The CLI proxy was not handling payload. To do that, we needed to keep a
connection active on a server and to transfer each new line over that
connection until we receive a empty line.
The CLI proxy handles the payload in the same way that the CLI do it.
Examples:
$ echo -e "@1;add map #-1 <<\n$(cat data)\n" | socat /tmp/master-socket -
$ socat /tmp/master-socket readline
prompt
master> @1
25130> add map #-1 <<
+ test test
+ test2 test2
+ test3 test3
+
25130>
During a payload transfer, we need to wait for the data even when we are
not in interactive mode. Indeed, the data could be received line per
line progressively instead of in one recv.
Previously the CLI was doing a SHUTW just after the first line if it was
not in interactive mode. We now check if we are in payload mode to do
a SHUTW.
Should be backported in 1.8.
Rework the CLI proxy parser to look more like the CLI parser, corner
case and escaping are handled the same way.
The parser now splits the commands in words instead of just handling
the prefixes.
It's easier to compare words and arguments of a command this way and to
parse internal command that will be consumed directly by the CLI proxy.
These potential null-deref warnings are emitted on gcc 7 and above
when threads are disabled due to the use of objt_server() after an
existing validity test. Let's switch to __objt_server() since we
know the pointer is valid, it will not confuse the compiler.
Some of these may be backported to 1.8.
This switches explicit calls to various trivial registration methods for
keywords, muxes or protocols from constructors to INITCALL1 at stage
STG_REGISTER. All these calls have in common to consume a single pointer
and return void. Doing this removes 26 constructors. The following calls
were addressed :
- acl_register_keywords
- bind_register_keywords
- cfg_register_keywords
- cli_register_kw
- flt_register_keywords
- http_req_keywords_register
- http_res_keywords_register
- protocol_register
- register_mux_proto
- sample_register_convs
- sample_register_fetches
- srv_register_keywords
- tcp_req_conn_keywords_register
- tcp_req_cont_keywords_register
- tcp_req_sess_keywords_register
- tcp_res_cont_keywords_register
- flt_register_keywords
Fix some memory leak and a FD leak in the error path of the master proxy
initialisation. It's a really minor issue since the process is exiting
when taking those error paths.
Valgrind's memcheck reports memory leaks in cli.c, because
the out parameter of memprintf is not properly freed:
==31035== 11 bytes in 1 blocks are definitely lost in loss record 16 of 101
==31035== at 0x4C2DB8F: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==31035== by 0x4C2FDEF: realloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==31035== by 0x4A3C72: my_realloc2 (standard.h:1364)
==31035== by 0x4A3C72: memvprintf (standard.c:3459)
==31035== by 0x4A3D93: memprintf (standard.c:3482)
==31035== by 0x4AF77E: mworker_cli_sockpair_new (cli.c:2324)
==31035== by 0x48E826: init (haproxy.c:1749)
==31035== by 0x408BBC: main (haproxy.c:2725)
==31035==
==31035== 11 bytes in 1 blocks are definitely lost in loss record 17 of 101
==31035== at 0x4C2DB8F: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==31035== by 0x4C2FDEF: realloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==31035== by 0x4A3C72: my_realloc2 (standard.h:1364)
==31035== by 0x4A3C72: memvprintf (standard.c:3459)
==31035== by 0x4A3D93: memprintf (standard.c:3482)
==31035== by 0x4AF071: mworker_cli_proxy_create (cli.c:2172)
==31035== by 0x48EC89: init (haproxy.c:1760)
==31035== by 0x408BBC: main (haproxy.c:2725)
These leaks were introduced in commits
ce83b4a5dd and
8a02257d88
which are specific to haproxy 1.9 dev.
The "cpust_{tot,1s,15s}" fields used to report milliseconds but nothing
in the value's title made this explicit. Let's rename the field to report
"cpust_ms_{tot,1s,15s}" to more easily remind that the unit represents
milliseconds.
Since we know the time it takes to process everything between two poll()
calls, we can use this as the max latency measurement any task will
experience and average it.
This code does this, and reports in "show activity" the average of this
loop time over the last 1024 poll() loops, for each thread. It will vary
quickly at high loads and slowly under low to moderate loads, depending
on the rate at which poll() is called. The latency a task experiences
is expected to be half of this on average.
At the moment the situation with activity measurement is quite tricky
because the struct activity is defined in global.h and declared in
haproxy.c, with operations made in time.h and relying on freq_ctr
which are defined in freq_ctr.h which itself includes time.h. It's
barely possible to touch any of these files without breaking all the
circular dependency.
Let's move all this stuff to activity.{c,h} and be done with it. The
measurement of active and stolen time is now done in a dedicated
function called just after tv_before_poll() instead of mixing the two,
which used to be a lazy (but convenient) decision.
No code was changed, stuff was just moved around.
In the output of 'show fd', the worker CLI's socketpair was still
handled by an "unknown" function. That can be really confusing during
debug. Fixed it by showing "mworker_accept_wrapper" instead.
Remaining calls to si_cant_put() were all for lack of room and were
turned to si_rx_room_blk(). A few places where SI_FL_RXBLK_ROOM was
cleared by hand were converted to si_rx_room_rdy().
The now unused si_cant_put() function was removed.
A number of calls to si_cant_put() were used in fact to request being
called back once a buffer is available. These ones are not needed anymore
since si_alloc_ibuf() already sets the SI_FL_RXBLK_BUFF flag when called
in appctx context. Those called with a foreign stream-int are simply turned
to si_rx_buff_blk().
In master-worker mode, the socketpair CLI listener of the worker is now
marked unstoppable, which allows to connect to the CLI of an old process
which is in a leaving state, allowing to debug it.
It doesn't make sense to limit this code to applets, as any stream
interface can use it. Let's rename it by simply dropping the "applet_"
part of the name. No other change was made except updating the comments.
A bug occurs when the CLI proxy of the master received a command which
is prefixed by some spaces but without a routing prefix (@).
In this case the pcli_parse_request() was returning a wrong number of
data to forward.
The response analyzer was called twice and the prompt displayed twice.
This patch implements analysers for parsing the CLI and extra features
for the master's CLI.
For each command (sent alone, or separated by ; or \n) the request
analyser will determine to which server it should send the request.
The 'mode cli' proxy is able to parse a prefix for each command which is
used to select the apropriate server. The prefix start by @ and is
followed by "master", the PID preceded by ! or the relative PID. (e.g.
@master, @1, @!1234). The servers are not round-robined anymore.
The command is sent with a SHUTW which force the server to close the
connection after sending its response. However the proxy allows a
keepalive connection on the client side and does not close.
The response analyser does not do much stuff, it only reinits the
connection when it received a close from the server, and forward the
response. It does not analyze the response data.
The only guarantee of the end of the response is the close of the
server, we can't rely on the double \n since it's not send by every
command.
This could be reimplemented later as a filter.
Add a struct server pointer in the mworker_proc struct so we can easily
use it as a target for the mworker proxy.
pcli_prefix_to_pid() is used to find the right PID of the worker
when using a prefix in the CLI. (@master, @#<relative pid> , @<pid>)
pcli_pid_to_server() is used to find the right target server for the
CLI proxy.
The master process does not need all the keywords of the cli, add 2
flags to chose which keyword to use.
It might be useful to activate some of them in a debug mode later...
This patch introduces mworker_cli_proxy_new_listener() which allows the
creation of new listeners for the CLI proxy.
Using this function it is possible to create new listeners from the
program arguments with -Sa <unix_socket>. It is allowed to create
multiple listeners with several -Sa.
This patch implements a listen proxy within the master. It uses the
sockpair of all the workers as servers.
In the current state of the code, the proxy is only doing round robin on
the CLI of the workers. A CLI mode will be needed to know to which CLI
send the requests.
The init code of the mworker_proc structs has been moved before the
init of the listeners.
Each socketpair is now connected to a CLI within the workers, which
allows the master to access their CLI.
The inherited flag of the worker side socketpair is removed so the
socket can be closed in the master.
The purpose is to detect if threads or processes are competing for the
same CPU. This can happen when threads are incorrectly bound, or after a
reload if the previous process still has an important activity. With
threads this situation is problematic because a preempted thread holding
a lock will block other ones waiting for this lock to be released.
A first attempt consisted in measuring the cumulated lost time more
precisely but the system's scheduler is smart enough to try to limit the
thread preemption rate by mostly context switching during poll()'s blank
periods, so most of the time lost is not seen. In essence this is good
because it means a thread is not preempted with a lock held, and even
regarding the rendez-vous point it cannot prevent the other ones from
making progress. But still it happens tens to hundreds of times per
second that a thread might be preempted, so it's still possible to detect
that the situation is happening, thus it's interesting to measure and
report its frequency.
Each time we enter the poller, we check the CPU time spent working and
see if we've lost time doing something else. To limit false positives,
we're only interested in losses of 500 microseconds or more (i.e. half
a clock tick on a 1 kHz system). If so, it indicates that some time was
stolen by another thread or process. Note that we purposely store some
sub-millisecond counters so that under heavy traffic with a 1 kHz clock,
it's still possible to measure something without being subject to the
risk of rounding errors (i.e. if exactly 1 ms is stolen it's possible
that the time difference could often be slightly lower).
This counter of lost CPU time slots time is reported in "show activity"
in numbers of milliseconds of CPU lost per second, per 15s, and total
over the process' life. By definition, the per-second counter cannot
report values larger than 1000 per thread per second and the 15s one
will be limited to 15000/s in the worst case, but it's possible that
peak values exceed such thresholds after long pauses.
Theorically nothing would prevent a front applet form connecting to a stats
socket, and if a "getsock" command was issued, it would cause a crash. Right
now nothing in the code does this so in its current form there is no impact.
It may or may not be backported to 1.8.
The "show fd" command was implemented as a debugging aid but it's not
thread safe. Its features have grown, it can now dump some mux-specific
parts and is being used in production to capture some useful debugging
traces. But it will quickly crash the process when used during an H2 load
test for example, especially when haproxy is built with the DEBUG_UAF
option. It cannot afford not to be thread safe anymore. Let's make use
of the new rendez-vous point using thread_isolate() / thread_release()
to ensure that the data being dumped are not changing under us. The dump
becomes slightly slower under load but now it's safe.
This should be backported to 1.8 along with the rendez-vous point code
once considered stable enough.
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.
It remained some fragments of the old buffers API in debug messages, here and
there.
This was caused by the recent buffer API changes, no backport is needed.
Now all the code used to manipulate chunks uses a struct buffer instead.
The functions are still called "chunk*", and some of them will progressively
move to the generic buffer handling code as they are cleaned up.
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.