qemu/trace
Daniel P. Berrange 8ed5372874 trace: don't abort qemu if ftrace can't be initialized
If the ftrace backend is compiled into QEMU, any attempt
to start QEMU while non-root will fail due to the
inability to open /sys/kernel/debug/tracing/tracing_on.

Add a fallback into the code so that it connects up the
trace_marker_fd variable to /dev/null when getting
EACCES on the 'trace_on' file. This allows QEMU to
run, with ftrace turned into a no-op.

[Fixed s/setting/getting/ and s/EACCESS/EACCES/ errors pointed out by
Eric Blake <eblake@redhat.com>.
--Stefan]

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475588159-30598-13-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-10-12 09:35:54 +02:00
..
control-internal.h trace: remove the TraceEventID and TraceEventVCPUID enums 2016-10-12 09:35:54 +02:00
control-target.c trace: remove the TraceEventID and TraceEventVCPUID enums 2016-10-12 09:35:54 +02:00
control.c trace: remove the TraceEventID and TraceEventVCPUID enums 2016-10-12 09:35:54 +02:00
control.h trace: remove the TraceEventID and TraceEventVCPUID enums 2016-10-12 09:35:54 +02:00
event-internal.h trace: remove the TraceEventID and TraceEventVCPUID enums 2016-10-12 09:35:54 +02:00
ftrace.c trace: don't abort qemu if ftrace can't be initialized 2016-10-12 09:35:54 +02:00
ftrace.h Clean up decorations and whitespace around header guards 2016-07-12 16:20:46 +02:00
Makefile.objs rules.mak: quiet-command: Split command name and args to print 2016-10-06 12:11:51 +01:00
mem-internal.h Clean up decorations and whitespace around header guards 2016-07-12 16:20:46 +02:00
mem.h Clean up decorations and whitespace around header guards 2016-07-12 16:20:46 +02:00
qmp.c trace: convert code to use event iterators 2016-10-12 09:35:54 +02:00
simple.c trace: emit name <-> ID mapping in simpletrace header 2016-10-12 09:35:54 +02:00
simple.h trace: remove the TraceEventID and TraceEventVCPUID enums 2016-10-12 09:35:54 +02:00