[patch 04/15] x86/ioapic: Use guard() for locking where applicable

Thomas Gleixner
2024-08-02T16:15:45Z

KISS rules!

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/kernel/apic/io_apic.c | 192 +++++++++++++----------------------------
1 file changed, 64 insertions(+), 128 deletions(-)

--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -296,14 +296,8 @@ static struct IO_APIC_route_entry __ioap

static struct IO_APIC_route_entry ioapic_read_entry(int apic, int pin)
{
- struct IO_APIC_route_entry entry;
- unsigned long flags;
-
- raw_spin_lock_irqsave(&ioapic_lock, flags);
- entry = __ioapic_read_entry(apic, pin);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
-
- return entry;
+ guard(raw_spinlock_irqsave)(&ioapic_lock);
+ return __ioapic_read_entry(apic, pin);
}

/*
@@ -320,11 +314,8 @@ static void __ioapic_write_entry(int api

static void ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e)
{
- unsigned long flags;
-
- raw_spin_lock_irqsave(&ioapic_lock, flags);
+ guard(raw_spinlock_irqsave)(&ioapic_lock);
__ioapic_write_entry(apic, pin, e);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
}

/*
@@ -335,12 +326,10 @@ static void ioapic_write_entry(int apic,
static void ioapic_mask_entry(int apic, int pin)
{
struct IO_APIC_route_entry e = { .masked = true };
- unsigned long flags;

- raw_spin_lock_irqsave(&ioapic_lock, flags);
+ guard(raw_spinlock_irqsave)(&ioapic_lock);
io_apic_write(apic, 0x10 + 2*pin, e.w1);
io_apic_write(apic, 0x11 + 2*pin, e.w2);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
}

/*
@@ -433,11 +422,9 @@ static void io_apic_sync(struct irq_pin_
static void mask_ioapic_irq(struct irq_data *irq_data)
{
struct mp_chip_data *data = irq_data->chip_data;
- unsigned long flags;

- raw_spin_lock_irqsave(&ioapic_lock, flags);
+ guard(raw_spinlock_irqsave)(&ioapic_lock);
io_apic_modify_irq(data, true, &io_apic_sync);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
}

static void __unmask_ioapic(struct mp_chip_data *data)
@@ -448,11 +435,9 @@ static void __unmask_ioapic(struct mp_ch
static void unmask_ioapic_irq(struct irq_data *irq_data)
{
struct mp_chip_data *data = irq_data->chip_data;
- unsigned long flags;

- raw_spin_lock_irqsave(&ioapic_lock, flags);
+ guard(raw_spinlock_irqsave)(&ioapic_lock);
__unmask_ioapic(data);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
}

/*
@@ -497,13 +482,11 @@ static void __eoi_ioapic_pin(int apic, i

static void eoi_ioapic_pin(int vector, struct mp_chip_data *data)
{
- unsigned long flags;
struct irq_pin_list *entry;

- raw_spin_lock_irqsave(&ioapic_lock, flags);
+ guard(raw_spinlock_irqsave)(&ioapic_lock);
for_each_irq_pin(entry, data->irq_2_pin)
__eoi_ioapic_pin(entry->apic, entry->pin, vector);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
}

static void clear_IO_APIC_pin(unsigned int apic, unsigned int pin)
@@ -526,8 +509,6 @@ static void clear_IO_APIC_pin(unsigned i
}

if (entry.irr) {
- unsigned long flags;
-
/*
* Make sure the trigger mode is set to level. Explicit EOI
* doesn't clear the remote-IRR if the trigger mode is not
@@ -537,9 +518,8 @@ static void clear_IO_APIC_pin(unsigned i
entry.is_level = true;
ioapic_write_entry(apic, pin, entry);
}
- raw_spin_lock_irqsave(&ioapic_lock, flags);
+ guard(raw_spinlock_irqsave)(&ioapic_lock);
__eoi_ioapic_pin(apic, pin, entry.vector);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
}

