Skip to contentSkip to conversation

aoe driver v49 performance and usability improvements

PATCH In review Ed Cashin 2 participants 16 messages Aug 28, 2012 – Aug 31, 2012

Subsystems (3)
Documentation Block layer ATA over Ethernet (aoe) driver
lore
Share & tools
lore

Ed Cashin

author
#0 lore raw

cover aoe driver v49 performance and usability improvements

In this resubmission of the patchset, several suggestions from Andrew Morton have been incorporated to clean up the changes. I will not be able to be very responsive during the first part of September, so the sooner you can provide feedback, the better.

These patches go a long way to updating the in-kernel aoe driver with the changes that have been in the coraid.com-distributed version, bringing it from (aoe internal) version 47 to version 49. They apply to commit 23dcfa61bac244e1 of the mainline git tree.

These updates have been too long in coming, but there is reason to be hopeful that once these changes are applied, there is now less of a chance that such a large update gap will occur again for a couple reasons.

For one, the changes between 47 and 49 were originally produced in a form that required a large amount of work before they could be presented to the list in a form that complies with Documenation/Submit*. I have done my best to disentangle the changes and to clean them up. Subsequent changes are more amenable to submission to the LKML and should be easier to prepare soon. Future changes from Coraid are expected to be similarly amenable to LKML submission because of changes we have made for the better in Coraid's development practices in the past few years.

Second, the users of the aoe driver increasingly demand that the in-kernel driver have the same high performance and advanced features as the one distributed at coraid.com.

The plan is to follow up with more changes once this patchset is merged, until the coraid.com-distributed driver and the in-kernel drivers are as close as possible. Some bugfixes from have been backported to this patchset, though, from post-version-49 development. The important thing, though, is to get things started with a minimal and progressive first patchset.

Ed L. Cashin (14):
aoe: for performance support larger packet payloads
aoe: kernel thread handles I/O completions for simple locking
aoe: become I/O request queue handler for increased user control
aoe: use a kernel thread for transmissions
aoe: use packets that work with the smallest-MTU local interface
aoe: failover remote interface based on aoe_deadsecs parameter
aoe: do revalidation steps in order
aoe: disallow unsupported AoE minor addresses
aoe: associate frames with the AoE storage target
aoe: increase net_device reference count while using it
aoe: remove unused code and add cosmetic improvements
aoe: update internal version number to 49
aoe: update copyright year in touched files
aoe: update documentation with new URL and VM settings reference

 Documentation/aoe/aoe.txt   |    9 +-
 MAINTAINERS                 |    2 +-
 drivers/block/aoe/aoe.h     |   85 ++--
 drivers/block/aoe/aoeblk.c  |   89 +---
 drivers/block/aoe/aoechr.c  |   11 +-
 drivers/block/aoe/aoecmd.c  | 1219 ++++++++++++++++++++++++++++---------------
 drivers/block/aoe/aoedev.c  |  161 ++++--
 drivers/block/aoe/aoemain.c |   10 +-
 drivers/block/aoe/aoenet.c  |   61 ++-
 9 files changed, 1076 insertions(+), 571 deletions(-)
Signature · 1 line
1.7.2.5
author
#1 lore raw

PATCH 1/14 aoe: for performance support larger packet payloads

This patch adds the ability to work with large packets composed of a number of segments, using the scatter gather feature of the block layer (biovecs) and the network layer (skb frag array). The motivation is the performance gained by using a packet data payload greater than a page size and by using the network card's scatter gather feature.

Users of the out-of-tree aoe driver already had these changes, but since early 2011, they have complained of increased memory utilization and higher CPU utilization during heavy writes.[1] The commit below appears related, as it disables scatter gather on non-IP protocols inside the harmonize_features function, even when the NIC supports sg.

commit f01a5236bd4b140198fbcc550f085e8361fd73fa
Author: Jesse Gross <[email protected]>
Date: Sun Jan 9 06:23:31 2011 +0000

net offloading: Generalize netif_get_vlan_features().

With that regression in place, transmits always linearize sg AoE packets, but in-kernel users did not have this patch. Before 2.6.38, though, these changes were working to allow sg to increase performance.

1. http://www.spinics.net/lists/linux-mm/msg15184.html

Signed-off-by Ed Cashin <[email protected]>
---
 drivers/block/aoe/aoe.h    |    2 +
 drivers/block/aoe/aoeblk.c |    3 +
 drivers/block/aoe/aoecmd.c |  138 ++++++++++++++++++++++++++++++-------------
 drivers/block/aoe/aoedev.c |    1 +
 drivers/block/aoe/aoenet.c |   13 +++-
 5 files changed, 111 insertions(+), 46 deletions(-)
drivers/block/aoe/aoe.h +2 -0
index db195ab..8ca8c8a 100644
@@ -119,6 +119,8 @@ struct frame {
 	ulong bcnt;
 	sector_t lba;
 	struct sk_buff *skb;
+	struct bio_vec *bv;
+	ulong bv_off;
 };
 
 struct aoeif {
drivers/block/aoe/aoeblk.c +3 -0
index 321de7b..3a8f093 100644
@@ -254,6 +254,7 @@ aoeblk_gdalloc(void *vp)
 {
 	struct aoedev *d = vp;
 	struct gendisk *gd;
+	enum { KB = 1024, MB = KB * KB, READ_AHEAD = MB, };
 	ulong flags;
 
 	gd = alloc_disk(AOE_PARTITIONS);

@@ -279,6 +280,8 @@ aoeblk_gdalloc(void *vp)
 	if (bdi_init(&d->blkq->backing_dev_info))
 		goto err_blkq;
 	spin_lock_irqsave(&d->lock, flags);
+	blk_queue_max_hw_sectors(d->blkq, BLK_DEF_MAX_SECTORS);
+	d->blkq->backing_dev_info.ra_pages = READ_AHEAD / PAGE_CACHE_SIZE;
 	gd->major = AOE_MAJOR;
 	gd->first_minor = d->sysminor * AOE_PARTITIONS;
 	gd->fops = &aoe_bdops;
drivers/block/aoe/aoecmd.c +96 -42

247 lines not on this page · raw message

drivers/block/aoe/aoedev.c +1 -0
index 6b5110a..b2d1fd3 100644
@@ -182,6 +182,7 @@ skbfree(struct sk_buff *skb)
 			"cannot free skb -- memory leaked.");
 		return;
 	}
+	skb->truesize -= skb->data_len;
 	skb_shinfo(skb)->nr_frags = skb->data_len = 0;
 	skb_trim(skb, 0);
 	dev_kfree_skb(skb);
drivers/block/aoe/aoenet.c +9 -4
index 4d3bc0d..0787807 100644
@@ -102,7 +102,9 @@ static int
 aoenet_rcv(struct sk_buff *skb, struct net_device *ifp, struct packet_type *pt, struct net_device *orig_dev)
 {
 	struct aoe_hdr *h;
+	struct aoe_atahdr *ah;
 	u32 n;
+	int sn;
 
 	if (dev_net(ifp) != &init_net)
 		goto exit;

