dmaengine: Move dma_channel_rebalance() infrastructure up in code

So it can be called by a release function which is needed higher up in
the code. No functional changes intended.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Link: https://lore.kernel.org/r/20191216190120.21374-4-logang@deltatee.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This commit is contained in:
Logan Gunthorpe 2019-12-16 12:01:18 -07:00 committed by Vinod Koul
parent 686607106f
commit 11a0fd2b3b

View File

@ -164,6 +164,150 @@ static struct class dma_devclass = {
/* --- client and device registration --- */ /* --- client and device registration --- */
/**
* dma_cap_mask_all - enable iteration over all operation types
*/
static dma_cap_mask_t dma_cap_mask_all;
/**
* dma_chan_tbl_ent - tracks channel allocations per core/operation
* @chan - associated channel for this entry
*/
struct dma_chan_tbl_ent {
struct dma_chan *chan;
};
/**
* channel_table - percpu lookup table for memory-to-memory offload providers
*/
static struct dma_chan_tbl_ent __percpu *channel_table[DMA_TX_TYPE_END];
static int __init dma_channel_table_init(void)
{
enum dma_transaction_type cap;
int err = 0;
bitmap_fill(dma_cap_mask_all.bits, DMA_TX_TYPE_END);
/* 'interrupt', 'private', and 'slave' are channel capabilities,
* but are not associated with an operation so they do not need
* an entry in the channel_table
*/
clear_bit(DMA_INTERRUPT, dma_cap_mask_all.bits);
clear_bit(DMA_PRIVATE, dma_cap_mask_all.bits);
clear_bit(DMA_SLAVE, dma_cap_mask_all.bits);
for_each_dma_cap_mask(cap, dma_cap_mask_all) {
channel_table[cap] = alloc_percpu(struct dma_chan_tbl_ent);
if (!channel_table[cap]) {
err = -ENOMEM;
break;
}
}
if (err) {
pr_err("initialization failure\n");
for_each_dma_cap_mask(cap, dma_cap_mask_all)
free_percpu(channel_table[cap]);
}
return err;
}
arch_initcall(dma_channel_table_init);
/**
* dma_chan_is_local - returns true if the channel is in the same numa-node as
* the cpu
*/
static bool dma_chan_is_local(struct dma_chan *chan, int cpu)
{
int node = dev_to_node(chan->device->dev);
return node == NUMA_NO_NODE ||
cpumask_test_cpu(cpu, cpumask_of_node(node));
}
/**
* min_chan - returns the channel with min count and in the same numa-node as
* the cpu
* @cap: capability to match
* @cpu: cpu index which the channel should be close to
*
* If some channels are close to the given cpu, the one with the lowest
* reference count is returned. Otherwise, cpu is ignored and only the
* reference count is taken into account.
* Must be called under dma_list_mutex.
*/
static struct dma_chan *min_chan(enum dma_transaction_type cap, int cpu)
{
struct dma_device *device;
struct dma_chan *chan;
struct dma_chan *min = NULL;
struct dma_chan *localmin = NULL;
list_for_each_entry(device, &dma_device_list, global_node) {
if (!dma_has_cap(cap, device->cap_mask) ||
dma_has_cap(DMA_PRIVATE, device->cap_mask))
continue;
list_for_each_entry(chan, &device->channels, device_node) {
if (!chan->client_count)
continue;
if (!min || chan->table_count < min->table_count)
min = chan;
if (dma_chan_is_local(chan, cpu))
if (!localmin ||
chan->table_count < localmin->table_count)
localmin = chan;
}
}
chan = localmin ? localmin : min;
if (chan)
chan->table_count++;
return chan;
}
/**
* dma_channel_rebalance - redistribute the available channels
*
* Optimize for cpu isolation (each cpu gets a dedicated channel for an
* operation type) in the SMP case, and operation isolation (avoid
* multi-tasking channels) in the non-SMP case. Must be called under
* dma_list_mutex.
*/
static void dma_channel_rebalance(void)
{
struct dma_chan *chan;
struct dma_device *device;
int cpu;
int cap;
/* undo the last distribution */
for_each_dma_cap_mask(cap, dma_cap_mask_all)
for_each_possible_cpu(cpu)
per_cpu_ptr(channel_table[cap], cpu)->chan = NULL;
list_for_each_entry(device, &dma_device_list, global_node) {
if (dma_has_cap(DMA_PRIVATE, device->cap_mask))
continue;
list_for_each_entry(chan, &device->channels, device_node)
chan->table_count = 0;
}
/* don't populate the channel_table if no clients are available */
if (!dmaengine_ref_count)
return;
/* redistribute available channels */
for_each_dma_cap_mask(cap, dma_cap_mask_all)
for_each_online_cpu(cpu) {
chan = min_chan(cap, cpu);
per_cpu_ptr(channel_table[cap], cpu)->chan = chan;
}
}
#define dma_device_satisfies_mask(device, mask) \ #define dma_device_satisfies_mask(device, mask) \
__dma_device_satisfies_mask((device), &(mask)) __dma_device_satisfies_mask((device), &(mask))
static int static int
