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Commit 33d61f24 authored by Alan Stern's avatar Alan Stern Committed by Greg Kroah-Hartman
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[PATCH] USB: UHCI: Get rid of excessive spinlocks 

This patch introduces a major simplification into the UHCI driver by
replacing its multiple spinlocks with a single one.  The protected area of
code is slightly larger and there's more possibilities for contention on
an SMP system, but I think that shouldn't be a problem.  Stephen Hemminger
has been kind enough to test this on his SMP computer and he hasn't
encountered any difficulties.
parent 2212df84
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Showing with 42 additions and 172 deletions
drivers/usb/host/uhci-debug.c
View file @ 33d61f24
...@@ -27,7 +27,7 @@ static inline void lprintk(char *buf) ...@@ -27,7 +27,7 @@ static inline void lprintk(char *buf)
p = strchr(buf, '\n'); p = strchr(buf, '\n');
if (p) if (p)
*p = 0; *p = 0;
printk("%s\n", buf); printk(KERN_DEBUG "%s\n", buf);
buf = p; buf = p;
if (buf) if (buf)
buf++; buf++;
...@@ -328,21 +328,17 @@ static int uhci_show_urbp(struct uhci_hcd *uhci, struct urb_priv *urbp, char *bu ...@@ -328,21 +328,17 @@ static int uhci_show_urbp(struct uhci_hcd *uhci, struct urb_priv *urbp, char *bu
//out += sprintf(out, "Inserttime=%lx ",urbp->inserttime); //out += sprintf(out, "Inserttime=%lx ",urbp->inserttime);
//out += sprintf(out, "FSBRtime=%lx ",urbp->fsbrtime); //out += sprintf(out, "FSBRtime=%lx ",urbp->fsbrtime);
spin_lock(&urbp->urb->lock);
count = 0; count = 0;
list_for_each(tmp, &urbp->td_list) list_for_each(tmp, &urbp->td_list)
count++; count++;
spin_unlock(&urbp->urb->lock);
out += sprintf(out, "TDs=%d ",count); out += sprintf(out, "TDs=%d ",count);
if (urbp->queued) if (urbp->queued)
out += sprintf(out, "queued\n"); out += sprintf(out, "queued\n");
else { else {
spin_lock(&uhci->frame_list_lock);
count = 0; count = 0;
list_for_each(tmp, &urbp->queue_list) list_for_each(tmp, &urbp->queue_list)
count++; count++;
spin_unlock(&uhci->frame_list_lock);
out += sprintf(out, "queued URBs=%d\n", count); out += sprintf(out, "queued URBs=%d\n", count);
} }
...@@ -352,12 +348,10 @@ static int uhci_show_urbp(struct uhci_hcd *uhci, struct urb_priv *urbp, char *bu ...@@ -352,12 +348,10 @@ static int uhci_show_urbp(struct uhci_hcd *uhci, struct urb_priv *urbp, char *bu
static int uhci_show_lists(struct uhci_hcd *uhci, char *buf, int len) static int uhci_show_lists(struct uhci_hcd *uhci, char *buf, int len)
{ {
char *out = buf; char *out = buf;
unsigned long flags;
struct list_head *head, *tmp; struct list_head *head, *tmp;
int count; int count;
out += sprintf(out, "Main list URBs:"); out += sprintf(out, "Main list URBs:");
spin_lock_irqsave(&uhci->urb_list_lock, flags);
if (list_empty(&uhci->urb_list)) if (list_empty(&uhci->urb_list))
out += sprintf(out, " Empty\n"); out += sprintf(out, " Empty\n");
else { else {
...@@ -373,10 +367,8 @@ static int uhci_show_lists(struct uhci_hcd *uhci, char *buf, int len) ...@@ -373,10 +367,8 @@ static int uhci_show_lists(struct uhci_hcd *uhci, char *buf, int len)
tmp = tmp->next; tmp = tmp->next;
} }
} }
spin_unlock_irqrestore(&uhci->urb_list_lock, flags);
out += sprintf(out, "Remove list URBs:"); out += sprintf(out, "Remove list URBs:");
spin_lock_irqsave(&uhci->urb_remove_list_lock, flags);
if (list_empty(&uhci->urb_remove_list)) if (list_empty(&uhci->urb_remove_list))
out += sprintf(out, " Empty\n"); out += sprintf(out, " Empty\n");
else { else {
...@@ -392,10 +384,8 @@ static int uhci_show_lists(struct uhci_hcd *uhci, char *buf, int len) ...@@ -392,10 +384,8 @@ static int uhci_show_lists(struct uhci_hcd *uhci, char *buf, int len)
tmp = tmp->next; tmp = tmp->next;
} }
} }
spin_unlock_irqrestore(&uhci->urb_remove_list_lock, flags);
out += sprintf(out, "Complete list URBs:"); out += sprintf(out, "Complete list URBs:");
spin_lock_irqsave(&uhci->complete_list_lock, flags);
if (list_empty(&uhci->complete_list)) if (list_empty(&uhci->complete_list))
out += sprintf(out, " Empty\n"); out += sprintf(out, " Empty\n");
else { else {
...@@ -411,7 +401,6 @@ static int uhci_show_lists(struct uhci_hcd *uhci, char *buf, int len) ...@@ -411,7 +401,6 @@ static int uhci_show_lists(struct uhci_hcd *uhci, char *buf, int len)
tmp = tmp->next; tmp = tmp->next;
} }
} }
spin_unlock_irqrestore(&uhci->complete_list_lock, flags);
return out - buf; return out - buf;
} }
...@@ -425,7 +414,7 @@ static int uhci_sprint_schedule(struct uhci_hcd *uhci, char *buf, int len) ...@@ -425,7 +414,7 @@ static int uhci_sprint_schedule(struct uhci_hcd *uhci, char *buf, int len)
struct uhci_td *td; struct uhci_td *td;
struct list_head *tmp, *head; struct list_head *tmp, *head;
spin_lock_irqsave(&uhci->frame_list_lock, flags); spin_lock_irqsave(&uhci->schedule_lock, flags);
out += sprintf(out, "HC status\n"); out += sprintf(out, "HC status\n");
