qc_dgrams_retransmit() prepares two list of frames to be retransmitted into
two datagrams. If the first datagram could not be sent, the TX buffer will
be purged with the prepared packet and its frames, but this was not the case for
the second list of frames.
Must be backported in 2.7.
This bug arrived with this commit which was not sufficient:
BUG/MEDIUM: quic: Missing TX buffer draining from qc_send_ppkts()
Indeed, there were also remaining allocated TX packets to be released and
their TX frames.
Implement qc_purge_tx_buf() to do so which depends on qc_free_tx_coalesced_pkts()
and qc_free_frm_list().
Must be backported to 2.7.
Released version 2.8-dev8 with the following main changes :
- BUG/MEDIUM: cli: Set SE_FL_EOI flag for '_getsocks' and 'quit' commands
- BUG/MEDIUM: cli: Eat output data when waiting for appctx shutdown
- BUG/MEDIUM: http-client: Eat output data when waiting for appctx shutdown
- BUG/MEDIUM: stats: Eat output data when waiting for appctx shutdown
- BUG/MEDIUM: log: Eat output data when waiting for appctx shutdown
- BUG/MEDIUM: dns: Kill idle DNS sessions during stopping stage
- BUG/MINOR: resolvers: Wakeup DNS idle task on stopping
- BUG/MEDIUM: resolvers: Force the connect timeout for DNS resolutions
- MINOR: hlua: Stop to check the SC state when executing a hlua cli command
- BUG/MEDIUM: mux-h1: Report EOI when a TCP connection is upgraded to H2
- BUG/MEDIUM: mux-h2: Never set SE_FL_EOS without SE_FL_EOI or SE_FL_ERROR
- MINOR: quic: Trace fix in quic_pto_pktns() (handshaske status)
- BUG/MINOR: quic: Wrong packet number space probing before confirmed handshake
- MINOR: quic: Modify qc_try_rm_hp() traces
- MINOR: quic: Dump more information at proto level when building packets
- MINOR: quic: Add a trace for packet with an ACK frame
- MINOR: activity: add a line reporting the average CPU usage to "show activity"
- BUG/MINOR: stick_table: alert when type len has incorrect characters
- MINOR: thread: keep a bitmask of enabled groups in thread_set
- MINOR: fd: optimize fd_claim_tgid() for use in fd_insert()
- MINOR: fd: add a lock bit with the tgid
- MINOR: fd: implement fd_migrate_on() to migrate on a non-local thread
- MINOR: receiver: reserve special values for "shards"
- MINOR: bind-conf: support a new shards value: "by-group"
- BUG/MEDIUM: fd: don't wait for tmask to stabilize if we're not in it.
- MINOR: quic: Add packet loss and maximum cc window to "show quic"
- BUG/MINOR: quic: Ignored less than 1ms RTTs
- MINOR: quic: Add connection flags to traces
- BUG/MEDIUM: quic: Code sanitization about acknowledgements requirements
- BUG/MINOR: quic: Possible wrapped values used as ACK tree purging limit.
