[tip:tracing/urgent] tracing: Update the comm field in the right variable in update_max_tr
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From: tip-bot for Arnaldo Carvalho de Melo on 11 Mar 2010 09:40 Commit-ID: 1acaa1b2d9b5904c9cce06122990a2d71046ce16 Gitweb: http://git.kernel.org/tip/1acaa1b2d9b5904c9cce06122990a2d71046ce16 Author: Arnaldo Carvalho de Melo <acme(a)redhat.com> AuthorDate: Fri, 5 Mar 2010 18:23:50 -0300 Committer: Steven Rostedt <rostedt(a)goodmis.org> CommitDate: Fri, 5 Mar 2010 21:12:08 -0500 tracing: Update the comm field in the right variable in update_max_tr The latency output showed: # | task: -3 (uid:0 nice:0 policy:1 rt_prio:99) The comm is missing in the "task:" and it looks like a minus 3 is the output. The correct display should be: # | task: migration/0-3 (uid:0 nice:0 policy:1 rt_prio:99) The problem is that the comm is being stored in the wrong data structure. The max_tr.data[cpu] is what stores the comm, not the tr->data[cpu]. Before this patch the max_tr.data[cpu]->comm was zeroed and the /debug/trace ended up showing just the '-' sign followed by the pid. Also remove a needless initialization of max_data. Signed-off-by: Arnaldo Carvalho de Melo <acme(a)redhat.com> LKML-Reference: <1267824230-23861-1-git-send-email-acme(a)infradead.org> Signed-off-by: Steven Rostedt <rostedt(a)goodmis.org> --- kernel/trace/trace.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 032c57c..6efd5cb 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -592,7 +592,7 @@ static void __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) { struct trace_array_cpu *data = tr->data[cpu]; - struct trace_array_cpu *max_data = tr->data[cpu]; + struct trace_array_cpu *max_data; max_tr.cpu = cpu; max_tr.time_start = data->preempt_timestamp; @@ -602,7 +602,7 @@ __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) max_data->critical_start = data->critical_start; max_data->critical_end = data->critical_end; - memcpy(data->comm, tsk->comm, TASK_COMM_LEN); + memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); max_data->pid = tsk->pid; max_data->uid = task_uid(tsk); max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |