include/asm-mips/hardirq.h

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1997, 1998, 1999, 2000, 2001 by Ralf Baechle
   7  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
   8  * Copyright (C) 2001 MIPS Technologies, Inc.
   9  */
  10 #ifndef _ASM_HARDIRQ_H
  11 #define _ASM_HARDIRQ_H
  12
  13 #include <linux/config.h>
  14 #include <linux/threads.h>
  15 #include <linux/irq.h>
  16
  17 typedef struct {
  18         unsigned int __softirq_pending;
  19 } ____cacheline_aligned irq_cpustat_t;
  20
  21 #include <linux/irq_cpustat.h>  /* Standard mappings for irq_cpustat_t above */
  22
  23 /*
  24  * We put the hardirq and softirq counter into the preemption
  25  * counter. The bitmask has the following meaning:
  26  *
  27  * - bits 0-7 are the preemption count (max preemption depth: 256)
  28  * - bits 8-15 are the softirq count (max # of softirqs: 256)
  29  * - bits 16-23 are the hardirq count (max # of hardirqs: 256)
  30  *
  31  * - ( bit 26 is the PREEMPT_ACTIVE flag. )
  32  *
  33  * PREEMPT_MASK: 0x000000ff
  34  * SOFTIRQ_MASK: 0x0000ff00
  35  * HARDIRQ_MASK: 0x00ff0000
  36  */
  37
  38 #define PREEMPT_BITS    8
  39 #define SOFTIRQ_BITS    8
  40 #define HARDIRQ_BITS    8
  41
  42 #define PREEMPT_SHIFT   0
  43 #define SOFTIRQ_SHIFT   (PREEMPT_SHIFT + PREEMPT_BITS)
  44 #define HARDIRQ_SHIFT   (SOFTIRQ_SHIFT + SOFTIRQ_BITS)
  45
  46 /*
  47  * The hardirq mask has to be large enough to have
  48  * space for potentially all IRQ sources in the system
  49  * nesting on a single CPU:
  50  */
  51 #if (1 << HARDIRQ_BITS) < NR_IRQS
  52 # error HARDIRQ_BITS is too low!
  53 #endif
  54
  55 #define irq_enter()             (preempt_count() += HARDIRQ_OFFSET)
  56 #define irq_exit()                                                     \
  57 do {                                                                   \
  58         preempt_count() -= IRQ_EXIT_OFFSET;                     \
  59         if (!in_interrupt() && softirq_pending(smp_processor_id())) \
  60                 do_softirq();                                   \
  61         preempt_enable_no_resched();                            \
  62 } while (0)
  63
  64 #endif /* _ASM_HARDIRQ_H */