lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Tue, 30 Apr 2024 12:51:05 -0700
From: Haitao Huang <haitao.huang@...ux.intel.com>
To: jarkko@...nel.org,
	dave.hansen@...ux.intel.com,
	kai.huang@...el.com,
	tj@...nel.org,
	mkoutny@...e.com,
	linux-kernel@...r.kernel.org,
	linux-sgx@...r.kernel.org,
	x86@...nel.org,
	cgroups@...r.kernel.org,
	tglx@...utronix.de,
	mingo@...hat.com,
	bp@...en8.de,
	hpa@...or.com,
	sohil.mehta@...el.com,
	tim.c.chen@...ux.intel.com
Cc: zhiquan1.li@...el.com,
	kristen@...ux.intel.com,
	seanjc@...gle.com,
	zhanb@...rosoft.com,
	anakrish@...rosoft.com,
	mikko.ylinen@...ux.intel.com,
	yangjie@...rosoft.com,
	chrisyan@...rosoft.com
Subject: [PATCH v13 11/14] x86/sgx: Abstract check for global reclaimable pages

From: Kristen Carlson Accardi <kristen@...ux.intel.com>

For the global reclaimer to determine if any page available for
reclamation at the global level, it currently only checks for emptiness
of the global LRU. That will be inadequate when pages are tracked in
multiple LRUs, one per cgroup. For this purpose, create a new helper,
sgx_can_reclaim_global(), to abstract this check. Currently it only
checks the global LRU, later will check emptiness of LRUs of all cgroups
when per-cgroup tracking is turned on.

Replace all the checks for emptiness of the global LRU,
list_empty(&sgx_global_lru.reclaimable), with calls to
sgx_can_reclaim_global().

Rename sgx_should_reclaim() to sgx_should_reclaim_global() as it is used
to check if a global reclamation should be performed.

Co-developed-by: Sean Christopherson <sean.j.christopherson@...el.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@...el.com>
Signed-off-by: Kristen Carlson Accardi <kristen@...ux.intel.com>
Co-developed-by: Haitao Huang <haitao.huang@...ux.intel.com>
Signed-off-by: Haitao Huang <haitao.huang@...ux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko@...nel.org>
---
V13:
- Rename sgx_can_reclaim() to sgx_can_reclaim_global() and
sgx_should_reclaim() to sgx_should_reclaim_global(). (Kai)

V10:
- Add comments for the new function. (Jarkko)

V7:
- Split this out from the big patch, #10 in V6. (Dave, Kai)
---
 arch/x86/kernel/cpu/sgx/main.c | 22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c
index f1bd15620b83..92bd3151a589 100644
--- a/arch/x86/kernel/cpu/sgx/main.c
+++ b/arch/x86/kernel/cpu/sgx/main.c
@@ -36,6 +36,14 @@ static inline struct sgx_epc_lru_list *sgx_epc_page_lru(struct sgx_epc_page *epc
 	return &sgx_global_lru;
 }
 
+/*
+ * Check if there is any reclaimable page at global level.
+ */
+static inline bool sgx_can_reclaim_global(void)
+{
+	return !list_empty(&sgx_global_lru.reclaimable);
+}
+
 static atomic_long_t sgx_nr_free_pages = ATOMIC_LONG_INIT(0);
 
 /* Nodes with one or more EPC sections. */
@@ -387,10 +395,10 @@ unsigned int sgx_reclaim_pages(struct sgx_epc_lru_list *lru, struct mm_struct *c
 	return cnt;
 }
 
-static bool sgx_should_reclaim(unsigned long watermark)
+static bool sgx_should_reclaim_global(unsigned long watermark)
 {
 	return atomic_long_read(&sgx_nr_free_pages) < watermark &&
-	       !list_empty(&sgx_global_lru.reclaimable);
+		sgx_can_reclaim_global();
 }
 
 static void sgx_reclaim_pages_global(struct mm_struct *charge_mm)
@@ -405,7 +413,7 @@ static void sgx_reclaim_pages_global(struct mm_struct *charge_mm)
  */
 void sgx_reclaim_direct(void)
 {
-	if (sgx_should_reclaim(SGX_NR_LOW_PAGES))
+	if (sgx_should_reclaim_global(SGX_NR_LOW_PAGES))
 		sgx_reclaim_pages_global(current->mm);
 }
 
@@ -426,9 +434,9 @@ static int ksgxd(void *p)
 
 		wait_event_freezable(ksgxd_waitq,
 				     kthread_should_stop() ||
-				     sgx_should_reclaim(SGX_NR_HIGH_PAGES));
+				     sgx_should_reclaim_global(SGX_NR_HIGH_PAGES));
 
-		if (sgx_should_reclaim(SGX_NR_HIGH_PAGES))
+		if (sgx_should_reclaim_global(SGX_NR_HIGH_PAGES))
 			/* Indirect reclaim, no mm to charge, so NULL: */
 			sgx_reclaim_pages_global(NULL);
 
@@ -592,7 +600,7 @@ struct sgx_epc_page *sgx_alloc_epc_page(void *owner, enum sgx_reclaim reclaim)
 			break;
 		}
 
-		if (list_empty(&sgx_global_lru.reclaimable)) {
+		if (!sgx_can_reclaim_global()) {
 			page = ERR_PTR(-ENOMEM);
 			break;
 		}
@@ -620,7 +628,7 @@ struct sgx_epc_page *sgx_alloc_epc_page(void *owner, enum sgx_reclaim reclaim)
 		sgx_put_cg(sgx_cg);
 	}
 
-	if (sgx_should_reclaim(SGX_NR_LOW_PAGES))
+	if (sgx_should_reclaim_global(SGX_NR_LOW_PAGES))
 		wake_up(&ksgxd_waitq);
 
 	return page;
-- 
2.25.1


Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