From patchwork Wed Nov 22 23:25:07 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kent Overstreet X-Patchwork-Id: 13465559 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4EF15C61DA7 for ; Wed, 22 Nov 2023 23:25:32 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id AF77B6B05EC; Wed, 22 Nov 2023 18:25:30 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id A801A6B05ED; Wed, 22 Nov 2023 18:25:30 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8F8A46B05EE; Wed, 22 Nov 2023 18:25:30 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 771186B05EC for ; Wed, 22 Nov 2023 18:25:30 -0500 (EST) Received: from smtpin07.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 43D63160FC6 for ; Wed, 22 Nov 2023 23:25:30 +0000 (UTC) X-FDA: 81487174020.07.E1BC926 Received: from out-173.mta0.migadu.com (out-173.mta0.migadu.com [91.218.175.173]) by imf20.hostedemail.com (Postfix) with ESMTP id 7D2CA1C000C for ; Wed, 22 Nov 2023 23:25:28 +0000 (UTC) Authentication-Results: imf20.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=RwDGCsBx; spf=pass (imf20.hostedemail.com: domain of kent.overstreet@linux.dev designates 91.218.175.173 as permitted sender) smtp.mailfrom=kent.overstreet@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1700695528; a=rsa-sha256; cv=none; b=3I8ScfTdV1QQ42AmYI+a7DBiti1qAJxEwboReUM56qIGdhcMWP6ymO+2v2RaRMkWm1Ij8y wS0AQGv8XKkCepisDAxh1DSMmeAVNbvao1T4UuLELJ/sjXlsQ+RNdaeNQsAqPdTomgzGdQ 8J9sA4vF53pg3vPU2wvDMXR/e0Ql4to= ARC-Authentication-Results: i=1; imf20.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=RwDGCsBx; spf=pass (imf20.hostedemail.com: domain of kent.overstreet@linux.dev designates 91.218.175.173 as permitted sender) smtp.mailfrom=kent.overstreet@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1700695528; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=ce6mQdeWYA7JZiZSelXeyRte1bT790UpclDUySrWbbI=; b=47Rl9bGYvh3RVveyUdHlWpu+9lRsYTph4bL7RtD6pqCah9360Qa7K1s9V5Gs9XJGP8ue5T 13HN0mfBvVx4EHARHrcKghtTagh1AN/owNpzOvem5Bgt+69eq8BidaqdgM+JJtZwEW+Lxz RjhYRrQMo+gpcRl2qfyyfzZj5q0+O3s= 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=1700695527; 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=ce6mQdeWYA7JZiZSelXeyRte1bT790UpclDUySrWbbI=; b=RwDGCsBxUOAeC14xj7ENLjAvR8IPMtphog88OnO0JhzfsIcs+mraOc5OHgWapTIGcLSRsp Eu6N2oJ5sNyByGKgzowShHq/oDCtx/SHNWZszz3Jq5vB9+XfTDyzs5kpuj8NlrxAXhVCaG bk8karUNujFdsVJa4kR7ZHnGQ3NZheM= From: Kent Overstreet To: linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: Kent Overstreet , Andrew Morton , Qi Zheng , Roman Gushchin Subject: [PATCH 2/7] mm: shrinker: Add a .to_text() method for shrinkers Date: Wed, 22 Nov 2023 18:25:07 -0500 Message-ID: <20231122232515.177833-3-kent.overstreet@linux.dev> In-Reply-To: <20231122232515.177833-1-kent.overstreet@linux.dev> References: <20231122232515.177833-1-kent.overstreet@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 7D2CA1C000C X-Stat-Signature: gpcucxrj7cbm4rfxztrk7ddwfbrpx7g6 X-Rspam-User: X-HE-Tag: 1700695528-132450 X-HE-Meta: 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 V5S4SLha IZ6GhBmxrj4hvZGxWINH6EIFagDYqViQ2NQXPT4UigJHEenglBxboBAX3z6ffH3/huVzAFR3YCUWW3MwF5gRgOvxffFboZqLCXANm9Um6jD36LO6rjGw8sLMsLvjzDtIE0lOcGZgrPiMJf1E4uC0pIiBiU8PWvRjezvQquRcN7LBMSWnRYi3226xq/GCEkqIuJUFETnxocoBCwQvYlamgQhYo/GPVmtqx5hreKdpRlrn3c7QybAazYNWE6OrpixYw6rMj/FK0/k/f2eX7QKV/SMJl5VGosqHlHkI9gnUl2MtlszG7QqblI9wSBQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: This adds a new callback method to shrinkers which they can use to describe anything relevant to memory reclaim about their internal state, for example object dirtyness. This patch also adds shrinkers_to_text(), which reports on the top 10 shrinkers - by object count - in sorted order, to be used