From patchwork Mon Apr 6 13:09:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: SeongJae Park X-Patchwork-Id: 11475519 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7BB9F913 for ; Mon, 6 Apr 2020 13:12:08 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 3B3C022450 for ; Mon, 6 Apr 2020 13:12:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b="e3P+h0eV" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3B3C022450 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 7BEED8E001A; Mon, 6 Apr 2020 09:12:07 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 76FC18E000D; Mon, 6 Apr 2020 09:12:07 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 686F68E001A; Mon, 6 Apr 2020 09:12:07 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0138.hostedemail.com [216.40.44.138]) by kanga.kvack.org (Postfix) with ESMTP id 4F4818E000D for ; Mon, 6 Apr 2020 09:12:07 -0400 (EDT) Received: from smtpin03.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 078828016617 for ; Mon, 6 Apr 2020 13:12:07 +0000 (UTC) X-FDA: 76677468294.03.sugar85_69be1c915044c X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,prvs=358a57b7c=sjpark@amazon.com,,RULES_HIT:2539:30003:30034:30054:30064:30067,0,RBL:52.95.48.154:@amazon.com:.lbl8.mailshell.net-62.18.0.100 64.10.201.10,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:25,LUA_SUMMARY:none X-HE-Tag: sugar85_69be1c915044c X-Filterd-Recvd-Size: 10288 Received: from smtp-fw-6001.amazon.com (smtp-fw-6001.amazon.com [52.95.48.154]) by imf08.hostedemail.com (Postfix) with ESMTP for ; Mon, 6 Apr 2020 13:12:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1586178727; x=1617714727; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version; bh=CqS6Kp9m4WsWWHm9t6xWtyCku5EXY5lKLHe479UF6xU=; b=e3P+h0eVJ5a3RZ7S2Q0PjVLNcmDFuDFSGuWht2nZK1w0pqCkYGB6rW7/ InZNgRRKdImcgoI6Vefrjx14E6c0zfFTFjq27tbf6n3soygvrAZMKe6fM IlD/Ig9k0boZ1UzQodjK4wKSM0jgCidLYikrucM0TpK1/ek1WB+Ybsj3m g=; IronPort-SDR: PE87CwuladFlu1rsz24L2jyGH6CNjItnuTTbk87QNV1RfI4beoo2+tDa9HQ2uOwAOmkci4sjpZ xZlJtmwG5h6g== X-IronPort-AV: E=Sophos;i="5.72,351,1580774400"; d="scan'208";a="25728124" Received: from iad12-co-svc-p1-lb1-vlan3.amazon.com (HELO email-inbound-relay-2a-119b4f96.us-west-2.amazon.com) ([10.43.8.6]) by smtp-border-fw-out-6001.iad6.amazon.com with ESMTP; 06 Apr 2020 13:12:03 +0000 Received: from EX13MTAUEA002.ant.amazon.com (pdx4-ws-svc-p6-lb7-vlan2.pdx.amazon.com [10.170.41.162]) by email-inbound-relay-2a-119b4f96.us-west-2.amazon.com (Postfix) with ESMTPS id 192531A021A; Mon, 6 Apr 2020 13:11:59 +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; Mon, 6 Apr 2020 13:11:59 +0000 Received: from u886c93fd17d25d.ant.amazon.com (10.43.160.65) by EX13D31EUA001.ant.amazon.com (10.43.165.15) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Mon, 6 Apr 2020 13:11:45 +0000 From: SeongJae Park To: CC: SeongJae Park , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Subject: [PATCH v8 03/15] mm: Introduce Data Access MONitor (DAMON) Date: Mon, 6 Apr 2020 15:09:26 +0200 Message-ID: <20200406130938.14066-4-sjpark@amazon.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200406130938.14066-1-sjpark@amazon.com> References: <20200406130938.14066-1-sjpark@amazon.com> MIME-Version: 1.0 X-Originating-IP: [10.43.160.65] X-ClientProxiedBy: EX13D11UWB003.ant.amazon.com (10.43.161.206) To EX13D31EUA001.ant.amazon.com (10.43.165.15) 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 introduces a kernel module named DAMON. Note that this commit is implementing only the stub for the module load/unload, basic data structures, and simple manipulation functions of the structures to keep the size of commit small. The core mechanisms of DAMON will be implemented one by one by following commits. Signed-off-by: SeongJae Park --- include/linux/damon.h | 38 +++++++++ mm/Kconfig | 11 +++ mm/Makefile | 1 + mm/damon.c | 189 ++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 239 insertions(+) create mode 100644 include/linux/damon.h create mode 100644 mm/damon.c diff --git a/include/linux/damon.h b/include/linux/damon.h new file mode 100644 index 000000000000..7117bb7e7544 --- /dev/null +++ b/include/linux/damon.h @@ -0,0 +1,38 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * DAMON api + * + * Copyright 2019 Amazon.com, Inc. or its affiliates. All rights reserved. + * + * Author: SeongJae Park + */ + +#ifndef _DAMON_H_ +#define _DAMON_H_ + +#include +#include + +/* Represents a monitoring target region on the virtual address space */ +struct damon_region { + unsigned long vm_start; + unsigned long vm_end; + unsigned long sampling_addr; + unsigned int nr_accesses; + struct list_head list; +}; + +/* Represents a monitoring target task */ +struct damon_task { + unsigned long pid; + struct list_head regions_list; + struct list_head list; +}; + +struct damon_ctx { + struct rnd_state rndseed; + + struct list_head tasks_list; /* 'damon_task' objects */ +}; + +#endif diff --git a/mm/Kconfig b/mm/Kconfig index ab80933be65f..79da00d15604 