From patchwork Mon Feb 5 21:06:28 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Haitao Huang X-Patchwork-Id: 13546249 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.12]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 75A02144623; Mon, 5 Feb 2024 21:06:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.12 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707167208; cv=none; b=HleW/Ed9+nnNxOgcxs0g1QHTPpibngUMaqalcu9GgU+aecRIRBzuev/oL2TBa4En5d3ValGWdsdGAckCnnO2dYPcSVV8QrefAhLFfyQxuinS9SBxAVshgebDlhyvyazue/vZkK3wDUn4mj+Al4AG6Mv1N0t9zA1RIIT8niWKZno= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707167208; c=relaxed/simple; bh=ZwhQ8rGrkYGE4Cq6ve+NL1Ph2G7gIbD0pcvXlPmoUGk=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=hWeMbXWm42akiC94f+xvjLDDS4mVmzHk7Yz4sIOKVatiOrwl0whz+1I7IcAuPFhbuBqN5L/jvK4bVqknIhGIX58fjCS1q1s4SEa1qaGN9INr+2zE9YHb4mtfRPAphZ2L3FAKxyvEWUmE2Bm5xeoaE8V+Gz+U9p8nR+qzXRD2PNY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=KTxT9ezv; arc=none smtp.client-ip=198.175.65.12 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="KTxT9ezv" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1707167207; x=1738703207; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=ZwhQ8rGrkYGE4Cq6ve+NL1Ph2G7gIbD0pcvXlPmoUGk=; b=KTxT9ezvpZkqHitPMfWqbTTaF5hgBlYrBjMD89MSZgHAeRLrLr/Gs9xx IZwTOD2fIEm+hdsKl9vZn4abwlB4mPHvCb4L7dVRC8AF2Lx2/fPaU3tg0 nEP2l4ymoKotnPDLlfKH4TwhtfKQTNO6UPvrSDbrJI8A9ebWERSlalaEC r+dyjGBjXPz1/m2iPCtOqf+UDUWmacBXDTcnUnrE2rBZyzttgsqkx9u7/ yCzsD8ksXMWW9nLjAjn0/7+gfuSIv/T2ULSK8Os0IbPVW8E80oxq9iUH8 NVY0uiWp4Ms3JmRirtGx522w91FDoaaTTM53Y8KmNy0FUR8f9dZgF5IOA w==; X-IronPort-AV: E=McAfee;i="6600,9927,10975"; a="11960418" X-IronPort-AV: E=Sophos;i="6.05,245,1701158400"; d="scan'208";a="11960418" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by orvoesa104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Feb 2024 13:06:42 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.05,245,1701158400"; d="scan'208";a="38245622" Received: from b4969161e530.jf.intel.com ([10.165.56.46]) by orviesa001.jf.intel.com with ESMTP; 05 Feb 2024 13:06:40 -0800 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, tim.c.chen@linux.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, chrisyan@microsoft.com Subject: [PATCH v9 05/15] x86/sgx: Add sgx_epc_lru_list to encapsulate LRU list Date: Mon, 5 Feb 2024 13:06:28 -0800 Message-Id: <20240205210638.157741-6-haitao.huang@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240205210638.157741-1-haitao.huang@linux.intel.com> References: <20240205210638.157741-1-haitao.huang@linux.intel.com> Precedence: bulk X-Mailing-List: linux-sgx@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Sean Christopherson Introduce a data structure to wrap the existing reclaimable list and its spinlock. Each cgroup later will have one instance of this structure to track EPC pages allocated for processes associated with the same cgroup. Just like the global SGX reclaimer (ksgxd), an EPC cgroup reclaims pages from the reclaimable list in this structure when its usage reaches near its limit. Use this structure to encapsulate the LRU list and its lock used by the global reclaimer. 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 Reviewed-by: Jarkko Sakkinen --- V6: - removed introduction to unreclaimables in commit message. V4: - Removed unneeded comments for the spinlock and the non-reclaimables. (Kai, Jarkko) - Revised the commit to add introduction comments for unreclaimables and multiple LRU lists.