- BUG/MINOR: quic: SIGFPE in quic_cubic_update()
- MINOR: quic: Display the packet number space flags in traces
- MINOR: quic: Remove a useless test about probing in qc_prep_pkts()
- BUG/MINOR: quic: Wrong Application encryption level selection when probing
- CI: bump "actions/checkout" to v3 for cross zoo matrix
- CI: enable monthly test on Fedora Rawhide
- BUG/MINOR: stream: Fix test on SE_FL_ERROR on the wrong entity
- BUG/MEDIUM: stream: Report write timeouts before testing the flags
- BUG/MEDIUM: stconn: Do nothing in sc_conn_recv() when the SC needs more room
- MINOR: stream: Uninline and export sess_set_term_flags() function
- MINOR: filters: Review and simplify errors handling
- REGTESTS: fix the race conditions in log_uri.vtc
- MINOR: channel: Forwad close to other side on abort
- MINOR: stream: Introduce stream_abort() to abort on both sides in same time
- MINOR: stconn: Rename SC_FL_SHUTR_NOW in SC_FL_ABRT_WANTED
- MINOR: channel/stconn: Replace channel_shutr_now() by sc_schedule_abort()
- MINOR: stconn: Rename SC_FL_SHUTW_NOW in SC_FL_SHUT_WANTED
- MINOR: channel/stconn: Replace channel_shutw_now() by sc_schedule_shutdown()
- MINOR: stconn: Rename SC_FL_SHUTR in SC_FL_ABRT_DONE
- MINOR: channel/stconn: Replace sc_shutr() by sc_abort()
- MINOR: stconn: Rename SC_FL_SHUTW in SC_FL_SHUT_DONE
- MINOR: channel/stconn: Replace sc_shutw() by sc_shutdown()
- MINOR: tree-wide: Replace several chn_cons() by the corresponding SC
- MINOR: tree-wide: Replace several chn_prod() by the corresponding SC
- BUG/MINOR: cli: Don't close when SE_FL_ERR_PENDING is set in cli analyzer
- MINOR: stconn: Stop to set SE_FL_ERROR on sending path
- MEDIUM: stconn: Forbid applets with more to deliver if EOI was reached
- MINOR: stconn: Don't clear SE_FL_ERROR when endpoint is reset
- MINOR: stconn: Add a flag to ack endpoint errors at SC level
- MINOR: backend: Set SC_FL_ERROR on connection error
- MINOR: stream: Set SC_FL_ERROR on channels' buffer allocation error
- MINOR: tree-wide: Test SC_FL_ERROR with SE_FL_ERROR from upper layer
- MEDIUM: tree-wide: Stop to set SE_FL_ERROR from upper layer
- MEDIUM: backend: Stop to use SE flags to detect connection errors
- MEDIUM: stream: Stop to use SE flags to detect read errors from analyzers
- MEDIUM: stream: Stop to use SE flags to detect endpoint errors
- MEDIUM: stconn: Rely on SC flags to handle errors instead of SE flags
- BUG/MINOR: stconn: Don't set SE_FL_ERROR at the end of sc_conn_send()
- BUG/MINOR: quic: Do not use ack delay during the handshakes
- CLEANUP: use "offsetof" where appropriate
- MINOR: ssl: remove OpenSSL 1.0.2 mention into certificate loading error
- BUG/MEDIUM: http-ana: Properly switch the request in tunnel mode on upgrade
- BUG/MEDIUM: log: Properly handle client aborts in syslog applet
- MINOR: stconn: Add a flag to report EOS at the stream-connector level
- MINOR: stconn: Propagate EOS from a mux to the attached stream-connector
- MINOR: stconn: Propagate EOS from an applet to the attached stream-connector
- MINOR: mux-h2: make the initial window size configurable per side
- MINOR: mux-h2: make the max number of concurrent streams configurable per side
- BUG/MINOR: task: allow to use tasklet_wakeup_after with tid -1
- CLEANUP: quic: remove unused QUIC_LOCK label
- CLEANUP: quic: remove unused scid_node
- CLEANUP: quic: remove unused qc param on stateless reset token
- CLEANUP: quic: rename quic_connection_id vars
- MINOR: quic: remove uneeded tasklet_wakeup after accept
- MINOR: quic: adjust Rx packet type parsing
- MINOR: quic: adjust quic CID derive API
- MINOR: quic: remove TID ref from quic_conn
- MEDIUM: quic: use a global CID trees list
- MINOR: quic: remove TID encoding in CID
- MEDIUM: quic: handle conn bootstrap/handshake on a random thread
- MINOR: quic: do not proceed to accept for closing conn
- MINOR: protocol: define new callback set_affinity
- MINOR: quic: delay post handshake frames after accept
- MEDIUM: quic: implement thread affinity rebinding
