The TX packet refcounting had come with the multithreading support but not only.
It is very useful to ease the management of the memory allocated for TX packets
with TX frames attached to. At some locations of the code we have to move TX
frames from a packet to a new one during retranmission when the packet has been
deemed as lost or not. When deemed lost the memory allocated for the paquet must
be released contrary to when its frames are retransmitted when probing (PTO).
For now on, thanks to this patch we handle the TX packets memory this way. We
increment the packet refcount when:
- we insert it in its packet number space tree,
- we attache an ack-eliciting frame to it.
And reciprocally we decrement this refcount when:
- we remove an ack-eliciting frame from the packet,
- we delete the packet from its packet number space tree.
Note that an optimization WOULD NOT be to fully reuse (without releasing its
memorya TX packet to retransmit its contents (its ack-eliciting frames). Its
information (timestamp, in flight length) to be processed by packet loss detection
and the congestion control.
When building a packet with an ACK frame, we store the largest acknowledged
packet number sent in this frame in the packet (quic_tx_packet struc).
When receiving an ack for such a packet we can purge the tree of acknowledged
packet number ranges from the range sent before this largest acknowledged
packet number.
This struct member stores the largest acked packet number which was received. It
is used to build (TX) packet. But this is confusing to store it in the tx packet
of the packet number space structure even if it is used to build and transmit
packets.
There was free_act_rules() that frees all rules from a head but nothing
to free a single rule. Currently some rulesets partially free their own
rules on parsing error, and we're seeing some regtests emit errors under
ASAN because of this.
Let's first extract the code to free a rule into its own function so
that it becomes possible to use it on a single rule.
Log servers are a real mess because:
- entries are duplicated using memcpy() without their strings being
reallocated, which results in these ones not being freeable every
time.
- a new field, ring_name, was added in 2.2 by commit 99c453df9
("MEDIUM: ring: new section ring to declare custom ring buffers.")
but it's never initialized during copies, causing the same issue
- no attempt is made at freeing all that.
Of course, running "haproxy -c" under ASAN quickly notices that and
dumps a core.
This patch adds the missing strdup() and initialization where required,
adds a new free_logsrv() function to cleanly free() such a structure,
calls it from the proxy when iterating over logsrvs instead of silently
leaking their file names and ring names, and adds the same logsrv loop
to the proxy_free_defaults() function so that we don't leak defaults
sections on exit.
It looks a bit entangled, but it comes as a whole because all this stuff
is inter-dependent and was missing.
It's probably preferable not to backport this in the foreseable future
as it may reveal other jokes if some obscure parts continue to memcpy()
the logsrv struct.
The BUG_ON_HOT() test condition added to b_peek_varint() by commit
8873b85bd ("DEBUG: buf: add BUG_ON_HOT() to most buffer management
functions") was wrong as <data> in this function is not b->data,
so that was triggering during live dumps of H2 traces on the CLI
when built with -DDEBUG_STRICT=2. No backport is needed.
The current implementation of STREAM frames emission has some
limitation. Most notably when we cannot sent all frames in a single
qc_send run.
In this case, frames are left in front of the MUX list. It will be
re-send individually before other frames, possibly another frame from
the same STREAM with new data. An opportunity to merge the frames is
lost here.
This method is now improved. If a frame cannot be send entirely, it is
discarded. On the next qc_send run, we retry to send to this position. A
new field qcs.sent_offset is used to remember this. A new frame list is
used for each qc_send.
The impact of this change is not precisely known. The most notable point
is that it is a more logical method of emission. It might also improve
performance as we do not keep old STREAM frames which might delay other
streams.
Implement a new MUX function qcc_notify_send. This function must be
called by the transport layer to confirm the sending of STREAM data to
the MUX.
For the moment, the function has no real purpose. However, it will be
useful to solve limitations on push frame and implement the flow
control.
The aim of the idle timeout is to silently closed the connection after a period
of inactivity depending on the "max_idle_timeout" transport parameters advertised
by the endpoints. We add a new task to implement this timer. Its expiry is
updated each time we received an ack-eliciting packet, and each time we send
an ack-eliciting packet if no other such packet was sent since we received
the last ack-eliciting packet. Such conditions may be implemented thanks
to QUIC_FL_CONN_IDLE_TIMER_RESTARTED_AFTER_READ new flag.
This packet number space flags were defined with the same value because
defined at different places in the file. Assemble them at the same location
with different values.
