diff mbox

[v5,07/12] x86/apic: Unify interrupt mode setup for UP system

Message ID 1fa26228fa94779d12d4089b83a43fe157b110fe.1498795030.git.douly.fnst@cn.fujitsu.com (mailing list archive)
State New, archived
Headers show

Commit Message

Dou Liyang June 30, 2017, 4:07 a.m. UTC
In UniProcessor kernel with UP_LATE_INIT=y, it enables and setups
interrupt delivery mode in up_late_init().

Unify it to apic_intr_mode_init(), remove APIC_init_uniprocessor().

Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
---
 arch/x86/include/asm/apic.h |  1 -
 arch/x86/kernel/apic/apic.c | 49 +++++++++------------------------------------
 2 files changed, 9 insertions(+), 41 deletions(-)

Comments

Thomas Gleixner July 2, 2017, 6:19 p.m. UTC | #1
On Fri, 30 Jun 2017, Dou Liyang wrote:
>  static inline int apic_force_enable(unsigned long addr)
> diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
> index 0601054..9bf7e95 100644
> --- a/arch/x86/kernel/apic/apic.c
> +++ b/arch/x86/kernel/apic/apic.c
> @@ -1198,6 +1198,10 @@ static int __init apic_intr_mode_select(int *upmode)
>  	}
>  #endif
>  
> +#ifdef CONFIG_UP_LATE_INIT
> +	*upmode = true;
> +#endif

This is really wrong. The upmode decision, which is required for calling
apic_bsp_setup() should not happen here, really. As I told you in the
previous patch, use the return code and then you can make further decisions
in apic_intr_mode_init().

And you do it there w/o any ifdeffery:

static void apic_intr_mode_init(void)
{
	bool upmode = IS_ENABLED(CONFIG_UP_LATE_INIT);

	switch (....) {
	case XXXX:
		upmode = true;
		....
	}
	apic_bsp_setup(upmode);
}

Thanks,

	tglx
Dou Liyang July 3, 2017, 2:34 a.m. UTC | #2
Hi Thomas,

At 07/03/2017 02:19 AM, Thomas Gleixner wrote:
> On Fri, 30 Jun 2017, Dou Liyang wrote:
>>  static inline int apic_force_enable(unsigned long addr)
>> diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
>> index 0601054..9bf7e95 100644
>> --- a/arch/x86/kernel/apic/apic.c
>> +++ b/arch/x86/kernel/apic/apic.c
>> @@ -1198,6 +1198,10 @@ static int __init apic_intr_mode_select(int *upmode)
>>  	}
>>  #endif
>>
>> +#ifdef CONFIG_UP_LATE_INIT
>> +	*upmode = true;
>> +#endif
>
> This is really wrong. The upmode decision, which is required for calling
> apic_bsp_setup() should not happen here, really. As I told you in the
> previous patch, use the return code and then you can make further decisions
> in apic_intr_mode_init().

Really thanks for your detail explaining, I learned more than i read
from books about the programming skill.

>
> And you do it there w/o any ifdeffery:
>
> static void apic_intr_mode_init(void)
> {
> 	bool upmode = IS_ENABLED(CONFIG_UP_LATE_INIT);
>
> 	switch (....) {
> 	case XXXX:
> 		upmode = true;
> 		....
> 	}
> 	apic_bsp_setup(upmode);
> }

This looks more beautiful than mine.  I will use it in the next version.

Thanks,

	dou.

>
> Thanks,
>
> 	tglx
>
>
>
diff mbox

Patch

diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h
index bfbf715..b35bbbf 100644
--- a/arch/x86/include/asm/apic.h
+++ b/arch/x86/include/asm/apic.h
@@ -144,7 +144,6 @@  void register_lapic_address(unsigned long address);
 extern void setup_boot_APIC_clock(void);
 extern void setup_secondary_APIC_clock(void);
 extern void lapic_update_tsc_freq(void);
-extern int APIC_init_uniprocessor(void);
 
 #ifdef CONFIG_X86_64
 static inline int apic_force_enable(unsigned long addr)
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 0601054..9bf7e95 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -1198,6 +1198,10 @@  static int __init apic_intr_mode_select(int *upmode)
 	}
 #endif
 
+#ifdef CONFIG_UP_LATE_INIT
+	*upmode = true;
+#endif
+
 	/* Check MP table or ACPI MADT configuration */
 	if (!smp_found_config) {
 		disable_ioapic_support();
@@ -2380,51 +2384,16 @@  void __init apic_bsp_setup(bool upmode)
 	setup_IO_APIC();
 }
 
-/*
- * This initializes the IO-APIC and APIC hardware if this is
- * a UP kernel.
- */
-int __init APIC_init_uniprocessor(void)
+#ifdef CONFIG_UP_LATE_INIT
+void __init up_late_init(void)
 {
-	if (disable_apic) {
-		pr_info("Apic disabled\n");
-		return -1;
-	}
-#ifdef CONFIG_X86_64
-	if (!boot_cpu_has(X86_FEATURE_APIC)) {
-		disable_apic = 1;
-		pr_info("Apic disabled by BIOS\n");
-		return -1;
-	}
-#else
-	if (!smp_found_config && !boot_cpu_has(X86_FEATURE_APIC))
-		return -1;
-
-	/*
-	 * Complain if the BIOS pretends there is one.
-	 */
-	if (!boot_cpu_has(X86_FEATURE_APIC) &&
-	    APIC_INTEGRATED(boot_cpu_apic_version)) {
-		pr_err("BIOS bug, local APIC 0x%x not detected!...\n",
-			boot_cpu_physical_apicid);
-		return -1;
-	}
-#endif
+	apic_intr_mode_init();
 
-	if (!smp_found_config)
-		disable_ioapic_support();
+	if (apic_intr_mode == APIC_PIC)
+		return;
 
-	default_setup_apic_routing();
-	apic_bsp_setup(true);
 	/* Setup local timer */
 	x86_init.timers.setup_percpu_clockev();
-	return 0;
-}
-
-#ifdef CONFIG_UP_LATE_INIT
-void __init up_late_init(void)
-{
-	APIC_init_uniprocessor();
 }
 #endif