From a6a8cdfdde43b6231dd1ed61b8a7a6ee55956376 Mon Sep 17 00:00:00 2001 From: Chengming Zhou Date: Tue, 20 Feb 2024 06:53:00 +0000 Subject: mm/zsmalloc: remove set_zspage_mapping() Patch series "mm/zsmalloc: some cleanup for get/set_zspage_mapping()". The discussion[1] with Sergey shows there are some cleanup works to do in get/set_zspage_mapping(): - the fullness returned from get_zspage_mapping() is not stable outside pool->lock, this usage pattern is confusing, but should be ok in this free_zspage path. - we seldom use the class_idx returned from get_zspage_mapping(), only free_zspage path use to get its class. - set_zspage_mapping() always set the zspage->class, but it's never changed after zspage allocated. [1] https://lore.kernel.org/all/a6c22e30-cf10-4122-91bc-ceb9fb57a5d6@bytedance.com/ This patch (of 3): We only need to update zspage->fullness when insert_zspage(), since zspage->class is never changed after allocated. Link: https://lkml.kernel.org/r/20240220-b4-zsmalloc-cleanup-v1-0-5c5ee4ccdd87@bytedance.com Link: https://lkml.kernel.org/r/20240220-b4-zsmalloc-cleanup-v1-1-5c5ee4ccdd87@bytedance.com Signed-off-by: Chengming Zhou Reviewed-by: Sergey Senozhatsky Cc: Johannes Weiner Cc: Minchan Kim Cc: Nhat Pham Cc: Yosry Ahmed Signed-off-by: Andrew Morton --- mm/zsmalloc.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) (limited to 'mm/zsmalloc.c') diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index a48f4651d143..a6653915bf17 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -486,14 +486,6 @@ static struct size_class *zspage_class(struct zs_pool *pool, return pool->size_class[zspage->class]; } -static void set_zspage_mapping(struct zspage *zspage, - unsigned int class_idx, - int fullness) -{ - zspage->class = class_idx; - zspage->fullness = fullness; -} - /* * zsmalloc divides the pool into various size classes where each * class maintains a list of zspages where each zspage is divided @@ -688,6 +680,7 @@ static void insert_zspage(struct size_class *class, { class_stat_inc(class, fullness, 1); list_add(&zspage->list, &class->fullness_list[fullness]); + zspage->fullness = fullness; } /* @@ -725,7 +718,6 @@ static int fix_fullness_group(struct size_class *class, struct zspage *zspage) remove_zspage(class, zspage, currfg); insert_zspage(class, zspage, newfg); - set_zspage_mapping(zspage, class_idx, newfg); out: return newfg; } @@ -1005,6 +997,7 @@ static struct zspage *alloc_zspage(struct zs_pool *pool, create_page_chain(class, zspage, pages); init_zspage(class, zspage); zspage->pool = pool; + zspage->class = class->index; return zspage; } @@ -1397,7 +1390,6 @@ unsigned long zs_malloc(struct zs_pool *pool, size_t size, gfp_t gfp) obj = obj_malloc(pool, zspage, handle); newfg = get_fullness_group(class, zspage); insert_zspage(class, zspage, newfg); - set_zspage_mapping(zspage, class->index, newfg); record_obj(handle, obj); atomic_long_add(class->pages_per_zspage, &pool->pages_allocated); class_stat_inc(class, ZS_OBJS_ALLOCATED, class->objs_per_zspage); @@ -1655,7 +1647,6 @@ static int putback_zspage(struct size_class *class, struct zspage *zspage) fullness = get_fullness_group(class, zspage); insert_zspage(class, zspage, fullness); - set_zspage_mapping(zspage, class->index, fullness); return fullness; } -- cgit v1.2.3-70-g09d2