/*
@@ -1033,7 +1013,7 @@ static int mp_map_pin_to_irq(u32 gsi, in
return -EINVAL;
}

- mutex_lock(&ioapic_mutex);
+ guard(mutex)(&ioapic_mutex);
if (!(flags & IOAPIC_MAP_ALLOC)) {
if (!legacy) {
irq = irq_find_mapping(domain, pin);
@@ -1054,8 +1034,6 @@ static int mp_map_pin_to_irq(u32 gsi, in
data->count++;
}
}
- mutex_unlock(&ioapic_mutex);
-
return irq;
}

@@ -1120,10 +1098,9 @@ void mp_unmap_irq(int irq)
if (!data || data->isa_irq)
return;

- mutex_lock(&ioapic_mutex);
+ guard(mutex)(&ioapic_mutex);
if (--data->count == 0)
irq_domain_free_irqs(irq, 1);
- mutex_unlock(&ioapic_mutex);
}

/*
@@ -1251,16 +1228,15 @@ static void __init print_IO_APIC(int ioa
union IO_APIC_reg_01 reg_01;
union IO_APIC_reg_02 reg_02;
union IO_APIC_reg_03 reg_03;
- unsigned long flags;

- raw_spin_lock_irqsave(&ioapic_lock, flags);
- reg_00.raw = io_apic_read(ioapic_idx, 0);
- reg_01.raw = io_apic_read(ioapic_idx, 1);
- if (reg_01.bits.version >= 0x10)
- reg_02.raw = io_apic_read(ioapic_idx, 2);
- if (reg_01.bits.version >= 0x20)
- reg_03.raw = io_apic_read(ioapic_idx, 3);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
+ scoped_guard (raw_spinlock_irqsave, &ioapic_lock) {
+ reg_00.raw = io_apic_read(ioapic_idx, 0);
+ reg_01.raw = io_apic_read(ioapic_idx, 1);
+ if (reg_01.bits.version >= 0x10)
+ reg_02.raw = io_apic_read(ioapic_idx, 2);
+ if (reg_01.bits.version >= 0x20)
+ reg_03.raw = io_apic_read(ioapic_idx, 3);
+ }

printk(KERN_DEBUG "IO APIC #%d......\n", mpc_ioapic_id(ioapic_idx));
printk(KERN_DEBUG ".... register #00: %08X\n", reg_00.raw);
@@ -1451,7 +1427,6 @@ static void __init setup_ioapic_ids_from
const u32 broadcast_id = 0xF;
union IO_APIC_reg_00 reg_00;
unsigned char old_id;
- unsigned long flags;
int ioapic_idx, i;

/*
@@ -1465,9 +1440,8 @@ static void __init setup_ioapic_ids_from
*/
for_each_ioapic(ioapic_idx) {
/* Read the register 0 value */
- raw_spin_lock_irqsave(&ioapic_lock, flags);
- reg_00.raw = io_apic_read(ioapic_idx, 0);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
+ scoped_guard (raw_spinlock_irqsave, &ioapic_lock)
+ reg_00.raw = io_apic_read(ioapic_idx, 0);

old_id = mpc_ioapic_id(ioapic_idx);

@@ -1522,16 +1496,11 @@ static void __init setup_ioapic_ids_from
mpc_ioapic_id(ioapic_idx));

reg_00.bits.ID = mpc_ioapic_id(ioapic_idx);
- raw_spin_lock_irqsave(&ioapic_lock, flags);
- io_apic_write(ioapic_idx, 0, reg_00.raw);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
-
- /*
- * Sanity check
- */
- raw_spin_lock_irqsave(&ioapic_lock, flags);
- reg_00.raw = io_apic_read(ioapic_idx, 0);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
+ scoped_guard (raw_spinlock_irqsave, &ioapic_lock) {
+ io_apic_write(ioapic_idx, 0, reg_00.raw);
+ reg_00.raw = io_apic_read(ioapic_idx, 0);
+ }
+ /* Sanity check */
if (reg_00.bits.ID != mpc_ioapic_id(ioapic_idx))
pr_cont("could not set ID!\n");
else
@@ -1661,17 +1630,14 @@ static int __init timer_irq_works(void)
static unsigned int startup_ioapic_irq(struct irq_data *data)
{
int was_pending = 0, irq = data->irq;
- unsigned long flags;