out += uhci_show_status(uhci, out, len - (out - buf)); out += uhci_show_status(uhci, out, len - (out - buf));
...@@ -508,11 +497,11 @@ static int uhci_sprint_schedule(struct uhci_hcd *uhci, char *buf, int len) ...@@ -508,11 +497,11 @@ static int uhci_sprint_schedule(struct uhci_hcd *uhci, char *buf, int len)
} }
} }
spin_unlock_irqrestore(&uhci->frame_list_lock, flags);
if (debug > 2) if (debug > 2)
out += uhci_show_lists(uhci, out, len - (out - buf)); out += uhci_show_lists(uhci, out, len - (out - buf));
spin_unlock_irqrestore(&uhci->schedule_lock, flags);
return out - buf; return out - buf;
} }
...@@ -623,4 +612,3 @@ static struct file_operations uhci_proc_operations = { ...@@ -623,4 +612,3 @@ static struct file_operations uhci_proc_operations = {
.release = uhci_proc_release, .release = uhci_proc_release,
}; };
#endif #endif
drivers/usb/host/uhci-hcd.c
View file @ 33d61f24
...@@ -117,26 +117,18 @@ static void hc_state_transitions(struct uhci_hcd *uhci); ...@@ -117,26 +117,18 @@ static void hc_state_transitions(struct uhci_hcd *uhci);
*/ */
static inline void uhci_set_next_interrupt(struct uhci_hcd *uhci) static inline void uhci_set_next_interrupt(struct uhci_hcd *uhci)
{ {
unsigned long flags;
spin_lock_irqsave(&uhci->frame_list_lock, flags);
uhci->term_td->status |= cpu_to_le32(TD_CTRL_IOC); uhci->term_td->status |= cpu_to_le32(TD_CTRL_IOC);
spin_unlock_irqrestore(&uhci->frame_list_lock, flags);
} }
static inline void uhci_clear_next_interrupt(struct uhci_hcd *uhci) static inline void uhci_clear_next_interrupt(struct uhci_hcd *uhci)
{ {
spin_lock(&uhci->frame_list_lock);
uhci->term_td->status &= ~cpu_to_le32(TD_CTRL_IOC); uhci->term_td->status &= ~cpu_to_le32(TD_CTRL_IOC);
spin_unlock(&uhci->frame_list_lock);
} }
static inline void uhci_moveto_complete(struct uhci_hcd *uhci, static inline void uhci_moveto_complete(struct uhci_hcd *uhci,
struct urb_priv *urbp) struct urb_priv *urbp)
{ {
spin_lock(&uhci->complete_list_lock);
list_move_tail(&urbp->urb_list, &uhci->complete_list); list_move_tail(&urbp->urb_list, &uhci->complete_list);
spin_unlock(&uhci->complete_list_lock);
} }
static struct uhci_td *uhci_alloc_td(struct uhci_hcd *uhci, struct usb_device *dev) static struct uhci_td *uhci_alloc_td(struct uhci_hcd *uhci, struct usb_device *dev)
...@@ -178,12 +170,8 @@ static inline void uhci_fill_td(struct uhci_td *td, __u32 status, ...@@ -178,12 +170,8 @@ static inline void uhci_fill_td(struct uhci_td *td, __u32 status,
*/ */
static void uhci_insert_td_frame_list(struct uhci_hcd *uhci, struct uhci_td *td, unsigned framenum) static void uhci_insert_td_frame_list(struct uhci_hcd *uhci, struct uhci_td *td, unsigned framenum)
{ {
unsigned long flags;
framenum %= UHCI_NUMFRAMES; framenum %= UHCI_NUMFRAMES;
spin_lock_irqsave(&uhci->frame_list_lock, flags);
td->frame = framenum; td->frame = framenum;
/* Is there a TD already mapped there? */ /* Is there a TD already mapped there? */
...@@ -204,18 +192,13 @@ static void uhci_insert_td_frame_list(struct uhci_hcd *uhci, struct uhci_td *td, ...@@ -204,18 +192,13 @@ static void uhci_insert_td_frame_list(struct uhci_hcd *uhci, struct uhci_td *td,
uhci->fl->frame[framenum] = cpu_to_le32(td->dma_handle); uhci->fl->frame[framenum] = cpu_to_le32(td->dma_handle);
uhci->fl->frame_cpu[framenum] = td; uhci->fl->frame_cpu[framenum] = td;
} }
spin_unlock_irqrestore(&uhci->frame_list_lock, flags);
} }
static void uhci_remove_td(struct uhci_hcd *uhci, struct uhci_td *td) static void uhci_remove_td(struct uhci_hcd *uhci, struct uhci_td *td)
{ {
unsigned long flags;
/* If it's not inserted, don't remove it */ /* If it's not inserted, don't remove it */
spin_lock_irqsave(&uhci->frame_list_lock, flags);
if (td->frame == -1 && list_empty(&td->fl_list)) if (td->frame == -1 && list_empty(&td->fl_list))
goto out; return;
if (td->frame != -1 && uhci->fl->frame_cpu[td->frame] == td) { if (td->frame != -1 && uhci->fl->frame_cpu[td->frame] == td) {
if (list_empty(&td->fl_list)) { if (list_empty(&td->fl_list)) {
...@@ -240,9 +223,6 @@ static void uhci_remove_td(struct uhci_hcd *uhci, struct uhci_td *td) ...@@ -240,9 +223,6 @@ static void uhci_remove_td(struct uhci_hcd *uhci, struct uhci_td *td)
list_del_init(&td->fl_list); list_del_init(&td->fl_list);
td->frame = -1; td->frame = -1;
out:
spin_unlock_irqrestore(&uhci->frame_list_lock, flags);
} }
/* /*
...@@ -339,12 +319,11 @@ static void uhci_free_qh(struct uhci_hcd *uhci, struct uhci_qh *qh) ...@@ -339,12 +319,11 @@ static void uhci_free_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
/* /*
* Append this urb's qh after the last qh in skelqh->list * Append this urb's qh after the last qh in skelqh->list
* MUST be called with uhci->frame_list_lock acquired
* *
* Note that urb_priv.queue_list doesn't have a separate queue head; * Note that urb_priv.queue_list doesn't have a separate queue head;
* it's a ring with every element "live". * it's a ring with every element "live".
