On Thu, Mar 19, 2015 at 11:04:30AM +0800, Xie XiuQi wrote:
> Memory-failure as the high level machine check handler, it's necessary
> to report memory page recovery action result to user space by ftrace.
>
> This patch add a event at ras group for memory-failure.
>
> The output like below:
> # tracer: nop
> #
> # entries-in-buffer/entries-written: 2/2 #P:24
> #
> # _-----=> irqs-off
> # / _----=> need-resched
> # | / _---=> hardirq/softirq
> # || / _--=> preempt-depth
> # ||| / delay
> # TASK-PID CPU# |||| TIMESTAMP FUNCTION
> # | | | |||| | |
> mce-inject-13150 [001] .... 277.019359: memory_failure_event: pfn 0x19869: free buddy page recovery: Delayed
>
> ---
> v1->v2:
> - Comment update
> - Just passing 'result' instead of 'action_name[result]',
> suggested by Steve. And hard coded there because trace-cmd
> and perf do not have a way to process enums.
>
> Cc: Tony Luck <tony.luck@xxxxxxxxx>
> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
> Signed-off-by: Xie XiuQi <xiexiuqi@xxxxxxxxxx>
> ---
> include/ras/ras_event.h | 38 ++++++++++++++++++++++++++++++++++++++
> mm/memory-failure.c | 3 +++
> 2 files changed, 41 insertions(+)
>
> diff --git a/include/ras/ras_event.h b/include/ras/ras_event.h
> index 79abb9c..ebb05f3 100644
> --- a/include/ras/ras_event.h
> +++ b/include/ras/ras_event.h
> @@ -232,6 +232,44 @@ TRACE_EVENT(aer_event,
> __print_flags(__entry->status, "|", aer_uncorrectable_errors))
> );
>
> +/*
> + * memory-failure recovery action result event
> + *
> + * unsigned long pfn - Page Number of the corrupted page
> + * char * action - Recovery action for various type of pages
> + * int result - Action result
> + *
> + * NOTE: 'action' and 'result' are defined at mm/memory-failure.c
> + */
> +TRACE_EVENT(memory_failure_event,
What is the real reason for adding this TP? Real-life use cases please.
Add those to the commit message too.
"Just because" is not a proper justification.
> + TP_PROTO(const unsigned long pfn,
> + const char *action,
> + const int result),
> +
> + TP_ARGS(pfn, action, result),
> +
> + TP_STRUCT__entry(
> + __field(unsigned long, pfn)
> + __string(action, action)
> + __field(int, result)
> + ),
> +
> + TP_fast_assign(
> + __entry->pfn = pfn;
> + __assign_str(action, action);
> + __entry->result = result;
> + ),
> +
> + TP_printk("pfn %#lx: %s page recovery: %s",
> + __entry->pfn,
> + __get_str(action),
> + __print_symbolic(__entry->result,
> + {0, "Ignored"},
> + {1, "Failed"},
> + {2, "Delayed"},
> + {3, "Recovered"})
If you're going to do this, please add a comment above it like this:
/*
* Keep those in sync with static const char *action_name[] in
* mm/memory-failure.c
*/
Thanks.
--
Regards/Gruss,
Boris.
ECO tip #101: Trim your mails when you reply.
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