isdn: hisax: Replace the bogus access to irq stats

commit 40f08a724fcc21285cf3a75aec957aef908605c6 upstream.

Abusing irq stats in a driver for counting interrupts is a horrible
idea and not safe with shared interrupts. Replace it by a local
interrupt counter.

Noticed by the attempt to remove the irq stats export.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

diff --git a/drivers/isdn/hisax/config.c b/drivers/isdn/hisax/config.c
index 544cf4b1cce3a1580b512d33d80dd92d428e754d..0a347a8a9eee7f9e3017ead48091aa767fdfe99a 100644 (file)
--- a/drivers/isdn/hisax/config.c
+++ b/drivers/isdn/hisax/config.c
@@ -801,6 +801,16 @@ static void closecard(int cardnr)
        ll_unload(csta);
 }
 
+static irqreturn_t card_irq(int intno, void *dev_id)
+{
+       struct IsdnCardState *cs = dev_id;
+       irqreturn_t ret = cs->irq_func(intno, cs);
+
+       if (ret == IRQ_HANDLED)
+               cs->irq_cnt++;
+       return ret;
+}
+
 static int init_card(struct IsdnCardState *cs)
 {
        int     irq_cnt, cnt = 3, ret;
@@ -809,10 +819,10 @@ static int init_card(struct IsdnCardState *cs)
                ret = cs->cardmsg(cs, CARD_INIT, NULL);
                return(ret);
        }
-       irq_cnt = kstat_irqs(cs->irq);
+       irq_cnt = cs->irq_cnt = 0;
        printk(KERN_INFO "%s: IRQ %d count %d\n", CardType[cs->typ],
               cs->irq, irq_cnt);
-       if (request_irq(cs->irq, cs->irq_func, cs->irq_flags, "HiSax", cs)) {
+       if (request_irq(cs->irq, card_irq, cs->irq_flags, "HiSax", cs)) {
                printk(KERN_WARNING "HiSax: couldn't get interrupt %d\n",
                       cs->irq);
                return 1;
@@ -822,8 +832,8 @@ static int init_card(struct IsdnCardState *cs)
                /* Timeout 10ms */
                msleep(10);
                printk(KERN_INFO "%s: IRQ %d count %d\n",
-                      CardType[cs->typ], cs->irq, kstat_irqs(cs->irq));
-               if (kstat_irqs(cs->irq) == irq_cnt) {
+                      CardType[cs->typ], cs->irq, cs->irq_cnt);
+               if (cs->irq_cnt == irq_cnt) {
                        printk(KERN_WARNING
                               "%s: IRQ(%d) getting no interrupts during init %d\n",
                               CardType[cs->typ], cs->irq, 4 - cnt);

diff --git a/drivers/isdn/hisax/hisax.h b/drivers/isdn/hisax/hisax.h
index 832a87855ffb5900fa22ded56b5586ed907ed886..32ab3924aa7341f5f390623faee36d9a308abc67 100644 (file)
--- a/drivers/isdn/hisax/hisax.h
+++ b/drivers/isdn/hisax/hisax.h
@@ -959,6 +959,7 @@ struct IsdnCardState {
        u_long          event;
        struct work_struct tqueue;
        struct timer_list dbusytimer;
+       unsigned int    irq_cnt;
 #ifdef ERROR_STATISTIC
        int             err_crc;
        int             err_tx;