This bug could unvalidate the peer address after it was validated
during the handshake leading to the anti-amplication limit to be
enabled again after having been disabled. The situation could not
be unblocked (deadlock).
There is no need to use such a reference counter anymore since the QUIC
connections are always handled by the same thread.
quic_conn_drop() is removed. Its code is merged into quic_conn_release().
When we store the remote transport parameters, we compute the maximum idle
timeout for the connection which is the minimum of the two advertised
max_idle_timeout transport parameter values if both have non-null values, or the
maximum if one of the value is set and non-null.
When a tcp-{request,response} content or http-request/http-response
rule delivers a final verdict (deny, accept, redirect etc), the last
evaluated one will now be recorded in the stream. The purpose is to
permit to log the last one that performed a final action. For now
the log is not produced.
The server_id_hdr_name is already processed as an ist in various locations lets
also just store it as such.
see 0643b0e7e ("MINOR: proxy: Make `header_unique_id` a `struct ist`") for a
very similar past commit.
The orgto_hdr_name is already processed as an ist in `http_process_request`,
lets also just store it as such.
see 0643b0e7e ("MINOR: proxy: Make `header_unique_id` a `struct ist`") for a
very similar past commit.
The fwdfor_hdr_name is already processed as an ist in `http_process_request`,
lets also just store it as such.
see 0643b0e7e ("MINOR: proxy: Make `header_unique_id` a `struct ist`") for a
very similar past commit.
The monitor_uri is already processed as an ist in `http_wait_for_request`, lets
also just store it as such.
see 0643b0e7e ("MINOR: proxy: Make `header_unique_id` a `struct ist`") for a
very similar past commit.
Supporting kFreebsd previously led to FreeBSD (< 14) build breakage:
In file included from src/cpuset.c:5:
In file included from include/haproxy/cpuset.h:4:
include/haproxy/cpuset-t.h:46:2: error: unknown type name 'cpu_set_t'; did you mean 'cpuset_t'?
CPUSET_REPR cpuset;
^~~~~~~~~~~
cpuset_t
include/haproxy/cpuset-t.h:21:22: note: expanded from macro 'CPUSET_REPR'
# define CPUSET_REPR cpu_set_t
^
Around limits for QUIC integer encoding, this functions could return
wrong values which lead to qc_build_frms() to prepare wrong CRYPTO (less chances)
or STREAM frames (more chances). qc_do_build_pkt() could build wrong packets
with bad CRYPTO/STREAM frames which could not be decoded by the peer.
In such a case ngtcp2 closes the connection with an ENCRYPTION_ERROR error
in a transport CONNECTION_CLOSE frame.
This function returns the maximum integer which may be encoded with a number of
bytes passed as parameter. Useful to precisely compute the number of bytes which
may used to fulfill a buffer with lengths as QUIC enteger encoded prefixes for the
number of following bytes.
When in congestion avoidance state and when acknowledging an <acked> number bytes
we must increase the congestion window by at most one datagram (<path->mtu>)
by congestion window. So thanks to this patch we apply a ratio to the current
number of acked bytes : <acked> * <path->mtu> / <cwnd>.
So, when <cwnd> bytes are acked we precisely increment <cwnd> by <path->mtu>.
Furthermore we take into an account the number of remaining acknowledged bytes
each time we increment the window by <acked> storing their values in the algorithm
struct state (->remain_acked) so that it might be take into an account at the
next ACK event.
This function returns the remaining number of bytes which can be sent on the
network before fulfilling the congestion window. There is a counter for
the number of prepared data and another one for the really in flight number
of bytes (in_flight). These variable have been mixed up.
Since the persistent congestion detection is done out of the congestion
controllers, there is no need to pass them information through quic_cc_event struct.
We remove its useless members. Also remove qc_cc_loss_event() which is no more used.
We establish the persistent congestion out of any congestion controller
to improve the algorithms genericity. This path characteristic detection may
be implemented regarless of the underlying congestion control algorithm.
Send congestion (loss) event using directly quic_cc_event(), so without
qc_cc_loss_event() wrapper function around quic_cc_event().
Take the opportunity of this patch to shorten "newest_time_sent" member field
of quic_cc_event to "time_sent".
We want to be able to make the congestion controllers re-enter the slow
start state outside of the congestion controllers themselves. So,
we add a callback ->slow_start() to do so.
