/**
* irq_alloc_descs - allocate and initialize a range of irq descriptors
* @irq: Allocate for specific irq number if irq >= 0
* @from: Start the search from this irq number
* @cnt: Number of consecutive irqs to allocate.
* @node: Preferred node on which the irq descriptor should be allocated
* @owner: Owning module (can be NULL)
*
* Returns the first irq number or error code
*/
int __ref
__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
struct module *owner)
{
int start, ret;
if (!cnt)
return -EINVAL;
if (irq >= 0) {
if (from > irq)
return -EINVAL;
from = irq;
} else {
/*
* For interrupts which are freely allocated the
* architecture can force a lower bound to the @from
* argument. x86 uses this to exclude the GSI space.
*/
from = arch_dynirq_lower_bound(from);
}
mutex_lock(&sparse_irq_lock);
start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
from, cnt, 0);
ret = -EEXIST;
if (irq >=0 && start != irq)
goto err;
if (start + cnt > nr_irqs) {
ret = irq_expand_nr_irqs(start + cnt);
if (ret)
goto err;
}
bitmap_set(allocated_irqs, start, cnt);
mutex_unlock(&sparse_irq_lock);
return alloc_descs(start, cnt, node, owner);
err:
mutex_unlock(&sparse_irq_lock);
return ret;
}
/**
* irq_alloc_descs - allocate and initialize a range of irq descriptors
* @irq: Allocate for specific irq number if irq >= 0
* @from: Start the search from this irq number
* @cnt: Number of consecutive irqs to allocate.
* @node: Preferred node on which the irq descriptor should be allocated
* @owner: Owning module (can be NULL)
*
* Returns the first irq number or error code
*/
int __ref
__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
struct module *owner)
{
int start, ret;
if (!cnt)
return -EINVAL;
if (irq >= 0) {
if (from > irq)
return -EINVAL;
from = irq;
}
mutex_lock(&sparse_irq_lock);
start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
from, cnt, 0);
ret = -EEXIST;
if (irq >=0 && start != irq)
goto err;
if (start + cnt > nr_irqs) {
ret = irq_expand_nr_irqs(start + cnt);
if (ret)
goto err;
}
bitmap_set(allocated_irqs, start, cnt);
mutex_unlock(&sparse_irq_lock);
return alloc_descs(start, cnt, node, owner);
err:
mutex_unlock(&sparse_irq_lock);
return ret;
}
// ARM10C 20141115
// irq_start: -1, 16, gic_irqs: 144, numa_node_id(): 0, THIS_MODULE: ((struct module *)0)
// ARM10C 20141213
// first_irq: 160, 160, size: 256, 0, THIS_MODULE: ((struct module *)0)
int __ref
__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
struct module *owner)
{
int start, ret;
// cnt: 144
// cnt: 256
if (!cnt)
return -EINVAL;
// irq: -1
// irq: 160
if (irq >= 0) {
// from: 160, irq: 160
if (from > irq)
return -EINVAL;
// from: 160, irq: 160
from = irq;
// from: 160
}
mutex_lock(&sparse_irq_lock);
// sparse_irq_lock을 이용한 mutex lock 수행
// sparse_irq_lock을 이용한 mutex lock 수행
// IRQ_BITMAP_BITS: 8212, from: 16, cnt: 144
// bitmap_find_next_zero_area(allocated_irqs, 8212, 16, 144, 0): 16
// IRQ_BITMAP_BITS: 8212, from: 160, cnt: 256
// bitmap_find_next_zero_area(allocated_irqs, 8212, 160, 256, 0): 160
start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
from, cnt, 0);
// start: 16
// start: 160
// EEXIST: 17
// EEXIST: 17
ret = -EEXIST;
// ret: -17
// ret: -17
// irq: -1, start: 16