- raw_spin_lock_irqsave(&ioapic_lock, flags);
+ guard(raw_spinlock_irqsave)(&ioapic_lock);
if (irq < nr_legacy_irqs()) {
legacy_pic->mask(irq);
if (legacy_pic->irq_pending(irq))
was_pending = 1;
}
__unmask_ioapic(data->chip_data);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
-
return was_pending;
}

@@ -1681,9 +1647,8 @@ atomic_t irq_mis_count;
static bool io_apic_level_ack_pending(struct mp_chip_data *data)
{
struct irq_pin_list *entry;
- unsigned long flags;

- raw_spin_lock_irqsave(&ioapic_lock, flags);
+ guard(raw_spinlock_irqsave)(&ioapic_lock);
for_each_irq_pin(entry, data->irq_2_pin) {
struct IO_APIC_route_entry e;
int pin;
@@ -1691,13 +1656,9 @@ static bool io_apic_level_ack_pending(st
pin = entry->pin;
e.w1 = io_apic_read(entry->apic, 0x10 + pin*2);
/* Is the remote IRR bit set? */
- if (e.irr) {
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
+ if (e.irr)
return true;
- }
}
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
-
return false;
}

@@ -1898,18 +1859,16 @@ static void ioapic_configure_entry(struc
__ioapic_write_entry(entry->apic, entry->pin, mpd->entry);
}

-static int ioapic_set_affinity(struct irq_data *irq_data,
- const struct cpumask *mask, bool force)
+static int ioapic_set_affinity(struct irq_data *irq_data, const struct cpumask *mask, bool force)
{
struct irq_data *parent = irq_data->parent_data;
- unsigned long flags;
int ret;

ret = parent->chip->irq_set_affinity(parent, mask, force);
- raw_spin_lock_irqsave(&ioapic_lock, flags);
+
+ guard(raw_spinlock_irqsave)(&ioapic_lock);
if (ret >= 0 && ret != IRQ_SET_MASK_OK_DONE)
ioapic_configure_entry(irq_data);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);

return ret;
}
@@ -1928,9 +1887,8 @@ static int ioapic_set_affinity(struct ir
*
* Verify that the corresponding Remote-IRR bits are clear.
*/
-static int ioapic_irq_get_chip_state(struct irq_data *irqd,
- enum irqchip_irq_state which,
- bool *state)
+static int ioapic_irq_get_chip_state(struct irq_data *irqd, enum irqchip_irq_state which,
+ bool *state)
{
struct mp_chip_data *mcd = irqd->chip_data;
struct IO_APIC_route_entry rentry;
@@ -1940,7 +1898,8 @@ static int ioapic_irq_get_chip_state(str
return -EINVAL;

*state = false;
- raw_spin_lock(&ioapic_lock);
+
+ guard(raw_spinlock)(&ioapic_lock);
for_each_irq_pin(p, mcd->irq_2_pin) {
rentry = __ioapic_read_entry(p->apic, p->pin);
/*
@@ -1954,7 +1913,6 @@ static int ioapic_irq_get_chip_state(str
break;
}
}
- raw_spin_unlock(&ioapic_lock);
return 0;
}

