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Atheros SuperG bug fixes, as part of hunting down kern/174283.

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The stageqdepth (global, over all staging queues) was being kept
incorrectly.  It was being incremented whenever things were added,
but only decremented during a flush.  During active fast frames activity
it wasn't being decremented, resulting in it always having a non-zero
value during normal fast-frames operation.

It was only used when checking if the aging queue should be checked;
we may as well just defer to each of those staging queue counters (which
look correct, thankfully.)

Whilst I'm here, add locking assertions in the staging queue add/remove
functions.  The current crash shows that the staging queue has one frame,
but only has a tail pointer set (the head pointer being set to NULL.)
I'd like to grab a few more crashes where these locking assertions are
in place so I can narrow down the issue between "somehow locking is
messed up and things are racy" and "the stage queue head/tail pointer
manipulation logic is subtly wrong."

Tested:

* AR5416 STA, AR5413 AP; with FastFrames enabled in the AR5416 HAL.

PR:		kern/174283
This commit is contained in:
Adrian Chadd 2012-12-09 19:20:28 +00:00
parent 7a50e936c0
commit b3c69eef25
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=244051
2 changed files with 12 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
sys/net80211/ieee80211_superg.c
View File

@ -560,7 +560,6 @@ void
ieee80211_ff_age(struct ieee80211com *ic, struct ieee80211_stageq *sq,
int quanta)
{
struct ieee80211_superg *sg = ic->ic_superg;
struct mbuf *m, *head;
struct ieee80211_node *ni;
struct ieee80211_tx_ampdu *tap;
@ -582,7 +581,6 @@ ieee80211_ff_age(struct ieee80211com *ic, struct ieee80211_stageq *sq,
sq->head = m->m_nextpkt;
sq->depth--;
sg->ff_stageqdepth--;
}
if (m == NULL)
sq->tail = NULL;
@ -594,9 +592,12 @@ ieee80211_ff_age(struct ieee80211com *ic, struct ieee80211_stageq *sq,
}
static void
stageq_add(struct ieee80211_stageq *sq, struct mbuf *m)
stageq_add(struct ieee80211com *ic, struct ieee80211_stageq *sq, struct mbuf *m)
{
int age = ieee80211_ffagemax;
IEEE80211_LOCK_ASSERT(ic);
if (sq->tail != NULL) {
sq->tail->m_nextpkt = m;
age -= M_AGE_GET(sq->head);
@ -610,10 +611,12 @@ stageq_add(struct ieee80211_stageq *sq, struct mbuf *m)
}
static void
stageq_remove(struct ieee80211_stageq *sq, struct mbuf *mstaged)
stageq_remove(struct ieee80211com *ic, struct ieee80211_stageq *sq, struct mbuf *mstaged)
{
struct mbuf *m, *mprev;
IEEE80211_LOCK_ASSERT(ic);
mprev = NULL;
for (m = sq->head; m != NULL; m = m->m_nextpkt) {
if (m == mstaged) {
@ -725,7 +728,7 @@ ieee80211_ff_check(struct ieee80211_node *ni, struct mbuf *m)
tap->txa_private = NULL;
if (mstaged != NULL)
stageq_remove(sq, mstaged);
stageq_remove(ic, sq, mstaged);
IEEE80211_UNLOCK(ic);
if (mstaged != NULL) {
@ -745,7 +748,7 @@ ieee80211_ff_check(struct ieee80211_node *ni, struct mbuf *m)
*/
if (mstaged != NULL) {
tap->txa_private = NULL;
stageq_remove(sq, mstaged);
stageq_remove(ic, sq, mstaged);
IEEE80211_UNLOCK(ic);
IEEE80211_NOTE(vap, IEEE80211_MSG_SUPERG, ni,
@ -766,8 +769,7 @@ ieee80211_ff_check(struct ieee80211_node *ni, struct mbuf *m)
("txa_private %p", tap->txa_private));
tap->txa_private = m;
stageq_add(sq, m);
sg->ff_stageqdepth++;
stageq_add(ic, sq, m);
IEEE80211_UNLOCK(ic);
IEEE80211_NOTE(vap, IEEE80211_MSG_SUPERG, ni,
@ -806,7 +808,7 @@ ieee80211_ff_node_cleanup(struct ieee80211_node *ni)
m = tap->txa_private;
if (m != NULL) {
tap->txa_private = NULL;
stageq_remove(&sg->ff_stageq[ac], m);
stageq_remove(ic, &sg->ff_stageq[ac], m);
m->m_nextpkt = head;
head = m;
}

3
sys/net80211/ieee80211_superg.h
View File

@ -66,7 +66,6 @@ struct ieee80211_stageq {
struct ieee80211_superg {
/* fast-frames staging q */
struct ieee80211_stageq ff_stageq[WME_NUM_AC];
int ff_stageqdepth; /* cumulative depth */
};
void ieee80211_superg_attach(struct ieee80211com *);
@ -109,7 +108,7 @@ ieee80211_ff_age_all(struct ieee80211com *ic, int quanta)
{
struct ieee80211_superg *sg = ic->ic_superg;
if (sg != NULL && sg->ff_stageqdepth) {
if (sg != NULL) {
if (sg->ff_stageq[WME_AC_VO].depth)
ieee80211_ff_age(ic, &sg->ff_stageq[WME_AC_VO], quanta);
if (sg->ff_stageq[WME_AC_VI].depth)