{error,warn}_report_once() are a special case of the new functions
and can simply switch to them.
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20180830145902.27376-3-cohuck@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Dispense with unlikely() to keep the macros as simple as possible]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Add two functions to print an error/warning report once depending
on a passed-in condition variable and flip it if printed. This is
useful if you want to print a message not once-globally, but e.g.
once-per-device.
Inspired by warn_once() in hw/vfio/ccw.c, which has been replaced
with warn_report_once_cond().
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20180830145902.27376-2-cohuck@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Function comments reworded]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
There are many error_report()s that can be used in frequently called
functions, especially on IO paths. That can be unideal in that
malicious guest can try to trigger the error tons of time which might
use up the log space on the host (e.g., libvirt can capture the stderr
of QEMU and put it persistently onto disk). In VT-d emulation code, we
have trace_vtd_error() tracer. AFAIU all those places can be replaced
by something like error_report() but trace points are mostly used to
avoid the DDOS attack that mentioned above. However using trace points
mean that errors are not dumped if trace not enabled.
It's not a big deal in most modern server managements since we have
things like logrotate to maintain the logs and make sure the quota is
expected. However it'll still be nice that we just provide another way
to restrict message generations. In most cases, this kind of
error_report()s will only provide valid information on the first message
sent, and all the rest of similar messages will be mostly talking about
the same thing. This patch introduces *_report_once() helpers to allow
a message to be dumped only once during one QEMU process's life cycle.
It will make sure: (1) it's on by deffault, so we can even get something
without turning the trace on and reproducing, and (2) it won't be
affected by DDOS attack.
To implement it, I stole the printk_once() macro from Linux.
CC: Eric Blake <eblake@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180815095328.32414-2-peterx@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Whitespace adjusted, comments improved]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Add warn_report(), warn_vreport() for reporting warnings, and
info_report(), info_vreport() for informational messages.
These are implemented them with a helper function factored out of
error_vreport(), suitably generalized. This patch makes no changes
to the output of the original error_report() function.
Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <c89e9980019f296ec9aa38d7689ac4d5c369296d.1499866456.git.alistair.francis@xilinx.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Leave the implementation of error_vprintf and error_vprintf_unless_qmp
(the latter now trivially wrapped by error_printf_unless_qmp) to
libqemustub.a and monitor.c. This has two advantages: it lets us
remove the monitor_printf and monitor_vprintf stubs, and it lets
tests provide a different implementation of the functions that uses
g_test_message.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1477326663-67817-2-git-send-email-pbonzini@redhat.com>
Header guard symbols should match their file name to make guard
collisions less likely. Offenders found with
scripts/clean-header-guards.pl -vn.
Cleaned up with scripts/clean-header-guards.pl, followed by some
renaming of new guard symbols picked by the script to better ones.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.
This commit was created with scripts/clean-includes.
NB: If this commit breaks compilation for your out-of-tree
patchseries or fork, then you need to make sure you add
#include "qemu/osdep.h" to any new .c files that you have.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Issue]
When we offer a customer support service and a problem happens
in a customer's system, we try to understand the problem by
comparing what the customer reports with message logs of the
customer's system.
In this case, we often need to know when the problem happens.
But, currently, there is no timestamp in qemu's error messages.
Therefore, we may not be able to understand the problem based on
error messages.
[Solution]
Add a timestamp to qemu's error message logged by
error_report() with g_time_val_to_iso8601().
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
