From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f174.google.com (mail-pd0-f174.google.com [209.85.192.174]) by kanga.kvack.org (Postfix) with ESMTP id 4079A2802A5 for ; Mon, 6 Jul 2015 08:19:00 -0400 (EDT) Received: by pddu5 with SMTP id u5so17832409pdd.3 for ; Mon, 06 Jul 2015 05:19:00 -0700 (PDT) Received: from mail-pd0-x231.google.com (mail-pd0-x231.google.com. [2607:f8b0:400e:c02::231]) by mx.google.com with ESMTPS id qg11si28822488pab.141.2015.07.06.05.18.59 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 06 Jul 2015 05:18:59 -0700 (PDT) Received: by pddu5 with SMTP id u5so17832243pdd.3 for ; Mon, 06 Jul 2015 05:18:59 -0700 (PDT) From: Sergey Senozhatsky Subject: [PATCH v5 2/7] zsmalloc: always keep per-class stats Date: Mon, 6 Jul 2015 21:17:45 +0900 Message-Id: <1436185070-1940-3-git-send-email-sergey.senozhatsky@gmail.com> In-Reply-To: <1436185070-1940-1-git-send-email-sergey.senozhatsky@gmail.com> References: <1436185070-1940-1-git-send-email-sergey.senozhatsky@gmail.com> Sender: owner-linux-mm@kvack.org List-ID: To: Minchan Kim Cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Sergey@kvack.org, "Senozhatsky Always account per-class `zs_size_stat' stats. This data will help us make better decisions during compaction. We are especially interested in OBJ_ALLOCATED and OBJ_USED, which can tell us if class compaction will result in any memory gain. For instance, we know the number of allocated objects in the class, the number of objects being used (so we also know how many objects are not used) and the number of objects per-page. So we can ensure if we have enough unused objects to form at least one ZS_EMPTY zspage during compaction. We calculate this value on per-class basis so we can calculate a total number of zspages that can be released. Which is exactly what a shrinker wants to know. Signed-off-by: Sergey Senozhatsky Acked-by: Minchan Kim --- mm/zsmalloc.c | 48 ++++++++++++------------------------------------ 1 file changed, 12 insertions(+), 36 deletions(-) diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index 2aecdb3..036baa8 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -169,14 +169,12 @@ enum zs_stat_type { NR_ZS_STAT_TYPE, }; -#ifdef CONFIG_ZSMALLOC_STAT - -static struct dentry *zs_stat_root; - struct zs_size_stat { unsigned long objs[NR_ZS_STAT_TYPE]; }; +#ifdef CONFIG_ZSMALLOC_STAT +static struct dentry *zs_stat_root; #endif /* @@ -201,25 +199,21 @@ static int zs_size_classes; static const int fullness_threshold_frac = 4; struct size_class { + spinlock_t lock; + struct page *fullness_list[_ZS_NR_FULLNESS_GROUPS]; /* * Size of objects stored in this class. Must be multiple * of ZS_ALIGN. */ - int size; - unsigned int index; + int size; + unsigned int index; /* Number of PAGE_SIZE sized pages to combine to form a 'zspage' */ - int pages_per_zspage; - /* huge object: pages_per_zspage == 1 && maxobj_per_zspage == 1 */ - bool huge; - -#ifdef CONFIG_ZSMALLOC_STAT - struct zs_size_stat stats; -#endif - - spinlock_t lock; + int pages_per_zspage; + struct zs_size_stat stats; - struct page *fullness_list[_ZS_NR_FULLNESS_GROUPS]; + /* huge object: pages_per_zspage == 1 && maxobj_per_zspage == 1 */ + bool huge; }; /* @@ -441,8 +435,6 @@ static int get_size_class_index(int size) return min(zs_size_classes - 1, idx); } -#ifdef CONFIG_ZSMALLOC_STAT - static inline void zs_stat_inc(struct size_class *class, enum zs_stat_type type, unsigned long cnt) { @@ -461,6 +453,8 @@ static inline unsigned long zs_stat_get(struct size_class *class, return class->stats.objs[type]; } +#ifdef CONFIG_ZSMALLOC_STAT + static int __init zs_stat_init(void) { if (!debugfs_initialized()) @@ -576,23 +570,6 @@ static void zs_pool_stat_destroy(struct zs_pool *pool) } #else /* CONFIG_ZSMALLOC_STAT */ - -static inline void zs_stat_inc(struct size_class *class, - enum zs_stat_type type, unsigned long cnt) -{ -} - -static inline void zs_stat_dec(struct size_class *class, - enum zs_stat_type type, unsigned long cnt) -{ -} - -static inline unsigned long zs_stat_get(struct size_class *class, - enum zs_stat_type type) -{ - return 0; -} - static int __init zs_stat_init(void) { return 0; @@ -610,7 +587,6 @@ static inline int zs_pool_stat_create(char *name, struct zs_pool *pool) static inline void zs_pool_stat_destroy(struct zs_pool *pool) { } - #endif -- 2.5.0.rc0.3.g912bd49 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org