:
Fix build when we're not compiling with threads.") to conditionally define the
start_lock variable, because HA_SPINLOCK_T is only defined when HAProxy is
compiled with threads.
If fact, to do that, we should use the macro __decl_hathreads instead.
If commit 0048dd04 is backported in 1.8, this one can also be backported.
Only declare the start_lock if threads are compiled in, otherwise
HA_SPINLOCK_T won't be defined.
This should be backported to 1.8 when/if
1605c7ae61 is backported.
A missing test causes a write(-1, $PID) to appear in strace output when
in master-worker mode. This is totally harmless though.
This fix must be backported to 1.8.
Marc Fournier reported an interesting case when using threads with the
master-worker mode : sometimes, a listener would have its FD closed
during startup. Sometimes it could even be health checks seeing this.
What happens is that after the threads are created, and the pollers
enabled on each threads, the master-worker pipe is registered, and at
the same time a close() is performed on the write side of this pipe
since the children must not use it.
But since this is replicated in every thread, what happens is that the
first thread closes the pipe, thus releases the FD, and the next thread
starting a listener in parallel gets this FD reassigned. Then another
thread closes the FD again, which this time corresponds to the listener.
It can also happen with the health check sockets if they're started
early enough.
This patch splits the mworker_pipe_register() function in two, so that
the close() of the write side of the FD is performed very early after the
fork() and long before threads are created (we don't need to delay it
anyway). Only the pipe registration is done in the threaded code since
it is important that the pollers are properly allocated for this.
The mworker_pipe_register() function now takes care of registering the
pipe only once, and this is guaranteed by a new surrounding lock.
The call to protocol_enable_all() looks fragile in theory since it
scans the list of proxies and their listeners, though in practice
all threads scan the same list and take the same locks for each
listener so it's not possible that any of them escapes the process
and finishes before all listeners are started. And the operation is
idempotent.
This fix must be backported to 1.8. Thanks to Marc for providing very
detailed traces clearly showing the problem.
fd_cache_num is the number of FDs in the FD cache. It is a global variable. So
it is underoptimized because we may be lead to consider there are waiting FDs
for the current thread in the FD cache while in fact all FDs are assigned to the
other threads. So, in such cases, the polling loop will be evaluated many more
times than necessary.
Instead, we now check if the thread id is set in the bitfield fd_cache_mask.
[wt: it's not exactly a bug, rather a design limitation of the thread
which was not addressed in time for the 1.8 release. It can appear more
often than we initially predicted, when more threads are running than
the number of assigned CPU cores, or when certain threads spend
milliseconds computing crypto keys while other threads spin on
epoll_wait(0)=0]
This patch should be backported to 1.8.
A number of counters have been added at special places helping better
understanding certain bug reports. These counters are maintained per
thread and are shown using "show activity" on the CLI. The "clear
counters" commands also reset these counters. The output is sent as a
single write(), which currently produces up to about 7 kB of data for
64 threads. If more counters are added, it may be necessary to write
into multiple buffers, or to reset the counters.
To backport to 1.8 to help collect more detailed bug reports.
This one allows not to inflate some structures when threads are
disabled. Now struct global is 1.4 kB instead of 33 kB.
Should be backported to 1.8 for ease of backporting of upcoming
patches.
The copy_argv() function lacks a check on '-' to remove the -x, -sf and
-st parameters.
When reloading a master process with a path starting by /st, /sf, or
/x.. the copy_argv() function skipped argv[0] leading to an execvp()
without the binary.
Closing the standard IO FDs (0,1,2) can be troublesome, especially in
the case of the master-worker.
Instead of closing those FDs, they are now pointing to /dev/null which
prevents sending debugging messages to the wrong FDs.
This patch could be backported in 1.8.
This patch makes sure that a frontend socket that gets created after
initialization won't be closed when the master gets re-executed.