Define this callback for NewReno algorithm.
kFreeBSD needs to be treated as a distinct target from FreeBSD
since the underlying system libc is the GNU one. Thus, relying
only on __GLIBC__ no longer suffice.
- freebsd-glibc new target, key difference is including crypt.h
and linking to libdl like linux.
- cpu affinity available but the api is still the FreeBSD's.
- enabling auxiliary data access only for Linux.
Patch based on preliminary work done by @bigon.
closes#1555
Implement the locally flow-control streams limit for opened
bidirectional streams. Add a counter which is used to count the total
number of closed streams. If this number is big enough, emit a
MAX_STREAMS frame to increase the limit of remotely opened bidirectional
streams.
This is the first commit to implement QUIC flow-control. A series of
patches should follow to complete this.
This is required to be able to handle more than 100 client requests.
This should help to validate the Multiplexing interop test.
Modify the STREAM emission in qc_send. Use the new transport function
qc_send_app_pkts to directly send the list of constructed frames. This
allows to remove the tasklet wakeup on the quic_conn and should reduce
the latency.
If not all frames are send after the transport call, subscribe the MUX
on the lower layer to be able to retry. Currently there is a bug because
the transport layer does not retry to send frames in excess after a
successful sendto. This might cause the transfer to be interrupted.
Define two new unions in the qcc structure named 'lfctl' and 'rfctl'.
For the moment they are empty. They will be completed to store the
initial and current level for flow-control on the local and remote side.
Improve the functions used to detect the stream characteristics :
uni/bidirectional and local/remote initiated.
Most notably, these functions are now designed to work transparently for
a MUX in the frontend or backend side. For this, we use the connection
to determine the current MUX side. This will be useful if QUIC is
implemented on the server side.
Since QUIC accept handling has been improved, the MUX is initialized
after the handshake completion. Thus its safe to access transport
parameters in qc_init via the quic_conn.
Remove quic_mux_transport_params_update which was called by the
transport for the MUX. This improves the architecture by removing a
direct call from the transport to the MUX.
The deleted function body is not transfered to qc_init because this part
will change heavily in the near future when implementing the
flow-control.
As reported by Tim in issue #1428, our sources are clean, there are
just a few files with a few rare non-ASCII chars for the paragraph
symbol, a few typos, or in Fred's name. Given that Fred already uses
the non-accentuated form at other places like on the public list,
let's uniformize all this and make sure the code displays equally
everywhere.
This is the pool equivalent of commit 97ea9c49f ("BUG/MEDIUM: fd: always
align fdtab[] to 64 bytes"). After a careful code review, it happens that
the pool heads are the other structures allocated with malloc/calloc that
claim to be aligned to a size larger than what the allocator can offer.
While no issue was reported on them, no memset() is performed and no type
is large, this is a problem waiting to happen, so better fix it. In
addition, it's relatively easy to do by storing the allocation address
inside the pool_head itself and use it at free() time. Finally, threads
might benefit from the fact that the caches will really be aligned and
that there will be no false sharing.
This should be backported to all versions where it applies easily.
Many inline functions involve some BUG_ON() calls and because of the
partial complexity of the functions, they're not inlined anymore (e.g.
co_data()). The reason is that the expression instantiates the message,
its size, sometimes a counter, then the atomic OR to taint the process,
and the back trace. That can be a lot for an inline function and most
of it is always the same.
This commit modifies this by delegating the common parts to a dedicated
function "complain()" that takes care of updating the counter if needed,
writing the message and measuring its length, and tainting the process.
This way the caller only has to check a condition, pass a pointer to the
preset message, and the info about the type (bug or warn) for the tainting,
then decide whether to dump or crash. Note that this part could also be
moved to the function but resulted in complain() always being at the top
of the stack, which didn't seem like an improvement.
Thanks to these changes, the BUG_ON() calls do not result in uninlining
functions anymore and the overall code size was reduced by 60 to 120 kB
depending on the build options.
This one is referenced in initcalls by its pointer, it makes no sense
to declare it inline. At best it causes function duplication, at worst
it doesn't build on older compilers.
This one is referenced in initcalls by its pointer, it makes no sense
to declare it inline. At best it causes function duplication, at worst
it doesn't build on older compilers.
The 3 functions http_{req,res,after_res}_keywords_register() are
referenced in initcalls by their pointer, it makes no sense to declare
them inline. At best it causes function duplication, at worst it doesn't
build on older compilers.