@@ -110,13 +112,16 @@ aoenet_rcv(struct sk_buff *skb, struct net_device *ifp, struct packet_type *pt,
 	skb = skb_share_check(skb, GFP_ATOMIC);
 	if (skb == NULL)
 		return 0;
-	if (skb_linearize(skb))
-		goto exit;
 	if (!is_aoe_netif(ifp))
 		goto exit;
 	skb_push(skb, ETH_HLEN);	/* (1) */
-
-	h = (struct aoe_hdr *) skb_mac_header(skb);
+	sn = sizeof(*h) + sizeof(*ah);
+	if (skb->len >= sn) {
+		sn -= skb_headlen(skb);
+		if (sn > 0 && !__pskb_pull_tail(skb, sn))
+			goto exit;
+	}
+	h = (struct aoe_hdr *) skb->data;
 	n = get_unaligned_be32(&h->tag);
 	if ((h->verfl & AOEFL_RSP) == 0 || (n & 1<<31))
 		goto exit;
Signature · 1 line
1.7.2.5
author
#2 lore raw

PATCH 2/14 aoe: kernel thread handles I/O completions for simple locking

In reply to Ed Cashin

This patch makes the frames the aoe driver uses to track the relationship between bios and packets more flexible and detached, so that they can be passed to an "aoe_ktio" thread for completion of I/O.

The frames are handled much like skbs, with a capped amount of preallocation so that real-world use cases are likely to run smoothly and degenerate gracefully even under memory pressure.

Decoupling I/O completion from the receive path and serializing it in a process makes it easier to think about the correctness of the locking in the driver, especially in the case of a remote MAC address becoming unusable.

Signed-off-by Ed Cashin <[email protected]>
---
 drivers/block/aoe/aoe.h     |   33 ++-
 drivers/block/aoe/aoechr.c  |    3 +-
 drivers/block/aoe/aoecmd.c  |  729 ++++++++++++++++++++++++++++---------------
 drivers/block/aoe/aoedev.c  |   84 +++--
 drivers/block/aoe/aoemain.c |    8 +-
 drivers/block/aoe/aoenet.c  |    6 +-
 6 files changed, 559 insertions(+), 304 deletions(-)
drivers/block/aoe/aoe.h +27 -6
index 8ca8c8a..0cd6c0f 100644
@@ -91,6 +91,7 @@ enum {
 	NTARGETS = 8,
 	NAOEIFS = 8,
 	NSKBPOOLMAX = 128,
+	NFACTIVE = 17,
 
 	TIMERTICK = HZ / 10,
 	MINTIMER = HZ >> 2,

@@ -112,13 +113,16 @@ struct buf {
 };
 
 struct frame {
-	int tag;
+	struct list_head head;
+	u32 tag;
 	ulong waited;
 	struct buf *buf;
+	struct aoetgt *t;		/* parent target I belong to */
 	char *bufaddr;
 	ulong bcnt;
 	sector_t lba;
-	struct sk_buff *skb;
+	struct sk_buff *skb;		/* command skb freed on module exit */
+	struct sk_buff *r_skb;		/* response skb for async processing */
 	struct bio_vec *bv;
 	ulong bv_off;
 };

@@ -133,16 +137,18 @@ struct aoeif {
 struct aoetgt {
 	unsigned char addr[6];
 	ushort nframes;
-	struct frame *frames;
+	struct aoedev *d;			/* parent device I belong to */
+	struct list_head factive[NFACTIVE];	/* hash of active frames */
+	struct list_head ffree;			/* list of free frames */
 	struct aoeif ifs[NAOEIFS];
 	struct aoeif *ifp;	/* current aoeif in use */
 	ushort nout;
 	ushort maxout;
 	u16 lasttag;		/* last tag sent */
 	u16 useme;
+	ulong falloc;
 	ulong lastwadj;		/* last window adjustment */
 	int wpkts, rpkts;
-	int dataref;
 };
 
 struct aoedev {

@@ -169,9 +175,20 @@ struct aoedev {
 	struct buf *inprocess;	/* the one we're currently working on */
 	struct aoetgt *targets[NTARGETS];
 	struct aoetgt **tgt;	/* target in use when working */
-	struct aoetgt **htgt;	/* target needing rexmit assistance */
+	struct aoetgt *htgt;	/* target needing rexmit assistance */
+	ulong ntargets;
+	ulong kicked;
 };
 
+/* kthread tracking */
+struct ktstate {
+	struct completion rendez;
+	struct task_struct *task;
+	wait_queue_head_t *waitq;
+	int (*fn) (void);
+	char *name;
+	spinlock_t *lock;
+};
 
 int aoeblk_init(void);
 void aoeblk_exit(void);

@@ -184,11 +201,14 @@ void aoechr_error(char *);
 
 void aoecmd_work(struct aoedev *d);
 void aoecmd_cfg(ushort aoemajor, unsigned char aoeminor);
-void aoecmd_ata_rsp(struct sk_buff *);
+struct sk_buff *aoecmd_ata_rsp(struct sk_buff *);
 void aoecmd_cfg_rsp(struct sk_buff *);
 void aoecmd_sleepwork(struct work_struct *);
 void aoecmd_cleanslate(struct aoedev *);
+void aoecmd_exit(void);
+int aoecmd_init(void);
 struct sk_buff *aoecmd_ata_id(struct aoedev *);
+void aoe_freetframe(struct frame *);
 
 int aoedev_init(void);
 void aoedev_exit(void);

@@ -196,6 +216,7 @@ struct aoedev *aoedev_by_aoeaddr(int maj, int min);
 struct aoedev *aoedev_by_sysminor_m(ulong sysminor);
 void aoedev_downdev(struct aoedev *d);
 int aoedev_flush(const char __user *str, size_t size);
+void aoe_failbuf(struct aoedev *d, struct buf *buf);
 
 int aoenet_init(void);
 void aoenet_exit(void);
drivers/block/aoe/aoechr.c +1 -2
index e86d206..f145388 100644
@@ -86,10 +86,9 @@ revalidate(const char __user *str, size_t size)
 	if (copy_from_user(buf, str, size))
 		return -EFAULT;
 
