From patchwork Mon Oct 30 18:20:09 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Haitao Huang X-Patchwork-Id: 13440805 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 E94B9C00142 for ; Mon, 30 Oct 2023 18:20:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233034AbjJ3SUw (ORCPT ); Mon, 30 Oct 2023 14:20:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53306 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232481AbjJ3SUl (ORCPT ); Mon, 30 Oct 2023 14:20:41 -0400 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EE4F9EE; Mon, 30 Oct 2023 11:20:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1698690036; x=1730226036; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=3i2BDE/DBhNogG1Ndm7YAif6roTq2fHz7d8OkLZtLwY=; b=kluN1ngx/Bjc7jVSrCuCkJcNf+TrZS/VPb7hAFayepcciTDMVyCaedUZ trTLC9dxMcKJSdc1aI6/a0mr3m1Ne0Q9D4JD7rEcWwTTJZVHCFbewRL5M 5stacmwTPX4p+agjXbBOzNYMjazBglZg2DRUa7l9/3dmKzjJNuOe21tkl eWWs+MacjEcYywPuG4HELujI7ePtW04+9P2CBDWWFdKeX6qUrc9/X4zr7 Xpg4CpxhUUMm/Z+27o70UvOK9sGjc+ht4fHdnCjzT7DYKtTrXqSeO4ghE Yu6ksSzARVTrDC/zOYrObaSX5ctQpAHH/YHM9sDlzp70Kixt9URYPIt77 Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10879"; a="367479596" X-IronPort-AV: E=Sophos;i="6.03,263,1694761200"; d="scan'208";a="367479596" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Oct 2023 11:20:30 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10879"; a="789529524" X-IronPort-AV: E=Sophos;i="6.03,263,1694761200"; d="scan'208";a="789529524" Received: from b4969161e530.jf.intel.com ([10.165.56.46]) by orsmga008.jf.intel.com with ESMTP; 30 Oct 2023 11:20:29 -0700 From: Haitao Huang To: jarkko@kernel.org, dave.hansen@linux.intel.com, tj@kernel.org, mkoutny@suse.com, linux-kernel@vger.kernel.org, linux-sgx@vger.kernel.org, x86@kernel.org, cgroups@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, hpa@zytor.com, sohil.mehta@intel.com Cc: zhiquan1.li@intel.com, kristen@linux.intel.com, seanjc@google.com, zhanb@microsoft.com, anakrish@microsoft.com, mikko.ylinen@linux.intel.com, yangjie@microsoft.com, Sean Christopherson , Haitao Huang Subject: [PATCH v6 08/12] x86/sgx: Use a list to track to-be-reclaimed pages Date: Mon, 30 Oct 2023 11:20:09 -0700 Message-Id: <20231030182013.40086-9-haitao.huang@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231030182013.40086-1-haitao.huang@linux.intel.com> References: <20231030182013.40086-1-haitao.huang@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org From: Sean Christopherson Change sgx_reclaim_pages() to use a list rather than an array for storing the epc_pages which will be reclaimed. This change is needed to transition to the LRU implementation for EPC cgroup support. When the EPC cgroup is implemented, the reclaiming process will do a pre-order tree walk for the subtree starting from the limit-violating cgroup. When each node is visited, candidate pages are selected from its "reclaimable" LRU list and moved into this temporary list. Passing a list from node to node for temporary storage in this walk is more straightforward than using an array. Signed-off-by: Sean Christopherson Co-developed-by: Kristen Carlson Accardi Signed-off-by: Kristen Carlson Accardi Co-developed-by: Haitao Huang Signed-off-by: Haitao Huang Cc: Sean Christopherson --- V6: - Remove extra list_del_init and style fix (Kai) V4: - Changes needed for patch reordering - Revised commit message V3: - Removed list wrappers --- arch/x86/kernel/cpu/sgx/main.c | 35 +++++++++++++++------------------- 1 file changed, 15 insertions(+), 20 deletions(-) diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c index e27ac73d8843..33bcba313d40 100644 --- a/arch/x86/kernel/cpu/sgx/main.c +++ b/arch/x86/kernel/cpu/sgx/main.c @@ -296,12 +296,11 @@ static void sgx_reclaimer_write(struct sgx_epc_page *epc_page, */ static void sgx_reclaim_pages(void) { - struct sgx_epc_page *chunk[SGX_NR_TO_SCAN]; struct sgx_backing backing[SGX_NR_TO_SCAN]; + struct sgx_epc_page *epc_page, *tmp; struct sgx_encl_page *encl_page; - struct sgx_epc_page *epc_page; pgoff_t page_index; - int cnt = 0; + LIST_HEAD(iso); int ret; int i; @@ -317,7 +316,7 @@ static void sgx_reclaim_pages(void) if (kref_get_unless_zero(&encl_page->encl->refcount) != 0) { sgx_epc_page_set_state(epc_page, SGX_EPC_PAGE_RECLAIM_IN_PROGRESS); - chunk[cnt++] = epc_page; + list_move_tail(&epc_page->list, &iso); } else /* The owner is freeing the page. No need to add the * page back to the list of reclaimable pages. @@ -326,8 +325,11 @@ static void sgx_reclaim_pages(void) } spin_unlock(&sgx_global_lru.lock); - for (i = 0; i < cnt; i++) { - epc_page = chunk[i]; + if (list_empty(&iso)) + return; + + i = 0; + list_for_each_entry_safe(epc_page, tmp, &iso, list) { encl_page = epc_page->owner; if (!sgx_reclaimer_age(epc_page)) @@ -342,6 +344,7 @@ static void sgx_reclaim_pages(void) goto skip; } + i++; encl_page->desc |= SGX_ENCL_PAGE_BEING_RECLAIMED; mutex_unlock(&encl_page->encl->lock); continue; @@ -349,27 +352,19 @@ static void sgx_reclaim_pages(void) skip: spin_lock(&sgx_global_lru.lock); sgx_epc_page_set_state(epc_page, SGX_EPC_PAGE_RECLAIMABLE); - list_add_tail(&epc_page->list, &sgx_global_lru.reclaimable); + list_move_tail(&epc_page->list, &sgx_global_lru.reclaimable); spin_unlock(&sgx_global_lru.lock); kref_put(&encl_page->encl->refcount, sgx_encl_release); - - chunk[i] = NULL; - } - - for (i = 0; i < cnt; i++) { - epc_page = chunk[i]; - if (epc_page) - sgx_reclaimer_block(epc_page); } - for (i = 0; i < cnt; i++) { - epc_page = chunk[i]; - if (!epc_page) - continue; + list_for_each_entry(epc_page, &iso, list) + sgx_reclaimer_block(epc_page); + i = 0; + list_for_each_entry_safe(epc_page, tmp, &iso, list) { encl_page = epc_page->owner; - sgx_reclaimer_write(epc_page, &backing[i]); + sgx_reclaimer_write(epc_page, &backing[i++]); kref_put(&encl_page->encl->refcount, sgx_encl_release); sgx_epc_page_reset_state(epc_page);