Re: [patch] irq: use config_enabled(SMP) checks to cleanupirq_set_affinity() for UP
From: Suresh Siddha
Date: Thu Jun 07 2012 - 18:34:44 EST
On Thu, 2012-06-07 at 09:03 -0400, Paul Gortmaker wrote:
> On 12-06-06 07:29 PM, Suresh Siddha wrote:
> > On Ingo's request, re-basing the previous version
> > (http://marc.info/?l=linux-kernel&m=133667389223282) to the latest -tip
> > tree. Thanks.
> > ---
> > From: Suresh Siddha <suresh.b.siddha@xxxxxxxxx>
> > Subject: irq: use config_enabled(CONFIG_SMP) checks to cleanup irq_set_affinity() for UP
> >
> > Use config_enabled(CONFIG_SMP) checks for cleaning up the ifdef CONFIG_SMP
> > around irq_set_affinity routines in io_apic and irq_remapping subsystems.
> >
> > Signed-off-by: Suresh Siddha <suresh.b.siddha@xxxxxxxxx>
> > ---
> > arch/x86/kernel/apic/io_apic.c | 173 +++++++++++++++++------------------
>
> What was the necessity of the giant code block move here?
Patch was moving the SMP affinity routines out of the existing "#ifdef
CONFIG_SMP" section and adding config_enabled(CONFIG_SMP) inside those
routines, making those routines simple null stubs for !SMP and retaining
those routines with no runtime checks for SMP kernels.
> It wasn't obvious to me, and it isn't called out in the
> commit log. Presumably some used before defined issue, but
> it would be nice to have that called out, so a person isn't
> wondering if instead it was an offhand error.
Updated with more elaborate changelog!
---
From: Suresh Siddha <suresh.b.siddha@xxxxxxxxx>
Subject: irq: use config_enabled(CONFIG_SMP) checks to cleanup irq_set_affinity() for UP
Move the set_affinity routines out of the #ifdef CONFIG_SMP sections and
use config_enabled(CONFIG_SMP) checks inside those routines. Thus
making those routines simple null stubs for !CONFIG_SMP and retaining those
routines with no additional runtime overhead for CONFIG_SMP kernels.
Cleans up the ifdef CONFIG_SMP in and around routines related to
irq_set_affinity in io_apic and irq_remapping subsystems.
Signed-off-by: Suresh Siddha <suresh.b.siddha@xxxxxxxxx>
---
arch/x86/kernel/apic/io_apic.c | 173 +++++++++++++++++------------------
drivers/iommu/intel_irq_remapping.c | 7 +-
drivers/iommu/irq_remapping.c | 5 +-
drivers/iommu/irq_remapping.h | 2 -
include/linux/irq.h | 2 -
5 files changed, 88 insertions(+), 101 deletions(-)
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 9a71f21..f246b78 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2206,72 +2206,6 @@ void send_cleanup_vector(struct irq_cfg *cfg)
cfg->move_in_progress = 0;
}
-static void __target_IO_APIC_irq(unsigned int irq, unsigned int dest, struct irq_cfg *cfg)
-{
- int apic, pin;
- struct irq_pin_list *entry;
- u8 vector = cfg->vector;
-
- for_each_irq_pin(entry, cfg->irq_2_pin) {
- unsigned int reg;
-
- apic = entry->apic;
- pin = entry->pin;
- /*
- * With interrupt-remapping, destination information comes
- * from interrupt-remapping table entry.
- */
- if (!irq_remapped(cfg))
- io_apic_write(apic, 0x11 + pin*2, dest);
- reg = io_apic_read(apic, 0x10 + pin*2);
- reg &= ~IO_APIC_REDIR_VECTOR_MASK;
- reg |= vector;
- io_apic_modify(apic, 0x10 + pin*2, reg);
- }
-}
-
-/*
- * Either sets data->affinity to a valid value, and returns
- * ->cpu_mask_to_apicid of that in dest_id, or returns -1 and
- * leaves data->affinity untouched.