This one is referenced in initcalls by its pointer, it makes no sense
to declare it inline. At best it causes function duplication, at worst
it doesn't build on older compilers.
gcc 6 continues its saga with excessive reports of null-deref warnings.
This time it was in the IS_HTX_CS() macro. Let's use __cs_conn() after
cs_conn() was checked.
Do not distinguish the direction (TX/RX) when settings TLS secrets flags.
There is not such a distinction in the RFC 9001.
Assemble them at the same level: at the upper context level.
Wakeup asap the timer task when setting its timer in the past.
Take also the opportunity of this patch to make simplify quic_pto_pktns():
calling tick_first() is useless here to compare <lpto> with <tmp_pto>.
We had several warnings when building haproxy 2.5.4 with
old openssl 1.0.1e. This version of openssl is the latest
available in EOL centos 6.
include/haproxy/openssl-compat.h:157:51: \
warning: "LIBRESSL_VERSION_NUMBER" is not defined
This patch fixed the build. It changes the #if condition,
as done in other similar parts of openssl-compat.h.
Reorganize the Rx path for STREAM frames on bidirectional streams. A new
function qcc_recv is implemented on the MUX. It will handle the STREAM
frames copy and offset calculation from transport to MUX.
Another function named qcc_decode_qcs from the MUX can be called by
transport each time new STREAM data has been copied.
The architecture is now cleaner with the MUX layer in charge of parsing
the STREAM frames offsets. This is required to be able to implement the
flow-control on the MUX layer.
Note that as a convenience, a STREAM frame is not partially copied to
the MUX buffer. This simplify the implementation for the moment but it
may change in the future to optimize the STREAM frames handling.
For the moment, only bidirectional streams benefit from this change. In
the future, it may be extended to unidirectional streams to unify the
STREAM frames processing.
FIN flag on a STREAM frame was not detected if the frame was previously
buffered on qcs.rx.frms before being handled.
To fix this, copy the fin field from the quic_stream instance to
quic_rx_strm_frm. This is required to properly notify the FIN flag on
qc_treat_rx_strm_frms for the MUX layer.
Without this fix, the request channel might be left opened after the
last STREAM frame reception if there is out-of-order frames on the Rx
path.
This flag is set when the STREAM frame with FIN set has been received on
a qcs instance. For now, this is only used as a BUG_ON guard to prevent
against multiple frames with FIN set. It will also be useful when
reorganize the RX path and move some of its code in the mux.
The new macro was introduced with commit 86bcc5308 ("DEBUG: implement 4
levels of choices between warn and crash.") but some older compilers can
complain that we test the value when the macro is not defined despite
having already been checked in a previous #if directive. Let's just
repeat the test for the definition.
693b23bb1 ("MEDIUM: tree-wide: Use unsafe conn-stream API when it is
relevant") introduced a regression in DEBUG_STRICT mode because some BUG_ON
conditions were inverted. It should ok now.
In addition, ALREADY_CHECKED macro was removed from appctx_wakeup() function
because it is useless now.
This way si_*_recv() and si_*_sned() API are defined the same
way. si_sync_snd/si_sync_recv are both exported and defined in the C
file. And si_cs_send/si_cs_recv are private and only used by
stream-interface internals.
The unsafe conn-stream API (__cs_*) is now used when we are sure the good
endpoint or application is attached to the conn-stream. This avoids compiler
warnings about possible null derefs. It also simplify the code and clear up
any ambiguity about manipulated entities.
Depending on the context, we know the endpoint or the application attached
to the conn_stream is defined and we know its type. However, having
accessors testing the endpoint or the application may lead the compiler to
report possible null derefs here and there. The alternative is to add
useless tests or use ALREAD_CHECKED/DISGUISE macros. It is tedious and
inelegant.
So now, similarily to the ob API, the safe API, testing
endpoint/application, relies on an unsafe one (same name prefixed with
'__'). This way, any caller may use the unsafe API when it is relevant.
In addition, there is no reason to test the conn-stream itself. It is the
caller responsibility to be sure there is a conn-stream to get its endpoint
or its application. And most of type, we are sure to have a conn-stream.
A few functions such as c_adv(), c_rew(), co_set_data() or co_skip() got a
BUG_ON_HOT() to make sure they're not used to push more data than available
in the buffer. Note that with HTX the margin can be high and will less easily
trigger, but the goal is to detect a misuse early enough.
co_data() should never be called with a wrong c->output. At least it never
happens in regtests, but we're adding a CHECK_IF_HOT() there to avoid crashing
but report it if it ever happened when the hot path checks are enabled.
