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-rw-r--r--drivers/block/aoe/aoe.h16
-rw-r--r--drivers/block/aoe/aoecmd.c173
-rw-r--r--drivers/block/aoe/aoedev.c6
3 files changed, 121 insertions, 74 deletions
diff --git a/drivers/block/aoe/aoe.h b/drivers/block/aoe/aoe.h
index f6e0c03fe7b..9e884acd75f 100644
--- a/drivers/block/aoe/aoe.h
+++ b/drivers/block/aoe/aoe.h
@@ -86,8 +86,11 @@ enum {
NFACTIVE = 61,
TIMERTICK = HZ / 10,
- MINTIMER = HZ >> 2,
+ RTTSCALE = 8,
+ RTTDSCALE = 3,
MAXTIMER = HZ << 1,
+ RTTAVG_INIT = HZ / 4 << RTTSCALE,
+ RTTDEV_INIT = RTTAVG_INIT / 4,
};
struct buf {
@@ -127,10 +130,11 @@ struct aoetgt {
struct list_head ffree; /* list of free frames */
struct aoeif ifs[NAOEIFS];
struct aoeif *ifp; /* current aoeif in use */
- ushort nout;
+ ushort nout; /* value of nout when skb was sent */
ushort maxout; /* current value for max outstanding */
+ ushort next_cwnd; /* incr maxout after decrementing to zero */
+ ushort ssthresh; /* slow start threshold */
ulong falloc; /* number of allocated frames */
- ulong lastwadj; /* last window adjustment */
int minbcnt;
int wpkts, rpkts;
};
@@ -142,8 +146,8 @@ struct aoedev {
u16 aoeminor;
u16 flags;
u16 nopen; /* (bd_openers isn't available without sleeping) */
- u16 rttavg; /* round trip average of requests/responses */
- u16 mintimer;
+ u16 rttavg; /* scaled AoE round trip time average */
+ u16 rttdev; /* scaled round trip time mean deviation */
u16 fw_ver; /* version of blade's firmware */
u16 lasttag; /* last tag sent */
u16 useme;
@@ -164,6 +168,7 @@ struct aoedev {
} ip;
ulong maxbcnt;
struct list_head factive[NFACTIVE]; /* hash of active frames */
+ struct list_head rexmitq; /* deferred retransmissions */
struct aoetgt *targets[NTARGETS];
struct aoetgt **tgt; /* target in use when working */
struct aoetgt *htgt; /* target needing rexmit assistance */
@@ -196,6 +201,7 @@ void aoecmd_cfg(ushort aoemajor, unsigned char aoeminor);
struct sk_buff *aoecmd_ata_rsp(struct sk_buff *);
void aoecmd_cfg_rsp(struct sk_buff *);
void aoecmd_sleepwork(struct work_struct *);
+void aoecmd_wreset(struct aoetgt *t);
void aoecmd_cleanslate(struct aoedev *);
void aoecmd_exit(void);
int aoecmd_init(void);
diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index c4ff70b61e7..f849fa2471c 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -59,6 +59,23 @@ new_skb(ulong len)
}
static struct frame *
+getframe_deferred(struct aoedev *d, u32 tag)
+{
+ struct list_head *head, *pos, *nx;
+ struct frame *f;
+
+ head = &d->rexmitq;
+ list_for_each_safe(pos, nx, head) {
+ f = list_entry(pos, struct frame, head);
+ if (f->tag == tag) {
+ list_del(pos);
+ return f;
+ }
+ }
+ return NULL;
+}
+
+static struct frame *
getframe(struct aoedev *d, u32 tag)
{
struct frame *f;
@@ -553,10 +570,29 @@ sthtith(struct aoedev *d)
}
static void
+rexmit_deferred(struct aoedev *d)
+{
+ struct aoetgt *t;
+ struct frame *f;
+ struct list_head *pos, *nx, *head;
+
+ head = &d->rexmitq;
+ list_for_each_safe(pos, nx, head) {
+ f = list_entry(pos, struct frame, head);
+ t = f->t;
+ if (t->nout >= t->maxout)
