[PATCH] Char: 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@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/char/mxser_new.c b/drivers/char/mxser_new.c
index 945c7e1b4c34fc0d5cd14f0ccda84ea30563d4c4..042d1381ff6f3479c1d6b018600bdd63f50bf58a 100644 (file)
--- 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: