Re: [patch] Real-Time Preemption, -RT-2.6.12-rc6-V0.7.48-00
From: Michal Schmidt
Date: Wed Jun 08 2005 - 12:55:28 EST
Hi,
I've made the soft IRQ flag feature work on x86_64. It compiles and
boots for me.
Attached is the patch against -RT-2.6.12-rc6-V0.7.48-01.
Michal
diff -Nurp -X linux-RT/Documentation/dontdiff linux-RT/arch/x86_64/kernel/apic.c linux-RT.mich/arch/x86_64/kernel/apic.c
--- linux-RT/arch/x86_64/kernel/apic.c 2005-06-07 14:05:16.000000000 +0200
+++ linux-RT.mich/arch/x86_64/kernel/apic.c 2005-06-08 18:51:21.000000000 +0200
@@ -478,10 +478,9 @@ static int lapic_suspend(struct sys_devi
apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
- local_save_flags(flags);
- local_irq_disable();
+ raw_local_irq_save(flags);
disable_local_APIC();
- local_irq_restore(flags);
+ raw_local_irq_restore(flags);
return 0;
}
@@ -496,7 +495,7 @@ static int lapic_resume(struct sys_devic
/* XXX: Pavel needs this for S3 resume, but can't explain why */
set_fixmap_nocache(FIX_APIC_BASE, APIC_DEFAULT_PHYS_BASE);
- local_irq_save(flags);
+ raw_local_irq_save(flags);
rdmsr(MSR_IA32_APICBASE, l, h);
l &= ~MSR_IA32_APICBASE_BASE;
l |= MSR_IA32_APICBASE_ENABLE | APIC_DEFAULT_PHYS_BASE;
@@ -519,7 +518,7 @@ static int lapic_resume(struct sys_devic
apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
apic_write(APIC_ESR, 0);
apic_read(APIC_ESR);
- local_irq_restore(flags);
+ raw_local_irq_restore(flags);
return 0;
}
@@ -676,7 +675,7 @@ static void setup_APIC_timer(unsigned in
{
unsigned long flags;
- local_irq_save(flags);
+ raw_local_irq_save(flags);
/* For some reasons this doesn't work on Simics, so fake it for now */
if (!strstr(boot_cpu_data.x86_model_id, "Screwdriver")) {
@@ -706,7 +705,7 @@ static void setup_APIC_timer(unsigned in
__setup_APIC_LVTT(clocks);
- local_irq_restore(flags);
+ raw_local_irq_restore(flags);
}
/*
@@ -763,7 +762,7 @@ void __init setup_boot_APIC_clock (void)
printk(KERN_INFO "Using local APIC timer interrupts.\n");
using_apic_timer = 1;
- local_irq_disable();
+ raw_local_irq_disable();
calibration_result = calibrate_APIC_clock();
/*
@@ -771,14 +770,14 @@ void __init setup_boot_APIC_clock (void)
*/
setup_APIC_timer(calibration_result);
- local_irq_enable();
+ raw_local_irq_enable();
}
void __init setup_secondary_APIC_clock(void)
{
- local_irq_disable(); /* FIXME: Do we need this? --RR */
+ raw_local_irq_disable(); /* FIXME: Do we need this? --RR */
setup_APIC_timer(calibration_result);
- local_irq_enable();
+ raw_local_irq_enable();
}
void __init disable_APIC_timer(void)
diff -Nurp -X linux-RT/Documentation/dontdiff linux-RT/arch/x86_64/kernel/irq.c linux-RT.mich/arch/x86_64/kernel/irq.c
--- linux-RT/arch/x86_64/kernel/irq.c 2005-03-02 08:38:07.000000000 +0100
+++ linux-RT.mich/arch/x86_64/kernel/irq.c 2005-06-08 19:13:26.000000000 +0200
@@ -43,7 +43,8 @@ int show_interrupts(struct seq_file *p,
}
if (i < NR_IRQS) {
- spin_lock_irqsave(&irq_desc[i].lock, flags);
+ raw_local_irq_save(flags);
+ spin_lock(&irq_desc[i].lock);
action = irq_desc[i].action;
if (!action)
goto skip;
@@ -63,7 +64,8 @@ int show_interrupts(struct seq_file *p,
seq_printf(p, ", %s", action->name);
seq_putc(p, '\n');
skip:
- spin_unlock_irqrestore(&irq_desc[i].lock, flags);
+ spin_unlock(&irq_desc[i].lock);
+ raw_local_irq_restore(flags);
} else if (i == NR_IRQS) {
seq_printf(p, "NMI: ");
for (j = 0; j < NR_CPUS; j++)
diff -Nurp -X linux-RT/Documentation/dontdiff linux-RT/arch/x86_64/kernel/process.c linux-RT.mich/arch/x86_64/kernel/process.c