When used in daemon mode, the master-worker is closing the FDs 0, 1, 2
after the fork of the children.
When the master was reloading, those FDs were assigned again during the
parsing of the configuration (probably for some listeners), and the
workers were closing them thinking it was the stdio.
This patch must be backported to 1.8.
The number of async fd is computed considering the maxconn, the number
of sides using ssl and the number of engines using async mode.
This patch should be backported on haproxy 1.8
There's a nasty case related to signaling all processes via SIGUSR1.
Since the master process still holds the peers sockets, the old process
trying to connect to the new one to teach it its tables has a risk to
connect to the master instead, which will not do anything, causing the
old process to hang instead of quitting.
This patch ensures we correctly close the peers in the master process
on startup, just like it is done for proxies. Ultimately we would rather
have a complete list of listeners to avoid such issues. But that's a bit
trickier as it would require using unbind_all() and avoiding side effects
the master could cause to other processes (like unlinking unix sockets).
To be backported to 1.8.
As with the call to cpuset_setaffinity(), FreeBSD expects the argument to
pthread_setaffinity_np() to be a cpuset_t, not an unsigned long, so the call
was silently failing.
This should probably be backported to 1.8.
This allows a calling script to show the first startup output and
know when to stop reading from stdout so haproxy can daemonize.
To be backpored to 1.8.
Check if master-worker pipe getenv succeeded, also allow pipe fd 0 as
valid. On FreeBSD in quiet mode the stdin/stdout/stderr are closed
which lets the mworker_pipe to use fd 0 and fd 1. Additionally exit()
upon failure to create or get the master-worker pipe.
This needs to be backported to 1.8.
This patch changes the behavior of the master during the exit of a
worker.
When a worker exits with an error code, for example in the case of a
segfault, all workers are now killed and the master leaves.
If you don't want this behavior you can use the option
"master-worker no-exit-on-failure".
During the migration to the second version of the pools, the new
functions and pool pointers were all called "pool_something2()" and
"pool2_something". Now there's no more pool v1 code and it's a real
pain to still have to deal with this. Let's clean this up now by
removing the "2" everywhere, and by renaming the pool heads
"pool_head_something".
Rename the global variable "proxy" to "proxies_list".
There's been multiple proxies in haproxy for quite some time, and "proxy"
is a potential source of bugs, a number of functions have a "proxy" argument,
and some code used "proxy" when it really meant "px" or "curproxy". It worked
by pure luck, because it usually happened while parsing the config, and thus
"proxy" pointed to the currently parsed proxy, but we should probably not
rely on this.
[wt: some of these are definitely fixes that are worth backporting]
Now, it is possible to bind CPU at the thread level instead of the process level
by defining a thread set in "cpu-map" directives. Thus, its format is now:
cpu-map [auto:]<process-set>[/<thread-set>] <cpu-set>...
where <process-set> and <thread-set> must follow the format:
all | odd | even | number[-[number]]
Having a process range and a thread range in same time with the "auto:" prefix
is not supported. Only one range is supported, the other one must be a fixed
number. But it is allowed when there is no "auto:" prefix.
Because it is possible to define a mapping for a process and another for a
thread on this process, threads will be bound on the intersection of their
mapping and the one of the process on which they are attached. If the
intersection is null, no specific binding will be set for the threads.
While using mmap() to allocate pools for debugging purposes, kill -USR1 caused
libc aborts in deinit() on two calls to free() on proxies' tasks and the global
listener task. The issue comes from the fact that we're using free() to release
a task instead of task_free(), so the task was allocated from a pool and released
using a different method.
This bug has been there since at least 1.5, so a backport is desirable to all
maintained versions.
Since we switched to notify mode in the systemd unit file in commit
d6942c8, haproxy won't start if the daemon keyword is present in the
configuration.
This change makes sure that haproxy remains in foreground when using
systemd mode and adds a note in the documentation.
This patch adds support for `Type=notify` to the systemd unit.
