From patchwork Thu Mar 28 00:22:25 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Haitao Huang X-Patchwork-Id: 13607738 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.19]) (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 88C69286AC; Thu, 28 Mar 2024 00:22:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.19 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711585372; cv=none; b=Nam2m9EOZ5UXYqVil1ZmG5ImkehomakyKaVay/UDm+z7sqfLDwY41p38fkr+y1sNmbXm/PUvVwe+Jj9pggY4RZygHPvxeXK1Trv1uBf4ZCaGeg2tOtYhZ7bAw104Uf8k+lMXnIn9Jnri5x18YPIwNJZvinTxaNGpsFilwO/VInI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711585372; c=relaxed/simple; bh=NR4vdjfW1KvfbUY/L+oJwEGaJJvA/QPUr4TZxNfEVn4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=pUKzwisQNKbaxgCM+t0rqnpGROECY0RrvIRxE8bFGo+p9wE5ApSQtEuJxD4ZbuqYyN7PhTtEQYAvzfApuxEAC7D0fLqbyS2KereoL2DhMZKDx7xK1rnCijQcL+ixmx/ZcWtXBFKBccaF9QNkyb3g+BEtvw9oE4Aq3l7GCSK5xQA= 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=cC7O/Vhm; arc=none smtp.client-ip=192.198.163.19 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="cC7O/Vhm" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1711585369; x=1743121369; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=NR4vdjfW1KvfbUY/L+oJwEGaJJvA/QPUr4TZxNfEVn4=; b=cC7O/VhmNP6qE/oI3QA8y61dUVaeRp82W0AIfNemxSjWBLxrNddfYWUq Bp5OsDSR9987msa8U15iDVBpbaZrLAroNjAt5t7W9Z9vXE3RPrqATNH6t J/5/LnLqlvf0oGSXUJLb2Y3J/LpMVKiGqM58TpmpSz6UMJKdg7YqKG5oY IxS30nxyKhwu5sbdGYMRYjfWi2SiIBMKO4ZdnBasKlhenUci6mokXgNvc 1oP4rUk0zpLrMjvwkd9QS0V5SHNks1Y5rtoZ5l7mqQL0ezR0R51eu06jR kpxhrpzRMn+gpe0FTtgq6t1+COqGpFJam2EmQKUO5/evJsn0ekAAROLp8 g==; X-CSE-ConnectionGUID: Qy8QRJaYT4mI92yWjxueLQ== X-CSE-MsgGUID: dSWjnj4jRm6fA+lPPEfBkg== X-IronPort-AV: E=McAfee;i="6600,9927,11026"; a="6580719" X-IronPort-AV: E=Sophos;i="6.07,160,1708416000"; d="scan'208";a="6580719" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by fmvoesa113.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Mar 2024 17:22:32 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.07,160,1708416000"; d="scan'208";a="16411811" Received: from b4969161e530.jf.intel.com ([10.165.56.46]) by orviesa009.jf.intel.com with ESMTP; 27 Mar 2024 17:22:32 -0700 From: Haitao Huang To: jarkko@kernel.org, dave.hansen@linux.intel.com, kai.huang@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 v10 10/14] x86/sgx: Charge mem_cgroup for per-cgroup reclamation Date: Wed, 27 Mar 2024 17:22:25 -0700 Message-Id: <20240328002229.30264-11-haitao.huang@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240328002229.30264-1-haitao.huang@linux.intel.com> References: <20240328002229.30264-1-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 Enclave Page Cache(EPC) memory can be swapped out to regular system memory, and the consumed memory should be charged to a proper mem_cgroup. Currently the selection of mem_cgroup to charge is done in sgx_encl_get_mem_cgroup(). But it considers all contexts other than the ksgxd thread are user processes. With the new EPC cgroup implementation, the swapping can also happen in EPC cgroup work-queue threads. In those cases, it improperly selects the root mem_cgroup to charge for the RAM usage. Remove current_is_ksgxd() and change sgx_encl_get_mem_cgroup() to take an additional argument to explicitly specify the mm struct to charge for allocations. Callers from background kthreads not associated with a charging mm struct would set it to NULL, while callers in user process contexts