// irq: 160, start: 160
if (irq >=0 && start != irq)
goto err;
// start: 16, cnt: 144, nr_irqs: 16
// start: 160, cnt: 256, nr_irqs: 160
if (start + cnt > nr_irqs) {
// start: 16, cnt: 144
// irq_expand_nr_irqs(160): 0
// start: 160, cnt: 256
// irq_expand_nr_irqs(416): 0
ret = irq_expand_nr_irqs(start + cnt);
// ret: 0
// ret: 0
// irq_expand_nr_irqs(160)에서 한일:
// 전역변수 nr_irqs 값을 160으로 갱신
// irq_expand_nr_irqs(416)에서 한일:
// 전역변수 nr_irqs 값을 416으로 갱신
// ret: 0
// ret: 0
if (ret)
goto err;
}
// start: 16, cnt: 144
// start: 160, cnt: 256
bitmap_set(allocated_irqs, start, cnt);
// bitmap_set(16, 144)에서 한일:
// allocated_irqs 의 16 bit 부터 144 bit 만큼을 1로 set
// bitmap_set(160, 256)에서 한일:
// allocated_irqs 의 160 bit 부터 256 bit 만큼을 1로 set
mutex_unlock(&sparse_irq_lock);
// sparse_irq_lock을 이용한 mutex unlock 수행
// sparse_irq_lock을 이용한 mutex unlock 수행
// start: 16, cnt: 144, node: 0, owner: NULL
// alloc_descs(16, 144, 0, NULL): 16
// start: 160, cnt: 256, node: 0, owner: NULL
// alloc_descs(160, 256, 0, NULL): 160
return alloc_descs(start, cnt, node, owner);
// return 16
// return 160
/*
// alloc_descs(16)에서 한일:
// struct irq_desc의 자료 구조크기 만큼 160개의 메모리를 할당 받아
// radix tree 구조로 구성
//
// irq 16 ~ 159를 위한 struct irq_desc 메모리를 할당 받아 초기화 수행
// (kmem_cache#28-oX (irq 16...159))->lock 을 이용한 spinlock 초기화 수행
// (kmem_cache#28-oX (irq 16...159))->status_use_accessors: 0xc00
// (kmem_cache#28-oX (irq 16...159))->handle_irq: handle_bad_irq
// (kmem_cache#28-oX (irq 16...159))->depth: 1
// (kmem_cache#28-oX (irq 16...159))->irq_count: 0
// (kmem_cache#28-oX (irq 16...159))->irqs_unhandled: 0
// (kmem_cache#28-oX (irq 16...159))->name: NULL
// (kmem_cache#28-oX (irq 16...159))->owner: null
// (kmem_cache#28-oX (irq 16...159))->kstat_irqs: pcp 4 byte 공간
// [pcp0...3] (kmem_cache#28-oX (irq 16...159))->kstat_irqs: 0
// (kmem_cache#28-oX (irq 16...159))->irq_data.irq: 16...159
// (kmem_cache#28-oX (irq 16...159))->irq_data.chip: &no_irq_chip
// (kmem_cache#28-oX (irq 16...159))->irq_data.chip_data: NULL
// (kmem_cache#28-oX (irq 16...159))->irq_data.handler_data: NULL
// (kmem_cache#28-oX (irq 16...159))->irq_data.msi_desc: NULL
// (kmem_cache#28-oX (irq 16...159))->irq_data.state_use_accessors: 0x10000
// (kmem_cache#28-oX (irq 16...159))->irq_data.node: 0
// (kmem_cache#28-oX (irq 16...159))->irq_data.affinity.bits[0]: 0xF
//
// radix tree의 root node: &irq_desc_tree 값을 변경
// (&irq_desc_tree)->rnode: kmem_cache#20-o1 (RADIX_LSB: 1)
// (&irq_desc_tree)->height: 2
//
// (kmem_cache#20-o1)->height: 2
// (kmem_cache#20-o1)->count: 3
// (kmem_cache#20-o1)->parent: NULL
// (kmem_cache#20-o1)->slots[0]: kmem_cache#20-o0 (radix height 1 관리 주소)
// (kmem_cache#20-o1)->slots[1]: kmem_cache#20-o2 (radix height 1 관리 주소)
// (kmem_cache#20-o1)->slots[2]: kmem_cache#20-o3 (radix height 1 관리 주소)
//
// (kmem_cache#20-o0)->height: 1
// (kmem_cache#20-o0)->count: 64
// (kmem_cache#20-o0)->parent: kmem_cache#20-o1 (RADIX_LSB: 1)
// (kmem_cache#20-o0)->slots[0...63]: kmem_cache#28-oX (irq 0...63)
//
// (kmem_cache#20-o2)->height: 1
// (kmem_cache#20-o2)->count: 64
// (kmem_cache#20-o2)->parent: kmem_cache#20-o1 (RADIX_LSB: 1)
// (kmem_cache#20-o2)->slots[0...63]: kmem_cache#28-oX (irq 63...127)