- BUG/MINOR: quic: transform qc_set_timer() as a reentrant function
- MINOR: quic: properly finalize thread rebinding
- MAJOR: quic: support thread balancing on accept
- MINOR: listener: remove unneeded local accept flag
- BUG/MINOR: http-ana: Update analyzers on both sides when switching in TUNNEL mode
- CLEANUP: backend: Remove useless debug message in assign_server()
- CLEANUP: cli: Remove useless debug message in cli_io_handler()
- BUG/MEDIUM: stconn: Propagate error on the SC on sending path
- MINOR: config: add "no-alpn" support for bind lines
- REGTESTS: add a new "ssl_alpn" test to test ALPN negotiation
- DOC: add missing documentation for "no-alpn" on bind lines
- MINOR: ssl: do not set ALPN callback with the empty string
- MINOR: ssl_crtlist: dump "no-alpn" on "show crtlist" when "no-alpn" was set
- MEDIUM: config: set useful ALPN defaults for HTTPS and QUIC
- BUG/MEDIUM: quic: prevent crash on Retry sending
- BUG/MINOR: cfgparse: make sure to include openssl-compat
- MINOR: clock: add now_mono_time_fast() function
- MINOR: clock: add now_cpu_time_fast() function
- MEDIUM: hlua: reliable timeout detection
- MEDIUM: hlua: introduce tune.lua.burst-timeout
- CLEANUP: hlua: avoid confusion between internal timers and tick based timers
- MINOR: hlua: hook yield on known lua state
- MINOR: hlua: safe coroutine.create()
- BUG/MINOR: quic: Stop removing ACK ranges when building packets
- MINOR: quic: Do not allocate too much ack ranges
- BUG/MINOR: quic: Unchecked buffer length when building the token
- BUG/MINOR: quic: Wrong Retry token generation timestamp computing
- BUG/MINOR: mux-quic: fix crash with app ops install failure
- BUG/MINOR: mux-quic: properly handle STREAM frame alloc failure
- BUG/MINOR: h3: fix crash on h3s alloc failure
- BUG/MINOR: quic: prevent crash on qc_new_conn() failure
- BUG/MINOR: quic: consume Rx datagram even on error
- CLEANUP: errors: fix obsolete function comments
- CLEANUP: server: fix update_status() function comment
- MINOR: server/event_hdl: add proxy_uuid to event_hdl_cb_data_server
- MINOR: hlua/event_hdl: rely on proxy_uuid instead of proxy_name for lookups
- MINOR: hlua/event_hdl: expose proxy_uuid variable in server events
- MINOR: hlua/event_hdl: fix return type for hlua_event_hdl_cb_data_push_args
- MINOR: server/event_hdl: prepare for upcoming refactors
- BUG/MINOR: event_hdl: don't waste 1 event subtype slot
- CLEANUP: event_hdl: updating obsolete comment for EVENT_HDL_CB_DATA
- CLEANUP: event_hdl: fix comment typo about _sync assertion
- MINOR: event_hdl: dynamically allocated event data members
- MINOR: event_hdl: provide event->when for advanced handlers
- MINOR: hlua/event_hdl: timestamp for events
- DOC: lua: restore 80 char limitation
- BUG/MINOR: server: incorrect report for tracking servers leaving drain
- MINOR: server: explicitly commit state change in srv_update_status()
- BUG/MINOR: server: don't miss proxy stats update on server state transitions
- BUG/MINOR: server: don't miss server stats update on server state transitions
- BUG/MINOR: server: don't use date when restoring last_change from state file
- MINOR: server: central update for server counters on state change
- MINOR: server: propagate server state change to lb through single function
- MINOR: server: propagate lb changes through srv_lb_propagate()
- MINOR: server: change adm_st_chg_cause storage type
- MINOR: server: srv_append_status refacto
- MINOR: server: change srv_op_st_chg_cause storage type
- CLEANUP: server: remove unused variables in srv_update_status()
- CLEANUP: server: fix srv_set_{running, stopping, stopped} function comment
- MINOR: server: pass adm and op cause to srv_update_status()
- MEDIUM: server: split srv_update_status() in two functions
- MINOR: server/event_hdl: prepare for server event data wrapper
- MINOR: quic: support migrating the listener as well
- MINOR: quic_sock: index li->per_thr[] on local thread id, not global one
- MINOR: listener: support another thread dispatch mode: "fair"
- MINOR: receiver: add a struct shard_info to store info about each shard