The use of co_set_data() should be strictly limited to setting the amount
of existing data to be transmitted. It ought not be used to decrement the
output after the data have left the buffer, because doing so involves
performing incorrect calculations using co_data() that still comprises
data that are not in the buffer anymore. Let's use c_rew() for this, which
is made exactly for this purpose, i.e. decrement c->output by as much as
requested. This is cleaner, faster, and will permit stricter checks.
A number of tests are now performed in low-level buffer management
functions to verify that we're not appending data to a full buffer
for example, or that the buffer passed in argument is consistent in
that its data don't outweigh its size. The few functions that already
involve memcpy() or memmove() instead got a BUG_ON() that will always
be enabled, since the overhead remains minimalist.
The buffer ring management functions br_* were all stuffed with BUG_ON()
statements that never triggered and that are on some fast paths (e.g. in
mux_h2). Let's turn them to BUG_ON_HOT() instead.
Two new BUG_ON variants, BUG_ON_HOT() and CHECK_IF_HOT() are introduced
to debug hot paths (such as low-level API functions). These ones must
not be enabled by default as they would significantly affect performance
but they may be enabled by setting DEBUG_STRICT to a value above 1. In
this case, DEBUG_STRICT_ACTION is mostly respected with a small change,
which is that the no_crash variant of BUG_ON() isn't turned to a regular
warning but to a one-time warning so as not to spam with warnings in a
hot path. It is for this reason that there is no WARN_ON_HOT().
We used to have DEBUG_STRICT_NOCRASH to disable crashes on BUG_ON().
Now we have other levels (WARN_ON(), CHECK_IF()) so we need something
finer-grained.
This patch introduces DEBUG_STRICT_ACTION which takes an integer value.
0 disables crashes and is the equivalent of DEBUG_STRICT_NOCRASH. 1 is
the default and only enables crashes on BUG_ON(). 2 also enables crashes
on WARN_ON(), and 3 also enables warnings on CHECK_IF(), and is suited
to developers and CI.
Now we'll explicitly mention if the test was a bug/warn/check, and
"FATAL" is only displayed when the process crashes. The non-crashing
BUG_ON() also suggests to report to developers.
The only reason for warning once is to check if a condition really
happens. Let's use a term that better translates the intent, that's
important when reading the code.
Simplify the data manipulation of STREAM frames on TX. Only stream data
and len field are used to generate a valid STREAM frames from the
buffer. Do not use the offset field, which required that a single buffer
instance should be shared for every frames on a single stream.
This one will maintain a static counter per call place and will only
emit the warning on the first call. It may be used to invite users to
report an unexpected event without spamming them with messages.
This is the same as BUG_ON() except that it never crashes and only emits
a warning and a backtrace, inviting users to report the problem. This will
be usable for non-fatal issues that should not happen and need to be fixed.
This way the BUG_ON() when using DEBUG_STRICT_NOCRASH is effectively an
equivalent of WARN_ON().
The purpose is to make the program die at this point, so let's help the
compiler optimise the code (especially in sensitive areas) by telling it
that ABORT_NOW() does not return. This reduces the overall code size by
~0.5%.
The BUG_ON() macro handling is complicated because it relies on a
conditional CRASH_NOW() macro whose definition depends on DEBUG_STRICT
and DEBUG_STRICT_NOCRASH. Let's rethink the whole thing differently,
and instead make the underlying _BUG_ON() macro take a crash argument
to decide whether to crash or not, as well as a prefix and a suffix for
the message, that will allow to distinguish between variants. Now the
suffix is set to a message explaining we don't crash when needed.
This also allows to get rid of the CRASH_NOW() macro and to define
much simpler new macros.
The functions needed to manipulate the "tainted" flags were located in
too high a level to be callable from the lower code layers. Let's move
them to bug.h.
Since recent changes related to the conn-stream/stream-interface
refactoring, GCC reports potential null pointer dereferences when we get the
appctx, the stream or the stream-interface from the conn-strem. Of course,
depending on the time, these entities may be null. But at many places, we
know they are defined and it is safe to get them without any check. Thus, we
use ALREADY_CHECKED() macro to silent these warnings.
