linux-kernel - [tip:numa/core] sched, numa, mm/mpol: Make mempolicy home-node aware

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>] [day] [month] [year] [list]

Message-ID: <tip-70bc6583401e9a8ad946e9a80df5cb2627c879b5@git.kernel.org>
Date:	Sun, 28 Oct 2012 10:04:35 -0700
From:	tip-bot for Peter Zijlstra <a.p.zijlstra@...llo.nl>
To:	linux-tip-commits@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org, hpa@...or.com, mingo@...nel.org,
	torvalds@...ux-foundation.org, a.p.zijlstra@...llo.nl,
	pjt@...gle.com, cl@...ux.com, riel@...hat.com,
	akpm@...ux-foundation.org, Lee.Schermerhorn@...com,
	tglx@...utronix.de
Subject: [tip:numa/core] sched, numa, mm/mpol:
  Make mempolicy home-node aware

Commit-ID:  70bc6583401e9a8ad946e9a80df5cb2627c879b5
Gitweb:     http://git.kernel.org/tip/70bc6583401e9a8ad946e9a80df5cb2627c879b5
Author:     Peter Zijlstra <a.p.zijlstra@...llo.nl>
AuthorDate: Sat, 3 Mar 2012 17:05:54 +0100
Committer:  Ingo Molnar <mingo@...nel.org>
CommitDate: Sun, 28 Oct 2012 17:31:09 +0100

sched, numa, mm/mpol: Make mempolicy home-node aware

Add another layer of fallback policy to make the home node concept
useful from a memory allocation PoV.

This changes the mpol order to:

 - vma->vm_ops->get_policy	[if applicable]
 - vma->vm_policy		[if applicable]
 - task->mempolicy
 - tsk_home_node() preferred	[NEW]
 - default_policy

Note that the tsk_home_node() policy has Migrate-on-Fault enabled to
facilitate efficient on-demand memory migration.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@...llo.nl>
Cc: Paul Turner <pjt@...gle.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@...com>
Cc: Christoph Lameter <cl@...ux.com>
Cc: Rik van Riel <riel@...hat.com>
Cc: Andrew Morton <akpm@...ux-foundation.org>
Cc: Linus Torvalds <torvalds@...ux-foundation.org>
Link: http://lkml.kernel.org/n/tip-ybn5oygsqXZa6jtwpwjywmdu@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@...nel.org>
---
 mm/mempolicy.c |   29 +++++++++++++++++++++++++++--
 1 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 5ee326c..97e6d99 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -117,6 +117,22 @@ static struct mempolicy default_policy = {
 	.flags = MPOL_F_LOCAL,
 };
 
+static struct mempolicy preferred_node_policy[MAX_NUMNODES];
+
+static struct mempolicy *get_task_policy(struct task_struct *p)
+{
+	struct mempolicy *pol = p->mempolicy;
+	int node;
+
+	if (!pol) {
+		node = tsk_home_node(p);
+		if (node != -1)
+			pol = &preferred_node_policy[node];
+	}
+
+	return pol;
+}
+
 static const struct mempolicy_operations {
 	int (*create)(struct mempolicy *pol, const nodemask_t *nodes);
 	/*
@@ -1565,7 +1581,7 @@ asmlinkage long compat_sys_mbind(compat_ulong_t start, compat_ulong_t len,
 struct mempolicy *get_vma_policy(struct task_struct *task,
 		struct vm_area_struct *vma, unsigned long addr)
 {
-	struct mempolicy *pol = task->mempolicy;
+	struct mempolicy *pol = get_task_policy(task);
 
 	if (vma) {
 		if (vma->vm_ops && vma->vm_ops->get_policy) {
@@ -1988,7 +2004,7 @@ retry_cpuset:
  */
 struct page *alloc_pages_current(gfp_t gfp, unsigned order)
 {
-	struct mempolicy *pol = current->mempolicy;
+	struct mempolicy *pol = get_task_policy(current);
 	struct page *page;
 	unsigned int cpuset_mems_cookie;
 
@@ -2450,6 +2466,15 @@ void __init numa_policy_init(void)
 				     sizeof(struct sp_node),
 				     0, SLAB_PANIC, NULL);
 
+	for_each_node(nid) {
+		preferred_node_policy[nid] = (struct mempolicy) {
+			.refcnt = ATOMIC_INIT(1),
+			.mode = MPOL_PREFERRED,
+			.flags = MPOL_F_MOF,
+			.v = { .preferred_node = nid, },
+		};
+	}
+
 	/*
 	 * Set interleaving policy for system init. Interleaving is only
 	 * enabled across suitably sized nodes (default is >= 16MB), or
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/