-	/* should be e%d.%d format */
 	n = sscanf(buf, "e%d.%d", &major, &minor);
 	if (n != 2) {
-		printk(KERN_ERR "aoe: invalid device specification\n");
+		pr_err("aoe: invalid device specification %s\n", buf);
 		return -EINVAL;
 	}
 	d = aoedev_by_aoeaddr(major, minor);
drivers/block/aoe/aoecmd.c +470 -259

947 lines not on this page · raw message

drivers/block/aoe/aoedev.c +50 -34

110 lines not on this page · raw message

drivers/block/aoe/aoemain.c +6 -2
index 7f83ad9..6fc4b05 100644
@@ -61,6 +61,7 @@ aoe_exit(void)
 
 	aoenet_exit();
 	unregister_blkdev(AOE_MAJOR, DEVICE_NAME);
+	aoecmd_exit();
 	aoechr_exit();
 	aoedev_exit();
 	aoeblk_exit();		/* free cache after de-allocating bufs */

@@ -83,17 +84,20 @@ aoe_init(void)
 	ret = aoenet_init();
 	if (ret)
 		goto net_fail;
+	ret = aoecmd_init();
+	if (ret)
+		goto cmd_fail;
 	ret = register_blkdev(AOE_MAJOR, DEVICE_NAME);
 	if (ret < 0) {
 		printk(KERN_ERR "aoe: can't register major\n");
 		goto blkreg_fail;
 	}
-
 	printk(KERN_INFO "aoe: AoE v%s initialised.\n", VERSION);
 	discover_timer(TINIT);
 	return 0;
-
  blkreg_fail:
+	aoecmd_exit();
+ cmd_fail:
 	aoenet_exit();
  net_fail:
 	aoeblk_exit();
drivers/block/aoe/aoenet.c +5 -1
index 0787807..000eff2 100644
@@ -142,7 +142,8 @@ aoenet_rcv(struct sk_buff *skb, struct net_device *ifp, struct packet_type *pt,
 
 	switch (h->cmd) {
 	case AOECMD_ATA:
-		aoecmd_ata_rsp(skb);
+		/* ata_rsp may keep skb for later processing or give it back */
+		skb = aoecmd_ata_rsp(skb);
 		break;
 	case AOECMD_CFG:
 		aoecmd_cfg_rsp(skb);

@@ -152,6 +153,9 @@ aoenet_rcv(struct sk_buff *skb, struct net_device *ifp, struct packet_type *pt,
 			break;	/* don't complain about vendor commands */
 		printk(KERN_INFO "aoe: unknown cmd %d\n", h->cmd);
 	}
+
+	if (!skb)
+		return 0;
 exit:
 	dev_kfree_skb(skb);
 	return 0;
Signature · 1 line
1.7.2.5
#3 lore raw

Re: [PATCH 02/14] aoe: kernel thread handles I/O completions for simple locking

Quoted 40 lines · On Sat, 25 Aug 2012 10:39:46 -0400 Ed Cashin <[email protected]> wrote:
drivers/block/aoe/aoecmd.c +40 -0
+static int
+kthread(void *vp)
+{
+	struct ktstate *k;
+	DECLARE_WAITQUEUE(wait, current);
+	int more;
+
+	k = vp;
+	current->flags |= PF_NOFREEZE;
+	set_user_nice(current, -10);
+	complete(&k->rendez);	/* tell spawner we're running */
+	do {
+		spin_lock_irq(k->lock);
+		more = k->fn();
+		if (!more) {
+			add_wait_queue(k->waitq, &wait);
+			__set_current_state(TASK_INTERRUPTIBLE);
+		}
+		spin_unlock_irq(k->lock);
+		if (!more) {
+			schedule();
+			remove_wait_queue(k->waitq, &wait);
+		} else
+			cond_resched();
+	} while (!kthread_should_stop());
+	complete(&k->rendez);	/* tell spawner we're stopping */
+	return 0;
+}
+
+static void
+aoe_ktstop(struct ktstate *k)
+{
+	kthread_stop(k->task);
+	wait_for_completion(&k->rendez);
+}
+
+static int
+aoe_ktstart(struct ktstate *k)
+{
+	struct task_struct *task;

drivers/block/aoe/aoecmd.c loop: · line 1017

Quoted 10 lines
drivers/block/aoe/aoecmd.c +10 -0
+
+	init_completion(&k->rendez);
+	task = kthread_run(kthread, k, k->name);
+	if (task == NULL || IS_ERR(task))
+		return -ENOMEM;
+	k->task = task;
+	wait_for_completion(&k->rendez); /* allow kthread to start */
+	init_completion(&k->rendez);	/* for waiting for exit later */
+	return 0;
+}

It's a pretty unlikely thing, but I wonder if there's a way in which aoe_ktstart() can run that second init_completion() _after_ kthread() has run its second complete(). ie: someone runs aoe_ktstop() super-early. If that can happen, the later wait_for_completion() hangs up.

author
#4 lore raw

PATCH 3/14 aoe: become I/O request queue handler for increased user control

In reply to Ed Cashin

To allow users to choose an elevator algorithm for their particular workloads, change from a make_request-style driver to an I/O-request-queue-handler-style driver.

We have to do a couple of things that might be surprising. We manipulate the page _count directly on the assumption that we still have no guarantee that users of the block layer are prohibited from submitting bios containing pages with zero reference counts.[1] If such a prohibition now exists, I can get rid of the _count manipulation.

Just as before this patch, we still keep track of the sk_buffs that the network layer still hasn't finished yet and cap the resources we use with a "pool" of skbs.[2]

Now that the block layer maintains the disk stats, the aoe driver's diskstats function can go away.

1. https://lkml.org/lkml/2007/3/1/374
2. https://lkml.org/lkml/2007/7/6/241

Signed-off-by Ed Cashin <[email protected]>
---
 drivers/block/aoe/aoe.h    |   26 ++--
 drivers/block/aoe/aoeblk.c |   88 ++++----------
 drivers/block/aoe/aoechr.c |    1 +
 drivers/block/aoe/aoecmd.c |  282 +++++++++++++++++++++++++++++++------------
 drivers/block/aoe/aoedev.c |   93 ++++++++++-----
 5 files changed, 308 insertions(+), 182 deletions(-)
drivers/block/aoe/aoe.h +14 -12
index 0cd6c0f..8c4f6d9 100644
@@ -90,7 +90,7 @@ enum {
 	MIN_BUFS = 16,
 	NTARGETS = 8,
 	NAOEIFS = 8,
-	NSKBPOOLMAX = 128,
+	NSKBPOOLMAX = 256,
 	NFACTIVE = 17,
 
