Re: [PATCH V3 1/4] acpi,pci,irq: reduce resource requirements

[Sinan Kaya <okaya@codeaurora.org>]

On 4/26/2016 2:36 PM, Bjorn Helgaas wrote:
> On Sun, Apr 17, 2016 at 01:36:53PM -0400, Sinan Kaya wrote:
>> Code has been redesigned to calculate penalty requirements on the fly. This
>> significantly simplifies the implementation and removes some of the init
>> calls from x86 architecture.
>>
>> Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
> 
> For all four patches:
> 
> Acked-by: Bjorn Helgaas <bhelgaas@google.com>

Thanks, can the HPE developers in CC test the series in order to avoid another revert? 

> 
>> ---
>>  drivers/acpi/pci_link.c | 97 ++++++++++++++++++++++++++++++++++---------------
>>  1 file changed, 68 insertions(+), 29 deletions(-)
>>
>> diff --git a/drivers/acpi/pci_link.c b/drivers/acpi/pci_link.c
>> index ededa90..cc0ba16 100644
>> --- a/drivers/acpi/pci_link.c
>> +++ b/drivers/acpi/pci_link.c
>> @@ -36,6 +36,7 @@
>>  #include <linux/mutex.h>
>>  #include <linux/slab.h>
>>  #include <linux/acpi.h>
>> +#include <linux/irq.h>
>>  
>>  #include "internal.h"
>>  
>> @@ -440,7 +441,6 @@ static int acpi_pci_link_set(struct acpi_pci_link *link, int irq)
>>  #define ACPI_MAX_IRQS		256
>>  #define ACPI_MAX_ISA_IRQ	16
>>  
>> -#define PIRQ_PENALTY_PCI_AVAILABLE	(0)
>>  #define PIRQ_PENALTY_PCI_POSSIBLE	(16*16)
>>  #define PIRQ_PENALTY_PCI_USING		(16*16*16)
>>  #define PIRQ_PENALTY_ISA_TYPICAL	(16*16*16*16)
>> @@ -457,9 +457,9 @@ static int acpi_irq_penalty[ACPI_MAX_IRQS] = {
>>  	PIRQ_PENALTY_ISA_TYPICAL,	/* IRQ6 */
>>  	PIRQ_PENALTY_ISA_TYPICAL,	/* IRQ7 parallel, spurious */
>>  	PIRQ_PENALTY_ISA_TYPICAL,	/* IRQ8 rtc, sometimes */
>> -	PIRQ_PENALTY_PCI_AVAILABLE,	/* IRQ9  PCI, often acpi */
>> -	PIRQ_PENALTY_PCI_AVAILABLE,	/* IRQ10 PCI */
>> -	PIRQ_PENALTY_PCI_AVAILABLE,	/* IRQ11 PCI */
>> +	0,				/* IRQ9  PCI, often acpi */
>> +	0,				/* IRQ10 PCI */
>> +	0,				/* IRQ11 PCI */
>>  	PIRQ_PENALTY_ISA_USED,		/* IRQ12 mouse */
>>  	PIRQ_PENALTY_ISA_USED,		/* IRQ13 fpe, sometimes */
>>  	PIRQ_PENALTY_ISA_USED,		/* IRQ14 ide0 */
>> @@ -467,6 +467,60 @@ static int acpi_irq_penalty[ACPI_MAX_IRQS] = {
>>  	/* >IRQ15 */
>>  };
>>  
>> +static int acpi_irq_pci_sharing_penalty(int irq)
>> +{
>> +	struct acpi_pci_link *link;
>> +	int penalty = 0;
>> +
>> +	list_for_each_entry(link, &acpi_link_list, list) {
>> +		/*
>> +		 * If a link is active, penalize its IRQ heavily
>> +		 * so we try to choose a different IRQ.
>> +		 */
>> +		if (link->irq.active && link->irq.active == irq)
>> +			penalty += PIRQ_PENALTY_PCI_USING;
>> +		else {
>> +			int i;
>> +
>> +			/*
>> +			 * If a link is inactive, penalize the IRQs it
>> +			 * might use, but not as severely.
>> +			 */
>> +			for (i = 0; i < link->irq.possible_count; i++)
>> +				if (link->irq.possible[i] == irq)
>> +					penalty += PIRQ_PENALTY_PCI_POSSIBLE /
>> +						link->irq.possible_count;
>> +		}
>> +	}
>> +
>> +	return penalty;
>> +}
>> +
>> +static int acpi_irq_get_penalty(int irq)
>> +{
>> +	int penalty = 0;
>> +
>> +	if (irq < ACPI_MAX_ISA_IRQ)
>> +		penalty += acpi_irq_penalty[irq];
>> +
>> +	/*
>> +	* Penalize IRQ used by ACPI SCI. If ACPI SCI pin attributes conflict
>> +	* with PCI IRQ attributes, mark ACPI SCI as ISA_ALWAYS so it won't be
>> +	* use for PCI IRQs.
>> +	*/
>> +	if (irq == acpi_gbl_FADT.sci_interrupt) {
>> +		u32 type = irq_get_trigger_type(irq) & IRQ_TYPE_SENSE_MASK;
>> +
