Fork us on GitHub Follow us on Facebook Follow us on Twitter

Changeset 4702bde in mainline


Ignore:
Timestamp:
2009-12-02T18:53:26Z (11 years ago)
Author:
Jakub Jermar <jakub@…>
Branches:
master
Children:
e15e0e8
Parents:
12bef5b
Message:

Fix atomic addition in arm32 kernel.

File:
1 edited

Legend:

Unmodified
Added
Removed
  • kernel/arch/arm32/include/atomic.h

    r12bef5b r4702bde  
    3737#define KERN_arm32_ATOMIC_H_
    3838
     39#include <arch/asm.h>
     40
    3941/** Atomic addition.
    4042 *
     
    4749static inline long atomic_add(atomic_t *val, int i)
    4850{
    49         int ret;
    50         volatile long *mem = &(val->count);
    51        
    52         asm volatile (
    53                 "1:\n"
    54                         "ldr r2, [%[mem]]\n"
    55                         "add r3, r2, %[i]\n"
    56                         "str r3, %[ret]\n"
    57                         "swp r3, r3, [%[mem]]\n"
    58                         "cmp r3, r2\n"
    59                         "bne 1b\n"
    60                 : [ret] "=m" (ret)
    61                 : [mem] "r" (mem), [i] "r" (i)
    62                 : "r3", "r2"
    63         );
     51        long ret;
     52
     53        /*
     54         * This implementation is for UP pre-ARMv6 systems where we do not have
     55         * the LDREX and STREX instructions.
     56         */
     57        ipl_t ipl = interrupts_disable();
     58        val->count += i;
     59        ret = val->count;
     60        interrupts_restore(ipl);
    6461       
    6562        return ret;
Note: See TracChangeset for help on using the changeset viewer.