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -739,4 +739,15 @@ config ARCH_HAS_HUGEPD config MAPPING_DIRTY_HELPERS bool +config DAMON + tristate "Data Access Monitor" + depends on MMU + help + Provides data access monitoring. + + DAMON is a kernel module that allows users to monitor the actual + memory access pattern of specific user-space processes. It aims to + be 1) accurate enough to be useful for performance-centric domains, + and 2) sufficiently light-weight so that it can be applied online. + endmenu diff --git a/mm/Makefile b/mm/Makefile index 272e66039e70..5346314edee6 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -110,3 +110,4 @@ obj-$(CONFIG_HMM_MIRROR) += hmm.o obj-$(CONFIG_MEMFD_CREATE) += memfd.o obj-$(CONFIG_MAPPING_DIRTY_HELPERS) += mapping_dirty_helpers.o obj-$(CONFIG_PTDUMP_CORE) += ptdump.o +obj-$(CONFIG_DAMON) += damon.o diff --git a/mm/damon.c b/mm/damon.c new file mode 100644 index 000000000000..d7e6226ab7f1 --- /dev/null +++ b/mm/damon.c @@ -0,0 +1,189 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Data Access Monitor + * + * Copyright 2019 Amazon.com, Inc. or its affiliates. All rights reserved. + * + * Author: SeongJae Park + */ + +#define pr_fmt(fmt) "damon: " fmt + +#include +#include +#include +#include + +#define damon_get_task_struct(t) \ + (get_pid_task(find_vpid(t->pid), PIDTYPE_PID)) + +#define damon_next_region(r) \ + (container_of(r->list.next, struct damon_region, list)) + +#define damon_prev_region(r) \ + (container_of(r->list.prev, struct damon_region, list)) + +#define damon_for_each_region(r, t) \ + list_for_each_entry(r, &t->regions_list, list) + +#define damon_for_each_region_safe(r, next, t) \ + list_for_each_entry_safe(r, next, &t->regions_list, list) + +#define damon_for_each_task(ctx, t) \ + list_for_each_entry(t, &(ctx)->tasks_list, list) + +#define damon_for_each_task_safe(ctx, t, next) \ + list_for_each_entry_safe(t, next, &(ctx)->tasks_list, list) + +/* Get a random number in [l, r) */ +#define damon_rand(ctx, l, r) (l + prandom_u32_state(&ctx->rndseed) % (r - l)) + +/* + * Construct a damon_region struct + * + * Returns the pointer to the new struct if success, or NULL otherwise + */ +static struct damon_region *damon_new_region(struct damon_ctx *ctx, + unsigned long vm_start, unsigned long vm_end) +{ + struct damon_region *region; + + region = kmalloc(sizeof(*region), GFP_KERNEL); + if (!region) + return NULL; + + region->vm_start = vm_start; + region->vm_end = vm_end; + region->nr_accesses = 0; + region->sampling_addr = damon_rand(ctx, vm_start, vm_end); + INIT_LIST_HEAD(®ion->list); + + return region; +} + +/* + * Add a region between two other regions + */ +static inline void damon_insert_region(struct damon_region *r, + struct damon_region *prev, struct damon_region *next) +{ + __list_add(&r->list, &prev->list, &next->list); +} + +static void damon_add_region(struct damon_region *r, struct damon_task *t) +{ + list_add_tail(&r->list, &t->regions_list); +} + +static void damon_del_region(struct damon_region *r) +{ + list_del(&r->list); +} + +static void damon_free_region(struct damon_region *r) +{ + kfree(r); +} + +static void damon_destroy_region(struct damon_region *r) +{ + damon_del_region(r); + damon_free_region(r); +} + +/* + * Construct a damon_task struct + * + * Returns the pointer to the new struct if success, or NULL otherwise + */ +static struct damon_task *damon_new_task(unsigned long pid) +{ + struct damon_task *t; + + t = kmalloc(sizeof(*t), GFP_KERNEL); + if (!t) + return NULL; + + t->pid = pid; + INIT_LIST_HEAD(&t->regions_list); + + return t; +} + +/* Returns n-th damon_region of the given task */ +struct damon_region *damon_nth_region_of(struct damon_task *t, unsigned int n) +{ + struct damon_region *r; + unsigned int i = 0; + + damon_for_each_region(r, t) { + if (i++ == n) + return r; + } + + return NULL; +} + +static void damon_add_task(struct damon_ctx *ctx, struct damon_task *t) +{ + list_add_tail(&t->list, &ctx->tasks_list); +} + +static void damon_del_task(struct damon_task *t) +{ + list_del(&t->list); +} + +static void damon_free_task(struct damon_task *t) +{ + struct damon_region *r, *next; + + damon_for_each_region_safe(r, next, t) + damon_free_region(r); + kfree(t); +} + +static void damon_destroy_task(struct damon_task *t) +{ + damon_del_task(t); + damon_free_task(t); +} + +static unsigned int nr_damon_tasks(struct damon_ctx *ctx) +{ + struct damon_task *t; + unsigned int nr_tasks = 0; + + damon_for_each_task(ctx, t) + nr_tasks++; + + return nr_tasks; +} + +static unsigned int nr_damon_regions(struct damon_task *t) +{ + struct damon_region *r; + unsigned int nr_regions = 0; + + damon_for_each_region(r, t) + nr_regions++; + + return nr_regions; +} + +static int __init damon_init(void) +{ + return 0; +} + +static void __exit damon_exit(void) +{ + return; +} + +module_init(damon_init); +module_exit(damon_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("SeongJae Park "); +MODULE_DESCRIPTION("DAMON: Data Access MONitor");