*/ */
static void _uhci_insert_qh(struct uhci_hcd *uhci, struct uhci_qh *skelqh, struct urb *urb) static void uhci_insert_qh(struct uhci_hcd *uhci, struct uhci_qh *skelqh, struct urb *urb)
{ {
struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv; struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
struct list_head *tmp; struct list_head *tmp;
...@@ -396,22 +375,12 @@ static void _uhci_insert_qh(struct uhci_hcd *uhci, struct uhci_qh *skelqh, struc ...@@ -396,22 +375,12 @@ static void _uhci_insert_qh(struct uhci_hcd *uhci, struct uhci_qh *skelqh, struc
list_add_tail(&urbp->qh->list, &skelqh->list); list_add_tail(&urbp->qh->list, &skelqh->list);
} }
static void uhci_insert_qh(struct uhci_hcd *uhci, struct uhci_qh *skelqh, struct urb *urb)
{
unsigned long flags;
spin_lock_irqsave(&uhci->frame_list_lock, flags);
_uhci_insert_qh(uhci, skelqh, urb);
spin_unlock_irqrestore(&uhci->frame_list_lock, flags);
}
/* /*
* Start removal of QH from schedule; it finishes next frame. * Start removal of QH from schedule; it finishes next frame.
* TDs should be unlinked before this is called. * TDs should be unlinked before this is called.
*/ */
static void uhci_remove_qh(struct uhci_hcd *uhci, struct uhci_qh *qh) static void uhci_remove_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
{ {
unsigned long flags;
struct uhci_qh *pqh; struct uhci_qh *pqh;
if (!qh) if (!qh)
...@@ -420,7 +389,6 @@ static void uhci_remove_qh(struct uhci_hcd *uhci, struct uhci_qh *qh) ...@@ -420,7 +389,6 @@ static void uhci_remove_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
/* /*
* Only go through the hoops if it's actually linked in * Only go through the hoops if it's actually linked in
*/ */
spin_lock_irqsave(&uhci->frame_list_lock, flags);
if (!list_empty(&qh->list)) { if (!list_empty(&qh->list)) {
pqh = list_entry(qh->list.prev, struct uhci_qh, list); pqh = list_entry(qh->list.prev, struct uhci_qh, list);
...@@ -456,20 +424,15 @@ static void uhci_remove_qh(struct uhci_hcd *uhci, struct uhci_qh *qh) ...@@ -456,20 +424,15 @@ static void uhci_remove_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
} }
list_del_init(&qh->list); list_del_init(&qh->list);
} }
spin_unlock_irqrestore(&uhci->frame_list_lock, flags);
qh->urbp = NULL; qh->urbp = NULL;
spin_lock_irqsave(&uhci->qh_remove_list_lock, flags);
/* Check to see if the remove list is empty. Set the IOC bit */ /* Check to see if the remove list is empty. Set the IOC bit */
/* to force an interrupt so we can remove the QH */ /* to force an interrupt so we can remove the QH */
if (list_empty(&uhci->qh_remove_list)) if (list_empty(&uhci->qh_remove_list))
uhci_set_next_interrupt(uhci); uhci_set_next_interrupt(uhci);
list_add(&qh->remove_list, &uhci->qh_remove_list); list_add(&qh->remove_list, &uhci->qh_remove_list);
spin_unlock_irqrestore(&uhci->qh_remove_list_lock, flags);
} }
static int uhci_fixup_toggle(struct urb *urb, unsigned int toggle) static int uhci_fixup_toggle(struct urb *urb, unsigned int toggle)
...@@ -503,13 +466,10 @@ static void uhci_append_queued_urb(struct uhci_hcd *uhci, struct urb *eurb, stru ...@@ -503,13 +466,10 @@ static void uhci_append_queued_urb(struct uhci_hcd *uhci, struct urb *eurb, stru
struct urb_priv *eurbp, *urbp, *furbp, *lurbp; struct urb_priv *eurbp, *urbp, *furbp, *lurbp;
struct list_head *tmp; struct list_head *tmp;
struct uhci_td *lltd; struct uhci_td *lltd;
unsigned long flags;
eurbp = eurb->hcpriv; eurbp = eurb->hcpriv;
urbp = urb->hcpriv; urbp = urb->hcpriv;
spin_lock_irqsave(&uhci->frame_list_lock, flags);
/* Find the first URB in the queue */ /* Find the first URB in the queue */
if (eurbp->queued) { if (eurbp->queued) {
struct list_head *head = &eurbp->queue_list; struct list_head *head = &eurbp->queue_list;
...@@ -549,8 +509,6 @@ static void uhci_append_queued_urb(struct uhci_hcd *uhci, struct urb *eurb, stru ...@@ -549,8 +509,6 @@ static void uhci_append_queued_urb(struct uhci_hcd *uhci, struct urb *eurb, stru
list_add_tail(&urbp->queue_list, &furbp->queue_list); list_add_tail(&urbp->queue_list, &furbp->queue_list);
urbp->queued = 1; urbp->queued = 1;
spin_unlock_irqrestore(&uhci->frame_list_lock, flags);
} }
static void uhci_delete_queued_urb(struct uhci_hcd *uhci, struct urb *urb) static void uhci_delete_queued_urb(struct uhci_hcd *uhci, struct urb *urb)
...@@ -560,14 +518,11 @@ static void uhci_delete_queued_urb(struct uhci_hcd *uhci, struct urb *urb) ...@@ -560,14 +518,11 @@ static void uhci_delete_queued_urb(struct uhci_hcd *uhci, struct urb *urb)
struct urb_priv *purbp; struct urb_priv *purbp;
struct uhci_td *pltd; struct uhci_td *pltd;
unsigned int toggle; unsigned int toggle;
unsigned long flags;
urbp = urb->hcpriv; urbp = urb->hcpriv;
spin_lock_irqsave(&uhci->frame_list_lock, flags);
