hv: pirq: refactor vector allocation/free

This commit refactors vector allocation/free codes, two functions are
defined to help alloc/free vectors for an irq:
- uint32_t alloc_irq_vector(uint32_t irq)
  - alloc a free vector (0x20 ~ 0xDF), and bind it to irq, for legacy irqs
    and static mapped irqs, vector has been allocated and bind, so just
    check the mapping correctness;
  - return: valid vector on success, VECTOR_INVALID on failure.

- void free_irq_vector(uint32_t irq)
  - free vector allocated via alloc_irq_vector(), for legacy irqs and static
    mapped irqs, nothing need to do.

Signed-off-by: Yan, Like <like.yan@intel.com>
Acked-by: Anthony Xu <anthony.xu@intel.com>
This commit is contained in:
Yan, Like 2018-08-16 19:40:46 +08:00 committed by lijinxia
parent 1bf2fc342a
commit 2c044e0c4e
4 changed files with 94 additions and 147 deletions

View File

@ -371,8 +371,8 @@ void setup_ioapic_irq(void)
* for legacy irq, reserved vector and never free
*/
if (gsi < NR_LEGACY_IRQ) {
vr = irq_desc_alloc_vector(gsi);
if (vr > NR_MAX_VECTOR) {
vr = alloc_irq_vector(gsi);
if (vr == VECTOR_INVALID) {
pr_err("failed to alloc VR");
gsi++;
continue;