set it to current->mm. Internally, it handles the case when the charging mm given is NULL, by searching for an mm struct from enclave's mm_list. Signed-off-by: Haitao Huang Reported-by: Mikko Ylinen --- V10: - Pass mm struct instead of a boolean 'indirect'. (Dave, Jarkko) V9: - Reduce number of if statements. (Tim) V8: - Limit text paragraphs to 80 characters wide. (Jarkko) --- arch/x86/kernel/cpu/sgx/encl.c | 29 ++++++++++++++-------------- arch/x86/kernel/cpu/sgx/encl.h | 3 +-- arch/x86/kernel/cpu/sgx/epc_cgroup.c | 10 ++++++---- arch/x86/kernel/cpu/sgx/main.c | 29 +++++++++++++--------------- arch/x86/kernel/cpu/sgx/sgx.h | 2 +- 5 files changed, 36 insertions(+), 37 deletions(-) diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c index f474179b6f77..7b77dad41daf 100644 --- a/arch/x86/kernel/cpu/sgx/encl.c +++ b/arch/x86/kernel/cpu/sgx/encl.c @@ -993,23 +993,23 @@ static int __sgx_encl_get_backing(struct sgx_encl *encl, unsigned long page_inde } /* - * When called from ksgxd, returns the mem_cgroup of a struct mm stored - * in the enclave's mm_list. When not called from ksgxd, just returns - * the mem_cgroup of the current task. + * Find the mem_cgroup to charge for memory allocated on behalf of an enclave. + * + * Used in sgx_encl_alloc_backing() for backing store allocation. + * + * Return the mem_cgroup of the given charge_mm. Otherwise return the mem_cgroup + * of a struct mm stored in the enclave's mm_list. */ -static struct mem_cgroup *sgx_encl_get_mem_cgroup(struct sgx_encl *encl) +static struct mem_cgroup *sgx_encl_get_mem_cgroup(struct sgx_encl *encl, + struct mm_struct *charge_mm) { struct mem_cgroup *memcg = NULL; struct sgx_encl_mm *encl_mm; int idx; - /* - * If called from normal task context, return the mem_cgroup - * of the current task's mm. The remainder of the handling is for - * ksgxd. - */ - if (!current_is_ksgxd()) - return get_mem_cgroup_from_mm(current->mm); + /* Use the charge_mm if given. */ + if (charge_mm) + return get_mem_cgroup_from_mm(charge_mm); /* * Search the enclave's mm_list to find an mm associated with @@ -1047,8 +1047,9 @@ static struct mem_cgroup *sgx_encl_get_mem_cgroup(struct sgx_encl *encl) * @encl: an enclave pointer * @page_index: enclave page index * @backing: data for accessing backing storage for the page + * @charge_mm: the mm to charge for the allocation * - * When called from ksgxd, sets the active memcg from one of the + * When charge_mm is NULL, sets the active memcg from one of the * mms in the enclave's mm_list prior to any backing page allocation, * in order to ensure that shmem page allocations are charged to the * enclave. Create a backing page for loading data back into an EPC page with @@ -1060,9 +1061,9 @@ static struct mem_cgroup *sgx_encl_get_mem_cgroup(struct sgx_encl *encl) * -errno otherwise. */ int sgx_encl_alloc_backing(struct sgx_encl *encl, unsigned long page_index, - struct sgx_backing *backing) + struct sgx_backing *backing, struct mm_struct *charge_mm) { - struct mem_cgroup *encl_memcg = sgx_encl_get_mem_cgroup(encl); + struct mem_cgroup *encl_memcg = sgx_encl_get_mem_cgroup(encl, charge_mm); struct mem_cgroup *memcg = set_active_memcg(encl_memcg); int ret; diff --git a/arch/x86/kernel/cpu/sgx/encl.h b/arch/x86/kernel/cpu/sgx/encl.h index fe15ade02ca1..5ce9d108290f 100644 --- a/arch/x86/kernel/cpu/sgx/encl.h +++ b/arch/x86/kernel/cpu/sgx/encl.h @@ -103,12 +103,11 @@ static inline int sgx_encl_find(struct mm_struct *mm, unsigned long