Commit 8fbc12f3 authored by Fabiano Rosas's avatar Fabiano Rosas Committed by Stefan Hajnoczi
Browse files

tracetool: Include thread id information in log backend 



Currently the log backend prints the process id of QEMU at the start
of each output line, but since threads share the same PID there is no
clear distinction between their outputs.

Having the thread id present in the log makes it easier to see when
output comes from different threads. E.g.:

12423@1538597569.672527:qemu_mutex_lock waiting on mutex 0x1103ee60 (/root/qemu/util/main-loop.c:236)
...
12430@1538597569.503928:qemu_mutex_unlock released mutex 0x1103ee60 (/root/qemu/cpus.c:1238)
12431@1538597569.503937:qemu_mutex_locked taken mutex 0x1103ee60 (/root/qemu/cpus.c:1257)
^here

In the above, 12423 is the main process id and 12430 & 12431 are the
two vcpu threads.

 (qemu) info cpus
 * CPU #0: thread_id=12430
   CPU #1: thread_id=12431

Suggested-by: default avatarMurilo Opsfelder Araujo <muriloo@linux.ibm.com>
Signed-off-by: default avatarFabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
parent bb9bf94b

scripts/tracetool/backend/log.py

+1 −1
Original line number Diff line number Diff line
@@ -39,7 +39,7 @@ def generate_h(event, group): 
        '        struct timeval _now;',

        '        gettimeofday(&_now, NULL);',

        '        qemu_log("%%d@%%zu.%%06zu:%(name)s " %(fmt)s "\\n",',

        '                 getpid(),',

        '                 qemu_get_thread_id(),',

        '                 (size_t)_now.tv_sec, (size_t)_now.tv_usec',

        '                 %(argnames)s);',

        '    }',