From patchwork Tue Oct 17 23:21:50 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nhat Pham X-Patchwork-Id: 734807 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 8692DCDB485 for ; Tue, 17 Oct 2023 23:21:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344295AbjJQXV6 (ORCPT ); Tue, 17 Oct 2023 19:21:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50460 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344285AbjJQXV5 (ORCPT ); Tue, 17 Oct 2023 19:21:57 -0400 Received: from mail-pg1-x535.google.com (mail-pg1-x535.google.com [IPv6:2607:f8b0:4864:20::535]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4F3E4F1; Tue, 17 Oct 2023 16:21:56 -0700 (PDT) Received: by mail-pg1-x535.google.com with SMTP id 41be03b00d2f7-565334377d0so4666227a12.2; Tue, 17 Oct 2023 16:21:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1697584916; x=1698189716; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=Z7v4RebQyJpdc4sQlri0EPJCRWGhgONmwRgz8BMi8es=; b=FJjUrDVNM245FBw75PZq6BIDq4hDWljDViMTS48XAb4zWxhQ9/EfhBzRsXfegH7Zu9 zaISAdljETrWRwxggYurxfCsd05MpK1PAu/Zw/TgNqr0B1DVHfMeTbF+6mvgQqfIOOvy SXeSOYvTtZPzmlierwpu+LlwWNC2vzBZpU/BYTcpE7bSejjB3TD2IZg4K7bqaj2Og1Go sVqO1xtm1oOC6o5DHv/qaLgIvB+V9Dghs56iW8pggg3uR0nUjA0d6/G4JLzv91X6BtLZ W8XipcmBeFmjJOFpCynkvcbjTKh/1PdFQq61+eJtvYc/g6txSZpSOp8p5Fyhpwj+qA8i 26nw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697584916; x=1698189716; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Z7v4RebQyJpdc4sQlri0EPJCRWGhgONmwRgz8BMi8es=; b=BE0hdc4f7iCzhJ1gYXxyaFHr7g7p6t9b7dvD+YxoF07hZwd+sjzokoZtRov9T7/T2t KsvchtWC/m0sWN737G3gj0jmFyWqpZAHiLqDatbIC9OOGcVMpy+lJMxfiw1Z1LRUxJBr C/LSBTknq2r/kjq3kCXi0UyUyQS2C3jA4JbwPsmt0YLRuXzrXPINWGqIV4czKiqKzqhC XcCzYJl3b/cDf/FAOWUav87ms6qN7N5TVwz8dMJWnKbtSS8QJdsRryunGcMIrQzU+eQS SZvpX5G6IEQ7ETrAOMIw9khn7BiKDuYTdddsa+ScM1MNPYgcxxfd0hm4jCsLblfJycK4 Fmzg== X-Gm-Message-State: AOJu0YyjDcNUr9x8Mrnoc1JYw6YuOK9muVMcTzyboN4u+CzMh7yXNOW8 TVhwzQG3yT+TYA/gDuQqDeU= X-Google-Smtp-Source: AGHT+IEfthOH1/vbuwx8GBxLp7AV5HAOVBnZLimkJePzXVxapwVFQUAgYitw91LLn8qQzfjU7hhxjw== X-Received: by 2002:a05:6a20:938b:b0:17a:284:de50 with SMTP id x11-20020a056a20938b00b0017a0284de50mr4589053pzh.6.1697584915727; Tue, 17 Oct 2023 16:21:55 -0700 (PDT) Received: from localhost (fwdproxy-prn-008.fbsv.net. [2a03:2880:ff:8::face:b00c]) by smtp.gmail.com with ESMTPSA id e7-20020a170902b78700b001c735421215sm2116251pls.216.2023.10.17.16.21.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Oct 2023 16:21:55 -0700 (PDT) From: Nhat Pham To: akpm@linux-foundation.org Cc: hannes@cmpxchg.org, cerasuolodomenico@gmail.com, yosryahmed@google.com, sjenning@redhat.com, ddstreet@ieee.org, vitaly.wool@konsulko.com, mhocko@kernel.org, roman.gushchin@linux.dev, shakeelb@google.com, muchun.song@linux.dev, linux-mm@kvack.org, kernel-team@meta.com, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, shuah@kernel.org Subject: [PATCH v3 3/5] mm: memcg: add per-memcg zswap writeback stat Date: Tue, 17 Oct 2023 16:21:50 -0700 Message-Id: <20231017232152.2605440-4-nphamcs@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231017232152.2605440-1-nphamcs@gmail.com> References: <20231017232152.2605440-1-nphamcs@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org From: Domenico Cerasuolo Since