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2018-07-19tracing: Use double-dash spelling for trace optionYaowei Bai
The '-trace' and '--trace' spellings are only both supported in qemu binary, while for qemu-nbd or qemu-img only '--trace' spelling is supported. So for the consistency of trace option invocation, we should use double-dash spelling in our documentation. This's also mentioned in https://wiki.qemu.org/BiteSizedTasks#Consistent_option_usage_in_documentation . Signed-off-by: Yaowei Bai <baiyaowei@cmss.chinamobile.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1530674247-31200-1-git-send-email-baiyaowei@cmss.chinamobile.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-06-27trace: forbid floating point typesStefan Hajnoczi
Only one existing trace event uses a floating point type. Unfortunately float and double cannot be supported since SystemTap does not have floating point types. Remove float and double from the whitelist and document this limitation. Update the migrate_transferred trace event to use uint64_t instead of double. Cc: Dr. David Alan Gilbert <dgilbert@redhat.com> Cc: Daniel P. Berrangé <berrange@redhat.com> Cc: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Reviewed-by: Juan Quintela <quintela@redhat.com> Message-id: 20180621150254.4922-1-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-08-01trace: add trace_event_get_state_backends()Stefan Hajnoczi
Code that checks dstate is unaware of SystemTap and LTTng UST dstate, so the following trace event will not fire when solely enabled by SystemTap or LTTng UST: if (trace_event_get_state(TRACE_MY_EVENT)) { str = g_strdup_printf("Expensive string to generate ...", ...); trace_my_event(str); g_free(str); } Add trace_event_get_state_backends() to fetch backend dstate. Those backends that use QEMU dstate fetch it as part of generate_h_backend_dstate(). Update existing trace_event_get_state() callers to use trace_event_get_state_backends() instead. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20170731140718.22010-3-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-07-17trace: update old trace events in docsStefan Hajnoczi
Commit c5f1ad429cdf26023cf331075a7d327708e3db6d ("block: Remove bdrv_aio_readv/writev/flush()") removed bdrv_aio_readv()/bdrv_aio_writev() so the example in the tracing documentation is no longer valid. Reported-by: Wang Dong <dongdwdw@linux.vnet.ibm.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 20170714133111.27359-1-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-07docs: create config/, devel/ and spin/ subdirectoriesPaolo Bonzini
Developer documentation should be its own manual. As a start, move all developer-oriented files to a separate directory. Also move non-text files to their own directories: docs/config/ for QEMU -readconfig input, and docs/spin/ for formal models to be used with the SPIN model checker. Reviewed-by: Daniel P. Berrange <berrange@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>