(Kai) - Reordered the patches: delay all changes for unreclaimables to later, and this one becomes the first change in the SGX subsystem. V3: - Removed the helper functions and revised commit messages. --- arch/x86/kernel/cpu/sgx/main.c | 39 +++++++++++++++++----------------- arch/x86/kernel/cpu/sgx/sgx.h | 15 +++++++++++++ 2 files changed, 35 insertions(+), 19 deletions(-) diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c index c32f18b70c73..912959c7ecc9 100644 --- a/arch/x86/kernel/cpu/sgx/main.c +++ b/arch/x86/kernel/cpu/sgx/main.c @@ -28,10 +28,9 @@ static DEFINE_XARRAY(sgx_epc_address_space); /* * These variables are part of the state of the reclaimer, and must be accessed - * with sgx_reclaimer_lock acquired. + * with sgx_global_lru.lock acquired. */ -static LIST_HEAD(sgx_active_page_list); -static DEFINE_SPINLOCK(sgx_reclaimer_lock); +static struct sgx_epc_lru_list sgx_global_lru; static atomic_long_t sgx_nr_free_pages = ATOMIC_LONG_INIT(0); @@ -306,13 +305,13 @@ static void sgx_reclaim_pages(void) int ret; int i; - spin_lock(&sgx_reclaimer_lock); + spin_lock(&sgx_global_lru.lock); for (i = 0; i < SGX_NR_TO_SCAN; i++) { - if (list_empty(&sgx_active_page_list)) + epc_page = list_first_entry_or_null(&sgx_global_lru.reclaimable, + struct sgx_epc_page, list); + if (!epc_page) break; - epc_page = list_first_entry(&sgx_active_page_list, - struct sgx_epc_page, list); list_del_init(&epc_page->list); encl_page = epc_page->owner; @@ -324,7 +323,7 @@ static void sgx_reclaim_pages(void) */ epc_page->flags &= ~SGX_EPC_PAGE_RECLAIMER_TRACKED; } - spin_unlock(&sgx_reclaimer_lock); + spin_unlock(&sgx_global_lru.lock); for (i = 0; i < cnt; i++) { epc_page = chunk[i]; @@ -347,9 +346,9 @@ static void sgx_reclaim_pages(void) continue; skip: - spin_lock(&sgx_reclaimer_lock); - list_add_tail(&epc_page->list, &sgx_active_page_list); - spin_unlock(&sgx_reclaimer_lock); + spin_lock(&sgx_global_lru.lock); + list_add_tail(&epc_page->list, &sgx_global_lru.reclaimable); + spin_unlock(&sgx_global_lru.lock); kref_put(&encl_page->encl->refcount, sgx_encl_release); @@ -380,7 +379,7 @@ static void sgx_reclaim_pages(void) static bool sgx_should_reclaim(unsigned long watermark) { return atomic_long_read(&sgx_nr_free_pages) < watermark && - !list_empty(&sgx_active_page_list); + !list_empty(&sgx_global_lru.reclaimable); } /* @@ -432,6 +431,8 @@ static bool __init sgx_page_reclaimer_init(void) ksgxd_tsk = tsk; + sgx_lru_init(&sgx_global_lru); + return true; } @@ -507,10 +508,10 @@ struct sgx_epc_page *__sgx_alloc_epc_page(void) */ void sgx_mark_page_reclaimable(struct sgx_epc_page *page) { - spin_lock(&sgx_reclaimer_lock); + spin_lock(&sgx_global_lru.lock); page->flags |= SGX_EPC_PAGE_RECLAIMER_TRACKED; - list_add_tail(&page->list, &sgx_active_page_list); - spin_unlock(&sgx_reclaimer_lock); + list_add_tail(&page->list, &sgx_global_lru.reclaimable); + spin_unlock(&sgx_global_lru.lock); } /** @@ -525,18 +526,18 @@ void sgx_mark_page_reclaimable(struct sgx_epc_page *page) */ int sgx_unmark_page_reclaimable(struct sgx_epc_page *page) { - spin_lock(&sgx_reclaimer_lock); + spin_lock(&sgx_global_lru.lock); if (page->flags & SGX_EPC_PAGE_RECLAIMER_TRACKED) { /* The page is being reclaimed. */ if (list_empty(&page->list)) { - spin_unlock(&sgx_reclaimer_lock); + spin_unlock(&sgx_global_lru.lock); return -EBUSY; } list_del(&page->list); page->flags &= ~SGX_EPC_PAGE_RECLAIMER_TRACKED; } - spin_unlock(&sgx_reclaimer_lock); + spin_unlock(&sgx_global_lru.lock); return 0; } @@ -578,7 +579,7 @@ struct sgx_epc_page *sgx_alloc_epc_page(void *owner, bool reclaim) break; } - if (list_empty(&sgx_active_page_list)) { + if (list_empty(&sgx_global_lru.reclaimable)) { page = ERR_PTR(-ENOMEM); break; } diff --git a/arch/x86/kernel/cpu/sgx/sgx.h b/arch/x86/kernel/cpu/sgx/sgx.h index a898d86dead0..0e99e9ae3a67 100644 --- a/arch/x86/kernel/cpu/sgx/sgx.h +++ b/arch/x86/kernel/cpu/sgx/sgx.h @@ -88,6 +88,21 @@ static inline void *sgx_get_epc_virt_addr(struct sgx_epc_page *page) return section->virt_addr + index * PAGE_SIZE; } +/* + * Contains EPC pages tracked by the global reclaimer (ksgxd) or an EPC + * cgroup. + */ +struct sgx_epc_lru_list { + spinlock_t lock; + struct list_head reclaimable; +}; + +static inline void sgx_lru_init(struct sgx_epc_lru_list *lru) +{ + spin_lock_init(&lru->lock); + INIT_LIST_HEAD(&lru->reclaimable); +} + struct sgx_epc_page *__sgx_alloc_epc_page(void); void sgx_free_epc_page(struct sgx_epc_page *page);