Supporting `Type=notify` improves both starting as well as reloading
of the unit, because systemd will be let known when the action completed.
See this quote from `systemd.service(5)`:
> Note however that reloading a daemon by sending a signal (as with the
> example line above) is usually not a good choice, because this is an
> asynchronous operation and hence not suitable to order reloads of
> multiple services against each other. It is strongly recommended to
> set ExecReload= to a command that not only triggers a configuration
> reload of the daemon, but also synchronously waits for it to complete.
By making systemd aware of a reload in progress it is able to wait until
the reload actually succeeded.
This patch introduces both a new `USE_SYSTEMD` build option which controls
including the sd-daemon library as well as a `-Ws` runtime option which
runs haproxy in master-worker mode with systemd support.
When haproxy is running in master-worker mode with systemd support it will
send status messages to systemd using `sd_notify(3)` in the following cases:
- The master process forked off the worker processes (READY=1)
- The master process entered the `mworker_reload()` function (RELOADING=1)
- The master process received the SIGUSR1 or SIGTERM signal (STOPPING=1)
Change the unit file to specify `Type=notify` and replace master-worker
mode (`-W`) with master-worker mode with systemd support (`-Ws`).
Future evolutions of this feature could include making use of the `STATUS`
feature of `sd_notify()` to send information about the number of active
connections to systemd. This would require bidirectional communication
between the master and the workers and thus is left for future work.
applets_active_queue is the active queue size. It is a global variable. So it is
underoptimized because we may be lead to consider there are active applets for a
thread while in fact all active applets are assigned to the otherthreads. So, in
such cases, the polling loop will be evaluated many more times than necessary.
Instead, we now check if the thread id is set in the bitfield active_applets_mask.
This is specific to threads, no backport is needed.
tasks_run_queue is the run queue size. It is a global variable. So it is
underoptimized because we may be lead to consider there are active tasks for a
thread while in fact all active tasks are assigned to the other threads. So, in
such cases, the polling loop will be evaluated many more times than necessary.
Instead, we now check if the thread id is set in the bitfield active_tasks_mask.
Another change has been made in process_runnable_tasks. Now, we always limit the
number of tasks processed to 200.
This is specific to threads, no backport is needed.
Since the commit cd7879adc ("BUG/MEDIUM: threads: Run the poll loop on the main
thread too"), the log buffers are allocated after the proxies startup. So log
messages produced during this startup was ignored.
To fix the bug, we restore the initialization of these buffers before proxies
startup.
This is specific to threads, no backport is needed.
At the end of the master initialisation, a call to protocol_unbind_all()
was made, in order to close all the FDs.
Unfortunately, this function closes the inherited FDs (fd@), upon reload
the master wasn't able to reload a configuration with those FDs.
The create_listeners() function now store a flag to specify if the fd
was inherited or not.
Replace the protocol_unbind_all() by mworker_cleanlisteners() +
deinit_pollers()
Does not use the deinit() function during a reload, it's dangerous and
might be subject to double free, segfault and hazardous behavior if
it's called twice in the case of a execvp fail.
After execvp fails, the signals were ignored, preventing to try a reload
again. It is now fixed by reaching the top of the mworker_wait()
function once the execvp failed.
When the master worker fail the execvp, it returns the wrong error
"Cannot allocate memory".
We now display the accurate error corresponding to the errno value.
If haproxy is started using the name of the binary only (i.e.
not using a relative or absolute path) the `execv` in
`mworker_reload` fails with `ENOENT`, because it does not
examine the `PATH`:
[WARNING] 315/161139 (7) : Reexecuting Master process
[WARNING] 315/161139 (7) : Cannot allocate memory
[WARNING] 315/161139 (7) : Failed to reexecute the master processs [7]
The error messages are misleading, because the return value of
`execv` is not checked. This should be fixed in a separate commit.
Once this happened the master process ignores any further
signals sent by the administrator.