if (list_empty(&urbp->queue_list)) if (list_empty(&urbp->queue_list))
goto out; return;
nurbp = list_entry(urbp->queue_list.next, struct urb_priv, queue_list); nurbp = list_entry(urbp->queue_list.next, struct urb_priv, queue_list);
...@@ -625,9 +580,6 @@ static void uhci_delete_queued_urb(struct uhci_hcd *uhci, struct urb *urb) ...@@ -625,9 +580,6 @@ static void uhci_delete_queued_urb(struct uhci_hcd *uhci, struct urb *urb)
} }
list_del_init(&urbp->queue_list); list_del_init(&urbp->queue_list);
out:
spin_unlock_irqrestore(&uhci->frame_list_lock, flags);
} }
static struct urb_priv *uhci_alloc_urb_priv(struct uhci_hcd *uhci, struct urb *urb) static struct urb_priv *uhci_alloc_urb_priv(struct uhci_hcd *uhci, struct urb *urb)
...@@ -655,9 +607,6 @@ static struct urb_priv *uhci_alloc_urb_priv(struct uhci_hcd *uhci, struct urb *u ...@@ -655,9 +607,6 @@ static struct urb_priv *uhci_alloc_urb_priv(struct uhci_hcd *uhci, struct urb *u
return urbp; return urbp;
} }
/*
* MUST be called with urb->lock acquired
*/
static void uhci_add_td_to_urb(struct urb *urb, struct uhci_td *td) static void uhci_add_td_to_urb(struct urb *urb, struct uhci_td *td)
{ {
struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv; struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
...@@ -667,9 +616,6 @@ static void uhci_add_td_to_urb(struct urb *urb, struct uhci_td *td) ...@@ -667,9 +616,6 @@ static void uhci_add_td_to_urb(struct urb *urb, struct uhci_td *td)
list_add_tail(&td->list, &urbp->td_list); list_add_tail(&td->list, &urbp->td_list);
} }
/*
* MUST be called with urb->lock acquired
*/
static void uhci_remove_td_from_urb(struct uhci_td *td) static void uhci_remove_td_from_urb(struct uhci_td *td)
{ {
if (list_empty(&td->list)) if (list_empty(&td->list))
...@@ -680,14 +626,10 @@ static void uhci_remove_td_from_urb(struct uhci_td *td) ...@@ -680,14 +626,10 @@ static void uhci_remove_td_from_urb(struct uhci_td *td)
td->urb = NULL; td->urb = NULL;
} }
/*
* MUST be called with urb->lock acquired
*/
static void uhci_destroy_urb_priv(struct uhci_hcd *uhci, struct urb *urb) static void uhci_destroy_urb_priv(struct uhci_hcd *uhci, struct urb *urb)
{ {
struct list_head *head, *tmp; struct list_head *head, *tmp;
struct urb_priv *urbp; struct urb_priv *urbp;
unsigned long flags;
urbp = (struct urb_priv *)urb->hcpriv; urbp = (struct urb_priv *)urb->hcpriv;
if (!urbp) if (!urbp)
...@@ -697,8 +639,6 @@ static void uhci_destroy_urb_priv(struct uhci_hcd *uhci, struct urb *urb) ...@@ -697,8 +639,6 @@ static void uhci_destroy_urb_priv(struct uhci_hcd *uhci, struct urb *urb)
dev_warn(uhci_dev(uhci), "urb %p still on uhci->urb_list " dev_warn(uhci_dev(uhci), "urb %p still on uhci->urb_list "
"or uhci->remove_list!\n", urb); "or uhci->remove_list!\n", urb);
spin_lock_irqsave(&uhci->td_remove_list_lock, flags);
/* Check to see if the remove list is empty. Set the IOC bit */ /* Check to see if the remove list is empty. Set the IOC bit */
/* to force an interrupt so we can remove the TD's*/ /* to force an interrupt so we can remove the TD's*/
if (list_empty(&uhci->td_remove_list)) if (list_empty(&uhci->td_remove_list))
...@@ -716,42 +656,30 @@ static void uhci_destroy_urb_priv(struct uhci_hcd *uhci, struct urb *urb) ...@@ -716,42 +656,30 @@ static void uhci_destroy_urb_priv(struct uhci_hcd *uhci, struct urb *urb)
list_add(&td->remove_list, &uhci->td_remove_list); list_add(&td->remove_list, &uhci->td_remove_list);
} }
spin_unlock_irqrestore(&uhci->td_remove_list_lock, flags);
urb->hcpriv = NULL; urb->hcpriv = NULL;
kmem_cache_free(uhci_up_cachep, urbp); kmem_cache_free(uhci_up_cachep, urbp);
} }
static void uhci_inc_fsbr(struct uhci_hcd *uhci, struct urb *urb) static void uhci_inc_fsbr(struct uhci_hcd *uhci, struct urb *urb)
{ {
unsigned long flags;
struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv; struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
spin_lock_irqsave(&uhci->frame_list_lock, flags);
if ((!(urb->transfer_flags & URB_NO_FSBR)) && !urbp->fsbr) { if ((!(urb->transfer_flags & URB_NO_FSBR)) && !urbp->fsbr) {
urbp->fsbr = 1; urbp->fsbr = 1;
if (!uhci->fsbr++ && !uhci->fsbrtimeout) if (!uhci->fsbr++ && !uhci->fsbrtimeout)
uhci->skel_term_qh->link = cpu_to_le32(uhci->skel_hs_control_qh->dma_handle) | UHCI_PTR_QH; uhci->skel_term_qh->link = cpu_to_le32(uhci->skel_hs_control_qh->dma_handle) | UHCI_PTR_QH;
} }
spin_unlock_irqrestore(&uhci->frame_list_lock, flags);
} }
static void uhci_dec_fsbr(struct uhci_hcd *uhci, struct urb *urb) static void uhci_dec_fsbr(struct uhci_hcd *uhci, struct urb *urb)
{ {
unsigned long flags;
struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv; struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
spin_lock_irqsave(&uhci->frame_list_lock, flags);
if ((!(urb->transfer_flags & URB_NO_FSBR)) && urbp->fsbr) { if ((!(urb->transfer_flags & URB_NO_FSBR)) && urbp->fsbr) {