@@ -2129,9 +2087,8 @@ static int __init mp_alloc_timer_irq(int
ioapic_set_alloc_attr(&info, NUMA_NO_NODE, 0, 0);
info.devid = mpc_ioapic_id(ioapic);
info.ioapic.pin = pin;
- mutex_lock(&ioapic_mutex);
+ guard(mutex)(&ioapic_mutex);
irq = alloc_isa_irq_from_domain(domain, 0, ioapic, pin, &info);
- mutex_unlock(&ioapic_mutex);
}

return irq;
@@ -2142,8 +2099,6 @@ static int __init mp_alloc_timer_irq(int
* a wide range of boards and BIOS bugs. Fortunately only the timer IRQ
* is so screwy. Thanks to Brian Perkins for testing/hacking this beast
* fanatically on his truly buggy board.
- *
- * FIXME: really need to revamp this for all platforms.
*/
static inline void __init check_timer(void)
{
@@ -2404,16 +2359,14 @@ void __init setup_IO_APIC(void)

static void resume_ioapic_id(int ioapic_idx)
{
- unsigned long flags;
union IO_APIC_reg_00 reg_00;

- raw_spin_lock_irqsave(&ioapic_lock, flags);
+ guard(raw_spinlock_irqsave)(&ioapic_lock);
reg_00.raw = io_apic_read(ioapic_idx, 0);
if (reg_00.bits.ID != mpc_ioapic_id(ioapic_idx)) {
reg_00.bits.ID = mpc_ioapic_id(ioapic_idx);
io_apic_write(ioapic_idx, 0, reg_00.raw);
}
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
}

static void ioapic_resume(void)
@@ -2443,15 +2396,13 @@ device_initcall(ioapic_init_ops);
static int io_apic_get_redir_entries(int ioapic)
{
union IO_APIC_reg_01 reg_01;
- unsigned long flags;

- raw_spin_lock_irqsave(&ioapic_lock, flags);
+ guard(raw_spinlock_irqsave)(&ioapic_lock);
reg_01.raw = io_apic_read(ioapic, 1);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);

- /* The register returns the maximum index redir index
- * supported, which is one less than the total number of redir
- * entries.
+ /*
+ * The register returns the maximum index redir index supported,
+ * which is one less than the total number of redir entries.
*/
return reg_01.bits.entries + 1;
}
@@ -2481,16 +2432,14 @@ static int io_apic_get_unique_id(int ioa
static DECLARE_BITMAP(apic_id_map, MAX_LOCAL_APIC);
const u32 broadcast_id = 0xF;
union IO_APIC_reg_00 reg_00;
- unsigned long flags;
int i = 0;

/* Initialize the ID map */
if (bitmap_empty(apic_id_map, MAX_LOCAL_APIC))
copy_phys_cpu_present_map(apic_id_map);

- raw_spin_lock_irqsave(&ioapic_lock, flags);
- reg_00.raw = io_apic_read(ioapic, 0);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
+ scoped_guard (raw_spinlock_irqsave, &ioapic_lock)
+ reg_00.raw = io_apic_read(ioapic, 0);

if (apic_id >= broadcast_id) {
pr_warn("IOAPIC[%d]: Invalid apic_id %d, trying %d\n",
@@ -2517,21 +2466,19 @@ static int io_apic_get_unique_id(int ioa
if (reg_00.bits.ID != apic_id) {
reg_00.bits.ID = apic_id;

- raw_spin_lock_irqsave(&ioapic_lock, flags);
- io_apic_write(ioapic, 0, reg_00.raw);
- reg_00.raw = io_apic_read(ioapic, 0);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
+ scoped_guard (raw_spinlock_irqsave, &ioapic_lock) {
+ io_apic_write(ioapic, 0, reg_00.raw);
+ reg_00.raw = io_apic_read(ioapic, 0);
+ }

/* Sanity check */
if (reg_00.bits.ID != apic_id) {
- pr_err("IOAPIC[%d]: Unable to change apic_id!\n",
- ioapic);
+ pr_err("IOAPIC[%d]: Unable to change apic_id!\n", ioapic);
return -1;
}
}