//
// (kmem_cache#20-o3)->height: 1
// (kmem_cache#20-o3)->count: 32
// (kmem_cache#20-o3)->parent: kmem_cache#20-o1 (RADIX_LSB: 1)
// (kmem_cache#20-o3)->slots[0...63]: kmem_cache#28-oX (irq 127...159)
//
// (&irq_desc_tree)->rnode --> +-----------------------+
// | radix_tree_node |
// | (kmem_cache#20-o1) |
// +-----------------------+
// | height: 2 | count: 3 |
// +-----------------------+
// | radix_tree_node 0 ~ 2 |
// +-----------------------+
// / | \
// slot: 0 / slot: 1 | \ slot: 2
// +-----------------------+ +-----------------------+ +-----------------------+
// | radix_tree_node | | radix_tree_node | | radix_tree_node |
// | (kmem_cache#20-o0) | | (kmem_cache#20-o2) | | (kmem_cache#20-o3) |
// +-----------------------+ +-----------------------+ +-----------------------+
// | height: 1 | count: 64 | | height: 1 | count: 64 | | height: 1 | count: 32 |
// +-----------------------+ +-----------------------+ +-----------------------+
// | irq 0 ~ 63 | | irq 64 ~ 127 | | irq 128 ~ 159 |
// +-----------------------+ +-----------------------+ +-----------------------+
*/
/*
// alloc_descs(160)에서 한일:
// struct irq_desc의 자료 구조크기 만큼 256개의 메모리를 할당 받아
// radix tree 구조로 구성
//
// irq 160 ~ 415를 위한 struct irq_desc 메모리를 할당 받아 초기화 수행
// (kmem_cache#28-oX (irq 160...415))->lock 을 이용한 spinlock 초기화 수행
// (kmem_cache#28-oX (irq 160...415))->status_use_accessors: 0xc00
// (kmem_cache#28-oX (irq 160...415))->handle_irq: handle_bad_irq
// (kmem_cache#28-oX (irq 160...415))->depth: 1
// (kmem_cache#28-oX (irq 160...415))->irq_count: 0
// (kmem_cache#28-oX (irq 160...415))->irqs_unhandled: 0
// (kmem_cache#28-oX (irq 160...415))->name: NULL
// (kmem_cache#28-oX (irq 160...415))->owner: null
// (kmem_cache#28-oX (irq 160...415))->kstat_irqs: pcp 4 byte 공간
// [pcp0...3] (kmem_cache#28-oX (irq 160...415))->kstat_irqs: 0
// (kmem_cache#28-oX (irq 160...415))->irq_data.irq: 16...415
// (kmem_cache#28-oX (irq 160...415))->irq_data.chip: &no_irq_chip
// (kmem_cache#28-oX (irq 160...415))->irq_data.chip_data: NULL
// (kmem_cache#28-oX (irq 160...415))->irq_data.handler_data: NULL
// (kmem_cache#28-oX (irq 160...415))->irq_data.msi_desc: NULL
// (kmem_cache#28-oX (irq 160...415))->irq_data.state_use_accessors: 0x10000
// (kmem_cache#28-oX (irq 160...415))->irq_data.node: 0
// (kmem_cache#28-oX (irq 160...415))->irq_data.affinity.bits[0]: 0xF
//
// radix tree의 root node: &irq_desc_tree 값을 변경
// (&irq_desc_tree)->rnode: kmem_cache#20-o1 (RADIX_LSB: 1)
// (&irq_desc_tree)->height: 2
//
// (kmem_cache#20-o1)->height: 2
// (kmem_cache#20-o1)->count: 7
// (kmem_cache#20-o1)->parent: NULL
// (kmem_cache#20-o1)->slots[0]: kmem_cache#20-o0 (radix height 1 관리 주소)
// (kmem_cache#20-o1)->slots[1]: kmem_cache#20-o2 (radix height 1 관리 주소)
// (kmem_cache#20-o1)->slots[2]: kmem_cache#20-o3 (radix height 1 관리 주소)
// (kmem_cache#20-o1)->slots[3]: kmem_cache#20-o4 (radix height 1 관리 주소)
// (kmem_cache#20-o1)->slots[4]: kmem_cache#20-o5 (radix height 1 관리 주소)
// (kmem_cache#20-o1)->slots[5]: kmem_cache#20-o6 (radix height 1 관리 주소)
// (kmem_cache#20-o1)->slots[6]: kmem_cache#20-o7 (radix height 1 관리 주소)
//
// (kmem_cache#20-o0)->height: 1
// (kmem_cache#20-o0)->count: 64