addr, int sgx_encl_may_map(struct sgx_encl *encl, unsigned long start, unsigned long end, unsigned long vm_flags); -bool current_is_ksgxd(void); void sgx_encl_release(struct kref *ref); int sgx_encl_mm_add(struct sgx_encl *encl, struct mm_struct *mm); const cpumask_t *sgx_encl_cpumask(struct sgx_encl *encl); int sgx_encl_alloc_backing(struct sgx_encl *encl, unsigned long page_index, - struct sgx_backing *backing); + struct sgx_backing *backing, struct mm_struct *charge_mm); void sgx_encl_put_backing(struct sgx_backing *backing); int sgx_encl_test_and_clear_young(struct mm_struct *mm, struct sgx_encl_page *page); diff --git a/arch/x86/kernel/cpu/sgx/epc_cgroup.c b/arch/x86/kernel/cpu/sgx/epc_cgroup.c index 3ca89b1fb7e2..1defbf213e8d 100644 --- a/arch/x86/kernel/cpu/sgx/epc_cgroup.c +++ b/arch/x86/kernel/cpu/sgx/epc_cgroup.c @@ -111,6 +111,7 @@ static bool sgx_cgroup_lru_empty(struct misc_cg *root) /** * sgx_cgroup_reclaim_pages() - reclaim EPC from a cgroup tree * @root: The root of cgroup tree to reclaim from. + * @charge_mm: The mm to charge for backing store allocation. * * This function performs a pre-order walk in the cgroup tree under the given * root, attempting to reclaim pages at each node until a fixed number of pages @@ -124,7 +125,7 @@ static bool sgx_cgroup_lru_empty(struct misc_cg *root) * triggering reclamation, and call cond_resched() in between iterations to * avoid indefinite blocking. */ -static void sgx_cgroup_reclaim_pages(struct misc_cg *root) +static void sgx_cgroup_reclaim_pages(struct misc_cg *root, struct mm_struct *charge_mm) { struct cgroup_subsys_state *css_root; struct cgroup_subsys_state *pos; @@ -141,7 +142,7 @@ static void sgx_cgroup_reclaim_pages(struct misc_cg *root) rcu_read_unlock(); sgx_cg = sgx_cgroup_from_misc_cg(css_misc(pos)); - cnt += sgx_reclaim_pages(&sgx_cg->lru); + cnt += sgx_reclaim_pages(&sgx_cg->lru, charge_mm); rcu_read_lock(); css_put(pos); @@ -203,7 +204,8 @@ static void sgx_cgroup_reclaim_work_func(struct work_struct *work) * blocked until a worker makes its way through the global work queue. */ while (sgx_cgroup_should_reclaim(sgx_cg)) { - sgx_cgroup_reclaim_pages(sgx_cg->cg); + /* Indirect reclaim, no mm to charge, so NULL: */ + sgx_cgroup_reclaim_pages(sgx_cg->cg, NULL); cond_resched(); } } @@ -253,7 +255,7 @@ int sgx_cgroup_try_charge(struct sgx_cgroup *sgx_cg, enum sgx_reclaim reclaim) return -EBUSY; } - sgx_cgroup_reclaim_pages(sgx_cg->cg); + sgx_cgroup_reclaim_pages(sgx_cg->cg, current->mm); cond_resched(); } diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c index 9f6594317ce4..c94f8b49e6f2 100644 --- a/arch/x86/kernel/cpu/sgx/main.c +++ b/arch/x86/kernel/cpu/sgx/main.c @@ -253,8 +253,8 @@ static void sgx_encl_ewb(struct sgx_epc_page *epc_page, } } -static void sgx_reclaimer_write(struct sgx_epc_page *epc_page, - struct sgx_backing *backing) +static void sgx_reclaimer_write(struct sgx_epc_page *epc_page, struct sgx_backing *backing, + struct mm_struct *charge_mm) { struct sgx_encl_page *encl_page = epc_page->owner; struct sgx_encl *encl = encl_page->encl; @@ -270,7 +270,7 @@ static void sgx_reclaimer_write(struct sgx_epc_page *epc_page, if (!encl->secs_child_cnt && test_bit(SGX_ENCL_INITIALIZED, &encl->flags)) { ret = sgx_encl_alloc_backing(encl, PFN_DOWN(encl->size), - &secs_backing); + &secs_backing, charge_mm); if (ret) goto out; @@ -289,6 +289,7 @@ static void sgx_reclaimer_write(struct sgx_epc_page *epc_page, /** * sgx_reclaim_pages() - Attempt