- */
-int __ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
- unsigned int *dest_id)
-{
- struct irq_cfg *cfg = data->chip_data;
-
- if (!cpumask_intersects(mask, cpu_online_mask))
- return -1;
-
- if (assign_irq_vector(data->irq, data->chip_data, mask))
- return -1;
-
- cpumask_copy(data->affinity, mask);
-
- *dest_id = apic->cpu_mask_to_apicid_and(mask, cfg->domain);
- return 0;
-}
-
-static int
-ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
- bool force)
-{
- unsigned int dest, irq = data->irq;
- unsigned long flags;
- int ret;
-
- raw_spin_lock_irqsave(&ioapic_lock, flags);
- ret = __ioapic_set_affinity(data, mask, &dest);
- if (!ret) {
- /* Only the high 8 bits are valid. */
- dest = SET_APIC_LOGICAL_ID(dest);
- __target_IO_APIC_irq(irq, dest, data->chip_data);
- ret = IRQ_SET_MASK_OK_NOCOPY;
- }
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
- return ret;
-}
-
asmlinkage void smp_irq_move_cleanup_interrupt(void)
{
unsigned vector, me;
@@ -2359,6 +2293,77 @@ void irq_force_complete_move(int irq)
static inline void irq_complete_move(struct irq_cfg *cfg) { }
#endif
+static void __target_IO_APIC_irq(unsigned int irq, unsigned int dest, struct irq_cfg *cfg)
+{
+ int apic, pin;
+ struct irq_pin_list *entry;
+ u8 vector = cfg->vector;
+
+ for_each_irq_pin(entry, cfg->irq_2_pin) {
+ unsigned int reg;
+
+ apic = entry->apic;
+ pin = entry->pin;
+ /*
+ * With interrupt-remapping, destination information comes
+ * from interrupt-remapping table entry.
+ */
+ if (!irq_remapped(cfg))
+ io_apic_write(apic, 0x11 + pin*2, dest);
+ reg = io_apic_read(apic, 0x10 + pin*2);
+ reg &= ~IO_APIC_REDIR_VECTOR_MASK;
+ reg |= vector;
+ io_apic_modify(apic, 0x10 + pin*2, reg);
+ }
+}
+
+/*
+ * Either sets data->affinity to a valid value, and returns
+ * ->cpu_mask_to_apicid of that in dest_id, or returns -1 and
+ * leaves data->affinity untouched.
+ */
+int __ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
+ unsigned int *dest_id)
+{
+ struct irq_cfg *cfg = data->chip_data;
+
+ if (!config_enabled(CONFIG_SMP))
+ return -1;
+
+ if (!cpumask_intersects(mask, cpu_online_mask))
+ return -1;
+
+ if (assign_irq_vector(data->irq, data->chip_data, mask))
+ return -1;
+
+ cpumask_copy(data->affinity, mask);
+
+ *dest_id = apic->cpu_mask_to_apicid_and(mask, cfg->domain);
+ return 0;
+}
+
+static int
+ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
+ bool force)
+{
+ unsigned int dest, irq = data->irq;
+ unsigned long flags;
+ int ret;
+
+ if (!config_enabled(CONFIG_SMP))
+ return -1;
+
+ raw_spin_lock_irqsave(&ioapic_lock, flags);
+ ret = __ioapic_set_affinity(data, mask, &dest);
+ if (!ret) {
+ /* Only the high 8 bits are valid. */
+ dest = SET_APIC_LOGICAL_ID(dest);
+ __target_IO_APIC_irq(irq, dest, data->chip_data);
+ }
+ raw_spin_unlock_irqrestore(&ioapic_lock, flags);
+ return ret;
+}
+
static void ack_apic_edge(struct irq_data *data)
{
irq_complete_move(data->chip_data);
@@ -2538,9 +2543,7 @@ static void irq_remap_modify_chip_defaults(struct irq_chip *chip)
chip->irq_ack = ir_ack_apic_edge;
chip->irq_eoi = ir_ack_apic_level;
-#ifdef CONFIG_SMP
chip->irq_set_affinity = set_remapped_irq_affinity;
-#endif
}