urbp->fsbr = 0; urbp->fsbr = 0;
if (!--uhci->fsbr) if (!--uhci->fsbr)
uhci->fsbrtimeout = jiffies + FSBR_DELAY; uhci->fsbrtimeout = jiffies + FSBR_DELAY;
} }
spin_unlock_irqrestore(&uhci->frame_list_lock, flags);
} }
/* /*
...@@ -1365,9 +1293,6 @@ static int uhci_result_isochronous(struct uhci_hcd *uhci, struct urb *urb) ...@@ -1365,9 +1293,6 @@ static int uhci_result_isochronous(struct uhci_hcd *uhci, struct urb *urb)
return ret; return ret;
} }
/*
* MUST be called with uhci->urb_list_lock acquired
*/
static struct urb *uhci_find_urb_ep(struct uhci_hcd *uhci, struct urb *urb) static struct urb *uhci_find_urb_ep(struct uhci_hcd *uhci, struct urb *urb)
{ {
struct list_head *tmp, *head; struct list_head *tmp, *head;
...@@ -1405,7 +1330,7 @@ static int uhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, int mem_flags) ...@@ -1405,7 +1330,7 @@ static int uhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, int mem_flags)
struct urb *eurb; struct urb *eurb;
int bustime; int bustime;
spin_lock_irqsave(&uhci->urb_list_lock, flags); spin_lock_irqsave(&uhci->schedule_lock, flags);
if (urb->status != -EINPROGRESS) /* URB already unlinked! */ if (urb->status != -EINPROGRESS) /* URB already unlinked! */
goto out; goto out;
...@@ -1462,14 +1387,12 @@ static int uhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, int mem_flags) ...@@ -1462,14 +1387,12 @@ static int uhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, int mem_flags)
ret = 0; ret = 0;
out: out:
spin_unlock_irqrestore(&uhci->urb_list_lock, flags); spin_unlock_irqrestore(&uhci->schedule_lock, flags);
return ret; return ret;
} }
/* /*
* Return the result of a transfer * Return the result of a transfer
*
* MUST be called with urb_list_lock acquired
*/ */
static void uhci_transfer_result(struct uhci_hcd *uhci, struct urb *urb) static void uhci_transfer_result(struct uhci_hcd *uhci, struct urb *urb)
{ {
...@@ -1505,7 +1428,6 @@ static void uhci_transfer_result(struct uhci_hcd *uhci, struct urb *urb) ...@@ -1505,7 +1428,6 @@ static void uhci_transfer_result(struct uhci_hcd *uhci, struct urb *urb)
case PIPE_BULK: case PIPE_BULK:
case PIPE_ISOCHRONOUS: case PIPE_ISOCHRONOUS:
/* Release bandwidth for Interrupt or Isoc. transfers */ /* Release bandwidth for Interrupt or Isoc. transfers */
/* Spinlock needed ? */
if (urb->bandwidth) if (urb->bandwidth)
usb_release_bandwidth(urb->dev, urb, 1); usb_release_bandwidth(urb->dev, urb, 1);
uhci_unlink_generic(uhci, urb); uhci_unlink_generic(uhci, urb);
...@@ -1513,15 +1435,12 @@ static void uhci_transfer_result(struct uhci_hcd *uhci, struct urb *urb) ...@@ -1513,15 +1435,12 @@ static void uhci_transfer_result(struct uhci_hcd *uhci, struct urb *urb)
case PIPE_INTERRUPT: case PIPE_INTERRUPT:
/* Release bandwidth for Interrupt or Isoc. transfers */ /* Release bandwidth for Interrupt or Isoc. transfers */
/* Make sure we don't release if we have a queued URB */ /* Make sure we don't release if we have a queued URB */
spin_lock(&uhci->frame_list_lock);
/* Spinlock needed ? */
if (list_empty(&urbp->queue_list) && urb->bandwidth) if (list_empty(&urbp->queue_list) && urb->bandwidth)
usb_release_bandwidth(urb->dev, urb, 0); usb_release_bandwidth(urb->dev, urb, 0);
else else
/* bandwidth was passed on to queued URB, */ /* bandwidth was passed on to queued URB, */
/* so don't let usb_unlink_urb() release it */ /* so don't let usb_unlink_urb() release it */
urb->bandwidth = 0; urb->bandwidth = 0;
spin_unlock(&uhci->frame_list_lock);
uhci_unlink_generic(uhci, urb); uhci_unlink_generic(uhci, urb);
break; break;
default: default:
...@@ -1537,9 +1456,6 @@ static void uhci_transfer_result(struct uhci_hcd *uhci, struct urb *urb) ...@@ -1537,9 +1456,6 @@ static void uhci_transfer_result(struct uhci_hcd *uhci, struct urb *urb)
spin_unlock(&urb->lock); spin_unlock(&urb->lock);
} }
/*
* MUST be called with urb->lock acquired
*/
static void uhci_unlink_generic(struct uhci_hcd *uhci, struct urb *urb) static void uhci_unlink_generic(struct uhci_hcd *uhci, struct urb *urb)
{ {
struct list_head *head, *tmp; struct list_head *head, *tmp;
...@@ -1595,7 +1511,7 @@ static int uhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb) ...@@ -1595,7 +1511,7 @@ static int uhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb)
unsigned long flags; unsigned long flags;
struct urb_priv *urbp; struct urb_priv *urbp;
spin_lock_irqsave(&uhci->urb_list_lock, flags); spin_lock_irqsave(&uhci->schedule_lock, flags);
urbp = urb->hcpriv; urbp = urb->hcpriv;
if (!urbp) /* URB was never linked! */ if (!urbp) /* URB was never linked! */
goto done; goto done;
...@@ -1603,16 +1519,13 @@ static int uhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb) ...@@ -1603,16 +1519,13 @@ static int uhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb)
