On Wed, Jun 08, 2016 at 09:48:30AM +0800, Ganesh Mahendran wrote: > Hi, Minchan: > > 2016-06-08 8:16 GMT+08:00 Minchan Kim <minchan@xxxxxxxxxx>: > > Hello Ganesh, > > > > On Tue, Jun 07, 2016 at 04:56:44PM +0800, Ganesh Mahendran wrote: > >> Currently zsmalloc is widely used in android device. > >> Sometimes, we want to see how frequently zs_compact is > >> triggered or how may pages freed by zs_compact(), or which > >> zsmalloc pool is compacted. > >> > >> Most of the time, user can get the brief information from > >> trace_mm_shrink_slab_[start | end], but in some senario, > >> they do not use zsmalloc shrinker, but trigger compaction manually. > >> So add some trace events in zs_compact is convenient. Also we > >> can add some zsmalloc specific information(pool name, total compact > >> pages, etc) in zsmalloc trace. > > > > Sorry, I cannot understand what's the problem now and what you want to > > solve. Could you elaborate it a bit? > > > > Thanks. > > We have backported the zs_compact() to our product(kernel 3.18). > It is usefull for a longtime running device. > But there is not a convenient way to get the detailed information > of zs_comapct() which is usefull for performance optimization. > Information about how much time zs_compact used, which pool is > compacted, how many page freed, etc. You can know how many pages are freed by object compaction via mm_stat each /sys/block/zram-id/mm_stat. And you can use function_graph to know how much time zs_compact used. > With these information, we will know what is going on in zs_comapct. > And draw the relation between free mem and zs_comapct. > > > > >> > >> This patch add two trace events for zs_compact(), below the trace log: > >> ----------------------------- > >> root@land:/ # cat /d/tracing/trace > >> kswapd0-125 [007] ...1 174.176979: zsmalloc_compact_start: pool zram0 > >> kswapd0-125 [007] ...1 174.181967: zsmalloc_compact_end: pool zram0: 608 pages compacted(total 1794) > >> kswapd0-125 [000] ...1 184.134475: zsmalloc_compact_start: pool zram0 > >> kswapd0-125 [000] ...1 184.135010: zsmalloc_compact_end: pool zram0: 62 pages compacted(total 1856) > >> kswapd0-125 [003] ...1 226.927221: zsmalloc_compact_start: pool zram0 > >> kswapd0-125 [003] ...1 226.928575: zsmalloc_compact_end: pool zram0: 250 pages compacted(total 2106) > >> ----------------------------- > >> > >> Signed-off-by: Ganesh Mahendran <opensource.ganesh@xxxxxxxxx> > >> --- > >> include/trace/events/zsmalloc.h | 56 +++++++++++++++++++++++++++++++++++++++++ > >> mm/zsmalloc.c | 10 ++++++++ > >> 2 files changed, 66 insertions(+) > >> create mode 100644 include/trace/events/zsmalloc.h > >> > >> diff --git a/include/trace/events/zsmalloc.h b/include/trace/events/zsmalloc.h > >> new file mode 100644 > >> index 0000000..3b6f14e > >> --- /dev/null > >> +++ b/include/trace/events/zsmalloc.h > >> @@ -0,0 +1,56 @@ > >> +#undef TRACE_SYSTEM > >> +#define TRACE_SYSTEM zsmalloc > >> + > >> +#if !defined(_TRACE_ZSMALLOC_H) || defined(TRACE_HEADER_MULTI_READ) > >> +#define _TRACE_ZSMALLOC_H > >> + > >> +#include <linux/types.h> > >> +#include <linux/tracepoint.h> > >> + > >> +TRACE_EVENT(zsmalloc_compact_start, > >> + > >> + TP_PROTO(const char *pool_name), > >> + > >> + TP_ARGS(pool_name), > >> + > >> + TP_STRUCT__entry( > >> + __field(const char *, pool_name) > >> + ), > >> + > >> + TP_fast_assign( > >> + __entry->pool_name = pool_name; > >> + ), > >> + > >> + TP_printk("pool %s", > >> + __entry->pool_name) > >> +); > >> + > >> +TRACE_EVENT(zsmalloc_compact_end, > >> + > >> + TP_PROTO(const char *pool_name, unsigned long pages_compacted, > >> + unsigned long pages_total_compacted), > >> + > >> + TP_ARGS(pool_name, pages_compacted, pages_total_compacted), > >> + > >> + TP_STRUCT__entry( > >> + __field(const char *, pool_name) > >> + __field(unsigned long, pages_compacted) > >> + __field(unsigned long, pages_total_compacted) > >> + ), > >> + > >> + TP_fast_assign( > >> + __entry->pool_name = pool_name; > >> + __entry->pages_compacted = pages_compacted; > >> + __entry->pages_total_compacted = pages_total_compacted; > >> + ), > >> + > >> + TP_printk("pool %s: %ld pages compacted(total %ld)", > >> + __entry->pool_name, > >> + __entry->pages_compacted, > >> + __entry->pages_total_compacted) > >> +); > >> + > >> +#endif /* _TRACE_ZSMALLOC_H */ > >> + > >> +/* This part must be outside protection */ > >> +#include <trace/define_trace.h> > >> diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c > >> index 213d0e1..441b9f7 100644 > >> --- a/mm/zsmalloc.c > >> +++ b/mm/zsmalloc.c > >> @@ -30,6 +30,8 @@ > >> > >> #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > >> > >> +#define CREATE_TRACE_POINTS > >> + > >> #include <linux/module.h> > >> #include <linux/kernel.h> > >> #include <linux/sched.h> > >> @@ -52,6 +54,7 @@ > >> #include <linux/mount.h> > >> #include <linux/compaction.h> > >> #include <linux/pagemap.h> > >> +#include <trace/events/zsmalloc.h> > >> > >> #define ZSPAGE_MAGIC 0x58 > >> > >> @@ -2330,6 +2333,9 @@ unsigned long zs_compact(struct zs_pool *pool) > >> { > >> int i; > >> struct size_class *class; > >> + unsigned long pages_compacted_before = pool->stats.pages_compacted; > >> + > >> + trace_zsmalloc_compact_start(pool->name); > >> > >> for (i = zs_size_classes - 1; i >= 0; i--) { > >> class = pool->size_class[i]; > >> @@ -2340,6 +2346,10 @@ unsigned long zs_compact(struct zs_pool *pool) > >> __zs_compact(pool, class); > >> } > >> > >> + trace_zsmalloc_compact_end(pool->name, > >> + pool->stats.pages_compacted - pages_compacted_before, > >> + pool->stats.pages_compacted); > >> + > >> return pool->stats.pages_compacted; > >> } > >> EXPORT_SYMBOL_GPL(zs_compact); > >> -- > >> 1.9.1 > >> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. 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