View File

@ -46,22 +46,6 @@ static void init_irq_desc(void)
}
}
/*
* find available vector VECTOR_DYNAMIC_START ~ VECTOR_DYNAMIC_END
*/
static uint32_t find_available_vector()
{
uint32_t i;
/* TODO: vector lock required */
for (i = VECTOR_DYNAMIC_START; i <= VECTOR_DYNAMIC_END; i++) {
if (vector_to_irq[i] == IRQ_INVALID) {
return i;
}
}
return VECTOR_INVALID;
}
/*
* alloc an free irq if req_irq is IRQ_INVALID, or else set assigned
* return: irq num on success, IRQ_INVALID on failure
@ -119,35 +103,62 @@ void free_irq_num(uint32_t irq)
}
}
/* need lock protection before use */
static void local_irq_desc_set_vector(uint32_t irq, uint32_t vr)
/*
* alloc an vectror and bind it to irq
* for legacy_irq (irq num < 16) and static mapped ones, do nothing
* if mapping is correct.
* retval: valid vector num on susccess, VECTOR_INVALID on failure.
*/
uint32_t alloc_irq_vector(uint32_t irq)
{
uint32_t vr;
struct irq_desc *desc;
desc = &irq_desc_array[irq];
vector_to_irq[vr] = irq;
desc->vector = vr;
}
/* lock version of set vector */
static void irq_desc_set_vector(uint32_t irq, uint32_t vr)
{
uint64_t rflags;
struct irq_desc *desc;
if (irq >= NR_IRQS) {
pr_err("invalid irq[%u] to alloc vector", irq);
return VECTOR_INVALID;
}
desc = &irq_desc_array[irq];
spinlock_irqsave_obtain(&desc->lock, &rflags);
vector_to_irq[vr] = irq;
desc->vector = vr;
spinlock_irqrestore_release(&desc->lock, rflags);
if (desc->vector != VECTOR_INVALID) {
if (vector_to_irq[desc->vector] == irq) {
/* statically binded */
vr = desc->vector;
} else {
pr_err("[%s] irq[%u]:vector[%u] mismatch",
__func__, irq, desc->vector);
vr = VECTOR_INVALID;
}
} else {
/* alloc a vector between:
* VECTOR_DYNAMIC_START ~ VECTOR_DYNAMC_END
*/
spinlock_irqsave_obtain(&irq_alloc_spinlock, &rflags);
for (vr = VECTOR_DYNAMIC_START;
vr <= VECTOR_DYNAMIC_END; vr++) {
if (vector_to_irq[vr] == IRQ_INVALID) {
desc->vector = vr;
vector_to_irq[vr] = irq;
break;
}
}
vr = (vr > VECTOR_DYNAMIC_END) ? VECTOR_INVALID : vr;
spinlock_irqrestore_release(&irq_alloc_spinlock, rflags);
}
return vr;
}
/* used with holding lock outside */
static void _irq_desc_free_vector(uint32_t irq)
/* free the vector allocated via alloc_irq_vector() */
void free_irq_vector(uint32_t irq)
{
struct irq_desc *desc;
uint32_t vr;
uint16_t pcpu_id;
uint64_t rflags;
if (irq >= NR_IRQS) {
return;
@ -155,18 +166,20 @@ static void _irq_desc_free_vector(uint32_t irq)
desc = &irq_desc_array[irq];
if ((irq < NR_LEGACY_IRQ) || (desc->vector >= VECTOR_FIXED_START)) {
/* do nothing for LEGACY_IRQ and static allocated ones */
return;
}
spinlock_irqsave_obtain(&irq_alloc_spinlock, &rflags);
vr = desc->vector;
desc->used = IRQ_NOT_ASSIGNED;
desc->vector = VECTOR_INVALID;
vr &= NR_MAX_VECTOR;
if (vector_to_irq[vr] == irq) {
vector_to_irq[vr] = IRQ_INVALID;
}
for (pcpu_id = 0U; pcpu_id < phys_cpu_num; pcpu_id++) {
per_cpu(irq_count, pcpu_id)[irq] = 0UL;
}
spinlock_irqrestore_release(&irq_alloc_spinlock, rflags);
}
static void disable_pic_irq(void)
@ -175,6 +188,28 @@ static void disable_pic_irq(void)
pio_write8(0xffU, 0x21U);
}
/*
* There are four cases as to irq/vector allocation:
* case 1: req_irq = IRQ_INVALID
* caller did not know which irq to use, and want system to
* allocate available irq for it. These irq are in range:
* nr_gsi ~ NR_IRQS
* an irq will be allocated and a vector will be assigned to this
* irq automatically.
* case 2: req_irq >= NR_LAGACY_IRQ and irq < nr_gsi
* caller want to add device ISR handler into ioapic pins.
* a vector will automatically assigned.
* case 3: req_irq >=0 and req_irq < NR_LEGACY_IRQ
* caller want to add device ISR handler into ioapic pins, which
* is a legacy irq, vector already reserved.
* Nothing to do in this case.
* case 4: irq with speical type (not from IOAPIC/MSI)
* These irq value are pre-defined for Timer, IPI, Spurious etc,
* which is listed in irq_static_mappings[].
* Nothing to do in this case.
*
* return value: valid irq (>=0) on success, otherwise errno (< 0).
*/
int32_t request_irq(uint32_t req_irq,
irq_action_t action_fn,
void *priv_data)
@ -183,65 +218,32 @@ int32_t request_irq(uint32_t req_irq,
uint32_t irq, vector;
uint64_t rflags;
/* ======================================================
* This is low level ISR handler registering function
* case: irq = IRQ_INVALID
