From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 62751C00140 for ; Mon, 15 Aug 2022 17:26:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231191AbiHOR03 (ORCPT ); Mon, 15 Aug 2022 13:26:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230092AbiHOR00 (ORCPT ); Mon, 15 Aug 2022 13:26:26 -0400 Received: from out0.migadu.com (out0.migadu.com [IPv6:2001:41d0:2:267::]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EF62EE0D6 for ; Mon, 15 Aug 2022 10:26:24 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1660584382; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=2ATDYH/fzJGrRFCJwgQnJvJlavn2n3Y9MC4NIhEqVrQ=; b=QSKJpbzucIobo/9f1eN92mvg54vCoczIXlY7xGAIjfLik0h9iBO16nz3Qe3i1jt40YRUGo 74Fkuk92RVkjP9Y7pzqAsGfGWellQnXBWz/53+bi5tdzUxRM/d3suvxLftDy4wn5dYHq6v BMSfjZKJRRtfOtg7pNU5pFR9I75V4kA= From: Kent Overstreet To: akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org, Kent Overstreet , Johannes Weiner , Michal Hocko , Roman Gushchin , Michal Hocko Subject: [PATCH 01/11] mm/memcontrol.c: Convert to printbuf Date: Mon, 15 Aug 2022 13:26:03 -0400 Message-Id: <20220815172613.621627-2-kent.overstreet@linux.dev> In-Reply-To: <20220815172613.621627-1-kent.overstreet@linux.dev> References: <20220815172613.621627-1-kent.overstreet@linux.dev> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Kent Overstreet This converts memory_stat_format() from seq_buf to printbuf. Printbuf is simalar to seq_buf except that it heap allocates the string buffer: here, we were already heap allocating the buffer with kmalloc() so the conversion is trivial. Signed-off-by: Kent Overstreet Cc: Johannes Weiner Cc: Michal Hocko Cc: Roman Gushchin Acked-by: Michal Hocko --- mm/memcontrol.c | 54 ++++++++++++++++++++++++------------------------- 1 file changed, 27 insertions(+), 27 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index b69979c9ce..54897e4ac4 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -62,7 +62,7 @@ #include #include #include -#include +#include #include "internal.h" #include #include @@ -1490,13 +1490,10 @@ static const unsigned int memcg_vm_event_stat[] = { #endif }; -static void memory_stat_format(struct mem_cgroup *memcg, char *buf, int bufsize) +static void memory_stat_format(struct printbuf *out, struct mem_cgroup *memcg) { - struct seq_buf s; int i; - seq_buf_init(&s, buf, bufsize); - /* * Provide statistics on the state of the memory subsystem as * well as cumulative event counters that show past behavior. @@ -1513,30 +1510,30 @@ static void memory_stat_format(struct mem_cgroup *memcg, char *buf, int bufsize) u64 size; size = memcg_page_state_output(memcg, memory_stats[i].idx); - seq_buf_printf(&s, "%s %llu\n", memory_stats[i].name, size); + prt_printf(out, "%s %llu\n", memory_stats[i].name, size); if (unlikely(memory_stats[i].idx == NR_SLAB_UNRECLAIMABLE_B)) { size += memcg_page_state_output(memcg, NR_SLAB_RECLAIMABLE_B); - seq_buf_printf(&s, "slab %llu\n", size); + prt_printf(out, "slab %llu\n", size); } } /* Accumulated memory events */ - seq_buf_printf(&s, "pgscan %lu\n", - memcg_events(memcg, PGSCAN_KSWAPD) + - memcg_events(memcg, PGSCAN_DIRECT)); - seq_buf_printf(&s, "pgsteal %lu\n", - memcg_events(memcg, PGSTEAL_KSWAPD) + - memcg_events(memcg, PGSTEAL_DIRECT)); + prt_printf(out, "pgscan %lu\n", + memcg_events(memcg, PGSCAN_KSWAPD) + + memcg_events(memcg, PGSCAN_DIRECT)); + prt_printf(out, "pgsteal %lu\n", + memcg_events(memcg, PGSTEAL_KSWAPD) + + memcg_events(memcg, PGSTEAL_DIRECT)); for (i = 0; i < ARRAY_SIZE(memcg_vm_event_stat); i++) - seq_buf_printf(&s, "%s %lu\n", - vm_event_name(memcg_vm_event_stat[i]), - memcg_events(memcg, memcg_vm_event_stat[i])); + prt_printf(out, "%s %lu\n", + vm_event_name(memcg_vm_event_stat[i]), + memcg_events(memcg, memcg_vm_event_stat[i])); /* The above should easily fit into one page */ - WARN_ON_ONCE(seq_buf_has_overflowed(&s)); + WARN_ON_ONCE(!printbuf_remaining(out)); } #define K(x) ((x) << (PAGE_SHIFT-10)) @@ -1573,7 +1570,8 @@ void mem_cgroup_print_oom_context(struct mem_cgroup *memcg, struct task_struct * void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg) { /* Use static buffer, for the caller is holding oom_lock. */ - static char buf[PAGE_SIZE]; + static char _buf[PAGE_SIZE]; + struct printbuf buf = PRINTBUF_EXTERN(_buf, sizeof(_buf)); lockdep_assert_held(&oom_lock); @@ -1596,8 +1594,8 @@ void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg) pr_info("Memory cgroup stats for "); pr_cont_cgroup_path(memcg->css.cgroup); pr_cont(":"); - memory_stat_format(memcg, buf, sizeof(buf)); - pr_info("%s", buf); + memory_stat_format(&buf, memcg); + pr_info("%s", buf.buf); } /* @@ -6401,14 +6399,16 @@ static int memory_events_local_show(struct seq_file *m, void *v) static int memory_stat_show(struct seq_file *m, void *v) { struct mem_cgroup *memcg = mem_cgroup_from_seq(m); - char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL); + struct printbuf buf = PRINTBUF; + int ret; - if (!buf) - return -ENOMEM; - memory_stat_format(memcg, buf, PAGE_SIZE); - seq_puts(m, buf); - kfree(buf); - return 0; + memory_stat_format(&buf, memcg); + ret = buf.allocation_failure ? -ENOMEM : 0; + if (!ret) + seq_puts(m, buf.buf); + + printbuf_exit(&buf); + return ret; } #ifdef CONFIG_NUMA -- 2.36.1