 	TIMERTICK = HZ / 10,

@@ -100,30 +100,26 @@ enum {
 };
 
 struct buf {
-	struct list_head bufs;
-	ulong stime;	/* for disk stats */
-	ulong flags;
 	ulong nframesout;
 	ulong resid;
 	ulong bv_resid;
-	ulong bv_off;
 	sector_t sector;
 	struct bio *bio;
 	struct bio_vec *bv;
+	struct request *rq;
 };
 
 struct frame {
 	struct list_head head;
 	u32 tag;
 	ulong waited;
-	struct buf *buf;
 	struct aoetgt *t;		/* parent target I belong to */
-	char *bufaddr;
-	ulong bcnt;
 	sector_t lba;
 	struct sk_buff *skb;		/* command skb freed on module exit */
 	struct sk_buff *r_skb;		/* response skb for async processing */
+	struct buf *buf;
 	struct bio_vec *bv;
+	ulong bcnt;
 	ulong bv_off;
 };
 

@@ -161,6 +157,7 @@ struct aoedev {
 	u16 rttavg;		/* round trip average of requests/responses */
 	u16 mintimer;
 	u16 fw_ver;		/* version of blade's firmware */
+	ulong ref;
 	struct work_struct work;/* disk create work struct */
 	struct gendisk *gd;
 	struct request_queue *blkq;

@@ -168,11 +165,13 @@ struct aoedev {
 	sector_t ssize;
 	struct timer_list timer;
 	spinlock_t lock;
-	struct sk_buff_head sendq;
 	struct sk_buff_head skbpool;
 	mempool_t *bufpool;	/* for deadlock-free Buf allocation */
-	struct list_head bufq;	/* queue of bios to work on */
-	struct buf *inprocess;	/* the one we're currently working on */
+	struct {		/* pointers to work in progress */
+		struct buf *buf;
+		struct bio *nxbio;
+		struct request *rq;
+	} ip;
 	struct aoetgt *targets[NTARGETS];
 	struct aoetgt **tgt;	/* target in use when working */
 	struct aoetgt *htgt;	/* target needing rexmit assistance */

@@ -209,6 +208,8 @@ void aoecmd_exit(void);
 int aoecmd_init(void);
 struct sk_buff *aoecmd_ata_id(struct aoedev *);
 void aoe_freetframe(struct frame *);
+void aoe_flush_iocq(void);
+void aoe_end_request(struct aoedev *, struct request *, int);
 
 int aoedev_init(void);
 void aoedev_exit(void);

@@ -216,7 +217,8 @@ struct aoedev *aoedev_by_aoeaddr(int maj, int min);
 struct aoedev *aoedev_by_sysminor_m(ulong sysminor);
 void aoedev_downdev(struct aoedev *d);
 int aoedev_flush(const char __user *str, size_t size);
-void aoe_failbuf(struct aoedev *d, struct buf *buf);
+void aoe_failbuf(struct aoedev *, struct buf *);
+void aoedev_put(struct aoedev *);
 
 int aoenet_init(void);
 void aoenet_exit(void);
drivers/block/aoe/aoeblk.c +26 -62

136 lines not on this page · raw message

drivers/block/aoe/aoechr.c +1 -0
index f145388..3557f0d 100644
@@ -106,6 +106,7 @@ loop:
 		spin_lock_irqsave(&d->lock, flags);
 		goto loop;
 	}
+	aoedev_put(d);
 	if (skb) {
 		struct sk_buff_head queue;
 		__skb_queue_head_init(&queue);
drivers/block/aoe/aoecmd.c +203 -79

450 lines not on this page · raw message

drivers/block/aoe/aoedev.c +64 -29

194 lines not on this page · raw message

Signature · 1 line
1.7.2.5
author
#5 lore raw

PATCH 4/14 aoe: use a kernel thread for transmissions

In reply to Ed Cashin

The dev_queue_xmit function needs to have interrupts enabled, so the most simple way to get the locking right but still fulfill that requirement is to use a process that can call dev_queue_xmit serially over queued transmissions.

Signed-off-by Ed Cashin <[email protected]>
---
 drivers/block/aoe/aoe.h    |    2 ++
 drivers/block/aoe/aoecmd.c |    4 ++--
 drivers/block/aoe/aoenet.c |   37 ++++++++++++++++++++++++++++++++++++-
 3 files changed, 40 insertions(+), 3 deletions(-)
drivers/block/aoe/aoe.h +2 -0
index 8c4f6d9..d0087de1 100644
@@ -210,6 +210,8 @@ struct sk_buff *aoecmd_ata_id(struct aoedev *);
 void aoe_freetframe(struct frame *);
 void aoe_flush_iocq(void);
 void aoe_end_request(struct aoedev *, struct request *, int);
+int aoe_ktstart(struct ktstate *k);
+void aoe_ktstop(struct ktstate *k);
 
 int aoedev_init(void);
 void aoedev_exit(void);
drivers/block/aoe/aoecmd.c +2 -2
index dd7e397..5cc4d3a 100644
@@ -1109,14 +1109,14 @@ kthread(void *vp)
 	return 0;
 }
 
-static void
+void
 aoe_ktstop(struct ktstate *k)
 {
 	kthread_stop(k->task);
 	wait_for_completion(&k->rendez);
 }
 
-static int
+int
 aoe_ktstart(struct ktstate *k)
 {
 	struct task_struct *task;
drivers/block/aoe/aoenet.c +36 -1
index 000eff2..5f43710 100644
@@ -33,6 +33,9 @@ static char aoe_iflist[IFLISTSZ];
 module_param_string(aoe_iflist, aoe_iflist, IFLISTSZ, 0600);
 MODULE_PARM_DESC(aoe_iflist, "aoe_iflist=\"dev1 [dev2 ...]\"");
 
+static wait_queue_head_t txwq;
+static struct ktstate kts;
+
 #ifndef MODULE
 static int __init aoe_iflist_setup(char *str)
 {

@@ -44,6 +47,23 @@ static int __init aoe_iflist_setup(char *str)
 __setup("aoe_iflist=", aoe_iflist_setup);
 #endif
 
+static spinlock_t txlock;
+static struct sk_buff_head skbtxq;
+
+/* enters with txlock held */
+static int
+tx(void)
+{
+	struct sk_buff *skb;
+
+	while ((skb = skb_dequeue(&skbtxq))) {
+		spin_unlock_irq(&txlock);
+		dev_queue_xmit(skb);
+		spin_lock_irq(&txlock);
+	}
+	return 0;
+}
+
 int
 is_aoe_netif(struct net_device *ifp)
 {