uhci_unlink_generic(uhci, urb); uhci_unlink_generic(uhci, urb);
spin_lock(&uhci->urb_remove_list_lock);
/* If we're the first, set the next interrupt bit */ /* If we're the first, set the next interrupt bit */
if (list_empty(&uhci->urb_remove_list)) if (list_empty(&uhci->urb_remove_list))
uhci_set_next_interrupt(uhci); uhci_set_next_interrupt(uhci);
list_add_tail(&urbp->urb_list, &uhci->urb_remove_list); list_add_tail(&urbp->urb_list, &uhci->urb_remove_list);
spin_unlock(&uhci->urb_remove_list_lock);
done: done:
spin_unlock_irqrestore(&uhci->urb_list_lock, flags); spin_unlock_irqrestore(&uhci->schedule_lock, flags);
return 0; return 0;
} }
...@@ -1674,7 +1587,7 @@ static void stall_callback(unsigned long ptr) ...@@ -1674,7 +1587,7 @@ static void stall_callback(unsigned long ptr)
INIT_LIST_HEAD(&list); INIT_LIST_HEAD(&list);
spin_lock_irqsave(&uhci->urb_list_lock, flags); spin_lock_irqsave(&uhci->schedule_lock, flags);
head = &uhci->urb_list; head = &uhci->urb_list;
tmp = head->next; tmp = head->next;
while (tmp != head) { while (tmp != head) {
...@@ -1690,12 +1603,15 @@ static void stall_callback(unsigned long ptr) ...@@ -1690,12 +1603,15 @@ static void stall_callback(unsigned long ptr)
uhci_fsbr_timeout(uhci, u); uhci_fsbr_timeout(uhci, u);
/* Check if the URB timed out */ /* Check if the URB timed out */
if (u->timeout && time_after_eq(jiffies, up->inserttime + u->timeout)) if (u->timeout && u->status == -EINPROGRESS &&
time_after_eq(jiffies, up->inserttime + u->timeout)) {
u->status = -ETIMEDOUT;
list_move_tail(&up->urb_list, &list); list_move_tail(&up->urb_list, &list);
}
spin_unlock(&u->lock); spin_unlock(&u->lock);
} }
spin_unlock_irqrestore(&uhci->urb_list_lock, flags); spin_unlock_irqrestore(&uhci->schedule_lock, flags);
head = &list; head = &list;
tmp = head->next; tmp = head->next;
...@@ -1737,7 +1653,6 @@ static void uhci_free_pending_qhs(struct uhci_hcd *uhci) ...@@ -1737,7 +1653,6 @@ static void uhci_free_pending_qhs(struct uhci_hcd *uhci)
{ {
struct list_head *tmp, *head; struct list_head *tmp, *head;
spin_lock(&uhci->qh_remove_list_lock);
head = &uhci->qh_remove_list; head = &uhci->qh_remove_list;
tmp = head->next; tmp = head->next;
while (tmp != head) { while (tmp != head) {
...@@ -1749,14 +1664,12 @@ static void uhci_free_pending_qhs(struct uhci_hcd *uhci) ...@@ -1749,14 +1664,12 @@ static void uhci_free_pending_qhs(struct uhci_hcd *uhci)
uhci_free_qh(uhci, qh); uhci_free_qh(uhci, qh);
} }
spin_unlock(&uhci->qh_remove_list_lock);
} }
static void uhci_free_pending_tds(struct uhci_hcd *uhci) static void uhci_free_pending_tds(struct uhci_hcd *uhci)
{ {
struct list_head *tmp, *head; struct list_head *tmp, *head;
spin_lock(&uhci->td_remove_list_lock);
head = &uhci->td_remove_list; head = &uhci->td_remove_list;
tmp = head->next; tmp = head->next;
while (tmp != head) { while (tmp != head) {
...@@ -1768,18 +1681,17 @@ static void uhci_free_pending_tds(struct uhci_hcd *uhci) ...@@ -1768,18 +1681,17 @@ static void uhci_free_pending_tds(struct uhci_hcd *uhci)
uhci_free_td(uhci, td); uhci_free_td(uhci, td);
} }
spin_unlock(&uhci->td_remove_list_lock);
} }
static void uhci_finish_urb(struct usb_hcd *hcd, struct urb *urb, struct pt_regs *regs) static void uhci_finish_urb(struct usb_hcd *hcd, struct urb *urb, struct pt_regs *regs)
{ {
struct uhci_hcd *uhci = hcd_to_uhci(hcd); struct uhci_hcd *uhci = hcd_to_uhci(hcd);
spin_lock(&urb->lock);
uhci_destroy_urb_priv(uhci, urb); uhci_destroy_urb_priv(uhci, urb);
spin_unlock(&urb->lock);
spin_unlock(&uhci->schedule_lock);
usb_hcd_giveback_urb(hcd, urb, regs); usb_hcd_giveback_urb(hcd, urb, regs);
spin_lock(&uhci->schedule_lock);
} }
static void uhci_finish_completion(struct usb_hcd *hcd, struct pt_regs *regs) static void uhci_finish_completion(struct usb_hcd *hcd, struct pt_regs *regs)
...@@ -1787,7 +1699,6 @@ static void uhci_finish_completion(struct usb_hcd *hcd, struct pt_regs *regs) ...@@ -1787,7 +1699,6 @@ static void uhci_finish_completion(struct usb_hcd *hcd, struct pt_regs *regs)
struct uhci_hcd *uhci = hcd_to_uhci(hcd); struct uhci_hcd *uhci = hcd_to_uhci(hcd);
struct list_head *tmp, *head; struct list_head *tmp, *head;
spin_lock(&uhci->complete_list_lock);
head = &uhci->complete_list; head = &uhci->complete_list;
tmp = head->next; tmp = head->next;
while (tmp != head) { while (tmp != head) {
...@@ -1795,26 +1706,18 @@ static void uhci_finish_completion(struct usb_hcd *hcd, struct pt_regs *regs) ...@@ -1795,26 +1706,18 @@ static void uhci_finish_completion(struct usb_hcd *hcd, struct pt_regs *regs)
struct urb *urb = urbp->urb; struct urb *urb = urbp->urb;
list_del_init(&urbp->urb_list); list_del_init(&urbp->urb_list);
spin_unlock(&uhci->complete_list_lock);
uhci_finish_urb(hcd, urb, regs); uhci_finish_urb(hcd, urb, regs);