- MINOR: receiver: add RX_F_MUST_DUP to indicate that an rx must be duped
- MEDIUM: proto: duplicate receivers marked RX_F_MUST_DUP
- MINOR: proto: skip socket setup for duped FDs
- MEDIUM: config: permit to start a bind on multiple groups at once
- MINOR: listener: make accept_queue index atomic
- MEDIUM: listener: rework thread assignment to consider all groups
- MINOR: listener: use a common thr_idx from the reference listener
- MINOR: listener: resync with the thread index before heavy calculations
- MINOR: listener: make sure to avoid ABA updates in per-thread index
- MINOR: listener: always compare the local thread as well
- MINOR: Make `tasklet_free()` safe to be called with `NULL`
- CLEANUP: Stop checking the pointer before calling `tasklet_free()`
- CLEANUP: Stop checking the pointer before calling `pool_free()`
- CLEANUP: Stop checking the pointer before calling `task_free()`
- CLEANUP: Stop checking the pointer before calling `ring_free()`
- BUG/MINOR: cli: clarify error message about stats bind-process
- CI: cirrus-ci: bump FreeBSD image to 13-1
- REGTESTS: remove unsupported "stats bind-process" keyword
- CI: extend spellchecker whitelist, add "clen" as well
- CLEANUP: assorted typo fixes in the code and comments
- BUG/MINOR: sock_inet: use SO_REUSEPORT_LB where available
- BUG/MINOR: tools: check libssl and libcrypto separately
- BUG/MINOR: config: fix NUMA topology detection on FreeBSD
- BUILD: sock_inet: forward-declare struct receiver
- BUILD: proto_tcp: export the correct names for proto_tcpv[46]
- CLEANUP: protocol: move the l3_addrlen to plug a hole in proto_fam
- CLEANUP: protocol: move the nb_receivers to plug a hole in protocol
- REORG: listener: move the bind_conf's thread setup code to listener.c
- MINOR: proxy: make proxy_type_str() recognize peers sections
- MEDIUM: peers: call bind_complete_thread_setup() to finish the config
- MINOR: protocol: add a flags field to store info about protocols
- MINOR: protocol: move the global reuseport flag to the protocols
- MINOR: listener: automatically adjust shards based on support for SO_REUSEPORT
- MINOR: protocol: add a function to check if some features are supported
- MINOR: sock: add a function to check for SO_REUSEPORT support at runtime
- MINOR: protocol: perform a live check for SO_REUSEPORT support
- MINOR: listener: do not restrict CLI to first group anymore
- MINOR: listener: add a new global tune.listener.default-shards setting
- MEDIUM: listener: switch the default sharding to by-group
Sharding by-group is exactly identical to by-process for a single
group, and will use the same number of file descriptors for more than
one group, while significantly lowering the kernel's locking overhead.
Now that all special listeners (cli, peers) are properly handled, and
that support for SO_REUSEPORT is detected at runtime per protocol, there
should be no more reason for now switching to by-group by default.
That's what this patch does. It does only this and nothing else so that
it's easy to revert, should any issue be raised.
Testing on an AMD EPYC 74F3 featuring 24 cores and 48 threads distributed
into 8 core complexes of 3 cores each, shows that configuring 8 groups
(one per CCX) is sufficient to simply double the forwarded connection
rate from 112k to 214k/s, reducing kernel locking from 71 to 55%.
This new setting accepts "by-process", "by-group" and "by-thread" and
will dictate how listeners will be sharded by default when nothing is
specified. While the default remains "by-process", "by-group" should be
much more efficient with many threads, while not changing anything for
single-group setups.
Now that we're able to run listeners on any set of groups, we don't need
to maintain a special case about the stats socket anymore. It used to be
forced to group 1 only so as to avoid startup failures in case several
groups were configured, but if it's done now, it will automatically bind
the needed FDs to have one per group so this is no more an issue.