@@ -88,10 +108,14 @@ void
 aoenet_xmit(struct sk_buff_head *queue)
 {
 	struct sk_buff *skb, *tmp;
+	ulong flags;
 
 	skb_queue_walk_safe(queue, skb, tmp) {
 		__skb_unlink(skb, queue);
-		dev_queue_xmit(skb);
+		spin_lock_irqsave(&txlock, flags);
+		skb_queue_tail(&skbtxq, skb);
+		spin_unlock_irqrestore(&txlock, flags);
+		wake_up(&txwq);
 	}
 }
 

@@ -169,6 +193,15 @@ static struct packet_type aoe_pt __read_mostly = {
 int __init
 aoenet_init(void)
 {
+	skb_queue_head_init(&skbtxq);
+	init_waitqueue_head(&txwq);
+	spin_lock_init(&txlock);
+	kts.lock = &txlock;
+	kts.fn = tx;
+	kts.waitq = &txwq;
+	kts.name = "aoe_tx";
+	if (aoe_ktstart(&kts))
+		return -EAGAIN;
 	dev_add_pack(&aoe_pt);
 	return 0;
 }

@@ -176,6 +209,8 @@ aoenet_init(void)
 void
 aoenet_exit(void)
 {
+	aoe_ktstop(&kts);
+	skb_queue_purge(&skbtxq);
 	dev_remove_pack(&aoe_pt);
 }
Signature · 1 line
1.7.2.5
author
#6 lore raw

PATCH 5/14 aoe: use packets that work with the smallest-MTU local interface

In reply to Ed Cashin

Users with several network interfaces dedicated to AoE generally do not configure them to support different-sized AoE data payloads on purpose.

For a given AoE target, there will be a set of local network interfaces that can reach it. Using only the payload that will fit in the smallest-sized MTU of all those local interfaces greatly simplifies the driver, especially in failure scenarios.

Signed-off-by Ed Cashin <[email protected]>
---
 drivers/block/aoe/aoe.h    |    7 +-
 drivers/block/aoe/aoecmd.c |  151 ++++++++++++++++++++++++--------------------
 2 files changed, 87 insertions(+), 71 deletions(-)
drivers/block/aoe/aoe.h +4 -3
index d0087de1..ffded64 100644
@@ -125,9 +125,8 @@ struct frame {
 
 struct aoeif {
 	struct net_device *nd;
-	unsigned char lost;
-	unsigned char lostjumbo;
-	ushort maxbcnt;
+	ulong lost;
+	int bcnt;
 };
 
 struct aoetgt {

@@ -144,6 +143,7 @@ struct aoetgt {
 	u16 useme;
 	ulong falloc;
 	ulong lastwadj;		/* last window adjustment */
+	int minbcnt;
 	int wpkts, rpkts;
 };
 

@@ -172,6 +172,7 @@ struct aoedev {
 		struct bio *nxbio;
 		struct request *rq;
 	} ip;
+	ulong maxbcnt;
 	struct aoetgt *targets[NTARGETS];
 	struct aoetgt **tgt;	/* target in use when working */
 	struct aoetgt *htgt;	/* target needing rexmit assistance */
drivers/block/aoe/aoecmd.c +83 -68

229 lines not on this page · raw message

Signature · 1 line
1.7.2.5
author
#7 lore raw

PATCH 6/14 aoe: failover remote interface based on aoe_deadsecs parameter

In reply to Ed Cashin

The aoe_deadsecs module parameter allows the user to specify a hard limit on the number of seconds an AoE command can be retransmitted before the AoE block device is considered to have failed.

Using aoe_deadsecs to determine the time we try using a different remote interface helps to ensure that the hard limit is not reached before we've tried to recover by sending to a different remote port.

As a data storage target, the AoE target is unambiguously identified by its {major, minor} AoE address tuple, and an AoE target can have multiple MAC addresses. However, note that "target" in the driver code and comments means a {major, minor, MAC address} tuple, as in "somewhere to send packets".

Signed-off-by Ed Cashin <[email protected]>
---
 drivers/block/aoe/aoe.h    |    1 -
 drivers/block/aoe/aoecmd.c |    8 +++-----
 2 files changed, 3 insertions(+), 6 deletions(-)
drivers/block/aoe/aoe.h +0 -1
index ffded64..d17b727 100644
@@ -96,7 +96,6 @@ enum {
 	TIMERTICK = HZ / 10,
 	MINTIMER = HZ >> 2,
 	MAXTIMER = HZ << 1,
-	HELPWAIT = 20,
 };
 
 struct buf {
drivers/block/aoe/aoecmd.c +3 -5
index cf196ed..7f9cc44 100644
@@ -632,11 +632,9 @@ rexmit_timer(ulong vp)
 		list_del(pos);
 
 		t = f->t;
-		if (n > HELPWAIT) {
-			/* see if another target can help */
-			if (d->ntargets > 1)
-				d->htgt = t;
-		}
+		if (n > aoe_deadsecs/2)
+			d->htgt = t; /* see if another target can help */
+
 		if (t->nout == t->maxout) {
 			if (t->maxout > 1)
 				t->maxout--;
Signature · 1 line
1.7.2.5
author
#8 lore raw

PATCH 7/14 aoe: do revalidation steps in order

In reply to Ed Cashin

The discovery process begins with an optional AoE config query command and an AoE config query response. Normally when an aoe device is already open, the config query response does not trigger an ATA identify device command to be sent out, since the response contains storage capacity information that, if changed, could surprise the user of the device.

The userland "aoe-revalidate" tool uses a character device to trigger an AoE config query for a particular AoE storage target and an ATA device identify command, even when the device is open.

This change causes the config query to go out first, reflecting the normal discovery sequence. The responses could come back in any order, so this change is fairly cosmetic.

Signed-off-by Ed Cashin <[email protected]>
---
 drivers/block/aoe/aoechr.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
drivers/block/aoe/aoechr.c +2 -2
index 3557f0d..acdd0ad 100644
@@ -96,13 +96,14 @@ revalidate(const char __user *str, size_t size)
 		return -EINVAL;
 	spin_lock_irqsave(&d->lock, flags);
 	aoecmd_cleanslate(d);
+	aoecmd_cfg(major, minor);
 loop:
 	skb = aoecmd_ata_id(d);
 	spin_unlock_irqrestore(&d->lock, flags);
 	/* try again if we are able to sleep a bit,
 	 * otherwise give up this revalidation
 	 */
-	if (!skb && !msleep_interruptible(200)) {
+	if (!skb && !msleep_interruptible(250)) {
 		spin_lock_irqsave(&d->lock, flags);
 		goto loop;
 	}

@@ -113,7 +114,6 @@ loop:
 		__skb_queue_tail(&queue, skb);
 		aoenet_xmit(&queue);
 	}
-	aoecmd_cfg(major, minor);
 	return 0;
 }
Signature · 1 line
1.7.2.5
author
#9 lore raw

PATCH 8/14 aoe: disallow unsupported AoE minor addresses

In reply to Ed Cashin

A guard is inserted to prevent AoE minor addresses (slot addresses) higher than 15 to be used, as they are not yet supported by the driver.