zswap now writes back pages from memcg-specific LRUs, we now need a new stat to show writebacks count for each memcg. Suggested-by: Nhat Pham Signed-off-by: Domenico Cerasuolo Signed-off-by: Nhat Pham --- include/linux/memcontrol.h | 2 ++ mm/memcontrol.c | 15 +++++++++++++++ mm/zswap.c | 3 +++ 3 files changed, 20 insertions(+) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 3de10fabea0f..7868b1e00bf5 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -38,6 +38,7 @@ enum memcg_stat_item { MEMCG_KMEM, MEMCG_ZSWAP_B, MEMCG_ZSWAPPED, + MEMCG_ZSWAP_WB, MEMCG_NR_STAT, }; @@ -1884,6 +1885,7 @@ static inline void count_objcg_event(struct obj_cgroup *objcg, bool obj_cgroup_may_zswap(struct obj_cgroup *objcg); void obj_cgroup_charge_zswap(struct obj_cgroup *objcg, size_t size); void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg, size_t size); +void obj_cgroup_report_zswap_wb(struct obj_cgroup *objcg); #else static inline bool obj_cgroup_may_zswap(struct obj_cgroup *objcg) { diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 1bde67b29287..a9118871e5a6 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1505,6 +1505,7 @@ static const struct memory_stat memory_stats[] = { #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) { "zswap", MEMCG_ZSWAP_B }, { "zswapped", MEMCG_ZSWAPPED }, + { "zswap_wb", MEMCG_ZSWAP_WB }, #endif { "file_mapped", NR_FILE_MAPPED }, { "file_dirty", NR_FILE_DIRTY }, @@ -1541,6 +1542,7 @@ static int memcg_page_state_unit(int item) switch (item) { case MEMCG_PERCPU_B: case MEMCG_ZSWAP_B: + case MEMCG_ZSWAP_WB: case NR_SLAB_RECLAIMABLE_B: case NR_SLAB_UNRECLAIMABLE_B: case WORKINGSET_REFAULT_ANON: @@ -7861,6 +7863,19 @@ void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg, size_t size) rcu_read_unlock(); } +void obj_cgroup_report_zswap_wb(struct obj_cgroup *objcg) +{ + struct mem_cgroup *memcg; + + if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) + return; + + rcu_read_lock(); + memcg = obj_cgroup_memcg(objcg); + mod_memcg_state(memcg, MEMCG_ZSWAP_WB, 1); + rcu_read_unlock(); +} + static u64 zswap_current_read(struct cgroup_subsys_state *css, struct cftype *cft) { diff --git a/mm/zswap.c b/mm/zswap.c index d2989ad11814..15485427e3fa 100644 --- a/mm/zswap.c +++ b/mm/zswap.c @@ -704,6 +704,9 @@ static enum lru_status shrink_memcg_cb(struct list_head *item, struct list_lru_o } zswap_written_back_pages++; + if (entry->objcg) + obj_cgroup_report_zswap_wb(entry->objcg); + /* * Writeback started successfully, the page now belongs to the * swapcache. Drop the entry from zswap - unless invalidate already From patchwork Tue Oct 17 23:21:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nhat Pham X-Patchwork-Id: 734806 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 84074CDB482 for ; Tue, 17 Oct 2023 23:22:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344333AbjJQXWB (ORCPT ); Tue, 17 Oct 2023 19:22:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50488 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344300AbjJQXV6 (ORCPT ); Tue, 17 Oct 2023 19:21:58 -0400 Received: from mail-pg1-x52f.google.com (mail-pg1-x52f.google.com [IPv6:2607:f8b0:4864:20::52f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 29FD492; Tue, 17 Oct 2023 16:21:57 -0700 (PDT) Received: by mail-pg1-x52f.google.com with SMTP id 41be03b00d2f7-577e62e2adfso4026563a12.2; Tue, 17 Oct 2023 16:21:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1697584916; x=1698189716; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=l1cHnelUz7JpCw4ya3vv+qgP9pRjbzsLh3QaMob4Kno=; b=bc2Xv+yC6w8vZfRQxkt5/aUH2uyTB32/sDUnY/grhMoJx5YGkQmWQYB23Z7u0IJDZa DPZ/lkY+m2bv0LglAXM1J0oQrfWuAKn5/T+OvBtR62UwGy9fS/fznUWDicQGKtlm/dno XeLJExaFHd/Ha+DVn+lW+vVLly5RRxqjw6uXnKLOk6Z/05trKJLwTqyKVqNvH0T7BAy/ 52Uplxa3q7UxWjsromTdoG32K0EzjpZJRJ3E4/9Bk5xZFNvLN9UFBXlHX6WL/m/o5rQY gLNL9b1Pagk+n2kLu52X86eLCD/wqEfDzkuv7brfcZFv0HSoMl4wJi/4CDCvt1p1xxFl V/gA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697584916; x=1698189716; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=l1cHnelUz7JpCw4ya3vv+qgP9pRjbzsLh3QaMob4Kno=; b=BzT748mXMUsS5UX2HXR08KPS3NME2nxPJ6FbKkkTS6vV+PeoE8JPRRGDHzr8C8qi6c 8yY8RyDiKHpOenMa76NlT40MUoFYKTuE7DAnGPDQBehWzvkQ1GiIhlkUm9uiQ40CprnZ 0ayH1GaSUK4KsfBOTc9xradpxIbQCOHLm1VUvZ3fCgyTPddDW2kAUdt9IlNFIXIXwJ+p s1O6D69zPeH/oBD/UlOzZsL4NIpDOehpPlYq6/efL5UMaCBDSx1MZJPoRZx23d6zlePF WooTcmE8pcAEMxcNbzIWSuMjDJ2t+PRGXI6Pl0r53GQlaRrl+eBM3MdZG14KQRf+zayE TPzw== X-Gm-Message-State: AOJu0YzfLEEr2ixQPW2Gk69qkGoRIi81JLxFLcVYN83CUkK3nk1T8J4s H4Scnv8UX+9CZW2wEINs0tQ= X-Google-Smtp-Source: AGHT+IFesVzJtwp9D46Y7uRYTiIL4vlxo4njVbMDGRffV+cNTLXVfoIhh/9vko3/sNz6DemBDx9n+Q== X-Received: by 2002:a05:6a21:4886:b0:14c:d494:77c3 with SMTP id av6-20020a056a21488600b0014cd49477c3mr3906280pzc.33.1697584916491; Tue, 17 Oct 2023 16:21:56 -0700 (PDT) Received: from localhost (fwdproxy-prn-019.fbsv.net. [2a03:2880:ff:13::face:b00c]) by smtp.gmail.com with ESMTPSA id u12-20020a170902b28c00b001c9bc811d4dsm2111635plr.295.2023.10.17.16.21.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Oct 2023 16:21:56 -0700 (PDT) From: Nhat Pham To: akpm@linux-foundation.org Cc: hannes@cmpxchg.org, cerasuolodomenico@gmail.com, yosryahmed@google.com, sjenning@redhat.com, ddstreet@ieee.org, vitaly.wool@konsulko.com, mhocko@kernel.org, roman.gushchin@linux.dev, shakeelb@google.com, muchun.song@linux.dev, linux-mm@kvack.org, kernel-team@meta.com, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, shuah@kernel.org Subject: [PATCH v3 4/5] selftests: cgroup: update per-memcg zswap writeback selftest Date: Tue, 17 Oct 2023 16:21:51 -0700 Message-Id: <20231017232152.2605440-5-nphamcs@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231017232152.2605440-1-nphamcs@gmail.com> References: <20231017232152.2605440-1-nphamcs@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org From: Domenico Cerasuolo The memcg-zswap self test is updated to adjust to the behavior change implemented by commit 87730b165089 ("zswap: make shrinking memcg-aware"), where zswap performs writeback for specific memcg. Signed-off-by: Domenico Cerasuolo Signed-off-by: Nhat Pham Acked-by: Nhat Pham --- tools/testing/selftests/cgroup/test_zswap.c | 74 ++++++++++++++------- 1 file changed, 50 insertions(+), 24 deletions(-) diff --git a/tools/testing/selftests/cgroup/test_zswap.c b/tools/testing/selftests/cgroup/test_zswap.c index 49def87a909b..11271fabeffc 100644 --- a/tools/testing/selftests/cgroup/test_zswap.c +++ b/tools/testing/selftests/cgroup/test_zswap.c @@ -50,9 +50,9 @@ static