// (kmem_cache#20-o0)->parent: kmem_cache#20-o1 (RADIX_LSB: 1)
// (kmem_cache#20-o0)->slots[0...63]: kmem_cache#28-oX (irq 0...63)
//
// (kmem_cache#20-o2)->height: 1
// (kmem_cache#20-o2)->count: 64
// (kmem_cache#20-o2)->parent: kmem_cache#20-o1 (RADIX_LSB: 1)
// (kmem_cache#20-o2)->slots[0...63]: kmem_cache#28-oX (irq 63...127)
//
// (kmem_cache#20-o3)->height: 1
// (kmem_cache#20-o3)->count: 64
// (kmem_cache#20-o3)->parent: kmem_cache#20-o1 (RADIX_LSB: 1)
// (kmem_cache#20-o3)->slots[0...63]: kmem_cache#28-oX (irq 127...191)
//
// (kmem_cache#20-o4)->height: 1
// (kmem_cache#20-o4)->count: 64
// (kmem_cache#20-o4)->parent: kmem_cache#20-o1 (RADIX_LSB: 1)
// (kmem_cache#20-o4)->slots[0...63]: kmem_cache#28-oX (irq 192...255)
//
// (kmem_cache#20-o5)->height: 1
// (kmem_cache#20-o5)->count: 64
// (kmem_cache#20-o5)->parent: kmem_cache#20-o1 (RADIX_LSB: 1)
// (kmem_cache#20-o5)->slots[0...63]: kmem_cache#28-oX (irq 256...319)
//
// (kmem_cache#20-o6)->height: 1
// (kmem_cache#20-o6)->count: 64
// (kmem_cache#20-o6)->parent: kmem_cache#20-o1 (RADIX_LSB: 1)
// (kmem_cache#20-o6)->slots[0...63]: kmem_cache#28-oX (irq 320...383)
//
// (kmem_cache#20-o7)->height: 1
// (kmem_cache#20-o7)->count: 32
// (kmem_cache#20-o7)->parent: kmem_cache#20-o1 (RADIX_LSB: 1)
// (kmem_cache#20-o7)->slots[0...31]: kmem_cache#28-oX (irq 384...415)
//
// (&irq_desc_tree)->rnode --> +-----------------------+
// | radix_tree_node |
// | (kmem_cache#20-o1) |
// +-----------------------+
// | height: 2 | count: 7 |
// +-----------------------+
// | radix_tree_node 0 ~ 6 | \
// / +-----------------------+ \ \
// / / | | \ \ \ㅡㅡㅡㅡㅡㅡㅡㅡㅡㅡㅡㅡㅡ
// slot: 0 / | slot: 1 | | | \ slot: 2 |
// +-----------------------+ | +-----------------------+ | +-----------------------+ |
// | radix_tree_node | | | radix_tree_node | | | radix_tree_node | |
// | (kmem_cache#20-o0) | | | (kmem_cache#20-o2) | | | (kmem_cache#20-o3) | |
// +-----------------------+ | +-----------------------+ | +-----------------------+ |
// | height: 1 | count: 64 | | | height: 1 | count: 64 | | | height: 1 | count: 64 | |
// +-----------------------+ | +-----------------------+ | +-----------------------+ |
// | irq 0 ~ 63 | | | irq 64 ~ 127 | | | irq 128 ~ 191 | |
// +-----------------------+ | +-----------------------+ | +-----------------------+ |
// / | \ |
// slot: 3 / slot: 4 | \ slot: 5 \ slot: 6
// +-----------------------+ +-----------------------+ +-----------------------+ +-----------------------+
// | radix_tree_node | | radix_tree_node | | radix_tree_node | | radix_tree_node |
// | (kmem_cache#20-o4) | | (kmem_cache#20-o5) | | (kmem_cache#20-o6) | | (kmem_cache#20-o7) |
// +-----------------------+ +-----------------------+ +-----------------------+ +-----------------------+
// | height: 1 | count: 64 | | height: 1 | count: 64 | | height: 1 | count: 64 | | height: 1 | count: 32 |
// +-----------------------+ +-----------------------+ +-----------------------+ +-----------------------+
// | irq 192 ~ 255 | | irq 256 ~ 319 | | irq 320 ~ 383 | | irq 384 ~ 415 |
// +-----------------------+ +-----------------------+ +-----------------------+ +-----------------------+
*/
err:
mutex_unlock(&sparse_irq_lock);
return ret;
}