#endif /* CONFIG_IRQ_REMAP */
@@ -2551,9 +2554,7 @@ static struct irq_chip ioapic_chip __read_mostly = {
.irq_unmask = unmask_ioapic_irq,
.irq_ack = ack_apic_edge,
.irq_eoi = ack_apic_level,
-#ifdef CONFIG_SMP
.irq_set_affinity = ioapic_set_affinity,
-#endif
.irq_retrigger = ioapic_retrigger_irq,
};
@@ -3069,7 +3070,6 @@ static int msi_compose_msg(struct pci_dev *pdev, unsigned int irq,
return err;
}
-#ifdef CONFIG_SMP
static int
msi_set_affinity(struct irq_data *data, const struct cpumask *mask, bool force)
{
@@ -3077,6 +3077,9 @@ msi_set_affinity(struct irq_data *data, const struct cpumask *mask, bool force)
struct msi_msg msg;
unsigned int dest;
+ if (!config_enabled(CONFIG_SMP))
+ return -1;
+
if (__ioapic_set_affinity(data, mask, &dest))
return -1;
@@ -3091,7 +3094,6 @@ msi_set_affinity(struct irq_data *data, const struct cpumask *mask, bool force)
return IRQ_SET_MASK_OK_NOCOPY;
}
-#endif /* CONFIG_SMP */
/*
* IRQ Chip for MSI PCI/PCI-X/PCI-Express Devices,
@@ -3102,9 +3104,7 @@ static struct irq_chip msi_chip = {
.irq_unmask = unmask_msi_irq,
.irq_mask = mask_msi_irq,
.irq_ack = ack_apic_edge,
-#ifdef CONFIG_SMP
.irq_set_affinity = msi_set_affinity,
-#endif
.irq_retrigger = ioapic_retrigger_irq,
};
@@ -3189,7 +3189,6 @@ void native_teardown_msi_irq(unsigned int irq)
}
#ifdef CONFIG_DMAR_TABLE
-#ifdef CONFIG_SMP
static int
dmar_msi_set_affinity(struct irq_data *data, const struct cpumask *mask,
bool force)
@@ -3198,6 +3197,9 @@ dmar_msi_set_affinity(struct irq_data *data, const struct cpumask *mask,
unsigned int dest, irq = data->irq;
struct msi_msg msg;
+ if (!config_enabled(CONFIG_SMP))
+ return -1;
+
if (__ioapic_set_affinity(data, mask, &dest))
return -1;
@@ -3214,16 +3216,12 @@ dmar_msi_set_affinity(struct irq_data *data, const struct cpumask *mask,
return IRQ_SET_MASK_OK_NOCOPY;
}
-#endif /* CONFIG_SMP */
-
static struct irq_chip dmar_msi_type = {
.name = "DMAR_MSI",
.irq_unmask = dmar_msi_unmask,
.irq_mask = dmar_msi_mask,
.irq_ack = ack_apic_edge,
-#ifdef CONFIG_SMP
.irq_set_affinity = dmar_msi_set_affinity,
-#endif
.irq_retrigger = ioapic_retrigger_irq,
};
@@ -3244,7 +3242,6 @@ int arch_setup_dmar_msi(unsigned int irq)
#ifdef CONFIG_HPET_TIMER
-#ifdef CONFIG_SMP
static int hpet_msi_set_affinity(struct irq_data *data,
const struct cpumask *mask, bool force)
{
@@ -3252,6 +3249,9 @@ static int hpet_msi_set_affinity(struct irq_data *data,
struct msi_msg msg;
unsigned int dest;
+ if (!config_enabled(CONFIG_SMP))
+ return -1;
+
if (__ioapic_set_affinity(data, mask, &dest))
return -1;
@@ -3267,16 +3267,12 @@ static int hpet_msi_set_affinity(struct irq_data *data,
return IRQ_SET_MASK_OK_NOCOPY;
}
-#endif /* CONFIG_SMP */
-
static struct irq_chip hpet_msi_type = {
.name = "HPET_MSI",
.irq_unmask = hpet_msi_unmask,
.irq_mask = hpet_msi_mask,
.irq_ack = ack_apic_edge,
-#ifdef CONFIG_SMP
.irq_set_affinity = hpet_msi_set_affinity,
-#endif
.irq_retrigger = ioapic_retrigger_irq,
};
@@ -3311,8 +3307,6 @@ int arch_setup_hpet_msi(unsigned int irq, unsigned int id)
*/
#ifdef CONFIG_HT_IRQ
-#ifdef CONFIG_SMP
-
static void target_ht_irq(unsigned int irq, unsigned int dest, u8 vector)
{
struct ht_irq_msg msg;