* caller did not know which irq to use, and want system to
* allocate available irq for it. These irq are in range:
* nr_gsi ~ NR_IRQS
* a irq will be allocated and the vector will be assigned to this
* irq automatically.
*
* case: irq >=0 and irq < nr_gsi
* caller want to add device ISR handler into ioapic pins.
* two kind of devices: legacy device and PCI device with INTx
* a vector will automatically assigned.
*
* case: irq with speical type (not from IOAPIC/MSI)
* These irq value are pre-defined for Timer, IPI, Spurious etc
* vectors are pre-defined also
*
* return value: pinned irq and assigned vector for this irq.
* caller can use this irq to enable/disable/mask/unmask interrupt
* and if this irq is for:
* GSI legacy: nothing to do for legacy irq, already initialized
* GSI other: need to progam PCI INTx to match this irq pin
* MSI: caller need program vector to PCI device
*
* =====================================================
*/
irq = alloc_irq_num(req_irq);
if (irq == IRQ_INVALID) {
pr_err("[%s] invalid irq num", __func__);
return -EINVAL;
}
desc = &irq_desc_array[irq];
if (desc->irq_handler == NULL) {
desc->irq_handler = common_handler_edge;
}
vector = desc->vector;
if (vector >= VECTOR_FIXED_START &&
vector <= VECTOR_FIXED_END) {
irq_desc_set_vector(irq, vector);
} else if (vector > NR_MAX_VECTOR) {
irq_desc_alloc_vector(irq);
}
if (desc->vector == VECTOR_INVALID) {
pr_err("the input vector is not correct");
vector = alloc_irq_vector(irq);
if (vector == VECTOR_INVALID) {
pr_err("[%s] failed to alloc vector for irq %u",
__func__, irq);
free_irq_num(irq);
return -EINVAL;
}
desc = &irq_desc_array[irq];
spinlock_irqsave_obtain(&desc->lock, &rflags);
if (desc->irq_handler == NULL) {
desc->irq_handler = common_handler_edge;
}
if (desc->action == NULL) {
spinlock_irqsave_obtain(&desc->lock, &rflags);
desc->priv_data = priv_data;
desc->action = action_fn;
spinlock_irqrestore_release(&desc->lock, rflags);
} else {
spinlock_irqrestore_release(&desc->lock, rflags);
pr_err("%s: request irq(%u) vr(%u) failed,\
already requested", __func__,
irq, irq_to_vector(irq));
@ -254,58 +256,6 @@ int32_t request_irq(uint32_t req_irq,
return (int32_t)irq;
}
/* it is safe to call irq_desc_alloc_vector multiple times*/
uint32_t irq_desc_alloc_vector(uint32_t irq)
{
uint32_t vr = VECTOR_INVALID;
uint64_t rflags;
struct irq_desc *desc;
/* irq should be always available at this time */
if (irq >= NR_IRQS) {
return VECTOR_INVALID;
}
desc = &irq_desc_array[irq];
spinlock_irqsave_obtain(&desc->lock, &rflags);
if (desc->vector != VECTOR_INVALID) {
/* already allocated a vector */
goto OUT;
}
/* FLAT mode, a irq connected to every cpu's same vector */
vr = find_available_vector();
if (vr > NR_MAX_VECTOR) {
pr_err("no vector found for irq[%d]", irq);
goto OUT;
}
local_irq_desc_set_vector(irq, vr);
OUT:
spinlock_irqrestore_release(&desc->lock, rflags);
return vr;
}
void irq_desc_try_free_vector(uint32_t irq)
{
uint64_t rflags;
struct irq_desc *desc;
/* legacy irq's vector is reserved and should not be freed */
if ((irq >= NR_IRQS) || (irq < NR_LEGACY_IRQ)) {
return;
}
desc = &irq_desc_array[irq];
spinlock_irqsave_obtain(&desc->lock, &rflags);
if (desc->action == NULL) {
_irq_desc_free_vector(irq);
}
spinlock_irqrestore_release(&desc->lock, rflags);
}
uint32_t irq_to_vector(uint32_t irq)
{
if (irq < NR_IRQS) {
@ -527,14 +477,13 @@ void free_irq(uint32_t irq)
dev_dbg(ACRN_DBG_IRQ, "[%s] irq%d vr:0x%x",
__func__, irq, irq_to_vector(irq));
spinlock_irqsave_obtain(&desc->lock, &rflags);
free_irq_vector(irq);
free_irq_num(irq);
spinlock_irqsave_obtain(&desc->lock, &rflags);
desc->action = NULL;
desc->priv_data = NULL;
spinlock_irqrestore_release(&desc->lock, rflags);
irq_desc_try_free_vector(desc->irq);
free_irq_num(irq);
}
#ifdef HV_DEBUG

View File

@ -75,6 +75,9 @@ typedef void (*spurious_handler_t)(uint32_t vector);
extern spurious_handler_t spurious_handler;
uint32_t alloc_irq_num(uint32_t req_irq);
uint32_t alloc_irq_vector(uint32_t irq);
uint32_t irq_to_vector(uint32_t irq);
/*
* Some MSI message definitions

View File

@ -34,11 +34,6 @@ struct irq_desc {
spinlock_t lock;
};
uint32_t irq_desc_alloc_vector(uint32_t irq);
void irq_desc_try_free_vector(uint32_t irq);
uint32_t irq_to_vector(uint32_t irq);
int32_t request_irq(uint32_t irq,
irq_action_t action_fn,
void *priv_data);