[PATCH 3/4] Char: mxser_new, less loops in isr

From: Jiri Slaby
Date: Fri Dec 29 2006 - 15:56:47 EST


mxser_new, less loops in isr

Loop only 100^2 times, not 99999^2 times in isr (at most).

Signed-off-by: Jiri Slaby <jirislaby@xxxxxxxxx>

---
commit 5065aa25fd624e3477d993baebbf3255a1d492fa
tree a4b05ea113ceea8b8ad1382fa3a5778473597d0f
parent cc46acb974ba967794f7b199fb65ad4abd9531b7
author Jiri Slaby <jirislaby@xxxxxxxxx> Fri, 29 Dec 2006 21:07:10 +0059
committer Jiri Slaby <jirislaby@xxxxxxxxx> Fri, 29 Dec 2006 21:07:10 +0059

drivers/char/mxser_new.c | 9 +++------
1 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/drivers/char/mxser_new.c b/drivers/char/mxser_new.c
index 945c7e1..042d138 100644
--- a/drivers/char/mxser_new.c
+++ b/drivers/char/mxser_new.c
@@ -56,7 +56,7 @@
#define MXSER_BOARDS 4 /* Max. boards */
#define MXSER_PORTS_PER_BOARD 8 /* Max. ports per board */
#define MXSER_PORTS (MXSER_BOARDS * MXSER_PORTS_PER_BOARD)
-#define MXSER_ISR_PASS_LIMIT 99999L
+#define MXSER_ISR_PASS_LIMIT 100

#define MXSER_ERR_IOADDR -1
#define MXSER_ERR_IRQ -2
@@ -2222,8 +2222,7 @@ static irqreturn_t mxser_interrupt(int irq, void *dev_id)
struct mxser_board *brd = NULL;
struct mxser_port *port;
int max, irqbits, bits, msr;
- int pass_counter = 0;
- unsigned int int_cnt;
+ unsigned int int_cnt, pass_counter = 0;
int handled = IRQ_NONE;

for (i = 0; i < MXSER_BOARDS; i++)
@@ -2237,7 +2236,7 @@ static irqreturn_t mxser_interrupt(int irq, void *dev_id)
if (brd == NULL)
goto irq_stop;
max = brd->info->nports;
- while (1) {
+ while (pass_counter++ < MXSER_ISR_PASS_LIMIT) {
irqbits = inb(brd->vector) & brd->vector_mask;
if (irqbits == brd->vector_mask)
break;
@@ -2308,8 +2307,6 @@ static irqreturn_t mxser_interrupt(int irq, void *dev_id)
} while (int_cnt++ < MXSER_ISR_PASS_LIMIT);
spin_unlock(&port->slock);
}
- if (pass_counter++ > MXSER_ISR_PASS_LIMIT)
- break; /* Prevent infinite loops */
}

irq_stop:
-
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