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=-13.6 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=unavailable 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 A0C82C4727E for ; Wed, 7 Oct 2020 07:15:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 498F9207EA for ; Wed, 7 Oct 2020 07:15:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b="izglYSq4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727711AbgJGHPR (ORCPT ); Wed, 7 Oct 2020 03:15:17 -0400 Received: from smtp-fw-6002.amazon.com ([52.95.49.90]:52470 "EHLO smtp-fw-6002.amazon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727684AbgJGHPR (ORCPT ); Wed, 7 Oct 2020 03:15:17 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1602054916; x=1633590916; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version; bh=OxApDNVBe9qJrgKMXpVHXXem1zXkEyX41XgSrJ5ico4=; b=izglYSq4Ixoe7yY7ZGzN5swP1eOo/D22sXd38EY5B823NCNIMoVFVqcG TsIE7BQf8rdok08kyOMAE9vl3rb+meLkx4NcvWdsrFA4Nx8eJtTEJJ9S2 PkBRoLJPCTqxVbu57Eouxqg+okwCaqB+kOyevV7Qi8X2lg+z8OkQtQhiM U=; X-IronPort-AV: E=Sophos;i="5.77,345,1596499200"; d="scan'208";a="58523428" Received: from iad12-co-svc-p1-lb1-vlan3.amazon.com (HELO email-inbound-relay-1d-74cf8b49.us-east-1.amazon.com) ([10.43.8.6]) by smtp-border-fw-out-6002.iad6.amazon.com with ESMTP; 07 Oct 2020 07:15:15 +0000 Received: from EX13D31EUA004.ant.amazon.com (iad12-ws-svc-p26-lb9-vlan3.iad.amazon.com [10.40.163.38]) by email-inbound-relay-1d-74cf8b49.us-east-1.amazon.com (Postfix) with ESMTPS id CC8FAC09AE; Wed, 7 Oct 2020 07:15:03 +0000 (UTC) Received: from u3f2cd687b01c55.ant.amazon.com (10.43.162.73) by EX13D31EUA004.ant.amazon.com (10.43.165.161) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Wed, 7 Oct 2020 07:14:47 +0000 From: SeongJae Park To: CC: SeongJae Park , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Subject: [RFC v9 01/10] damon/dbgfs: Allow users to set initial monitoring target regions Date: Wed, 7 Oct 2020 09:14:00 +0200 Message-ID: <20201007071409.12174-2-sjpark@amazon.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20201007071409.12174-1-sjpark@amazon.com> References: <20201007071409.12174-1-sjpark@amazon.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.43.162.73] X-ClientProxiedBy: EX13D31UWA003.ant.amazon.com (10.43.160.130) To EX13D31EUA004.ant.amazon.com (10.43.165.161) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: SeongJae Park Some 'damon-dbgfs' users would want to monitor only a part of the entire virtual memory address space. The framework users in the kernel space could use '->init_target_regions' callback or even set the regions inside the context struct as they want, but 'damon-dbgfs' users cannot. For the reason, this commit introduces a new debugfs file, 'init_region'. 'damon-dbgfs' users can specify which initial monitoring target address regions they want by writing special input to the file. The input should describe each region in each line in below form: Note that the regions will be updated to cover entire memory mapped regions after 'regions update interval'. If you want the regions to not be updated after the initial setting, you could set the interval as a very long time, say, a few decades. Signed-off-by: SeongJae Park --- mm/damon/dbgfs.c | 154 ++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 151 insertions(+), 3 deletions(-) diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c index 9390ed9b9304..28076557ea86 100644 --- a/mm/damon/dbgfs.c +++ b/mm/damon/dbgfs.c @@ -523,6 +523,147 @@ static ssize_t dbgfs_target_ids_write(struct file *file, return ret; } +static ssize_t sprint_init_regions(struct damon_ctx *c, char *buf, ssize_t