to reclaim a fixed number of pages from an LRU * @lru: The LRU from which pages are reclaimed. + * @charge_mm: The mm to charge for backing store allocation. * * Take a fixed number of pages from the head of a given LRU and reclaim them to * the enclave's private shmem files. Skip the pages, which have been accessed @@ -304,7 +305,7 @@ static void sgx_reclaimer_write(struct sgx_epc_page *epc_page, * * Return: Number of pages attempted for reclamation. */ -unsigned int sgx_reclaim_pages(struct sgx_epc_lru_list *lru) +unsigned int sgx_reclaim_pages(struct sgx_epc_lru_list *lru, struct mm_struct *charge_mm) { struct sgx_epc_page *chunk[SGX_NR_TO_SCAN]; struct sgx_backing backing[SGX_NR_TO_SCAN]; @@ -344,7 +345,7 @@ unsigned int sgx_reclaim_pages(struct sgx_epc_lru_list *lru) page_index = PFN_DOWN(encl_page->desc - encl_page->encl->base); mutex_lock(&encl_page->encl->lock); - ret = sgx_encl_alloc_backing(encl_page->encl, page_index, &backing[i]); + ret = sgx_encl_alloc_backing(encl_page->encl, page_index, &backing[i], charge_mm); if (ret) { mutex_unlock(&encl_page->encl->lock); goto skip; @@ -376,7 +377,7 @@ unsigned int sgx_reclaim_pages(struct sgx_epc_lru_list *lru) continue; encl_page = epc_page->owner; - sgx_reclaimer_write(epc_page, &backing[i]); + sgx_reclaimer_write(epc_page, &backing[i], charge_mm); kref_put(&encl_page->encl->refcount, sgx_encl_release); epc_page->flags &= ~SGX_EPC_PAGE_RECLAIMER_TRACKED; @@ -393,9 +394,9 @@ static bool sgx_should_reclaim(unsigned long watermark) !list_empty(&sgx_global_lru.reclaimable); } -static void sgx_reclaim_pages_global(void) +static void sgx_reclaim_pages_global(struct mm_struct *charge_mm) { - sgx_reclaim_pages(&sgx_global_lru); + sgx_reclaim_pages(&sgx_global_lru, charge_mm); } /* @@ -406,7 +407,7 @@ static void sgx_reclaim_pages_global(void) void sgx_reclaim_direct(void) { if (sgx_should_reclaim(SGX_NR_LOW_PAGES)) - sgx_reclaim_pages_global(); + sgx_reclaim_pages_global(current->mm); } static int ksgxd(void *p) @@ -429,7 +430,8 @@ static int ksgxd(void *p) sgx_should_reclaim(SGX_NR_HIGH_PAGES)); if (sgx_should_reclaim(SGX_NR_HIGH_PAGES)) - sgx_reclaim_pages_global(); + /* Indirect reclaim, no mm to charge, so NULL: */ + sgx_reclaim_pages_global(NULL); cond_resched(); } @@ -452,11 +454,6 @@ static bool __init sgx_page_reclaimer_init(void) return true; } -bool current_is_ksgxd(void) -{ - return current == ksgxd_tsk; -} - static struct sgx_epc_page *__sgx_alloc_epc_page_from_node(int nid) { struct sgx_numa_node *node = &sgx_numa_nodes[nid]; @@ -615,7 +612,7 @@ struct sgx_epc_page *sgx_alloc_epc_page(void *owner, enum sgx_reclaim reclaim) * Need to do a global reclamation if cgroup was not full but free * physical pages run out, causing __sgx_alloc_epc_page() to fail. */ - sgx_reclaim_pages_global(); + sgx_reclaim_pages_global(current->mm); cond_resched(); } diff --git a/arch/x86/kernel/cpu/sgx/sgx.h b/arch/x86/kernel/cpu/sgx/sgx.h index 954f02efb516..689cec353d6f 100644 --- a/arch/x86/kernel/cpu/sgx/sgx.h +++ b/arch/x86/kernel/cpu/sgx/sgx.h @@ -119,7 +119,7 @@ void sgx_reclaim_direct(void); void sgx_mark_page_reclaimable(struct sgx_epc_page *page); int sgx_unmark_page_reclaimable(struct sgx_epc_page *page); struct sgx_epc_page *sgx_alloc_epc_page(void *owner, enum sgx_reclaim reclaim); -unsigned int sgx_reclaim_pages(struct sgx_epc_lru_list *lru); +unsigned int sgx_reclaim_pages(struct sgx_epc_lru_list *lru, struct mm_struct *charge_mm); void sgx_ipi_cb(void *info);