From patchwork Thu Sep 22 17:10:46 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kristen Carlson Accardi X-Patchwork-Id: 12985589 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 6A235C54EE9 for ; Thu, 22 Sep 2022 17:12:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231792AbiIVRMF (ORCPT ); Thu, 22 Sep 2022 13:12:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40444 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231982AbiIVRLx (ORCPT ); Thu, 22 Sep 2022 13:11:53 -0400 Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0DCF4100AA4; Thu, 22 Sep 2022 10:11:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1663866708; x=1695402708; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=YYmyfKC3KMAXnaj8uAGWA1KxL3gThquOW2nfx+FoyxM=; b=QB2pUA5r0oWn0mSF4286hqTK36NxZRmicAWUphAmDGHoTlDkESUdczRw B3KhfNXHf0bUC3UHiCyYEDygDvTMGdMmEp8REQ4oX2MlI5+o0LGlYBi/6 WVUJTq/Kn4E53PYMY15hzCy486b73v3mxObds6nfb6+iaamTUiOdWmUmY KpG8Zdi9ZP9JnovkDLU5fKx5R0aA5zatg8caugg/xATJEa8JVn5EUNXkz lNDGkJefxERcNRZah4R6tBE2cZbS9r8v4cEVfVCueHP4Q37/vWaJcyvpU mGSd+LLSMt94XvKAA7NjGtfAiWQ+9ErTXn6nk0EBU0fqRsn0lmeeleCFJ Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10478"; a="299081597" X-IronPort-AV: E=Sophos;i="5.93,337,1654585200"; d="scan'208";a="299081597" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Sep 2022 10:11:47 -0700 X-IronPort-AV: E=Sophos;i="5.93,337,1654585200"; d="scan'208";a="762270115" Received: from sknaidu-mobl1.amr.corp.intel.com (HELO kcaccard-desk.amr.corp.intel.com) ([10.212.165.187]) by fmsmga001-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Sep 2022 10:11:29 -0700 From: Kristen Carlson Accardi To: linux-kernel@vger.kernel.org, linux-sgx@vger.kernel.org, cgroups@vger.kernel.org, Jarkko Sakkinen , Dave Hansen , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H. Peter Anvin" Cc: Kristen Carlson Accardi , Sean Christopherson Subject: [RFC PATCH 09/20] x86/sgx: Allow reclaiming up to 32 pages, but scan 16 by default Date: Thu, 22 Sep 2022 10:10:46 -0700 Message-Id: <20220922171057.1236139-10-kristen@linux.intel.com> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20220922171057.1236139-1-kristen@linux.intel.com> References: <20220922171057.1236139-1-kristen@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org From: Sean Christopherson Modify sgx_reclaim_pages() to take a parameter that specifies the number of pages to scan for reclaiming. Specify a max value of 32, but scan 16 in the usual case. This allows the number of pages sgx_reclaim_pages() scans to be specified by the caller, and adjusted in future patches. Signed-off-by: Sean Christopherson Signed-off-by: Kristen Carlson Accardi Cc: Sean Christopherson --- arch/x86/kernel/cpu/sgx/main.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c index 3c0d33b72896..0010ed1b2e98 100644 --- a/arch/x86/kernel/cpu/sgx/main.c +++ b/arch/x86/kernel/cpu/sgx/main.c @@ -18,6 +18,8 @@ #include "encl.h" #include "encls.h" +#define SGX_MAX_NR_TO_RECLAIM 32 + struct sgx_epc_section sgx_epc_sections[SGX_MAX_EPC_SECTIONS]; static int sgx_nr_epc_sections; static struct task_struct *ksgxd_tsk; @@ -273,7 +275,10 @@ static void sgx_reclaimer_write(struct sgx_epc_page *epc_page, mutex_unlock(&encl->lock); } -/* +/** + * sgx_reclaim_pages() - Reclaim EPC pages from the consumers + * @nr_to_scan: Number of EPC pages to scan for reclaim + * * Take a fixed number of pages from the head of the active page pool and * reclaim them to the enclave's private shmem files. Skip the pages, which have * been accessed since the last scan. Move those pages to the tail of active @@ -286,9 +291,9 @@ static void sgx_reclaimer_write(struct sgx_epc_page *epc_page, * problematic as it would increase the lock contention too much, which would * halt forward progress. */ -static void sgx_reclaim_pages(void) +static void sgx_reclaim_pages(int nr_to_scan) { - struct sgx_backing backing[SGX_NR_TO_SCAN]; + struct sgx_backing backing[SGX_MAX_NR_TO_RECLAIM]; struct sgx_encl_page *encl_page; struct sgx_epc_page *epc_page, *tmp; pgoff_t page_index; @@ -297,7 +302,7 @@ static void sgx_reclaim_pages(void) int i; spin_lock(&sgx_global_lru.lock); - for (i = 0; i < SGX_NR_TO_SCAN; i++) { + for (i = 0; i < nr_to_scan; i++) { if (list_empty(&sgx_global_lru.reclaimable)) break; @@ -327,7 +332,7 @@ static void sgx_reclaim_pages(void) list_for_each_entry_safe(epc_page, tmp, &iso, list) { encl_page = epc_page->owner; - if (!sgx_reclaimer_age(epc_page)) + if (i == SGX_MAX_NR_TO_RECLAIM || !sgx_reclaimer_age(epc_page)) goto skip; page_index = PFN_DOWN(encl_page->desc - encl_page->encl->base); @@ -384,7 +389,7 @@ static bool sgx_should_reclaim(unsigned long watermark) void sgx_reclaim_direct(void) { if (sgx_should_reclaim(SGX_NR_LOW_PAGES)) - sgx_reclaim_pages(); + sgx_reclaim_pages(SGX_NR_TO_SCAN); } static int ksgxd(void *p) @@ -410,7 +415,7 @@ static int ksgxd(void *p) sgx_should_reclaim(SGX_NR_HIGH_PAGES)); if (sgx_should_reclaim(SGX_NR_HIGH_PAGES)) - sgx_reclaim_pages(); + sgx_reclaim_pages(SGX_NR_TO_SCAN); } return 0; @@ -581,7 +586,7 @@ struct sgx_epc_page *sgx_alloc_epc_page(void *owner, bool reclaim) break; } - sgx_reclaim_pages(); + sgx_reclaim_pages(SGX_NR_TO_SCAN); } if (sgx_should_reclaim(SGX_NR_LOW_PAGES))