len) +{ + struct damon_target *t; + struct damon_region *r; + int written = 0; + int rc; + + damon_for_each_target(t, c) { + damon_for_each_region(r, t) { + rc = scnprintf(&buf[written], len - written, + "%lu %lu %lu\n", + t->id, r->ar.start, r->ar.end); + if (!rc) + return -ENOMEM; + written += rc; + } + } + return written; +} + +static ssize_t dbgfs_init_regions_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + struct damon_ctx *ctx = file->private_data; + char *kbuf; + ssize_t len; + + kbuf = kmalloc(count, GFP_KERNEL); + if (!kbuf) + return -ENOMEM; + + mutex_lock(&ctx->kdamond_lock); + if (ctx->kdamond) { + mutex_unlock(&ctx->kdamond_lock); + return -EBUSY; + } + + len = sprint_init_regions(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 int add_init_region(struct damon_ctx *c, + unsigned long target_id, struct damon_addr_range *ar) +{ + struct damon_target *t; + struct damon_region *r, *prev; + int rc = -EINVAL; + + if (ar->start >= ar->end) + return -EINVAL; + + damon_for_each_target(t, c) { + if (t->id == target_id) { + r = damon_new_region(ar->start, ar->end); + if (!r) + return -ENOMEM; + damon_add_region(r, t); + if (damon_nr_regions(t) > 1) { + prev = damon_prev_region(r); + if (prev->ar.end > r->ar.start) { + damon_destroy_region(r); + return -EINVAL; + } + } + rc = 0; + } + } + return rc; +} + +static int set_init_regions(struct damon_ctx *c, const char *str, ssize_t len) +{ + struct damon_target *t; + struct damon_region *r, *next; + int pos = 0, parsed, ret; + unsigned long target_id; + struct damon_addr_range ar; + int err; + + damon_for_each_target(t, c) { + damon_for_each_region_safe(r, next, t) + damon_destroy_region(r); + } + + while (pos < len) { + ret = sscanf(&str[pos], "%lu %lu %lu%n", + &target_id, &ar.start, &ar.end, &parsed); + if (ret != 3) + break; + err = add_init_region(c, target_id, &ar); + if (err) + goto fail; + pos += parsed; + } + + return 0; + +fail: + damon_for_each_target(t, c) { + damon_for_each_region_safe(r, next, t) + damon_destroy_region(r); + } + return err; +} + +static ssize_t dbgfs_init_regions_write(struct file *file, + const char __user *buf, size_t count, + loff_t *ppos) +{ + struct damon_ctx *ctx = file->private_data; + char *kbuf; + ssize_t ret = count; + int err; + + kbuf = user_input_str(buf, count, ppos); + if (IS_ERR(kbuf)) + return PTR_ERR(kbuf); + + mutex_lock(&ctx->kdamond_lock); + if (ctx->kdamond) { + ret = -EBUSY; + goto unlock_out; + } + + err = set_init_regions(ctx, kbuf, ret); + if (err) + ret = err; + +unlock_out: + mutex_unlock(&ctx->kdamond_lock); + kfree(kbuf); + return ret; +} + static ssize_t dbgfs_kdamond_pid_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) { @@ -584,6 +725,13 @@ static const struct file_operations target_ids_fops = { .write = dbgfs_target_ids_write, }; +static const struct file_operations init_regions_fops = { + .owner = THIS_MODULE, + .open = damon_dbgfs_open, + .read = dbgfs_init_regions_read, + .write = dbgfs_init_regions_write, +}; + static const struct file_operations kdamond_pid_fops = { .owner = THIS_MODULE, .open = damon_dbgfs_open, @@ -593,9 +741,9 @@ static const struct file_operations kdamond_pid_fops = { static int dbgfs_fill_ctx_dir(struct dentry *dir, struct damon_ctx *ctx) { const char * const file_names[] = {"attrs", "record", "schemes", - "target_ids", "kdamond_pid"}; - const struct file_operations *fops[] = {&attrs_fops, - &record_fops, &schemes_fops, &target_ids_fops, + "target_ids", "init_regions", "kdamond_pid"}; + const struct file_operations *fops[] = {&attrs_fops, &record_fops, + &schemes_fops, &target_ids_fops, &init_regions_fops, &kdamond_pid_fops}; int i; -- 2.17.1