spin_lock(&uhci->complete_list_lock);
head = &uhci->complete_list; head = &uhci->complete_list;
tmp = head->next; tmp = head->next;
} }
spin_unlock(&uhci->complete_list_lock);
} }
static void uhci_remove_pending_urbps(struct uhci_hcd *uhci) static void uhci_remove_pending_urbps(struct uhci_hcd *uhci)
{ {
spin_lock(&uhci->urb_remove_list_lock);
spin_lock(&uhci->complete_list_lock);
/* Splice the urb_remove_list onto the end of the complete_list */ /* Splice the urb_remove_list onto the end of the complete_list */
list_splice_init(&uhci->urb_remove_list, uhci->complete_list.prev); list_splice_init(&uhci->urb_remove_list, uhci->complete_list.prev);
spin_unlock(&uhci->complete_list_lock);
spin_unlock(&uhci->urb_remove_list_lock);
} }
static irqreturn_t uhci_irq(struct usb_hcd *hcd, struct pt_regs *regs) static irqreturn_t uhci_irq(struct usb_hcd *hcd, struct pt_regs *regs)
...@@ -1851,16 +1754,15 @@ static irqreturn_t uhci_irq(struct usb_hcd *hcd, struct pt_regs *regs) ...@@ -1851,16 +1754,15 @@ static irqreturn_t uhci_irq(struct usb_hcd *hcd, struct pt_regs *regs)
if (status & USBSTS_RD) if (status & USBSTS_RD)
uhci->resume_detect = 1; uhci->resume_detect = 1;
uhci_free_pending_qhs(uhci); spin_lock(&uhci->schedule_lock);
uhci_free_pending_qhs(uhci);
uhci_free_pending_tds(uhci); uhci_free_pending_tds(uhci);
uhci_remove_pending_urbps(uhci); uhci_remove_pending_urbps(uhci);
uhci_clear_next_interrupt(uhci); uhci_clear_next_interrupt(uhci);
/* Walk the list of pending URB's to see which ones completed */ /* Walk the list of pending URB's to see which ones completed */
spin_lock(&uhci->urb_list_lock);
head = &uhci->urb_list; head = &uhci->urb_list;
tmp = head->next; tmp = head->next;
while (tmp != head) { while (tmp != head) {
...@@ -1872,9 +1774,10 @@ static irqreturn_t uhci_irq(struct usb_hcd *hcd, struct pt_regs *regs) ...@@ -1872,9 +1774,10 @@ static irqreturn_t uhci_irq(struct usb_hcd *hcd, struct pt_regs *regs)
/* Checks the status and does all of the magic necessary */ /* Checks the status and does all of the magic necessary */
uhci_transfer_result(uhci, urb); uhci_transfer_result(uhci, urb);
} }
spin_unlock(&uhci->urb_list_lock);
uhci_finish_completion(hcd, regs); uhci_finish_completion(hcd, regs);
spin_unlock(&uhci->schedule_lock);
return IRQ_HANDLED; return IRQ_HANDLED;
} }
...@@ -2164,23 +2067,17 @@ static int uhci_start(struct usb_hcd *hcd) ...@@ -2164,23 +2067,17 @@ static int uhci_start(struct usb_hcd *hcd)
uhci->fsbr = 0; uhci->fsbr = 0;
uhci->fsbrtimeout = 0; uhci->fsbrtimeout = 0;
spin_lock_init(&uhci->qh_remove_list_lock); spin_lock_init(&uhci->schedule_lock);
INIT_LIST_HEAD(&uhci->qh_remove_list); INIT_LIST_HEAD(&uhci->qh_remove_list);
spin_lock_init(&uhci->td_remove_list_lock);
INIT_LIST_HEAD(&uhci->td_remove_list); INIT_LIST_HEAD(&uhci->td_remove_list);
spin_lock_init(&uhci->urb_remove_list_lock);
INIT_LIST_HEAD(&uhci->urb_remove_list); INIT_LIST_HEAD(&uhci->urb_remove_list);
spin_lock_init(&uhci->urb_list_lock);
INIT_LIST_HEAD(&uhci->urb_list); INIT_LIST_HEAD(&uhci->urb_list);
spin_lock_init(&uhci->complete_list_lock);
INIT_LIST_HEAD(&uhci->complete_list); INIT_LIST_HEAD(&uhci->complete_list);
spin_lock_init(&uhci->frame_list_lock);
uhci->fl = dma_alloc_coherent(uhci_dev(uhci), sizeof(*uhci->fl), uhci->fl = dma_alloc_coherent(uhci_dev(uhci), sizeof(*uhci->fl),
&dma_handle, 0); &dma_handle, 0);
if (!uhci->fl) { if (!uhci->fl) {
...@@ -2372,7 +2269,6 @@ static int uhci_start(struct usb_hcd *hcd) ...@@ -2372,7 +2269,6 @@ static int uhci_start(struct usb_hcd *hcd)
static void uhci_stop(struct usb_hcd *hcd) static void uhci_stop(struct usb_hcd *hcd)
{ {
struct uhci_hcd *uhci = hcd_to_uhci(hcd); struct uhci_hcd *uhci = hcd_to_uhci(hcd);
unsigned long flags;
del_timer_sync(&uhci->stall_timer); del_timer_sync(&uhci->stall_timer);
...@@ -2380,16 +2276,18 @@ static void uhci_stop(struct usb_hcd *hcd) ...@@ -2380,16 +2276,18 @@ static void uhci_stop(struct usb_hcd *hcd)
* At this point, we're guaranteed that no new connects can be made * At this point, we're guaranteed that no new connects can be made
* to this bus since there are no more parents * to this bus since there are no more parents
*/ */
local_irq_save(flags); spin_lock_irq(&uhci->schedule_lock);
uhci_free_pending_qhs(uhci); uhci_free_pending_qhs(uhci);
uhci_free_pending_tds(uhci); uhci_free_pending_tds(uhci);
uhci_remove_pending_urbps(uhci); uhci_remove_pending_urbps(uhci);
spin_unlock_irq(&uhci->schedule_lock);
reset_hc(uhci); reset_hc(uhci);
spin_lock_irq(&uhci->schedule_lock);
uhci_free_pending_qhs(uhci); uhci_free_pending_qhs(uhci);
uhci_free_pending_tds(uhci); uhci_free_pending_tds(uhci);
local_irq_restore(flags); spin_unlock_irq(&uhci->schedule_lock);
release_uhci(uhci); release_uhci(uhci);
} }
......
