source: trunk/kernel/kern/do_interrupt.c @ 8

/*
 * kern/do_interrupt.c - kernel unified interrupt entry-point
 * 
 * Copyright (c) 2008,2009,2010,2011,2012 Ghassan Almaless
 * Copyright (c) 2011,2012 UPMC Sorbonne Universites
 *
 * This file is part of ALMOS-kernel.
 *
 * ALMOS-kernel is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2.0 of the License.
 *
 * ALMOS-kernel is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with ALMOS-kernel; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <cpu.h>
#include <task.h>
#include <thread.h>
#include <cpu-trace.h>
#include <chdev.h>
#include <system.h>
#include <signal.h>

#define irq_cpu_dmsg(c,...)                             \
        do{                                             \
                if(cpu_get_id() == (c))                 \
                        isr_dmsg(INFO, __VA_ARGS__);    \
        }while(0)

void do_interrupt(struct thread_s *this, uint_t irq_num)
{
        register thread_state_t old_state;
        struct irq_action_s *action;
        struct cpu_s *cpu;
        uint_t irq_state;
        error_t ret;

        cpu_trace_write(thread_current_cpu(this), do_interrupt);

        cpu = thread_current_cpu(this);

        cpu->irq_nr ++;
        old_state = this->state;

        if(old_state == S_USR)
        {
                this->state = S_KERNEL;
                tm_usr_compute(this);
        }

        arch_cpu_get_irq_entry(cpu, irq_num, &action);
        action->irq_handler(action);
           
        cpu_yield();

        if(old_state != S_USR)//and not a kernel thread ?
                return;

        /* it is safe to migrate as we are going to user *
         * space.                                        */
        if(thread_migration_isActivated(this))
        {
                thread_clear_cap_migrate(this);
                cpu_enable_all_irq(&irq_state);
                ret = thread_migrate(this,-1);
                cpu_restore_irq(irq_state);

                /* this pointer has expired */
                this = CURRENT_THREAD;
                cpu_wbflush();

                if(ret == 0)    
                        thread_migration_deactivate(this);
                else
                {
                        isr_dmsg(INFO, 
                        "%s: cpu %d, migration failed for victim pid %d, tid %d, err %d\n", 
                         __FUNCTION__, 
                         cpu_get_id(),
                         this->task->pid,
                         this->info.order,
                         ret);
                }
        }
        
        tm_sys_compute(this);
        this->state = S_USR;
        signal_notify(this);
}