in OOM reporting. Cc: Andrew Morton Cc: Qi Zheng Cc: Roman Gushchin Cc: linux-mm@kvack.org Signed-off-by: Kent Overstreet --- include/linux/shrinker.h | 6 +++- mm/shrinker.c | 73 +++++++++++++++++++++++++++++++++++++++- 2 files changed, 77 insertions(+), 2 deletions(-) diff --git a/include/linux/shrinker.h b/include/linux/shrinker.h index 1a00be90d93a..968c55474e78 100644 --- a/include/linux/shrinker.h +++ b/include/linux/shrinker.h @@ -24,6 +24,8 @@ struct shrinker_info { struct shrinker_info_unit *unit[]; }; +struct seq_buf; + /* * This struct is used to pass information from page reclaim to the shrinkers. * We consolidate the values for easier extension later. @@ -80,10 +82,12 @@ struct shrink_control { * @flags determine the shrinker abilities, like numa awareness */ struct shrinker { + const char *name; unsigned long (*count_objects)(struct shrinker *, struct shrink_control *sc); unsigned long (*scan_objects)(struct shrinker *, struct shrink_control *sc); + void (*to_text)(struct seq_buf *, struct shrinker *); long batch; /* reclaim batch size, 0 = default */ int seeks; /* seeks to recreate an obj */ @@ -110,7 +114,6 @@ struct shrinker { #endif #ifdef CONFIG_SHRINKER_DEBUG int debugfs_id; - const char *name; struct dentry *debugfs_entry; #endif /* objs pending delete, per node */ @@ -135,6 +138,7 @@ __printf(2, 3) struct shrinker *shrinker_alloc(unsigned int flags, const char *fmt, ...); void shrinker_register(struct shrinker *shrinker); void shrinker_free(struct shrinker *shrinker); +void shrinkers_to_text(struct seq_buf *); static inline bool shrinker_try_get(struct shrinker *shrinker) { diff --git a/mm/shrinker.c b/mm/shrinker.c index dd91eab43ed3..4976dbac4c83 100644 --- a/mm/shrinker.c +++ b/mm/shrinker.c @@ -1,8 +1,9 @@ // SPDX-License-Identifier: GPL-2.0 #include +#include #include +#include #include -#include #include #include "internal.h" @@ -807,3 +808,73 @@ void shrinker_free(struct shrinker *shrinker) call_rcu(&shrinker->rcu, shrinker_free_rcu_cb); } EXPORT_SYMBOL_GPL(shrinker_free); + +void shrinker_to_text(struct seq_buf *out, struct shrinker *shrinker) +{ + struct shrink_control sc = { .gfp_mask = GFP_KERNEL, }; + + seq_buf_puts(out, shrinker->name); + seq_buf_printf(out, " objects: %lu\n", shrinker->count_objects(shrinker, &sc)); + + if (shrinker->to_text) { + shrinker->to_text(out, shrinker); + seq_buf_puts(out, "\n"); + } +} + +/** + * shrinkers_to_text - Report on shrinkers with highest usage + * + * This reports on the top 10 shrinkers, by object counts, in sorted order: + * intended to be used for OOM reporting. + */ +void shrinkers_to_text(struct seq_buf *out) +{ + struct shrinker *shrinker; + struct shrinker_by_mem { + struct shrinker *shrinker; + unsigned long mem; + } shrinkers_by_mem[10]; + int i, nr = 0; + + if (!mutex_trylock(&shrinker_mutex)) { + seq_buf_puts(out, "(couldn't take shrinker lock)"); + return; + } + + list_for_each_entry(shrinker, &shrinker_list, list) { + struct shrink_control sc = { .gfp_mask = GFP_KERNEL, }; + unsigned long mem = shrinker->count_objects(shrinker, &sc); + + if (!mem || mem == SHRINK_STOP || mem == SHRINK_EMPTY) + continue; + + for (i = 0; i < nr; i++) + if (mem < shrinkers_by_mem[i].mem) + break; + + if (nr < ARRAY_SIZE(shrinkers_by_mem)) { + memmove(&shrinkers_by_mem[i + 1], + &shrinkers_by_mem[i], + sizeof(shrinkers_by_mem[0]) * (nr - i)); + nr++; + } else if (i) { + i--; + memmove(&shrinkers_by_mem[0], + &shrinkers_by_mem[1], + sizeof(shrinkers_by_mem[0]) * i); + } else { + continue; + } + + shrinkers_by_mem[i] = (struct shrinker_by_mem) { + .shrinker = shrinker, + .mem = mem, + }; + } + + for (i = nr - 1; i >= 0; --i) + shrinker_to_text(out, shrinkers_by_mem[i].shrinker); + + mutex_unlock(&shrinker_mutex); +}