--- linux-RT/arch/x86_64/kernel/process.c 2005-06-08 19:28:13.000000000 +0200
+++ linux-RT.mich/arch/x86_64/kernel/process.c 2005-06-08 19:01:05.000000000 +0200
@@ -85,13 +85,13 @@ EXPORT_SYMBOL(enable_hlt);
void default_idle(void)
{
if (!atomic_read(&hlt_counter)) {
- local_irq_disable();
+ raw_local_irq_disable();
if (!need_resched())
- safe_halt();
+ raw_safe_halt();
else
- local_irq_enable();
+ raw_local_irq_enable();
} else
- local_irq_enable();
+ raw_local_irq_enable();
}
/*
@@ -103,7 +103,7 @@ static void poll_idle (void)
{
int oldval;
- local_irq_enable();
+ raw_local_irq_enable();
/*
* Deal with another CPU just having chosen a thread to
@@ -164,6 +164,8 @@ void cpu_idle (void)
{
/* endless idle loop with no priority at all */
while (1) {
+ BUG_ON(raw_irqs_disabled());
+
while (!need_resched()) {
void (*idle)(void);
@@ -178,7 +180,9 @@ void cpu_idle (void)
propagate_preempt_locks_value();
idle();
}
+ raw_local_irq_disable();
__schedule();
+ raw_local_irq_enable();
}
}
@@ -191,7 +195,7 @@ void cpu_idle (void)
*/
static void mwait_idle(void)
{
- local_irq_enable();
+ raw_local_irq_enable();
if (!need_resched()) {
set_thread_flag(TIF_POLLING_NRFLAG);
diff -Nurp -X linux-RT/Documentation/dontdiff linux-RT/arch/x86_64/kernel/signal.c linux-RT.mich/arch/x86_64/kernel/signal.c
--- linux-RT/arch/x86_64/kernel/signal.c 2005-06-07 14:05:16.000000000 +0200
+++ linux-RT.mich/arch/x86_64/kernel/signal.c 2005-06-08 18:53:24.000000000 +0200
@@ -411,6 +411,13 @@ int do_signal(struct pt_regs *regs, sigs
siginfo_t info;
int signr;
+#ifdef CONFIG_PREEMPT_RT
+ /*
+ * Fully-preemptible kernel does not need interrupts disabled:
+ */
+ raw_local_irq_enable();
+ preempt_check_resched();
+#endif
/*
* We want the common case to go fast, which
* is why we may in certain cases get here from
diff -Nurp -X linux-RT/Documentation/dontdiff linux-RT/arch/x86_64/kernel/smpboot.c linux-RT.mich/arch/x86_64/kernel/smpboot.c
--- linux-RT/arch/x86_64/kernel/smpboot.c 2005-06-07 14:05:16.000000000 +0200
+++ linux-RT.mich/arch/x86_64/kernel/smpboot.c 2005-06-08 19:23:36.000000000 +0200
@@ -207,7 +207,7 @@ static __cpuinit void sync_master(void *
go[MASTER] = 0;
- local_irq_save(flags);
+ raw_local_irq_save(flags);
{
for (i = 0; i < NUM_ROUNDS*NUM_ITERS; ++i) {
while (!go[MASTER])
@@ -216,7 +216,7 @@ static __cpuinit void sync_master(void *
rdtscll(go[SLAVE]);
}
}
- local_irq_restore(flags);
+ raw_local_irq_restore(flags);
}
/*
diff -Nurp -X linux-RT/Documentation/dontdiff linux-RT/arch/x86_64/kernel/smp.c linux-RT.mich/arch/x86_64/kernel/smp.c
--- linux-RT/arch/x86_64/kernel/smp.c 2005-06-08 19:28:13.000000000 +0200
+++ linux-RT.mich/arch/x86_64/kernel/smp.c 2005-06-08 19:10:50.000000000 +0200
@@ -359,9 +359,9 @@ void smp_stop_cpu(void)
* Remove this CPU:
*/
cpu_clear(smp_processor_id(), cpu_online_map);
- local_irq_disable();
+ raw_local_irq_disable();
disable_local_APIC();
- local_irq_enable();
+ raw_local_irq_enable();
}
static void smp_really_stop_cpu(void *dummy)
@@ -385,9 +385,9 @@ void smp_send_stop(void)
if (!nolock)
spin_unlock(&call_lock);
- local_irq_disable();
+ raw_local_irq_disable();
disable_local_APIC();
- local_irq_enable();
+ raw_local_irq_enable();
}
/*
diff -Nurp -X linux-RT/Documentation/dontdiff linux-RT/arch/x86_64/kernel/traps.c linux-RT.mich/arch/x86_64/kernel/traps.c
--- linux-RT/arch/x86_64/kernel/traps.c 2005-06-08 19:28:13.000000000 +0200
+++ linux-RT.mich/arch/x86_64/kernel/traps.c 2005-06-08 19:09:25.000000000 +0200
@@ -90,7 +90,7 @@ int register_die_notifier(struct notifie