+ continue;
+ list_del(pos);
+ t->nout++;
+ resend(d, f);
+ }
+}
+
+static void
rexmit_timer(ulong vp)
{
struct aoedev *d;
- struct aoetgt *t, **tt, **te;
+ struct aoetgt *t;
struct aoeif *ifp;
struct frame *f;
struct list_head *head, *pos, *nx;
@@ -567,9 +603,11 @@ rexmit_timer(ulong vp)
d = (struct aoedev *) vp;
- /* timeout is always ~150% of the moving average */
- timeout = d->rttavg;
- timeout += timeout >> 1;
+ /* timeout based on observed timings and variations */
+ timeout = 2 * d->rttavg >> RTTSCALE;
+ timeout += 8 * d->rttdev >> RTTDSCALE;
+ if (timeout == 0)
+ timeout = 1;
spin_lock_irqsave(&d->lock, flags);
@@ -589,29 +627,12 @@ rexmit_timer(ulong vp)
list_move_tail(pos, &flist);
}
}
- /* window check */
- tt = d->targets;
- te = tt + d->ntargets;
- for (; tt < te && (t = *tt); tt++) {
- if (t->nout == t->maxout
- && t->maxout < t->nframes
- && (jiffies - t->lastwadj)/HZ > 10) {
- t->maxout++;
- t->lastwadj = jiffies;
- }
- }
-
- if (!list_empty(&flist)) { /* retransmissions necessary */
- n = d->rttavg <<= 1;
- if (n > MAXTIMER)
- d->rttavg = MAXTIMER;
- }
/* process expired frames */
while (!list_empty(&flist)) {
pos = flist.next;
f = list_entry(pos, struct frame, head);
- n = f->waited += timeout;
+ n = f->waited += tsince(f->tag);
n /= HZ;
if (n > aoe_deadsecs) {
/* Waited too long. Device failure.
@@ -620,18 +641,16 @@ rexmit_timer(ulong vp)
*/
list_splice(&flist, &d->factive[0]);
aoedev_downdev(d);
- break;
+ goto out;
}
- list_del(pos);
t = f->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--;
- t->lastwadj = jiffies;
+ if (t->maxout != 1) {
+ t->ssthresh = t->maxout / 2;
+ t->maxout = 1;
}
ifp = getif(t, f->skb->dev);
@@ -640,9 +659,12 @@ rexmit_timer(ulong vp)
ejectif(t, ifp);
ifp = NULL;
}
- resend(d, f);
+ list_move_tail(pos, &d->rexmitq);
+ t->nout--;
}
+ rexmit_deferred(d);
+out:
if ((d->flags & DEVFL_KICKME || d->htgt) && d->blkq) {
d->flags &= ~DEVFL_KICKME;
d->blkq->request_fn(d->blkq);
@@ -766,6 +788,7 @@ aoecmd_work(struct aoedev *d)
{
if (d->htgt && !sthtith(d))
return;
+ rexmit_deferred(d);
while (aoecmd_ata_rw(d))
;
}
@@ -868,26 +891,28 @@ ataid_complete(struct aoedev *d, struct aoetgt *t, unsigned char *id)
}
static void
-calc_rttavg(struct aoedev *d, int rtt)
+calc_rttavg(struct aoedev *d, struct aoetgt *t, int rtt)
{
register long n;
n = rtt;
- if (n < 0) {
- n = -rtt;
- if (n < MINTIMER)
- n = MINTIMER;
- else if (n > MAXTIMER)
- n = MAXTIMER;
- d->mintimer += (n - d->mintimer) >> 1;
- } else if (n < d->mintimer)
- n = d->mintimer;
- else if (n > MAXTIMER)
- n = MAXTIMER;
-
- /* g == .25; cf. Congestion Avoidance and Control, Jacobson & Karels; 1988 */
- n -= d->rttavg;
- d->rttavg += n >> 2;
+
+ /* cf. Congestion Avoidance and Control, Jacobson & Karels, 1988 */
+ n -= d->rttavg >> RTTSCALE;
+ d->rttavg += n;
+ if (n < 0)
+ n = -n;
+ n -= d->rttdev >> RTTDSCALE;
+ d->rttdev += n;
+
+ if (!t || t->maxout >= t->nframes)
+ return;
+ if (t->maxout < t->ssthresh)
+ t->maxout += 1;
+ else if (t->nout == t->maxout && t->next_cwnd-- == 0) {
+ t->maxout += 1;
+ t->next_cwnd = t->maxout;
+ }
}