@ -289,57 +433,6 @@ enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie)
} }
EXPORT_SYMBOL(dma_sync_wait); EXPORT_SYMBOL(dma_sync_wait);
/**
* dma_cap_mask_all - enable iteration over all operation types
*/
static dma_cap_mask_t dma_cap_mask_all;
/**
* dma_chan_tbl_ent - tracks channel allocations per core/operation
* @chan - associated channel for this entry
*/
struct dma_chan_tbl_ent {
struct dma_chan *chan;
};
/**
* channel_table - percpu lookup table for memory-to-memory offload providers
*/
static struct dma_chan_tbl_ent __percpu *channel_table[DMA_TX_TYPE_END];
static int __init dma_channel_table_init(void)
{
enum dma_transaction_type cap;
int err = 0;
bitmap_fill(dma_cap_mask_all.bits, DMA_TX_TYPE_END);
/* 'interrupt', 'private', and 'slave' are channel capabilities,
* but are not associated with an operation so they do not need
* an entry in the channel_table
*/
clear_bit(DMA_INTERRUPT, dma_cap_mask_all.bits);
clear_bit(DMA_PRIVATE, dma_cap_mask_all.bits);
clear_bit(DMA_SLAVE, dma_cap_mask_all.bits);
for_each_dma_cap_mask(cap, dma_cap_mask_all) {
channel_table[cap] = alloc_percpu(struct dma_chan_tbl_ent);
if (!channel_table[cap]) {
err = -ENOMEM;
break;
}
}
if (err) {
pr_err("initialization failure\n");
for_each_dma_cap_mask(cap, dma_cap_mask_all)
free_percpu(channel_table[cap]);
}
return err;
}
arch_initcall(dma_channel_table_init);
/** /**
* dma_find_channel - find a channel to carry out the operation * dma_find_channel - find a channel to carry out the operation
* @tx_type: transaction type * @tx_type: transaction type
@ -370,97 +463,6 @@ void dma_issue_pending_all(void)
} }
EXPORT_SYMBOL(dma_issue_pending_all); EXPORT_SYMBOL(dma_issue_pending_all);
/**
* dma_chan_is_local - returns true if the channel is in the same numa-node as the cpu
*/
static bool dma_chan_is_local(struct dma_chan *chan, int cpu)
{
int node = dev_to_node(chan->device->dev);
return node == NUMA_NO_NODE ||
cpumask_test_cpu(cpu, cpumask_of_node(node));
}
/**
* min_chan - returns the channel with min count and in the same numa-node as the cpu
* @cap: capability to match
* @cpu: cpu index which the channel should be close to
*
* If some channels are close to the given cpu, the one with the lowest
* reference count is returned. Otherwise, cpu is ignored and only the
* reference count is taken into account.
* Must be called under dma_list_mutex.
*/
static struct dma_chan *min_chan(enum dma_transaction_type cap, int cpu)
{
struct dma_device *device;
struct dma_chan *chan;
struct dma_chan *min = NULL;
struct dma_chan *localmin = NULL;
list_for_each_entry(device, &dma_device_list, global_node) {
if (!dma_has_cap(cap, device->cap_mask) ||
dma_has_cap(DMA_PRIVATE, device->cap_mask))
continue;
list_for_each_entry(chan, &device->channels, device_node) {
if (!chan->client_count)
continue;
if (!min || chan->table_count < min->table_count)
min = chan;
if (dma_chan_is_local(chan, cpu))
if (!localmin ||
chan->table_count < localmin->table_count)
localmin = chan;
}
}
chan = localmin ? localmin : min;
if (chan)
chan->table_count++;
return chan;
}
/**
* dma_channel_rebalance - redistribute the available channels
*
* Optimize for cpu isolation (each cpu gets a dedicated channel for an
* operation type) in the SMP case, and operation isolation (avoid
* multi-tasking channels) in the non-SMP case. Must be called under
* dma_list_mutex.
*/
static void dma_channel_rebalance(void)
{
struct dma_chan *chan;
struct dma_device *device;
int cpu;
int cap;
/* undo the last distribution */
for_each_dma_cap_mask(cap, dma_cap_mask_all)
for_each_possible_cpu(cpu)
per_cpu_ptr(channel_table[cap], cpu)->chan = NULL;
list_for_each_entry(device, &dma_device_list, global_node) {
if (dma_has_cap(DMA_PRIVATE, device->cap_mask))
continue;
list_for_each_entry(chan, &device->channels, device_node)
chan->table_count = 0;
}
/* don't populate the channel_table if no clients are available */
if (!dmaengine_ref_count)
return;
/* redistribute available channels */
for_each_dma_cap_mask(cap, dma_cap_mask_all)
for_each_online_cpu(cpu) {
chan = min_chan(cap, cpu);
per_cpu_ptr(channel_table[cap], cpu)->chan = chan;
}
}
int dma_get_slave_caps(struct dma_chan *chan, struct dma_slave_caps *caps) int dma_get_slave_caps(struct dma_chan *chan, struct dma_slave_caps *caps)
{ {
struct dma_device *device; struct dma_device *device;
@ -1376,5 +1378,3 @@ static int __init dma_bus_init(void)
return class_register(&dma_devclass); return class_register(&dma_devclass);
} }
arch_initcall(dma_bus_init); arch_initcall(dma_bus_init);