There is a change coming that will allow the aoe driver to overcome this limit by using system device minor numbers dynamically, but until then, this guard prevents unexpected targets from being used by the driver when AoE targets with high minor numbers are on the AoE network.

Signed-off-by Ed Cashin <[email protected]>
---
 drivers/block/aoe/aoecmd.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)
drivers/block/aoe/aoecmd.c +7 -0
index 7f9cc44..61cc1cf 100644
@@ -1359,6 +1359,13 @@ aoecmd_cfg_rsp(struct sk_buff *skb)
 			"Check shelf dip switches.\n");
 		return;
 	}
+	if (h->minor >= NPERSHELF) {
+		pr_err("aoe: e%ld.%d %s, %d\n",
+			aoemajor, h->minor,
+			"slot number larger than the maximum",
+			NPERSHELF-1);
+		return;
+	}
 
 	sysminor = SYSMINOR(aoemajor, h->minor);
 	if (sysminor * AOE_PARTITIONS + AOE_PARTITIONS > MINORMASK) {
Signature · 1 line
1.7.2.5
author
#10 lore raw

PATCH 9/14 aoe: associate frames with the AoE storage target

In reply to Ed Cashin

In the driver code, "target" and aoetgt refer to a particular remote interface on the AoE storage target. The latter is identified by its AoE major and minor addresses. Commands that are being sent to an AoE storage target {major, minor} can be sent or retransmitted to any of the remote MAC addresses associated with the AoE storage target.

That is, frames are naturally associated with not an aoetgt (AoE major, AoE minor, remote MAC address) but an aoedev (AoE major, AoE minor). Making the code reflect that reality simplifies the driver, especially when the path to a remote MAC address becomes unusable.

Signed-off-by Ed Cashin <[email protected]>
---
 drivers/block/aoe/aoe.h    |    8 +++---
 drivers/block/aoe/aoecmd.c |   65 +++++++++++++++++++-------------------------
 drivers/block/aoe/aoedev.c |   30 +++++++++++---------
 3 files changed, 49 insertions(+), 54 deletions(-)
drivers/block/aoe/aoe.h +4 -4
index d17b727..dab7258 100644
@@ -91,7 +91,7 @@ enum {
 	NTARGETS = 8,
 	NAOEIFS = 8,
 	NSKBPOOLMAX = 256,
-	NFACTIVE = 17,
+	NFACTIVE = 61,
 
 	TIMERTICK = HZ / 10,
 	MINTIMER = HZ >> 2,

@@ -132,14 +132,11 @@ struct aoetgt {
 	unsigned char addr[6];
 	ushort nframes;
 	struct aoedev *d;			/* parent device I belong to */
-	struct list_head factive[NFACTIVE];	/* hash of active frames */
 	struct list_head ffree;			/* list of free frames */
 	struct aoeif ifs[NAOEIFS];
 	struct aoeif *ifp;	/* current aoeif in use */
 	ushort nout;
 	ushort maxout;
-	u16 lasttag;		/* last tag sent */
-	u16 useme;
 	ulong falloc;
 	ulong lastwadj;		/* last window adjustment */
 	int minbcnt;

@@ -156,6 +153,8 @@ struct aoedev {
 	u16 rttavg;		/* round trip average of requests/responses */
 	u16 mintimer;
 	u16 fw_ver;		/* version of blade's firmware */
+	u16 lasttag;		/* last tag sent */
+	u16 useme;
 	ulong ref;
 	struct work_struct work;/* disk create work struct */
 	struct gendisk *gd;

@@ -172,6 +171,7 @@ struct aoedev {
 		struct request *rq;
 	} ip;
 	ulong maxbcnt;
+	struct list_head factive[NFACTIVE];	/* hash of active frames */
 	struct aoetgt *targets[NTARGETS];
 	struct aoetgt **tgt;	/* target in use when working */
 	struct aoetgt *htgt;	/* target needing rexmit assistance */
drivers/block/aoe/aoecmd.c +28 -37

152 lines not on this page · raw message

drivers/block/aoe/aoedev.c +17 -13
index 635dc98..3968fe6 100644
@@ -103,22 +103,23 @@ aoedev_downdev(struct aoedev *d)
 
 	d->flags &= ~DEVFL_UP;
 
-	/* clean out active buffers on all targets */
+	/* clean out active buffers */
+	for (i = 0; i < NFACTIVE; i++) {
+		head = &d->factive[i];
+		list_for_each_safe(pos, nx, head) {
+			f = list_entry(pos, struct frame, head);
+			list_del(pos);
+			if (f->buf) {
+				f->buf->nframesout--;
+				aoe_failbuf(d, f->buf);
+			}
+			aoe_freetframe(f);
+		}
+	}
+	/* reset window dressings */
 	tt = d->targets;
 	te = tt + NTARGETS;
 	for (; tt < te && (t = *tt); tt++) {
-		for (i = 0; i < NFACTIVE; i++) {
-			head = &t->factive[i];
-			list_for_each_safe(pos, nx, head) {
-				list_del(pos);
-				f = list_entry(pos, struct frame, head);
-				if (f->buf) {
-					f->buf->nframesout--;
-					aoe_failbuf(d, f->buf);
-				}
-				aoe_freetframe(f);
-			}
-		}
 		t->maxout = t->nframes;
 		t->nout = 0;
 	}

@@ -250,6 +251,7 @@ struct aoedev *
 aoedev_by_sysminor_m(ulong sysminor)
 {
 	struct aoedev *d;
+	int i;
 	ulong flags;
 
 	spin_lock_irqsave(&devlist_lock, flags);

@@ -275,6 +277,8 @@ aoedev_by_sysminor_m(ulong sysminor)
 	d->bufpool = NULL;	/* defer to aoeblk_gdalloc */
 	d->tgt = d->targets;
 	d->ref = 1;
+	for (i = 0; i < NFACTIVE; i++)
+		INIT_LIST_HEAD(&d->factive[i]);
 	d->sysminor = sysminor;
 	d->aoemajor = AOEMAJOR(sysminor);
 	d->aoeminor = AOEMINOR(sysminor);
Signature · 1 line
1.7.2.5
author
#11 lore raw

PATCH 10/14 aoe: increase net_device reference count while using it

In reply to Ed Cashin

This change eliminates the danger that the user could rmmod the driver for a network interface that is being used for AoE by the aoe driver.

