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 X-Spam-Level: X-Spam-Status: No, score=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 65B78C433DF for ; Tue, 4 Aug 2020 14:26:16 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1FE6922B42 for ; Tue, 4 Aug 2020 14:26:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b="NK3YZMpG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1FE6922B42 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=amazon.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A7F998D0165; Tue, 4 Aug 2020 10:26:15 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A31748D0081; Tue, 4 Aug 2020 10:26:15 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 921248D0165; Tue, 4 Aug 2020 10:26:15 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0227.hostedemail.com [216.40.44.227]) by kanga.kvack.org (Postfix) with ESMTP id 7CC388D0081 for ; Tue, 4 Aug 2020 10:26:15 -0400 (EDT) Received: from smtpin03.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 3DDE0181AEF09 for ; Tue, 4 Aug 2020 14:26:15 +0000 (UTC) X-FDA: 77113111110.03.fang80_1e0646626fa7 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin03.hostedemail.com (Postfix) with ESMTP id 32C0828A26E for ; Tue, 4 Aug 2020 14:26:09 +0000 (UTC) X-HE-Tag: fang80_1e0646626fa7 X-Filterd-Recvd-Size: 9667 Received: from smtp-fw-4101.amazon.com (smtp-fw-4101.amazon.com [72.21.198.25]) by imf04.hostedemail.com (Postfix) with ESMTP for ; Tue, 4 Aug 2020 14:26:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1596551169; x=1628087169; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version; bh=w/dElk34eSRGm8oboxKmrsE7ynyuF8ZsouOb6Mao4uk=; b=NK3YZMpG/brqy4yDFL3aDlNTxPjsM3AGtPPbAFkHqexCnXkqZf4XD8KA 0pHECZ0FZFHQRiMYhjFiTArKqqg0NSiiwRar2y9J2ZHjyJvFeiGKLPzYb TydFwytlm749ZbkkBTQ+8Jf5aKsutV0WMRppeRbR38lVd/y9J9igNdpAC I=; IronPort-SDR: UicNHCMVZVdWSqr5ILmo6MyYe1RtJdTJ8s6et3k26W4vUc+xkP+UDNDo/AugRRr4E4DLNSSyWQ h98I3eBetyjg== X-IronPort-AV: E=Sophos;i="5.75,434,1589241600"; d="scan'208";a="46072356" Received: from iad12-co-svc-p1-lb1-vlan3.amazon.com (HELO email-inbound-relay-2c-168cbb73.us-west-2.amazon.com) ([10.43.8.6]) by smtp-border-fw-out-4101.iad4.amazon.com with ESMTP; 04 Aug 2020 14:26:04 +0000 Received: from EX13MTAUEA002.ant.amazon.com (pdx4-ws-svc-p6-lb7-vlan2.pdx.amazon.com [10.170.41.162]) by email-inbound-relay-2c-168cbb73.us-west-2.amazon.com (Postfix) with ESMTPS id 20ADAA2209; Tue, 4 Aug 2020 14:26:02 +0000 (UTC) Received: from EX13D31EUA001.ant.amazon.com (10.43.165.15) by EX13MTAUEA002.ant.amazon.com (10.43.61.77) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 4 Aug 2020 14:26:01 +0000 Received: from u886c93fd17d25d.ant.amazon.com (10.43.161.203) by EX13D31EUA001.ant.amazon.com (10.43.165.15) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 4 Aug 2020 14:25:45 +0000 From: SeongJae Park To: CC: SeongJae Park , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Subject: [RFC v14 3/7] mm/damon/schemes: Implement a debugfs interface Date: Tue, 4 Aug 2020 16:24:26 +0200 Message-ID: <20200804142430.15384-4-sjpark@amazon.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200804142430.15384-1-sjpark@amazon.com> References: <20200804142430.15384-1-sjpark@amazon.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.43.161.203] X-ClientProxiedBy: EX13D17UWC004.ant.amazon.com (10.43.162.195) To EX13D31EUA001.ant.amazon.com (10.43.165.15) X-Rspamd-Queue-Id: 32C0828A26E X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam02 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: From: SeongJae Park This commit implements a debugfs interface for the data access monitoring oriented memory management schemes. It is supposed to be used by administrators and/or privileged user space programs. Users can read and update the rules using ``/damon/schemes`` file. The format is:: Signed-off-by: SeongJae Park --- mm/damon.c | 187 ++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 185 insertions(+), 2 deletions(-) diff --git a/mm/damon.c b/mm/damon.c index e402717a2c0e..d6b4181c5d70 100644 --- a/mm/damon.c +++ b/mm/damon.c @@ -194,6 +194,29 @@ static void damon_destroy_target(struct damon_target *t) damon_free_target(t); } +static struct damos *damon_new_scheme( + unsigned long min_sz_region, unsigned long max_sz_region, + unsigned int min_nr_accesses, unsigned int max_nr_accesses, + unsigned int min_age_region, unsigned int max_age_region, + enum damos_action action) +{ + struct damos *scheme; + + scheme = kmalloc(sizeof(*scheme), GFP_KERNEL); + if (!scheme) + return NULL; + scheme->min_sz_region = min_sz_region; + scheme->max_sz_region = max_sz_region; + scheme->min_nr_accesses = min_nr_accesses; + scheme->max_nr_accesses = max_nr_accesses; + scheme->min_age_region = min_age_region; + scheme->max_age_region = max_age_region; + scheme->action = action; + INIT_LIST_HEAD(&scheme->list); + + return scheme; +} + static void damon_add_scheme(struct damon_ctx *ctx, struct damos *s) { list_add_tail(&s->list, &ctx->schemes_list); @@ -1540,6 +1563,160 @@ static ssize_t debugfs_monitor_on_write(struct file *file, return ret; } +static ssize_t sprint_schemes(struct damon_ctx *c, char *buf, ssize_t len) +{ + struct damos *s; + int written = 0; + int rc; + + damon_for_each_scheme(s, c) { + rc = snprintf(&buf[written], len - written, + "%lu %lu %u %u %u %u %d\n", + s->min_sz_region, s->max_sz_region, + s->min_nr_accesses, s->max_nr_accesses, + s->min_age_region, s->max_age_region, + s->action); + if (!rc) + return -ENOMEM; + + written += rc; + } + return written; +} + +static ssize_t debugfs_schemes_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + struct damon_ctx *ctx = &damon_user_ctx; + char *kbuf; + ssize_t len; + + kbuf = kmalloc(count, GFP_KERNEL); + if (!kbuf) + return -ENOMEM; + + mutex_lock(&ctx->kdamond_lock); + len = sprint_schemes(ctx, kbuf, count); + mutex_unlock(&ctx->kdamond_lock); + if (len < 0) + goto out; + len = simple_read_from_buffer(buf, count, ppos, kbuf, len); + +out: + kfree(kbuf); + return len; +} + +static void free_schemes_arr(struct damos **schemes, ssize_t nr_schemes) +{ + ssize_t i; + + for (i = 0; i < nr_schemes; i++) + kfree(schemes[i]); + kfree(schemes); +} + +static bool damos_action_valid(int action) +{ + switch (action) { + case DAMOS_WILLNEED: + case DAMOS_COLD: + case DAMOS_PAGEOUT: + case DAMOS_HUGEPAGE: + case DAMOS_NOHUGEPAGE: + case DAMOS_STAT: + return true; + default: + return false; + } +} + +/* + * Converts a string into an array of struct damos pointers + * + * Returns an array of struct damos pointers that converted if the conversion + * success, or NULL otherwise. + */ +static struct damos **str_to_schemes(const char *str, ssize_t len, + ssize_t *nr_schemes) +{ + struct damos *scheme, **schemes; + const int max_nr_schemes = 256; + int pos = 0, parsed, ret; + unsigned long min_sz, max_sz; + unsigned int min_nr_a, max_nr_a, min_age, max_age; + unsigned int action; + + schemes = kmalloc_array(max_nr_schemes, sizeof(scheme), + GFP_KERNEL); + if (!schemes) + return NULL; + + *nr_schemes = 0; + while (pos < len && *nr_schemes < max_nr_schemes) { + ret = sscanf(&str[pos], "%lu %lu %u %u %u %u %u%n", + &min_sz, &max_sz, &min_nr_a, &max_nr_a, + &min_age, &max_age, &action, &parsed); + if (ret != 7) + break; + if (!damos_action_valid(action)) { + pr_err("wrong action %d\n", action); + goto fail; + } + + pos += parsed; + scheme = damon_new_scheme(min_sz, max_sz, min_nr_a, max_nr_a, + min_age, max_age, action); + if (!scheme) + goto fail; + + schemes[*nr_schemes] = scheme; + *nr_schemes += 1; + } + return schemes; +fail: + free_schemes_arr(schemes, *nr_schemes); + return NULL; +} + +static ssize_t debugfs_schemes_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct damon_ctx *ctx = &damon_user_ctx; + char *kbuf; + struct damos **schemes; + ssize_t nr_schemes = 0, ret = count; + int err; + + kbuf = user_input_str(buf, count, ppos); + if (IS_ERR(kbuf)) + return PTR_ERR(kbuf); + + schemes = str_to_schemes(kbuf, ret, &nr_schemes); + if (!schemes) { + ret = -EINVAL; + goto out; + } + + mutex_lock(&ctx->kdamond_lock); + if (ctx->kdamond) { + ret = -EBUSY; + goto unlock_out; + } + + err = damon_set_schemes(ctx, schemes, nr_schemes); + if (err) + ret = err; + else + nr_schemes = 0; +unlock_out: + mutex_unlock(&ctx->kdamond_lock); + free_schemes_arr(schemes, nr_schemes); +out: + kfree(kbuf); + return ret; +} + #define targetid_is_pid(ctx) \ (ctx->target_valid == kdamond_vm_target_valid) @@ -1808,6 +1985,12 @@ static const struct file_operations target_ids_fops = { .write = debugfs_target_ids_write, }; +static const struct file_operations schemes_fops = { + .owner = THIS_MODULE, + .read = debugfs_schemes_read, + .write = debugfs_schemes_write, +}; + static const struct file_operations record_fops = { .owner = THIS_MODULE, .read = debugfs_record_read, @@ -1824,10 +2007,10 @@ static struct dentry *debugfs_root; static int __init damon_debugfs_init(void) { - const char * const file_names[] = {"attrs", "record", + const char * const file_names[] = {"attrs", "record", "schemes", "target_ids", "monitor_on"}; const struct file_operations *fops[] = {&attrs_fops, &record_fops, - &target_ids_fops, &monitor_on_fops}; + &schemes_fops, &target_ids_fops, &monitor_on_fops}; int i; debugfs_root = debugfs_create_dir("damon", NULL); -- 2.17.1