static struct aoetgt *
@@ -1147,7 +1172,6 @@ aoecmd_ata_rsp(struct sk_buff *skb)
struct aoedev *d;
struct aoe_hdr *h;
struct frame *f;
- struct aoetgt *t;
u32 n;
ulong flags;
char ebuf[128];
@@ -1168,23 +1192,28 @@ aoecmd_ata_rsp(struct sk_buff *skb)
n = be32_to_cpu(get_unaligned(&h->tag));
f = getframe(d, n);
- if (f == NULL) {
- calc_rttavg(d, -tsince(n));
- spin_unlock_irqrestore(&d->lock, flags);
- aoedev_put(d);
- snprintf(ebuf, sizeof ebuf,
- "%15s e%d.%d tag=%08x@%08lx\n",
- "unexpected rsp",
- get_unaligned_be16(&h->major),
- h->minor,
- get_unaligned_be32(&h->tag),
- jiffies);
- aoechr_error(ebuf);
- return skb;
+ if (f) {
+ calc_rttavg(d, f->t, tsince(n));
+ f->t->nout--;
+ } else {
+ f = getframe_deferred(d, n);
+ if (f) {
+ calc_rttavg(d, NULL, tsince(n));
+ } else {
+ calc_rttavg(d, NULL, tsince(n));
+ spin_unlock_irqrestore(&d->lock, flags);
+ aoedev_put(d);
+ snprintf(ebuf, sizeof(ebuf),
+ "%15s e%d.%d tag=%08x@%08lx\n",
+ "unexpected rsp",
+ get_unaligned_be16(&h->major),
+ h->minor,
+ get_unaligned_be32(&h->tag),
+ jiffies);
+ aoechr_error(ebuf);
+ return skb;
+ }
}
- t = f->t;
- calc_rttavg(d, tsince(f->tag));
- t->nout--;
aoecmd_work(d);
spin_unlock_irqrestore(&d->lock, flags);
@@ -1241,7 +1270,8 @@ aoecmd_ata_id(struct aoedev *d)
skb->dev = t->ifp->nd;
- d->rttavg = MAXTIMER;
+ d->rttavg = RTTAVG_INIT;
+ d->rttdev = RTTDEV_INIT;
d->timer.function = rexmit_timer;
return skb_clone(skb, GFP_ATOMIC);
@@ -1273,7 +1303,7 @@ addtgt(struct aoedev *d, char *addr, ulong nframes)
t->d = d;
memcpy(t->addr, addr, sizeof t->addr);
t->ifp = t->ifs;
- t->maxout = t->nframes;
+ aoecmd_wreset(t);
INIT_LIST_HEAD(&t->ffree);
return *tt = t;
}
@@ -1382,7 +1412,7 @@ aoecmd_cfg_rsp(struct sk_buff *skb)
if (t) {
t->nframes = n;
if (n < t->maxout)
- t->maxout = n;
+ aoecmd_wreset(t);
} else {
t = addtgt(d, h->src, n);
if (!t)
@@ -1412,17 +1442,26 @@ bail:
}
void
+aoecmd_wreset(struct aoetgt *t)
+{
+ t->maxout = 1;
+ t->ssthresh = t->nframes / 2;
+ t->next_cwnd = t->nframes;
+}
+
+void
aoecmd_cleanslate(struct aoedev *d)
{
struct aoetgt **t, **te;
- d->mintimer = MINTIMER;
+ d->rttavg = RTTAVG_INIT;
+ d->rttdev = RTTDEV_INIT;
d->maxbcnt = 0;
t = d->targets;
te = t + NTARGETS;
for (; t < te && *t; t++)
- (*t)->maxout = (*t)->nframes;
+ aoecmd_wreset(*t);
}
void
diff --git a/drivers/block/aoe/aoedev.c b/drivers/block/aoe/aoedev.c
index 63b26609400..3c3aef20810 100644
--- a/drivers/block/aoe/aoedev.c
+++ b/drivers/block/aoe/aoedev.c
@@ -198,7 +198,7 @@ aoedev_downdev(struct aoedev *d)
tt = d->targets;
te = tt + NTARGETS;
for (; tt < te && (t = *tt); tt++) {
- t->maxout = t->nframes;
+ aoecmd_wreset(t);
t->nout = 0;
}
@@ -391,10 +391,12 @@ aoedev_by_aoeaddr(ulong maj, int min, int do_alloc)
d->ref = 1;
for (i = 0; i < NFACTIVE; i++)
INIT_LIST_HEAD(&d->factive[i]);
+ INIT_LIST_HEAD(&d->rexmitq);
d->sysminor = sysminor;
d->aoemajor = maj;
d->aoeminor = min;
- d->mintimer = MINTIMER;
+ d->rttavg = RTTAVG_INIT;
+ d->rttdev = RTTDEV_INIT;
d->next = devlist;
devlist = d;
out:
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-25 04:27:07 +0000