Note that the refactoring is unfinished, so it is not a real issue for now.
cs_detach_app() function is added to detach an app from a conn-stream. And
now, both cs_detach_app() and cs_detach_endp() release the conn-stream when
both the app and the endpoint are detached.
Thanks to all previous changes, it is now possible to move the
stream-interface into the conn-stream. To do so, some SI functions are
removed and their conn-stream counterparts are added. In addition, the
conn-stream is now responsible to create and release the
stream-interface. While the stream-interfaces were inlined in the stream
structure, there is now a pointer in the conn-stream. stream-interfaces are
now dynamically allocated. Thus a dedicated pool is added. It is a temporary
change because, at the end, the stream-interface structure will most
probably disappear.
Because cs_detach() is releated to the endpoint only, the function is
renamed. The main purpose of this patch is to be able to add a function to
detach the conn-stream from the application.
To be able to move the stream-interface from the stream to the conn-stream,
all access to the SI is done via the conn-stream. This patch is limited to
the stream part.
To be able to move the stream-interface from the stream to the conn-stream,
all access to the SI is done via the conn-stream. This patch is limited to
the stream-interface part.
frontend and backend conn-streams are now directly accesible from the
stream. This way, and with some other changes, it will be possible to remove
the stream-interfaces from the stream structure.
In the same way the conn-stream has a pointer to the stream endpoint , this
patch adds a pointer to the application entity in the conn-stream
structure. For now, it is a stream or a health-check. It is mandatory to
merge the stream-interface with the conn-stream.
Because appctx is now an endpoint of the conn-stream, there is no reason to
still have the stream-interface as appctx owner. Thus, the conn-stream is
now the appctx owner.
Thanks to previous changes, it is now possible to set an appctx as endpoint
for a conn-stream. This means the appctx is no longer linked to the
stream-interface but to the conn-stream. Thus, a pointer to the conn-stream
is explicitly stored in the stream-interface. The endpoint (connection or
appctx) can be retrieved via the conn-stream.
To be able to handle applets as a conn-stream endpoint, we must be prepared
to handle different types of endpoints. First of all, the conn-strream's
connection must no longer be used directly.
The backend conn-stream is no longer released on connection retry. This
means the conn-stream is detached from the underlying connection but not
released. Thus, during connection retries, the stream has always an
allocated conn-stream with no connection. All previous changes were made to
make this possible.
Note that .attach() mux callback function was changed to get the conn-stream
as argument. The muxes are no longer responsible to create the conn-stream
when a server connection is attached to a stream.
si_attach_conn() function should be used to attach a connection to a
stream-interface. It created a conn-stream if necessary. This function is
mandatory to be able to keep the backend conn-stream during connection
retries.
si_reset_endpoint() function may be used to reset the SI's endpoint without
releasing the conn-stream if the endpoint is a connection. If the endpoint
is an appctx, it is released. This change is mandatory to merge the SI and
the CS and keep the backend conn-stream attached to the stream during
connection retries.
cs_detach() function is added to detach a conn-stream from the underlying
connection. This part will evovle to handle applets too. Concretely,
cs_destroy() is split to detach the conn-stream from its endpoint, via
cs_detach(), and then, the conn-stream is released, via cs_free().
The conn-stream will progressively replace the stream-interface. Thus, a
stream will have to allocate the backend conn-stream during its
creation. This means it will be possible to have a conn-stream with no
connection. To prepare this change, we test the conn-stream's connection
when we retrieve it.
Stream-interfaces will be moved in the conn-stream and the appctx will be
moved at the same level than the muxes. Idea is to merge the
stream-interface and the conn-stream and have a better symmetry between the
muxes and the applets. To limit bugs during this refactoring, when the SI
endpoint is released, the appctx case is handled first.
New function pool_parse_debugging() is now dedicated to parsing options
of -dM. For now it only handles the optional memory poisonning byte, but
the function may already return an informative message to be printed for
help, a warning or an error. This way we'll reuse it for the settings
that will be needed for configurable debugging options.
The STG_REGISTER init level is used to register known keywords and
protocol stacks. It must be called earlier because some of the init
code already relies on it to be known. For example, "haproxy -vv"
for now is constrained to start very late only because of this.
This patch moves it between STG_LOCK and STG_ALLOC, which is fine as
it's used for static registration.
Now -dM will set POOL_DBG_POISON for consistency with the rest of the
pool debugging options. As such now we only check for the new flag,
which allows the default value to be preset.
