From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755280AbcFHBse (ORCPT ); Tue, 7 Jun 2016 21:48:34 -0400 Received: from mail-wm0-f66.google.com ([74.125.82.66]:33564 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752775AbcFHBsc (ORCPT ); Tue, 7 Jun 2016 21:48:32 -0400 MIME-Version: 1.0 In-Reply-To: <20160608001625.GB27258@bbox> References: <1465289804-4913-1-git-send-email-opensource.ganesh@gmail.com> <20160608001625.GB27258@bbox> From: Ganesh Mahendran Date: Wed, 8 Jun 2016 09:48:30 +0800 Message-ID: Subject: Re: [PATCH] mm/zsmalloc: add trace events for zs_compact To: Minchan Kim Cc: Linux-MM , linux-kernel , Andrew Morton , Nitin Gupta , Sergey Senozhatsky , rostedt@goodmis.org, mingo@redhat.com Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Minchan: 2016-06-08 8:16 GMT+08:00 Minchan Kim : > 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. 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 >> --- >> 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 >> +#include >> + >> +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 >> 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 >> #include >> #include >> @@ -52,6 +54,7 @@ >> #include >> #include >> #include >> +#include >> >> #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 >>