Replace `execv` with `execvp` to establish the expected
behaviour.
This bug was introduced in commit 73b85e75b3.
At a number of places, bitmasks are used for process affinity and to map
listeners to processes. Every time 1UL<<(relative_pid-1) is used. Let's
create a "pid_bit" variable corresponding to this value to clean this up.
The first pid in the pidfile is now the parent, it's more convenient for
supervising the processus.
You can now reload haproxy in master-worker mode with convenient command
like: kill -USR2 $(head -1 /tmp/haproxy.pid)
This patch introduces a new struct conn_stream. It's the stream-side of
a multiplexed connection. A pool is created and destroyed on exit. For
now the conn_streams are not used at all.
There was a flaw in the way the threads was created. the main one was just used
to create all the others and just wait to exit. Now, it is used to run a poll
loop. So we only create nbthread-1 threads.
This also fixes a bug about the compression filter when there is only 1 thread
(nbthread == 1 or no threads support). The bug was in the way thread-local
resources was initialized. per-thread init/deinit callbacks were never called
for the main process. So, with nthread set to 1, some buffers remained
uninitialized.
By default, no affinity is set for threads. To bind threads on CPU, you must
define a "thread-map" in the global section. The format is the same than the
"cpu-map" parameter, with a small difference. The process number must be
defined, with the same format than cpu-map ("all", "even", "odd" or a number
between 1 and 31/63).
A thread will be bound on the intersection of its mapping and the one of the
process on which it is attached. If the intersection is null, no specific bind
will be set for the thread.
A lock for LB parameters has been added inside the proxy structure and atomic
operations have been used to update server variables releated to lb.
The only significant change is about lb_map. Because the servers status are
updated in the sync-point, we can call recalc_server_map function synchronously
in map_set_server_status_up/down function.
This list is used to save changes on the servers state. So when serveral threads
are used, it must be locked. The changes are then applied in the sync-point. To
do so, servers_update_status has be moved in the sync-point. So this is useless
to lock it at this step because the sync-point is a protected area by iteself.
Now, each proxy contains a lock that must be used when necessary to protect
it. Moreover, all proxy's counters are now updated using atomic operations.
2 global locks have been added to protect, respectively, the run queue and the
wait queue. And a process mask has been added on each task. Like for FDs, this
mask is used to know which threads are allowed to process a task.
For many tasks, all threads are granted. And this must be your first intension
when you create a new task, else you have a good reason to make a task sticky on
some threads. This is then the responsibility to the process callback to lock
what have to be locked in the task context.
Nevertheless, all tasks linked to a session must be sticky on the thread
creating the session. It is important that I/O handlers processing session FDs
and these tasks run on the same thread to avoid conflicts.
Many changes have been made to do so. First, the fd_updt array, where all
pending FDs for polling are stored, is now a thread-local array. Then 3 locks
have been added to protect, respectively, the fdtab array, the fd_cache array
and poll information. In addition, a lock for each entry in the fdtab array has
been added to protect all accesses to a specific FD or its information.
For pollers, according to the poller, the way to manage the concurrency is
different. There is a poller loop on each thread. So the set of monitored FDs
may need to be protected. epoll and kqueue are thread-safe per-se, so there few
things to do to protect these pollers. This is not possible with select and
poll, so there is no sharing between the threads. The poller on each thread is
independant from others.
Finally, per-thread init/deinit functions are used for each pollers and for FD
part for manage thread-local ressources.
Now, you must be carefull when a FD is created during the HAProxy startup. All
update on the FD state must be made in the threads context and never before
their creation. This is mandatory because fd_updt array is thread-local and
initialized only for threads. Because there is no pollers for the main one, this
array remains uninitialized in this context. For this reason, listeners are now
enabled in run_thread_poll_loop function, just like the worker pipe.