- apic_printk(APIC_VERBOSE, KERN_INFO
- "IOAPIC[%d]: Assigned apic_id %d\n", ioapic, apic_id);
+ apic_printk(APIC_VERBOSE, KERN_INFO "IOAPIC[%d]: Assigned apic_id %d\n", ioapic, apic_id);

return apic_id;
}
@@ -2547,7 +2494,6 @@ static u8 io_apic_unique_id(int idx, u8
{
union IO_APIC_reg_00 reg_00;
DECLARE_BITMAP(used, 256);
- unsigned long flags;
u8 new_id;
int i;

@@ -2563,26 +2509,23 @@ static u8 io_apic_unique_id(int idx, u8
* Read the current id from the ioapic and keep it if
* available.
*/
- raw_spin_lock_irqsave(&ioapic_lock, flags);
- reg_00.raw = io_apic_read(idx, 0);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
+ scoped_guard (raw_spinlock_irqsave, &ioapic_lock)
+ reg_00.raw = io_apic_read(idx, 0);
+
new_id = reg_00.bits.ID;
if (!test_bit(new_id, used)) {
- apic_printk(APIC_VERBOSE, KERN_INFO
- "IOAPIC[%d]: Using reg apic_id %d instead of %d\n",
- idx, new_id, id);
+ apic_printk(APIC_VERBOSE, KERN_INFO "IOAPIC[%d]: Using reg apic_id %d instead of %d\n",
+ idx, new_id, id);
return new_id;
}

- /*
- * Get the next free id and write it to the ioapic.
- */
+ /* Get the next free id and write it to the ioapic. */
new_id = find_first_zero_bit(used, 256);
reg_00.bits.ID = new_id;
- raw_spin_lock_irqsave(&ioapic_lock, flags);
- io_apic_write(idx, 0, reg_00.raw);
- reg_00.raw = io_apic_read(idx, 0);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
+ scoped_guard (raw_spinlock_irqsave, &ioapic_lock) {
+ io_apic_write(idx, 0, reg_00.raw);
+ reg_00.raw = io_apic_read(idx, 0);
+ }
/* Sanity check */
BUG_ON(reg_00.bits.ID != new_id);

@@ -2592,12 +2535,10 @@ static u8 io_apic_unique_id(int idx, u8

static int io_apic_get_version(int ioapic)
{
- union IO_APIC_reg_01 reg_01;
- unsigned long flags;
+ union IO_APIC_reg_01 reg_01;

- raw_spin_lock_irqsave(&ioapic_lock, flags);
+ guard(raw_spinlock_irqsave)(&ioapic_lock);
reg_01.raw = io_apic_read(ioapic, 1);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);

return reg_01.bits.version;
}
@@ -3050,22 +2991,17 @@ void mp_irqdomain_free(struct irq_domain
irq_data = irq_domain_get_irq_data(domain, virq);
if (irq_data && irq_data->chip_data) {
data = irq_data->chip_data;
- __remove_pin_from_irq(data, mp_irqdomain_ioapic_idx(domain),
- (int)irq_data->hwirq);
+ __remove_pin_from_irq(data, mp_irqdomain_ioapic_idx(domain), (int)irq_data->hwirq);
WARN_ON(!list_empty(&data->irq_2_pin));
kfree(irq_data->chip_data);
}
irq_domain_free_irqs_top(domain, virq, nr_irqs);
}

-int mp_irqdomain_activate(struct irq_domain *domain,
- struct irq_data *irq_data, bool reserve)
+int mp_irqdomain_activate(struct irq_domain *domain, struct irq_data *irq_data, bool reserve)
{
- unsigned long flags;
-
- raw_spin_lock_irqsave(&ioapic_lock, flags);
+ guard(raw_spinlock_irqsave)(&ioapic_lock);
ioapic_configure_entry(irq_data);
- raw_spin_unlock_irqrestore(&ioapic_lock, flags);
return 0;
}