Signed-off-by Ed Cashin <[email protected]>
---
 drivers/block/aoe/aoecmd.c |    4 ++++
 drivers/block/aoe/aoedev.c |    7 +++++++
 2 files changed, 11 insertions(+), 0 deletions(-)
drivers/block/aoe/aoecmd.c +4 -0
index e39d815..d2de679 100644
@@ -493,12 +493,15 @@ static void
 ejectif(struct aoetgt *t, struct aoeif *ifp)
 {
 	struct aoeif *e;
+	struct net_device *nd;
 	ulong n;
 
+	nd = ifp->nd;
 	e = t->ifs + NAOEIFS - 1;
 	n = (e - ifp) * sizeof *ifp;
 	memmove(ifp, ifp+1, n);
 	e->nd = NULL;
+	dev_put(nd);
 }
 
 static int

@@ -1317,6 +1320,7 @@ setifbcnt(struct aoetgt *t, struct net_device *nd, int bcnt)
 			pr_err("aoe: device setifbcnt failure; too many interfaces.\n");
 			return;
 		}
+		dev_hold(nd);
 		p->nd = nd;
 		p->bcnt = bcnt;
 	}
drivers/block/aoe/aoedev.c +7 -0
index 3968fe6..6be7b38 100644
@@ -295,6 +295,13 @@ freetgt(struct aoedev *d, struct aoetgt *t)
 {
 	struct frame *f;
 	struct list_head *pos, *nx, *head;
+	struct aoeif *ifp;
+
+	for (ifp = t->ifs; ifp < &t->ifs[NAOEIFS]; ++ifp) {
+		if (!ifp->nd)
+			break;
+		dev_put(ifp->nd);
+	}
 
 	head = &t->ffree;
 	list_for_each_safe(pos, nx, head) {
Signature · 1 line
1.7.2.5
author
#12 lore raw

PATCH 11/14 aoe: remove unused code and add cosmetic improvements

In reply to Ed Cashin

This change removes some unused code and attempts to increase code consistency.

Signed-off-by Ed Cashin <[email protected]>
---
 drivers/block/aoe/aoe.h    |   10 +++-------
 drivers/block/aoe/aoechr.c |    1 +
 drivers/block/aoe/aoecmd.c |   13 ++++---------
 drivers/block/aoe/aoenet.c |    3 ++-
 4 files changed, 10 insertions(+), 17 deletions(-)
drivers/block/aoe/aoe.h +3 -7
index dab7258..eb41fc5 100644
@@ -75,18 +75,14 @@ enum {
 	DEVFL_UP = 1,	/* device is installed in system and ready for AoE->ATA commands */
 	DEVFL_TKILL = (1<<1),	/* flag for timer to know when to kill self */
 	DEVFL_EXT = (1<<2),	/* device accepts lba48 commands */
-	DEVFL_CLOSEWAIT = (1<<3), /* device is waiting for all closes to revalidate */
-	DEVFL_GDALLOC = (1<<4),	/* need to alloc gendisk */
-	DEVFL_KICKME = (1<<5),	/* slow polling network card catch */
-	DEVFL_NEWSIZE = (1<<6),	/* need to update dev size in block layer */
-
-	BUFFL_FAIL = 1,
+	DEVFL_GDALLOC = (1<<3),	/* need to alloc gendisk */
+	DEVFL_KICKME = (1<<4),	/* slow polling network card catch */
+	DEVFL_NEWSIZE = (1<<5),	/* need to update dev size in block layer */
 };
 
 enum {
 	DEFAULTBCNT = 2 * 512,	/* 2 sectors */
 	NPERSHELF = 16,		/* number of slots per shelf address */
-	FREETAG = -1,
 	MIN_BUFS = 16,
 	NTARGETS = 8,
 	NAOEIFS = 8,
drivers/block/aoe/aoechr.c +1 -0
index acdd0ad..723e604 100644
@@ -174,6 +174,7 @@ aoechr_write(struct file *filp, const char __user *buf, size_t cnt, loff_t *offp
 		break;
 	case MINOR_FLUSH:
 		ret = aoedev_flush(buf, cnt);
+		break;
 	}
 	if (ret == 0)
 		ret = cnt;
drivers/block/aoe/aoecmd.c +4 -9
index d2de679..dd5d898 100644
@@ -283,7 +283,6 @@ aoecmd_ata_rw(struct aoedev *d)
 	struct aoe_hdr *h;
 	struct aoe_atahdr *ah;
 	struct buf *buf;
-	struct bio_vec *bv;
 	struct aoetgt *t;
 	struct sk_buff *skb;
 	struct sk_buff_head queue;

@@ -300,7 +299,6 @@ aoecmd_ata_rw(struct aoedev *d)
 	if (f == NULL)
 		return 0;
 	t = *d->tgt;
-	bv = buf->bv;
 	bcnt = d->maxbcnt;
 	if (bcnt == 0)
 		bcnt = DEFAULTBCNT;

@@ -787,28 +785,25 @@ void
 aoecmd_sleepwork(struct work_struct *work)
 {
 	struct aoedev *d = container_of(work, struct aoedev, work);
+	struct block_device *bd;
+	u64 ssize;
 
 	if (d->flags & DEVFL_GDALLOC)
 		aoeblk_gdalloc(d);
 
 	if (d->flags & DEVFL_NEWSIZE) {
-		struct block_device *bd;
-		unsigned long flags;
-		u64 ssize;
-
 		ssize = get_capacity(d->gd);
 		bd = bdget_disk(d->gd, 0);
-
 		if (bd) {
 			mutex_lock(&bd->bd_inode->i_mutex);
 			i_size_write(bd->bd_inode, (loff_t)ssize<<9);
 			mutex_unlock(&bd->bd_inode->i_mutex);
 			bdput(bd);
 		}
-		spin_lock_irqsave(&d->lock, flags);
+		spin_lock_irq(&d->lock);
 		d->flags |= DEVFL_UP;
 		d->flags &= ~DEVFL_NEWSIZE;
-		spin_unlock_irqrestore(&d->lock, flags);
+		spin_unlock_irq(&d->lock);
 	}
 }
drivers/block/aoe/aoenet.c +2 -1
index 5f43710..3c923e5 100644
@@ -175,7 +175,8 @@ aoenet_rcv(struct sk_buff *skb, struct net_device *ifp, struct packet_type *pt,
 	default:
 		if (h->cmd >= AOECMD_VEND_MIN)
 			break;	/* don't complain about vendor commands */
-		printk(KERN_INFO "aoe: unknown cmd %d\n", h->cmd);
+		pr_info("aoe: unknown AoE command type 0x%02x\n", h->cmd);
+		break;
 	}
 
 	if (!skb)
Signature · 1 line
1.7.2.5
author
#13 lore raw

PATCH 12/14 aoe: update internal version number to 49

In reply to Ed Cashin

The internal version number of the aoe driver appears in a console message when the driver loads and is usually obtained by the user with the userland aoe-version tool, part of the aoetools.[1]

Although this patchset includes bugfixes backported from higher-numbered versions published on the coraid.com website, it is a form of version 49.