The function sync_poll_loop is called at the end of each loop inside
run_poll_loop function. It is a protected area where all threads have a chance
to execute tricky tasks with the warranty that no concurrent access is
possible. Of course, it comes with a cost because all threads must be
syncrhonized. So changes must be uncommon.
[WARNING] For now, HAProxy is not thread-safe, so from this commit, it will be
broken for a while, when compiled with threads.
When nbthread parameter is greater than 1, HAProxy will create the corresponding
number of threads. If nbthread is set to 1, nothing should be done. So if there
are concurrency issues (and be sure there will be, unfortunatly), an obvious
workaround is to disable the multithreading...
Each created threads will run a polling loop. So, in a certain way, it is pretty
similar to the nbproc mode ("outside" the bugs and the lock
contention). Nevertheless, there are an init and a deinit steps for each thread
to deal with per-thread allocation.
Each thread has a tid (thread-id), numbered from 0 to (nbtread-1). It is used in
many place to do bitwise operations or to improve debugging information.
hap_register_per_thread_init and hap_register_per_thread_deinit functions has
been added to register functions to do, for each thread, respectively, some
initialization and deinitialization. These functions are added in the global
lists per_thread_init_list and per_thread_deinit_list.
These functions are called only when HAProxy is started with more than 1 thread
(global.nbthread > 1).
This is a huge patch with many changes, all about the DNS. Initially, the idea
was to update the DNS part to ease the threads support integration. But quickly,
I started to refactor some parts. And after several iterations, it was
impossible for me to commit the different parts atomically. So, instead of
adding tens of patches, often reworking the same parts, it was easier to merge
all my changes in a uniq patch. Here are all changes made on the DNS.
First, the DNS initialization has been refactored. The DNS configuration parsing
remains untouched, in cfgparse.c. But all checks have been moved in a post-check
callback. In the function dns_finalize_config, for each resolvers, the
nameservers configuration is tested and the task used to manage DNS resolutions
is created. The links between the backend's servers and the resolvers are also
created at this step. Here no connection are kept alive. So there is no needs
anymore to reopen them after HAProxy fork. Connections used to send DNS queries
will be opened on demand.
Then, the way DNS requesters are linked to a DNS resolution has been
reworked. The resolution used by a requester is now referenced into the
dns_requester structure and the resolution pointers in server and dns_srvrq
structures have been removed. wait and curr list of requesters, for a DNS
resolution, have been replaced by a uniq list. And Finally, the way a requester
is removed from a DNS resolution has been simplified. Now everything is done in
dns_unlink_resolution.
srv_set_fqdn function has been simplified. Now, there is only 1 way to set the
server's FQDN, independently it is done by the CLI or when a SRV record is
resolved.
The static DNS resolutions pool has been replaced by a dynamoc pool. The part
has been modified by Baptiste Assmann.
The way the DNS resolutions are triggered by the task or by a health-check has
been totally refactored. Now, all timeouts are respected. Especially
hold.valid. The default frequency to wake up a resolvers is now configurable
using "timeout resolve" parameter.
Now, as documented, as long as invalid repsonses are received, we really wait
all name servers responses before retrying.
As far as possible, resources allocated during DNS configuration parsing are
releases when HAProxy is shutdown.
Beside all these changes, the code has been cleaned to ease code review and the
doc has been updated.
In order to prepare multi-thread development, code was re-worked
to propagate changes asynchronoulsy.
Servers with pending status changes are registered in a list
and this one is processed and emptied only once 'run poll' loop.
Operational status changes are performed before administrative
status changes.
In a case of multiple operational status change or admin status
change in the same 'run poll' loop iteration, those changes are
merged to reach only the targeted status.
The server state and weight was reworked to handle
"pending" values updated by checks/CLI/LUA/agent.
These values are commited to be propagated to the
LB stack.
In further dev related to multi-thread, the commit
will be handled into a sync point.
