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[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>
This commit is contained in:
Jiri Slaby 2007-02-10 01:45:19 -08:00 committed by Linus Torvalds
parent ed79ba12e9
commit 18b95576bc
1 changed files with 3 additions and 6 deletions
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9
drivers/char/mxser_new.c
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@ -56,7 +56,7 @@
#define MXSER_BOARDS 4 /* Max. boards */ #define MXSER_BOARDS 4 /* Max. boards */
#define MXSER_PORTS_PER_BOARD 8 /* Max. ports per board */ #define MXSER_PORTS_PER_BOARD 8 /* Max. ports per board */
#define MXSER_PORTS (MXSER_BOARDS * MXSER_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_IOADDR -1
#define MXSER_ERR_IRQ -2 #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_board *brd = NULL;
struct mxser_port *port; struct mxser_port *port;
int max, irqbits, bits, msr; int max, irqbits, bits, msr;
int pass_counter = 0; unsigned int int_cnt, pass_counter = 0;
unsigned int int_cnt;
int handled = IRQ_NONE; int handled = IRQ_NONE;
for (i = 0; i < MXSER_BOARDS; i++) for (i = 0; i < MXSER_BOARDS; i++)
@ -2237,7 +2236,7 @@ static irqreturn_t mxser_interrupt(int irq, void *dev_id)
if (brd == NULL) if (brd == NULL)
goto irq_stop; goto irq_stop;
max = brd->info->nports; max = brd->info->nports;
while (1) { while (pass_counter++ < MXSER_ISR_PASS_LIMIT) {
irqbits = inb(brd->vector) & brd->vector_mask; irqbits = inb(brd->vector) & brd->vector_mask;
if (irqbits == brd->vector_mask) if (irqbits == brd->vector_mask)
break; break;
@ -2308,8 +2307,6 @@ static irqreturn_t mxser_interrupt(int irq, void *dev_id)
} while (int_cnt++ < MXSER_ISR_PASS_LIMIT); } while (int_cnt++ < MXSER_ISR_PASS_LIMIT);
spin_unlock(&port->slock); spin_unlock(&port->slock);
} }
if (pass_counter++ > MXSER_ISR_PASS_LIMIT)
break; /* Prevent infinite loops */
} }
irq_stop: irq_stop: