http://www.ousob.com --- Legacy Redefined OuSob - File: /wwwroot/clipx/usr/include/asm-i386/mach-default/do_timer.h

/* defines for inline arch setup functions */ #include <asm/apic.h> #include <asm/i8259.h> /** * do_timer_interrupt_hook - hook into timer tick * @regs: standard registers from interrupt * * Description: * This hook is called immediately after the timer interrupt is ack'd. * It's primary purpose is to allow architectures that don't possess * individual per CPU clocks (like the CPU APICs supply) to broadcast the * timer interrupt as a means of triggering reschedules etc. **/ static inline void do_timer_interrupt_hook(struct pt_regs *regs) { do_timer(regs); #ifndef CONFIG_SMP update_process_times(user_mode(regs)); #endif /* * In the SMP case we use the local APIC timer interrupt to do the * profiling, except when we simulate SMP mode on a uniprocessor * system, in that case we have to call the local interrupt handler. */ #ifndef CONFIG_X86_LOCAL_APIC profile_tick(CPU_PROFILING, regs); #else if (!using_apic_timer) smp_local_timer_interrupt(regs); #endif } /* you can safely undefine this if you don't have the Neptune chipset */ #define BUGGY_NEPTUN_TIMER /** * do_timer_overflow - process a detected timer overflow condition * @count: hardware timer interrupt count on overflow * * Description: * This call is invoked when the jiffies count has not incremented but * the hardware timer interrupt has. It means that a timer tick interrupt * came along while the previous one was pending, thus a tick was missed **/ static inline int do_timer_overflow(int count) { int i; spin_lock(&i8259A_lock); /* * This is tricky when I/O APICs are used; * see do_timer_interrupt(). */ i = inb(0x20); spin_unlock(&i8259A_lock); /* assumption about timer being IRQ0 */ if (i & 0x01) { /* * We cannot detect lost timer interrupts ... * well, that's why we call them lost, don't we? :) * [hmm, on the Pentium and Alpha we can ... sort of] */ count -= LATCH; } else { #ifdef BUGGY_NEPTUN_TIMER /* * for the Neptun bug we know that the 'latch' * command doesn't latch the high and low value * of the counter atomically. Thus we have to * substract 256 from the counter * ... funny, isnt it? :) */ count -= 256; #else printk("do_slow_gettimeoffset(): hardware timer problem?\n"); #endif } return count; }