When testing if a protocol supports SO_REUSEPORT, we're now able to
verify if the OS does really support it. While it may be supported at
build time, it may possibly have been blocked in a container for
example so we'd rather know what it's like.
The new function _sock_supports_reuseport() will be used to check if a
protocol type supports SO_REUSEPORT or not. This will be useful to verify
that shards can really work.
The new function protocol_supports_flag() checks the protocol flags
to verify if some features are supported, but will support being
extended to refine the tests. Let's use it to check for REUSEPORT.
Now if multiple shards are explicitly requested, and the listener's
protocol doesn't support SO_REUSEPORT, sharding is disabled, which will
result in the socket being automatically duped if needed. A warning is
emitted when this happens. If "shards by-group" or "shards by-thread"
are used, these will automatically be turned down to 1 since we want
this to be possible easily using -dR on the command line without having
to djust the config. For "by-thread", a diag warning will be emitted to
help troubleshoot possible performance issues.
Some protocol support SO_REUSEPORT and others not. Some have such a
limitation in the kernel, and others in haproxy itself (e.g. sock_unix
cannot support multiple bindings since each one will unbind the previous
one). Also it's really protocol-dependent and not just family-dependent
because on Linux for some time it was supported for TCP and not UDP.
Let's move the definition to the protocols instead. Now it's preset in
tcp/udp/quic when SO_REUSEPORT is defined, and is otherwise left unset.
The enabled() config condition test validates IPv4 (generally sufficient),
and -dR / noreuseport all protocols at once.
We'll use these flags to know if some protocols are supported, and if
so, with what options/extensions. Reuseport will move there for example.
Two functions were added to globally set/clear a flag.
The listeners in peers sections were still not handing the thread
groups fine. Shards were silently ignored and if a listener was bound
to more than one group, it would simply fail. Now we can call the
dedicated function to resolve all this and possibly create the missing
extra listeners.
bind_complete_thread_setup() was adjusted to use the proxy_type_str()
instead of writing "proxy" at the only place where this word was still
hard-coded so that we continue to speak about peers sections when
relevant.
What used to be only two lines to apply a mask in a loop in
check_config_validity() grew into a 130-line block that performs deeply
listener-specific operations that do not have their place there anymore.
In addition it's worth noting that the peers code still doesn't support
shards nor being bound to more than one group, which is a second reason
for moving that code to its own function. Nothing was changed except
recreating the missing variables from the bind_conf itself (the fe only).
This field forces an unaligned hole between two list heads. Let's move
it up where it will be more easily combined with other fields. In
addition, turn it to unsigned while it's still not used.
There's a two-byte hole in proto_fam after sock_family, let's move the
l3_addrlen there as a ushort. Note that contrary to what the comment
says, it's still not used by hash algorithms though it could.
In 2.6-dev1, NUMA topology detection was enabled on FreeBSD with commit
f5d48f8b3 ("MEDIUM: cfgparse: numa detect topology on FreeBSD."). But
it suffers from a minor bug which is that it forgets to check for the
number of domains and always emits a confusing warning indicating that
multiple sockets were found while it's not the case.
This can be backported to 2.6.
The lib compatibility checks introduced in 2.8-dev6 with commit c3b297d5a
("MEDIUM: tools: further relax dlopen() checks too consider grouped
symbols") were partially incorrect in that they check at the same time
libcrypto and libssl. But if loading a library that only depends on
libcrypto, the ssl-only symbols will be missing and this might present
an inconsistency. This is what is observed on FreeBSD 13.1 when
libcrypto is being loaded, where it sees two symbols having disappeared.
The fix consists in splitting the checks for libcrypto and libssl.
No backport is needed, unless the patch above finally gets backported.
On FreeBSD 13.1 I noticed that thread balancing using shards was not
always working. Sometimes several threads would work, but most of the
time a single one was taking all the traffic. This is related to how
SO_REUSEPORT works on FreeBSD since version 12, as it seems there is
no guarantee that multiple sockets will receive the traffic. However
there is SO_REUSEPORT_LB that is designed exactly for this, so we'd
rather use it when available.
This patch may possibly be backported, but nobody complained and it's
not sure that many users rely on shards. So better wait for some feedback
before backporting this.
In 2.7-dev2, "stats bind-process" was removed by commit 94f763b5e
("MEDIUM: config: remove deprecated "bind-process" directives from
frontends") and an error message indicates that it's no more supported.
However it says "stats" is not supported instead of "stats bind-process",
making it a bit confusing.
This should be backported to 2.7.
By comparing the local thread's load with the least loaded thread's
load, we can further improve the fairness and at the same time also
improve locality since it allows a small ratio of connections not to
be migrated. This is visible on CPU usage with long connections on
very large thread counts (224) and high bandwidth (200G). The cost
of checking the local thread's load remains fairly low so there's no
reason not to do this. We continue to update the index if we select
the local thread, because it means that the two other threads were
both more loaded so we'd rather find better ones.
One limitation of the current thread index mechanism is that if the
values are assigned multiple times to the same thread and the index
loops, it can match again the old value, which will not prevent a
competing thread from finishing its CAS and assigning traffic to a
thread that's not the optimal one. The probability is low but the
solution is simple enough and consists in implementing an update
counter in the high bits of the index to force a mismatch in this
case (assuming we don't try to cover for extremely unlikely cases
where the update counter loops while the index remains equal). So
let's do that. In order to improve the situation a little bit, we
now set the index to a ulong so that in 32 bits we have 8 bits of
counter and in 64 bits we have 40 bits.
During heavy accept competition, the CAS will occasionally fail and
we'll have to go through all the calculation again. While the first
two loops look heavy, they're almost never taken so they're quite
cheap. However the rest of the operation is heavy because we have to
consult connection counts and queue indexes for other threads, so
better double-check if the index is still valid before continuing.
Tests show that it's more efficient do retry half-way like this.
Instead of seeing each listener use its own thr_idx, let's use the same
for all those from a shard. It should provide more accurate and smoother
thread allocation.
Till now threads were assigned in listener_accept() to other threads of
the same group only, using a single group mask. Now that we have all the
relevant info (array of listeners of the same shard), we can spread the
thr_idx to cover all assigned groups. The thread indexes now contain the
group number in their upper bits, and the indexes run over te whole list
of threads, all groups included.
One particular subtlety here is that switching to a thread from another
group also means switching the group, hence the listener. As such, when
changing the group we need to update the connection's owner to point to
the listener of the same shard that is bound to the target group.
There has always been a race when checking the length of an accept queue
to determine which one is more loaded that another, because the head and
tail are read at two different moments. This is not required, we can merge
them as two 16 bit numbers inside a single 32-bit index that is always
accessed atomically. This way we read both values at once and always have
a consistent measurement.
Now it's possible for a bind line to span multiple thread groups. When
this happens, the first one will become the reference and will be entirely
set up, and the subsequent ones will be duplicated from this reference,
so that they can be registered in distinct groups. The reference is
always setup and started first so it is always available when the other
ones are started.
The doc was updated to reflect this new possibility with its limitations
and impacts, and the differences with the "shards" option.
It's not strictly necessary, but it's still better to avoid setting
up the same socket multiple times when it's being duplicated to a few
FDs. We don't change that for inherited ones however since they may
really need to be set up, so we only skip duplicated ones.
The different protocol's ->bind() function will now check the receiver's
RX_F_MUST_DUP flag to decide whether to bind a fresh new listener from
scratch or reuse an existing one and just duplicate it. It turns out
that the existing code already supports reusing FDs since that was done
as part of the FD passing and inheriting mechanism. Here it's not much
different, we pass the FD of the reference receiver, it gets duplicated
and becomes the new receiver's FD.
These FDs are also marked RX_F_INHERITED so that they are not exported
and avoid being touched directly (only the reference should be touched).