int get_zswap_stored_pages(size_t *value) return read_int("/sys/kernel/debug/zswap/stored_pages", value); } -static int get_zswap_written_back_pages(size_t *value) +static int get_cg_wb_count(const char *cg) { - return read_int("/sys/kernel/debug/zswap/written_back_pages", value); + return cg_read_key_long(cg, "memory.stat", "zswap_wb"); } static int allocate_bytes(const char *cgroup, void *arg) @@ -68,45 +68,71 @@ static int allocate_bytes(const char *cgroup, void *arg) return 0; } +static char *setup_test_group_1M(const char *root, const char *name) +{ + char *group_name = cg_name(root, name); + + if (!group_name) + return NULL; + if (cg_create(group_name)) + goto fail; + if (cg_write(group_name, "memory.max", "1M")) { + cg_destroy(group_name); + goto fail; + } + return group_name; +fail: + free(group_name); + return NULL; +} + /* * When trying to store a memcg page in zswap, if the memcg hits its memory - * limit in zswap, writeback should not be triggered. - * - * This was fixed with commit 0bdf0efa180a("zswap: do not shrink if cgroup may - * not zswap"). Needs to be revised when a per memcg writeback mechanism is - * implemented. + * limit in zswap, writeback should affect only the zswapped pages of that + * memcg. */ static int test_no_invasive_cgroup_shrink(const char *root) { - size_t written_back_before, written_back_after; int ret = KSFT_FAIL; - char *test_group; + size_t control_allocation_size = MB(10); + char *control_allocation, *wb_group = NULL, *control_group = NULL; /* Set up */ - test_group = cg_name(root, "no_shrink_test"); - if (!test_group) - goto out; - if (cg_create(test_group)) + wb_group = setup_test_group_1M(root, "per_memcg_wb_test1"); + if (!wb_group) + return KSFT_FAIL; + if (cg_write(wb_group, "memory.zswap.max", "10K")) goto out; - if (cg_write(test_group, "memory.max", "1M")) + control_group = setup_test_group_1M(root, "per_memcg_wb_test2"); + if (!control_group) goto out; - if (cg_write(test_group, "memory.zswap.max", "10K")) + + /* Push some test_group2 memory into zswap */ + if (cg_enter_current(control_group)) goto out; - if (get_zswap_written_back_pages(&written_back_before)) + control_allocation = malloc(control_allocation_size); + for (int i = 0; i < control_allocation_size; i += 4095) + control_allocation[i] = 'a'; + if (cg_read_key_long(control_group, "memory.stat", "zswapped") < 1) goto out; - /* Allocate 10x memory.max to push memory into zswap */ - if (cg_run(test_group, allocate_bytes, (void *)MB(10))) + /* Allocate 10x memory.max to push wb_group memory into zswap and trigger wb */ + if (cg_run(wb_group, allocate_bytes, (void *)MB(10))) goto out; - /* Verify that no writeback happened because of the memcg allocation */ - if (get_zswap_written_back_pages(&written_back_after)) - goto out; - if (written_back_after == written_back_before) + /* Verify that only zswapped memory from gwb_group has been written back */ + if (get_cg_wb_count(wb_group) > 0 && get_cg_wb_count(control_group) == 0) ret = KSFT_PASS; out: - cg_destroy(test_group); - free(test_group); + cg_enter_current(root); + if (control_group) { + cg_destroy(control_group); + free(control_group); + } + cg_destroy(wb_group); + free(wb_group); + if (control_allocation) + free(control_allocation); return ret; }