From mboxrd@z Thu Jan 1 00:00:00 1970 From: Haitao Huang Subject: [PATCH v4 14/18] x86/sgx: Add helper to grab pages from an arbitrary EPC LRU Date: Tue, 12 Sep 2023 21:06:31 -0700 Message-ID: <20230913040635.28815-15-haitao.huang@linux.intel.com> References: <20230913040635.28815-1-haitao.huang@linux.intel.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1694578139; x=1726114139; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=9K4lkxszdYXWqW66P8rfWQzfOVoQfKmanJIZjiiAlD8=; b=n3slb7FV1nVwrPmIB7SwFkiVOXFK299FzlOpJiV74NHNGS9x1/CuNfUw J06KrtBPtz5zvVHwI2snaotmVetVh8EJAwQ5NpskGKUhpzKK0Ehzkshbw NKx7uPfzn0u6lz6OLWEihoutjcTXEjlRm/ONrVkvweSFXoUcpo10iIozP CtXn7rTPfkKbWVa9FAQfMcHQ0tbfiosEgYKP13nPReix9aJ88Z+G1JZJW JcI2MaPcwRz5gPBDOY7wvvriOw3/WiU4dy/h6jheJbxVY4ZhjGZrjhd3w cEsiUtNKtodW8a3hqbzObh9Lkvic2UxpBOrUQ7pOZDao+MiGBPTKiGQKc g==; In-Reply-To: <20230913040635.28815-1-haitao.huang-VuQAYsv1563Yd54FQh9/CA@public.gmane.org> List-ID: Content-Type: text/plain; charset="us-ascii" To: jarkko-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, dave.hansen-VuQAYsv1563Yd54FQh9/CA@public.gmane.org, tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-sgx-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org, mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, bp-Gina5bIWoIWzQB+pC5nmwQ@public.gmane.org, hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org, sohil.mehta-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org Cc: zhiquan1.li-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, kristen-VuQAYsv1563Yd54FQh9/CA@public.gmane.org, seanjc-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, zhanb-0li6OtcxBFHby3iVrkZq2A@public.gmane.org, anakrish-0li6OtcxBFHby3iVrkZq2A@public.gmane.org, mikko.ylinen-VuQAYsv1563Yd54FQh9/CA@public.gmane.org, yangjie-0li6OtcxBFHby3iVrkZq2A@public.gmane.org From: Sean Christopherson Move the isolation loop into a helper, sgx_isolate_pages(), in preparation for existence of multiple LRUs. Expose the helper to other SGX code so that it can be called from the EPC cgroup code, e.g., to isolate pages from a single cgroup LRU. Exposing the isolation loop allows the cgroup iteration logic to be wholly encapsulated within the cgroup code. Signed-off-by: Sean Christopherson Signed-off-by: Kristen Carlson Accardi Signed-off-by: Haitao Huang Cc: Sean Christopherson --- V4: - No changes other than reordering the patches --- arch/x86/kernel/cpu/sgx/main.c | 57 +++++++++++++++++++++------------- arch/x86/kernel/cpu/sgx/sgx.h | 2 ++ 2 files changed, 37 insertions(+), 22 deletions(-) diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c index e1dde431a400..ce316bd5e5bb 100644 --- a/arch/x86/kernel/cpu/sgx/main.c +++ b/arch/x86/kernel/cpu/sgx/main.c @@ -283,6 +283,40 @@ static void sgx_reclaimer_write(struct sgx_epc_page *epc_page, mutex_unlock(&encl->lock); } +/** + * sgx_isolate_epc_pages() - Isolate pages from an LRU for reclaim + * @lru: LRU from which to reclaim + * @nr_to_scan: Number of pages to scan for reclaim + * @dst: Destination list to hold the isolated pages + */ +void sgx_isolate_epc_pages(struct sgx_epc_lru_lists *lru, size_t nr_to_scan, + struct list_head *dst) +{ + struct sgx_encl_page *encl_page; + struct sgx_epc_page *epc_page; + + spin_lock(&lru->lock); + for (; nr_to_scan > 0; --nr_to_scan) { + epc_page = list_first_entry_or_null(&lru->reclaimable, struct sgx_epc_page, list); + if (!epc_page) + break; + + encl_page = epc_page->encl_page; + + if (kref_get_unless_zero(&encl_page->encl->refcount)) { + sgx_epc_page_set_state(epc_page, SGX_EPC_PAGE_RECLAIM_IN_PROGRESS); + list_move_tail(&epc_page->list, dst); + } else { + /* The owner is freeing the page, remove it from the + * LRU list + */ + sgx_epc_page_reset_state(epc_page); + list_del_init(&epc_page->list); + } + } + spin_unlock(&lru->lock); +} + /** * sgx_reclaim_epc_pages() - Reclaim EPC pages from the consumers * @nr_to_scan: Number of EPC pages to scan for reclaim @@ -310,28 +344,7 @@ size_t sgx_reclaim_epc_pages(size_t nr_to_scan, bool ignore_age) size_t ret; size_t i; - spin_lock(&sgx_global_lru.lock); - for (i = 0; i < SGX_NR_TO_SCAN; i++) { - epc_page = list_first_entry_or_null(&sgx_global_lru.reclaimable, - struct sgx_epc_page, list); - if (!epc_page) - break; - - list_del_init(&epc_page->list); - encl_page = epc_page->encl_page; - - if (kref_get_unless_zero(&encl_page->encl->refcount) != 0) { - sgx_epc_page_set_state(epc_page, SGX_EPC_PAGE_RECLAIM_IN_PROGRESS); - list_move_tail(&epc_page->list, &iso); - } else { - /* The owner is freeing the page, remove it from the - * LRU list - */ - sgx_epc_page_reset_state(epc_page); - list_del_init(&epc_page->list); - } - } - spin_unlock(&sgx_global_lru.lock); + sgx_isolate_epc_pages(&sgx_global_lru, nr_to_scan, &iso); if (list_empty(&iso)) return 0; diff --git a/arch/x86/kernel/cpu/sgx/sgx.h b/arch/x86/kernel/cpu/sgx/sgx.h index aa4ec2c0ce96..7e21192b87a8 100644 --- a/arch/x86/kernel/cpu/sgx/sgx.h +++ b/arch/x86/kernel/cpu/sgx/sgx.h @@ -178,6 +178,8 @@ int sgx_drop_epc_page(struct sgx_epc_page *page); struct sgx_epc_page *sgx_alloc_epc_page(void *owner, bool reclaim); bool sgx_epc_oom(struct sgx_epc_lru_lists *lrus); size_t sgx_reclaim_epc_pages(size_t nr_to_scan, bool ignore_age); +void sgx_isolate_epc_pages(struct sgx_epc_lru_lists *lrus, size_t nr_to_scan, + struct list_head *dst); void sgx_ipi_cb(void *info); -- 2.25.1