>> +		if (type != IRQ_TYPE_LEVEL_LOW)
>> +			penalty += PIRQ_PENALTY_ISA_ALWAYS;
>> +		else
>> +			penalty += PIRQ_PENALTY_PCI_USING;
>> +	}
>> +
>> +	penalty += acpi_irq_pci_sharing_penalty(irq);
>> +	return penalty;
>> +}
>> +
>>  int __init acpi_irq_penalty_init(void)
>>  {
>>  	struct acpi_pci_link *link;
>> @@ -547,12 +601,12 @@ static int acpi_pci_link_allocate(struct acpi_pci_link *link)
>>  		 * the use of IRQs 9, 10, 11, and >15.
>>  		 */
>>  		for (i = (link->irq.possible_count - 1); i >= 0; i--) {
>> -			if (acpi_irq_penalty[irq] >
>> -			    acpi_irq_penalty[link->irq.possible[i]])
>> +			if (acpi_irq_get_penalty(irq) >
>> +			    acpi_irq_get_penalty(link->irq.possible[i]))
>>  				irq = link->irq.possible[i];
>>  		}
>>  	}
>> -	if (acpi_irq_penalty[irq] >= PIRQ_PENALTY_ISA_ALWAYS) {
>> +	if (acpi_irq_get_penalty(irq) >= PIRQ_PENALTY_ISA_ALWAYS) {
>>  		printk(KERN_ERR PREFIX "No IRQ available for %s [%s]. "
>>  			    "Try pci=noacpi or acpi=off\n",
>>  			    acpi_device_name(link->device),
>> @@ -568,7 +622,6 @@ static int acpi_pci_link_allocate(struct acpi_pci_link *link)
>>  			    acpi_device_bid(link->device));
>>  		return -ENODEV;
>>  	} else {
>> -		acpi_irq_penalty[link->irq.active] += PIRQ_PENALTY_PCI_USING;
>>  		printk(KERN_WARNING PREFIX "%s [%s] enabled at IRQ %d\n",
>>  		       acpi_device_name(link->device),
>>  		       acpi_device_bid(link->device), link->irq.active);
>> @@ -800,9 +853,10 @@ static int __init acpi_irq_penalty_update(char *str, int used)
>>  			continue;
>>  
>>  		if (used)
>> -			acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
>> +			acpi_irq_penalty[irq] = acpi_irq_get_penalty(irq) +
>> +				PIRQ_PENALTY_ISA_USED;
>>  		else
>> -			acpi_irq_penalty[irq] = PIRQ_PENALTY_PCI_AVAILABLE;
>> +			acpi_irq_penalty[irq] = 0;
>>  
>>  		if (retval != 2)	/* no next number */
>>  			break;
>> @@ -819,34 +873,19 @@ static int __init acpi_irq_penalty_update(char *str, int used)
>>   */
>>  void acpi_penalize_isa_irq(int irq, int active)
>>  {
>> -	if (irq >= 0 && irq < ARRAY_SIZE(acpi_irq_penalty)) {
>> -		if (active)
>> -			acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
>> -		else
>> -			acpi_irq_penalty[irq] += PIRQ_PENALTY_PCI_USING;
>> -	}
>> +	if (irq >= 0 && irq < ARRAY_SIZE(acpi_irq_penalty))
>> +		acpi_irq_penalty[irq] = acpi_irq_get_penalty(irq) +
>> +			active ? PIRQ_PENALTY_ISA_USED : PIRQ_PENALTY_PCI_USING;
>>  }
>>  
>>  bool acpi_isa_irq_available(int irq)
>>  {
>>  	return irq >= 0 && (irq >= ARRAY_SIZE(acpi_irq_penalty) ||
>> -			    acpi_irq_penalty[irq] < PIRQ_PENALTY_ISA_ALWAYS);
>> +		    acpi_irq_get_penalty(irq) < PIRQ_PENALTY_ISA_ALWAYS);
>>  }
>>  
>> -/*
>> - * Penalize IRQ used by ACPI SCI. If ACPI SCI pin attributes conflict with
>> - * PCI IRQ attributes, mark ACPI SCI as ISA_ALWAYS so it won't be use for
>> - * PCI IRQs.
>> - */
>>  void acpi_penalize_sci_irq(int irq, int trigger, int polarity)
>>  {
>> -	if (irq >= 0 && irq < ARRAY_SIZE(acpi_irq_penalty)) {
>> -		if (trigger != ACPI_MADT_TRIGGER_LEVEL ||
>> -		    polarity != ACPI_MADT_POLARITY_ACTIVE_LOW)
>> -			acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_ALWAYS;
>> -		else
>> -			acpi_irq_penalty[irq] += PIRQ_PENALTY_PCI_USING;
>> -	}
>>  }
>>  
>>  /*
>> -- 
>> 1.8.2.1
>>
>> --
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-- 
Sinan Kaya
Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project