Pending values are named using the prefix 'next_'
Current values used by the LB stack are named 'cur_'
This string is used in sample fetches so it is safe to use a preallocated trash
chunk instead of a buffer dynamically allocated during HAProxy startup.
First, this variable does not need to be publicly exposed because it is only
used by stick_table functions. So we declare it as a global static in
stick_table.c file. Then, it is useless to use a pointer. Using a plain struct
variable avoids any dynamic allocation.
swap_buffer is a global variable only used by buffer_slow_realign. So it has
been moved from global.h to buffer.c and it is allocated by init_buffer
function. deinit_buffer function has been added to release it. It is also used
to destroy the buffers' pool.
During the configuration parsing, log buffers are reallocated when
global.max_syslog_len is updated. This can be done serveral time. So, instead of
doing it serveral time, we do it only once after the configuration parsing.
Now, we use init_log_buffers and deinit_log_buffers to, respectively, initialize
and deinitialize log buffers used for syslog messages.
These functions have been introduced to be used by threads, to deal with
thread-local log buffers.
Trash buffers are reallocated when "tune.bufsize" parameter is changed. Here, we
just move the realloc after the configuration parsing.
Given that the config parser doesn't rely on the trash size, it should be
harmless.
Now, we use init_trash_buffers and deinit_trash_buffers to, respectively,
initialize and deinitialize trash buffers (trash, trash_buf1 and trash_buf2).
These functions have been introduced to be used by threads, to deal with
thread-local trash buffers.
Use a cpuset_t instead of assuming the cpu mask is an unsigned long.
This should fix setting the CPU affinity on FreeBSD >= 11.
This patch should be backported to stable releases.
As mentionned in commit cf4e496c9 ("BUG/MEDIUM: build without openssl broken"),
commit 872f9c213 ("MEDIUM: ssl: add basic support for OpenSSL crypto engine")
broke the build without openssl support. But the former did only fix it when
openssl is not enabled, but not when it's not installed on the system :
In file included from src/haproxy.c:112:
include/proto/ssl_sock.h:24:25: openssl/ssl.h: No such file or directory
In file included from src/haproxy.c:112:
include/proto/ssl_sock.h:45: error: syntax error before "SSL_CTX"
include/proto/ssl_sock.h:75: error: syntax error before '*' token
include/proto/ssl_sock.h:75: warning: type defaults to `int' in declaration of `ssl_sock_create_cert'
include/proto/ssl_sock.h:75: warning: data definition has no type or storage class
include/proto/ssl_sock.h:76: error: syntax error before '*' token
include/proto/ssl_sock.h:76: warning: type defaults to `int' in declaration of `ssl_sock_get_generated_cert'
include/proto/ssl_sock.h:76: warning: data definition has no type or storage class
include/proto/ssl_sock.h:77: error: syntax error before '*' token
Now we also surround the include with #ifdef USE_OPENSSL to fix this. No
backport is needed since openssl async engines were not backported.
When several stick-tables were configured with several peers sections,
only a part of them could be synchronized: the ones attached to the last
parsed 'peers' section. This was due to the fact that, at least, the peer I/O handler
refered to the wrong peer section list, in fact always the same: the last one parsed.
The fact that the global peer section list was named "struct peers *peers"
lead to this issue. This variable name is dangerous ;).
So this patch renames global 'peers' variable to 'cfg_peers' to ensure that
no such wrong references are still in use, then all the functions wich used
old 'peers' variable have been modified to refer to the correct peer list.
Must be backported to 1.6 and 1.7.
When starting the master worker with -sf or -st, the PIDs will be reused
on the next reload, which is a problem if new processes on the system
took those PIDs.
This patch ensures that we don't register old PIDs in the reload system
when launching the master worker.
Don't copy the -x argument anymore in copy_argv() since it's already
allocated in mworker_reload().
Make the copy_argv() more consistent when used with multiple arguments
to strip.
It prevents multiple -x on reload, which is not supported.
