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And it's not hard to figure out that the former two are built upon the third one, and the reason why we see this inconsistency is that the former two does not catch up with the internal change of reported task state definitions as the kernel evolves. IMHO, exporting internal representations of task state in the tracepoint sched_switch is not a good practice and not encouraged at all, which can easily break userspace tools that relies on it. Especially when tracepoints are massively used in many observability tools nowadays due to its stable nature, which makes them no longer used for debug only purpose and we should be careful to decide what ought to be reported to userspace and what ought not. Therefore, to fix the issues mentioned above for good, instead of choosing to sync the userspace tracing tools with the latest task states constants mapping, I proposed to replace reported task state in sched_switch with a symbolic character, and save the further processing of userspace tools and spare them from knowing further implementation details in the kernel. After this patch seires, we report 'RSDTtXZPI' the same as in procfs, plus a 'p' which denotes PREEMP_ACTIVE and is used for sched_switch tracepoint only. Reviews welcome! Regards, Ze Ze Gao (2): sched, tracing: report task state in symbolic chars instead perf sched: sync with latest sched_switch tracepoint definition include/trace/events/sched.h | 41 ++++++++++----------------- tools/perf/builtin-sched.c | 55 ++++++------------------------------ 2 files changed, 24 insertions(+), 72 deletions(-) Ze Gao (1): libtraceevent: sync with latest sched_switch tracepoint definition plugins/plugin_sched_switch.c | 23 +---------------------- 1 file changed, 1 insertion(+), 22 deletions(-)