@@ -3333,6 +3327,9 @@ ht_set_affinity(struct irq_data *data, const struct cpumask *mask, bool force)
struct irq_cfg *cfg = data->chip_data;
unsigned int dest;
+ if (!config_enabled(CONFIG_SMP))
+ return -1;
+
if (__ioapic_set_affinity(data, mask, &dest))
return -1;
@@ -3340,16 +3337,12 @@ ht_set_affinity(struct irq_data *data, const struct cpumask *mask, bool force)
return IRQ_SET_MASK_OK_NOCOPY;
}
-#endif
-
static struct irq_chip ht_irq_chip = {
.name = "PCI-HT",
.irq_mask = mask_ht_irq,
.irq_unmask = unmask_ht_irq,
.irq_ack = ack_apic_edge,
-#ifdef CONFIG_SMP
.irq_set_affinity = ht_set_affinity,
-#endif
.irq_retrigger = ioapic_retrigger_irq,
};
diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index 6d34706..b3481cf 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -902,7 +902,6 @@ static int intel_setup_ioapic_entry(int irq,
return 0;
}
-#ifdef CONFIG_SMP
/*
* Migrate the IO-APIC irq in the presence of intr-remapping.
*
@@ -925,6 +924,9 @@ intel_ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
unsigned int dest, irq = data->irq;
struct irte irte;
+ if (!config_enabled(CONFIG_SMP))
+ return -EINVAL;
+
if (!cpumask_intersects(mask, cpu_online_mask))
return -EINVAL;
@@ -956,7 +958,6 @@ intel_ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
cpumask_copy(data->affinity, mask);
return 0;
}
-#endif
static void intel_compose_msi_msg(struct pci_dev *pdev,
unsigned int irq, unsigned int dest,
@@ -1058,9 +1059,7 @@ struct irq_remap_ops intel_irq_remap_ops = {
.reenable = reenable_irq_remapping,
.enable_faulting = enable_drhd_fault_handling,
.setup_ioapic_entry = intel_setup_ioapic_entry,
-#ifdef CONFIG_SMP
.set_affinity = intel_ioapic_set_affinity,
-#endif
.free_irq = free_irte,
.compose_msi_msg = intel_compose_msi_msg,
.msi_alloc_irq = intel_msi_alloc_irq,
diff --git a/drivers/iommu/irq_remapping.c b/drivers/iommu/irq_remapping.c
index 40cda8e..1d29b1c 100644
--- a/drivers/iommu/irq_remapping.c
+++ b/drivers/iommu/irq_remapping.c
@@ -111,16 +111,15 @@ int setup_ioapic_remapped_entry(int irq,
vector, attr);
}
-#ifdef CONFIG_SMP
int set_remapped_irq_affinity(struct irq_data *data, const struct cpumask *mask,
bool force)
{
- if (!remap_ops || !remap_ops->set_affinity)
+ if (!config_enabled(CONFIG_SMP) || !remap_ops ||
+ !remap_ops->set_affinity)
return 0;
return remap_ops->set_affinity(data, mask, force);
}
-#endif
void free_remapped_irq(int irq)
{
diff --git a/drivers/iommu/irq_remapping.h b/drivers/iommu/irq_remapping.h
index be9d729..b12974c 100644
--- a/drivers/iommu/irq_remapping.h
+++ b/drivers/iommu/irq_remapping.h
@@ -59,11 +59,9 @@ struct irq_remap_ops {
unsigned int, int,
struct io_apic_irq_attr *);
-#ifdef CONFIG_SMP
/* Set the CPU affinity of a remapped interrupt */
int (*set_affinity)(struct irq_data *data, const struct cpumask *mask,
bool force);
-#endif
/* Free an IRQ */
int (*free_irq)(int);
diff --git a/include/linux/irq.h b/include/linux/irq.h
index 61f5cec..47a937c 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -150,9 +150,7 @@ struct irq_data {
void *handler_data;
void *chip_data;
struct msi_desc *msi_desc;
-#ifdef CONFIG_SMP
cpumask_var_t affinity;
-#endif
};
/*
--
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