The purpose of this new flag will be to mark that some listeners
duplicate their reference's FD instead of trying to setup a completely
new listener from scratch. This will be used when multiple groups want
to listen to the same socket, via multiple FDs.
In order to create multiple receivers for one multi-group shard, we'll
need some more info about the shard. Here we store:
- the number of groups (= number of receivers)
- the number of threads (will be used for accept LB)
- pointer to the reference rx (to get the FD and to find all threads)
- pointers to the other members (to iterate over all threads)
For now since there's only one group per shard it remains simple. The
listener deletion code already takes care of removing the current
member from its shards list and moving others' reference to the last
one if it was their reference (so as to avoid o(n^2) updates during
ordered deletes).
Since the vast majority of setups will not use multi-group shards, we
try to save memory usage by only allocating the shard_info when it is
needed, so the principle here is that a receiver shard_info==NULL is
alone and doesn't share its socket with another group.
Various approaches were considered and tests show that the management
of the listeners during boot makes it easier to just attach to or
detach from a shard_info and automatically allocate it if it does not
exist, which is what is being done here.
For now the attach code is not called, but detach is already called
on delete.
This new algorithm for rebalancing incoming connections to multiple
threads is simpler and instead of considering the threads load, it will
only cycle through all of them, offering a fair share of the traffic to
each thread. It may be well suited for short-lived connections but is
also convenient for very large thread counts where it's not always certain
that the least loaded thread will always be found.
There's a li_per_thread array in each listener for use with QUIC
listeners. Since thread groups were introduced, this array can be
allocated too large because global.nbthread is allocated for each
listener, while only no more than MIN(nbthread,MAX_THREADS_PER_GROUP)
may be used by a single listener. This was because the global thread
ID is used as the index instead of the local ID (since a listener may
only be used by a single group). Let's just switch to local ID and
reduce the allocated size.
When migrating a quic_conn to another thread, we may need to also
switch the listener if the thread belongs to another group. When
this happens, the freshly created connection will already have the
target listener, so let's just pick it from the connection and use
it in qc_set_tid_affinity(). Note that it will be the caller's
responsibility to guarantee this.
Adding the possibility to publish an event using a struct wrapper
around existing SERVER events to provide additional contextual info.
Using the specific struct wrapper is not required: it is supported
to cast event data as a regular server event data struct so
that we don't break the existing API.
However, casting event data with a more explicit data type allows
to fetch event-only relevant hints.
Considering that srv_update_status() is now synchronous again since
3ff577e1 ("MAJOR: server: make server state changes synchronous again"),
and that we can easily identify if the update is from an operational
or administrative context thanks to "MINOR: server: pass adm and op cause
to srv_update_status()".
And given that administrative and operational updates cannot be cumulated
(since srv_update_status() is called synchronously and independently for
admin updates and state/operational updates, and the function directly
consumes the changes).
We split srv_update_status() in 2 distinct parts:
Either <type> is 0, meaning the update is an operational update which
is handled by directly looking at cur_state and next_state to apply the
proper transition.
Also, the check to prevent operational state from being applied
if MAINT admin flag is set is no longer needed given that the calling
functions already ensure this (ie: srv_set_{running,stopping,stopped)
Or <type> is 1, meaning the update is an administrative update, where
cur_admin and next_admin are evaluated to apply the proper transition and
deduct the resulting server state (next_state is updated implicitly).
Once this is done, both operations share a common code path in
srv_update_status() to update proxy and servers stats if required.
Thanks to this change, the function's behavior is much more predictable,
it is not an all-in-one function anymore. Either we apply an operational
change, else it is an administrative change. That's it, we cannot mix
the 2 since both code paths are now properly separated.
Operational and administrative state change causes are not propagated
through srv_update_status(), instead they are directly consumed within
the function to provide additional info during the call when required.
Thus, there is no valid reason for keeping adm and op causes within
server struct. We are wasting space and keeping uneeded complexity.
We now exlicitly pass change type (operational or administrative) and
associated cause to srv_update_status() so that no extra storage is
needed since those values are only relevant from srv_update_status().