drivers/usb/host/uhci-hcd.h
View file @ 33d61f24
...@@ -342,8 +342,8 @@ struct uhci_hcd { ...@@ -342,8 +342,8 @@ struct uhci_hcd {
struct uhci_td *term_td; /* Terminating TD, see UHCI bug */ struct uhci_td *term_td; /* Terminating TD, see UHCI bug */
struct uhci_qh *skelqh[UHCI_NUM_SKELQH]; /* Skeleton QH's */ struct uhci_qh *skelqh[UHCI_NUM_SKELQH]; /* Skeleton QH's */
spinlock_t frame_list_lock; spinlock_t schedule_lock;
struct uhci_frame_list *fl; /* P: uhci->frame_list_lock */ struct uhci_frame_list *fl; /* P: uhci->schedule_lock */
int fsbr; /* Full-speed bandwidth reclamation */ int fsbr; /* Full-speed bandwidth reclamation */
unsigned long fsbrtimeout; /* FSBR delay */ unsigned long fsbrtimeout; /* FSBR delay */
...@@ -353,24 +353,19 @@ struct uhci_hcd { ...@@ -353,24 +353,19 @@ struct uhci_hcd {
unsigned int saved_framenumber; /* Save during PM suspend */ unsigned int saved_framenumber; /* Save during PM suspend */
/* Main list of URB's currently controlled by this HC */ /* Main list of URB's currently controlled by this HC */
spinlock_t urb_list_lock; struct list_head urb_list; /* P: uhci->schedule_lock */
struct list_head urb_list; /* P: uhci->urb_list_lock */
/* List of QH's that are done, but waiting to be unlinked (race) */ /* List of QH's that are done, but waiting to be unlinked (race) */
spinlock_t qh_remove_list_lock; struct list_head qh_remove_list; /* P: uhci->schedule_lock */
struct list_head qh_remove_list; /* P: uhci->qh_remove_list_lock */
/* List of TD's that are done, but waiting to be freed (race) */ /* List of TD's that are done, but waiting to be freed (race) */
spinlock_t td_remove_list_lock; struct list_head td_remove_list; /* P: uhci->schedule_lock */
struct list_head td_remove_list; /* P: uhci->td_remove_list_lock */
/* List of asynchronously unlinked URB's */ /* List of asynchronously unlinked URB's */
spinlock_t urb_remove_list_lock; struct list_head urb_remove_list; /* P: uhci->schedule_lock */
struct list_head urb_remove_list; /* P: uhci->urb_remove_list_lock */
/* List of URB's awaiting completion callback */ /* List of URB's awaiting completion callback */
spinlock_t complete_list_lock; struct list_head complete_list; /* P: uhci->schedule_lock */
struct list_head complete_list; /* P: uhci->complete_list_lock */
int rh_numports; int rh_numports;
...@@ -401,26 +396,15 @@ struct urb_priv { ...@@ -401,26 +396,15 @@ struct urb_priv {
/* /*
* Locking in uhci.c * Locking in uhci.c
* *
* spinlocks are used extensively to protect the many lists and data * Almost everything relating to the hardware schedule and processing
* structures we have. It's not that pretty, but it's necessary. We * of URBs is protected by uhci->schedule_lock. urb->status is protected
* need to be done with all of the locks (except complete_list_lock) when * by urb->lock; that's the one exception.
* we call urb->complete. I've tried to make it simple enough so I don't
* have to spend hours racking my brain trying to figure out if the
* locking is safe.
* *
* Here's the safe locking order to prevent deadlocks: * To prevent deadlocks, never lock uhci->schedule_lock while holding
* urb->lock. The safe order of locking is:
* *
* #1 uhci->urb_list_lock * #1 uhci->schedule_lock
* #2 urb->lock * #2 urb->lock
* #3 uhci->urb_remove_list_lock, uhci->frame_list_lock,
* uhci->qh_remove_list_lock
* #4 uhci->complete_list_lock
*
* If you're going to grab 2 or more locks at once, ALWAYS grab the lock
* at the lowest level FIRST and NEVER grab locks at the same level at the
* same time.
*
* So, if you need uhci->urb_list_lock, grab it before you grab urb->lock
*/ */
#endif #endif
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