static inline void conditional_sti(struct pt_regs *regs)
{
if (regs->eflags & X86_EFLAGS_IF)
- local_irq_enable();
+ raw_local_irq_enable();
}
static int kstack_depth_to_print = 10;
@@ -347,7 +347,7 @@ void oops_begin(void)
{
int cpu = safe_smp_processor_id();
/* racy, but better than risking deadlock. */
- local_irq_disable();
+ raw_local_irq_disable();
if (!spin_trylock(&die_lock)) {
if (cpu == die_owner)
/* nested oops. should stop eventually */;
diff -Nurp -X linux-RT/Documentation/dontdiff linux-RT/arch/x86_64/mm/fault.c linux-RT.mich/arch/x86_64/mm/fault.c
--- linux-RT/arch/x86_64/mm/fault.c 2005-06-08 19:28:13.000000000 +0200
+++ linux-RT.mich/arch/x86_64/mm/fault.c 2005-06-08 18:47:49.000000000 +0200
@@ -327,7 +327,7 @@ asmlinkage void do_page_fault(struct pt_
return;
if (likely(regs->eflags & X86_EFLAGS_IF))
- local_irq_enable();
+ raw_local_irq_enable();
if (unlikely(page_fault_trace))
printk("pagefault rip:%lx rsp:%lx cs:%lu ss:%lu address %lx error %lx\n",
diff -Nurp -X linux-RT/Documentation/dontdiff linux-RT/include/asm-x86_64/system.h linux-RT.mich/include/asm-x86_64/system.h
--- linux-RT/include/asm-x86_64/system.h 2005-06-08 19:28:13.000000000 +0200
+++ linux-RT.mich/include/asm-x86_64/system.h 2005-06-08 19:22:44.000000000 +0200
@@ -309,27 +309,31 @@ static inline unsigned long __cmpxchg(vo
#define warn_if_not_ulong(x) do { unsigned long foo; (void) (&(x) == &foo); } while (0)
/* interrupt control.. */
-#define local_save_flags(x) do { warn_if_not_ulong(x); __asm__ __volatile__("# save_flags \n\t pushfq ; popq %q0":"=g" (x): /* no input */ :"memory"); } while (0)
-#define local_irq_restore(x) __asm__ __volatile__("# restore_flags \n\t pushq %0 ; popfq": /* no output */ :"g" (x):"memory", "cc")
-#define local_irq_disable() __asm__ __volatile__("cli": : :"memory")
-#define local_irq_enable() __asm__ __volatile__("sti": : :"memory")
+#define __raw_local_save_flags(x) do { warn_if_not_ulong(x); __asm__ __volatile__("# save_flags \n\t pushfq ; popq %q0":"=g" (x): /* no input */ :"memory"); } while (0)
+#define __raw_local_irq_restore(x) __asm__ __volatile__("# restore_flags \n\t pushq %0 ; popfq": /* no output */ :"g" (x):"memory", "cc")
+#define __raw_local_irq_disable() __asm__ __volatile__("cli": : :"memory")
+#define __raw_local_irq_enable() __asm__ __volatile__("sti": : :"memory")
/* used in the idle loop; sti takes one instruction cycle to complete */
-#define safe_halt() __asm__ __volatile__("sti; hlt": : :"memory")
+#define __raw_safe_halt() __asm__ __volatile__("sti; hlt": : :"memory")
-#define irqs_disabled_flags(flags) \
-({ \
- !(flags & (1<<9)); \
+#define __raw_irqs_disabled_flags(flags) \
+({ \
+ !(flags & (1<<9)); \
})
-#define irqs_disabled() \
-({ \
- unsigned long flags; \
- local_save_flags(flags); \
- irqs_disabled_flags(flags); \
+#define __raw_irqs_disabled() \
+({ \
+ unsigned long flags; \
+ __raw_local_save_flags(flags); \
+ __raw_irqs_disabled_flags(flags); \
})
/* For spinlocks etc */
-#define local_irq_save(x) do { warn_if_not_ulong(x); __asm__ __volatile__("# local_irq_save \n\t pushfq ; popq %0 ; cli":"=g" (x): /* no input */ :"memory"); } while (0)
+#define __raw_local_irq_save(x) do { warn_if_not_ulong(x); __asm__ __volatile__("# local_irq_save \n\t pushfq ; popq %0 ; cli":"=g" (x): /* no input */ :"memory"); } while (0)
+
+#include <linux/rt_irq.h>
+
+#define safe_halt() do { local_irq_enable(); __asm__ __volatile__("hlt": : :"memory"); } while (0)
void cpu_idle_wait(void);