1. http://aoetools.sourceforge.net/

Signed-off-by Ed Cashin <[email protected]>
---
 drivers/block/aoe/aoe.h |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
drivers/block/aoe/aoe.h +1 -1
index eb41fc5..32aede9 100644
@@ -1,5 +1,5 @@
 /* Copyright (c) 2007 Coraid, Inc.  See COPYING for GPL terms. */
-#define VERSION "47"
+#define VERSION "49"
 #define AOE_MAJOR 152
 #define DEVICE_NAME "aoe"
Signature · 1 line
1.7.2.5
author
#14 lore raw

PATCH 13/14 aoe: update copyright year in touched files

In reply to Ed Cashin
Signed-off-by Ed Cashin <[email protected]>
---
 drivers/block/aoe/aoe.h     |    2 +-
 drivers/block/aoe/aoeblk.c  |    2 +-
 drivers/block/aoe/aoechr.c  |    2 +-
 drivers/block/aoe/aoecmd.c  |    2 +-
 drivers/block/aoe/aoedev.c  |    2 +-
 drivers/block/aoe/aoemain.c |    2 +-
 drivers/block/aoe/aoenet.c  |    2 +-
 7 files changed, 7 insertions(+), 7 deletions(-)
drivers/block/aoe/aoe.h +1 -1
index 32aede9..27d0a21 100644
@@ -1,4 +1,4 @@
-/* Copyright (c) 2007 Coraid, Inc.  See COPYING for GPL terms. */
+/* Copyright (c) 2012 Coraid, Inc.  See COPYING for GPL terms. */
 #define VERSION "49"
 #define AOE_MAJOR 152
 #define DEVICE_NAME "aoe"
drivers/block/aoe/aoeblk.c +1 -1
index 7ec4b8f..83160ab 100644
@@ -1,4 +1,4 @@
-/* Copyright (c) 2007 Coraid, Inc.  See COPYING for GPL terms. */
+/* Copyright (c) 2012 Coraid, Inc.  See COPYING for GPL terms. */
 /*
  * aoeblk.c
  * block device routines
drivers/block/aoe/aoechr.c +1 -1
index 723e604..deb30c1 100644
@@ -1,4 +1,4 @@
-/* Copyright (c) 2007 Coraid, Inc.  See COPYING for GPL terms. */
+/* Copyright (c) 2012 Coraid, Inc.  See COPYING for GPL terms. */
 /*
  * aoechr.c
  * AoE character device driver
drivers/block/aoe/aoecmd.c +1 -1
index dd5d898..5461faa 100644
@@ -1,4 +1,4 @@
-/* Copyright (c) 2007 Coraid, Inc.  See COPYING for GPL terms. */
+/* Copyright (c) 2012 Coraid, Inc.  See COPYING for GPL terms. */
 /*
  * aoecmd.c
  * Filesystem request handling methods
drivers/block/aoe/aoedev.c +1 -1
index 6be7b38..ccaecff 100644
@@ -1,4 +1,4 @@
-/* Copyright (c) 2007 Coraid, Inc.  See COPYING for GPL terms. */
+/* Copyright (c) 2012 Coraid, Inc.  See COPYING for GPL terms. */
 /*
  * aoedev.c
  * AoE device utility functions; maintains device list.
drivers/block/aoe/aoemain.c +1 -1
index 6fc4b05..04793c2 100644
@@ -1,4 +1,4 @@
-/* Copyright (c) 2007 Coraid, Inc.  See COPYING for GPL terms. */
+/* Copyright (c) 2012 Coraid, Inc.  See COPYING for GPL terms. */
 /*
  * aoemain.c
  * Module initialization routines, discover timer
drivers/block/aoe/aoenet.c +1 -1
index 3c923e5..162c647 100644
@@ -1,4 +1,4 @@
-/* Copyright (c) 2007 Coraid, Inc.  See COPYING for GPL terms. */
+/* Copyright (c) 2012 Coraid, Inc.  See COPYING for GPL terms. */
 /*
  * aoenet.c
  * Ethernet portion of AoE driver
Signature · 1 line
1.7.2.5
author
#15 lore raw

PATCH 14/14 aoe: update documentation with new URL and VM settings reference

In reply to Ed Cashin

The old area has a new URL. Also, now that the driver can perform better, it is worth mentioning the VM settings that help aoe to sink dirty pages out early, avoiding unecessary memory pressure when much I/O is going on.

Signed-off-by Ed Cashin <[email protected]>
---
 Documentation/aoe/aoe.txt |    9 ++++++---
 MAINTAINERS               |    2 +-
 2 files changed, 7 insertions(+), 4 deletions(-)
Documentation/aoe/aoe.txt +6 -3
index 5f5aa16..b3e4756 100644
@@ -1,8 +1,11 @@
-The EtherDrive (R) HOWTO for users of 2.6 kernels is found at ...
+The EtherDrive (R) HOWTO for 2.6 and 3.x kernels is found at ...
 
-  http://www.coraid.com/SUPPORT/EtherDrive-HBA  
+  http://support.coraid.com/support/linux/EtherDrive-2.6-HOWTO.html
 
-  It has many tips and hints!
+It has many tips and hints!  Please see, especially, recommended
+tunings for virtual memory:
+
+  http://support.coraid.com/support/linux/EtherDrive-2.6-HOWTO-5.html#ss5.19
 
 The aoetools are userland programs that are designed to work with this
 driver.  The aoetools are on sourceforge.
MAINTAINERS +1 -1
index fdc0119..917b0d8 100644
@@ -1250,7 +1250,7 @@ F:	include/linux/i2c/at24.h
 
 ATA OVER ETHERNET (AOE) DRIVER
 M:	"Ed L. Cashin" <[email protected]>
-W:	http://www.coraid.com/support/linux
+W:	http://support.coraid.com/support/linux
 S:	Supported
 F:	Documentation/aoe/
 F:	drivers/block/aoe/
Signature · 1 line
1.7.2.5