From: Ovidiu Panait <ovidiu.panait@xxxxxxxxxxxxx> Subject: mm, tracing: improve rss_stat tracepoint message Adjust the rss_stat tracepoint to print the name of the resident page type that got updated (e.g. MM_ANONPAGES/MM_FILEPAGES), rather than the numeric index corresponding to it (the __entry->member value): Before this patch: ------------------ rss_stat: mm_id=1216113068 curr=0 member=1 size=28672B rss_stat: mm_id=1216113068 curr=0 member=1 size=0B rss_stat: mm_id=534402304 curr=1 member=0 size=188416B rss_stat: mm_id=534402304 curr=1 member=1 size=40960B After this patch: ----------------- rss_stat: mm_id=1726253524 curr=1 type=MM_ANONPAGES size=40960B rss_stat: mm_id=1726253524 curr=1 type=MM_FILEPAGES size=663552B rss_stat: mm_id=1726253524 curr=1 type=MM_ANONPAGES size=65536B rss_stat: mm_id=1726253524 curr=1 type=MM_FILEPAGES size=647168B Use TRACE_DEFINE_ENUM()/__print_symbolic() logic to map the enum values to the strings they represent, so that userspace tools can also parse the raw data correctly. Link: https://lkml.kernel.org/r/20210310162305.4862-1-ovidiu.panait@xxxxxxxxxxxxx Signed-off-by: Ovidiu Panait <ovidiu.panait@xxxxxxxxxxxxx> Suggested-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx> Reviewed-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/trace/events/kmem.h | 24 ++++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-) --- a/include/trace/events/kmem.h~mm-tracing-improve-rss_stat-tracepoint-message +++ a/include/trace/events/kmem.h @@ -343,6 +343,26 @@ static unsigned int __maybe_unused mm_pt #define __PTR_TO_HASHVAL #endif +#define TRACE_MM_PAGES \ + EM(MM_FILEPAGES) \ + EM(MM_ANONPAGES) \ + EM(MM_SWAPENTS) \ + EMe(MM_SHMEMPAGES) + +#undef EM +#undef EMe + +#define EM(a) TRACE_DEFINE_ENUM(a); +#define EMe(a) TRACE_DEFINE_ENUM(a); + +TRACE_MM_PAGES + +#undef EM +#undef EMe + +#define EM(a) { a, #a }, +#define EMe(a) { a, #a } + TRACE_EVENT(rss_stat, TP_PROTO(struct mm_struct *mm, @@ -365,10 +385,10 @@ TRACE_EVENT(rss_stat, __entry->size = (count << PAGE_SHIFT); ), - TP_printk("mm_id=%u curr=%d member=%d size=%ldB", + TP_printk("mm_id=%u curr=%d type=%s size=%ldB", __entry->mm_id, __entry->curr, - __entry->member, + __print_symbolic(__entry->member, TRACE_MM_PAGES), __entry->size) ); #endif /* _TRACE_KMEM_H */ _
