Currently both virtlogd and virtlockd use a single worker thread for
dispatching RPC messages. Even this is overkill and their RPC message
handling callbacks all run in short, finite time and so blocking the
main loop is not an issue like you'd see in libvirtd with long running
QEMU commands.
By setting max_workers==0, we can turn off the worker thread and run
these daemons single threaded. This in turn fixes a serious problem in
the virtlockd daemon whereby it loses all fcntl() locks at re-exec due
to multiple threads existing. fcntl() locks only get preserved if the
process is single threaded at time of exec().
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Jim Fehlig <jfehlig@suse.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Add a virtlogd-admin-sock can serves the admin protocol for the virtlogd
daemon and define a virtlogd:///{system,session} URI scheme for
connecting to it.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
With the current code it is neccessary to call
virNetDaemonNewPostExecRestart()
and then for each server that needs restarting you are supposed
to call
virNetDaemonAddSeverPostExecRestart()
This is fine if there's only ever one server, but as soon as you
have two servers it is impossible to use this design. The code
has no idea which servers were recorded in the JSON state doc,
nor in which order the hash table serialized its keys.
So this patch changes things so that we only call
virNetDaemonNewPostExecRestart()
passing in a callback, which is invoked once for each server
found int he JSON state doc.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
We put the server into a hash table as we do with the other daemons,
there is no compelling reason why it should have another pointer
dedicated just to the server. Besides, the locking daemon doesn't have
it and virtlogd is essentially a copy paste of virtlockd.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Commit 94c465d0 refactored the logging setup phase but introduced an
issue, where the daemon ignores verbose mode when there are no outputs
defined and the default must be used. The problem is that the default
output was determined too early, thus ignoring the potential '--verbose'
option taking effect. This patch postpones the creation of the default
output to the very last moment when nothing else can change. Since the
default output is only created during the init phase, it's safe to leave
the pointer as NULL for a while, but it will be set eventually, thus not
affecting runtime.
Patch also adjusts both the other daemons.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1442947
Signed-off-by: Erik Skultety <eskultet@redhat.com>
The log and lock protocol don't have an extra handshake to close the
connection. Instead they just close the socket. Unfortunately that
resulted into a lot of spurious garbage logged to the system log files:
2017-03-17 14:00:09.730+0000: 4714: error : virNetSocketReadWire:1800 : End of file while reading data: Input/output error
or in the journal as:
Mar 13 16:19:33 xxxx virtlogd[32360]: End of file while reading data: Input/output error
Use the new facility in the netserverclient to suppress the IO error
report from the virNetSocket layer.
Now that virLog{Get,Set}DefaultOutput routines are introduced we can wire them
up to the daemon's logging initialization code. Also, change the order of
operations a bit so that we still strictly honor our precedence of settings:
cmdline > env > config now that outputs and filters are not appended anymore.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Along with an empty string, it should also be possible for users to pass
NULL to the public APIs which in turn would trigger a routine(future
work) responsible for defining an appropriate default logging output
given the current circumstances.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Similar to outputs, parser should do parsing only, thus the 'define' logic
is going to be stripped from virLogParseAndDefineFilters by replacing calls to
this method to virLogSetFilters instead.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Since virLogParseAndDefineOutputs is going to be stripped from 'output defining'
logic, replace all relevant occurrences with virLogSetOutputs call to make the
change transparent to all original callers (daemons mostly).
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Right now virLogParse* functions are doing both parsing and defining of filters
and outputs which should be two separate operations. Since the naming is
apparently a bit poor this patch renames these functions to
virLogParseAndDefine* which eventually will be replaced by virLogSet*.
Additionally, virLogParse{Filter,Output} will be later (after the split) reused,
so that these functions do exactly what the their name suggests.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Currently virtlogd has a hardcoded max file size of 128kb
and max of 3 backups. This adds two new config parameters
to /etc/libvirt/virtlogd.conf to let these be customized.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Admin API needs a way of addressing specific clients. Unlike servers, which we
are happy to address by names both because its name reflects its purpose (to
some extent) and we only have two of them (so far), naming clients doesn't make
any sense, since a) each client is an anonymous, i.e. not recognized after a
disconnect followed by a reconnect, b) we can't predict what kind of requests
it's going to send to daemon, and c) the are loads of them comming and going,
so the only viable option is to use an ID which is of a reasonably wide data
type.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Since servers know their name, there is no need to supply such
information twice. Also defeats inconsistencies.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
At first I did not want to do this, but after trying to implement some
newer feaures in the admin API I realized we need that to make our lives
easier. On the other hand they are not saved redundantly and the
virNetServer objects are still kept in a hash table.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Since the daemon can manage and add (at fresh start) multiple servers,
we also should be able to add them from a JSON state file in case of a
daemon restart, so post exec restart support for multiple servers is also
provided. Patch also updates virnetdaemontest accordingly.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
With some versions of GLibC / GCC, a variable called 'daemon'
will result in a warning about clashing with the function also
named 'daemon'. Rename it to 'dmn' to avoid the clash.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The virtlogd daemon is launched with a 30 second timeout for
unprivileged users. Unfortunately the timeout is only inhibited
while RPC clients are connected, and they only connect for a
short while to open the log file descriptor. We need to hold
an inhibition for as long as the log file descriptor itself
is open.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Define a new RPC protocol for the virtlogd daemon that provides
for handling of logs. The initial RPC method defined allows a
client to obtain a file handle to use for writing to a log
file for a guest domain. The file handle passed back will not
actually refer to the log file, but rather an anonymous pipe.
The virtlogd daemon will forward I/O between them, ensuring
file rotation happens when required.
Initially the log setup is hardcoded to cap log files at
128 KB, and keep 3 backups when rolling over, which gives
a max usage of 512 KB per guest.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Copy the virtlockd codebase across to form the initial virlogd
code. Simple search & replace of s/lock/log/ and gut the remote
protocol & dispatcher. This gives us a daemon that starts up
and listens for connections, but does nothing with them.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
