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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
Vinod Koul
parent
686607106f
commit
11a0fd2b3b
@ -164,6 +164,150 @@ static struct class dma_devclass = {
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/* --- client and device registration --- */
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/**
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* dma_cap_mask_all - enable iteration over all operation types
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*/
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static dma_cap_mask_t dma_cap_mask_all;
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/**
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* dma_chan_tbl_ent - tracks channel allocations per core/operation
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* @chan - associated channel for this entry
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*/
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struct dma_chan_tbl_ent {
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struct dma_chan *chan;
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};
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/**
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* channel_table - percpu lookup table for memory-to-memory offload providers
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*/
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static struct dma_chan_tbl_ent __percpu *channel_table[DMA_TX_TYPE_END];
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static int __init dma_channel_table_init(void)
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{
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enum dma_transaction_type cap;
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int err = 0;
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bitmap_fill(dma_cap_mask_all.bits, DMA_TX_TYPE_END);
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/* 'interrupt', 'private', and 'slave' are channel capabilities,
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* but are not associated with an operation so they do not need
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* an entry in the channel_table
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*/
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clear_bit(DMA_INTERRUPT, dma_cap_mask_all.bits);
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clear_bit(DMA_PRIVATE, dma_cap_mask_all.bits);
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clear_bit(DMA_SLAVE, dma_cap_mask_all.bits);
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for_each_dma_cap_mask(cap, dma_cap_mask_all) {
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channel_table[cap] = alloc_percpu(struct dma_chan_tbl_ent);
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if (!channel_table[cap]) {
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err = -ENOMEM;
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break;
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}
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}
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if (err) {
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pr_err("initialization failure\n");
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for_each_dma_cap_mask(cap, dma_cap_mask_all)
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free_percpu(channel_table[cap]);
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}
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return err;
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}
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arch_initcall(dma_channel_table_init);
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/**
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* dma_chan_is_local - returns true if the channel is in the same numa-node as
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* the cpu
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*/
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static bool dma_chan_is_local(struct dma_chan *chan, int cpu)
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{
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int node = dev_to_node(chan->device->dev);
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return node == NUMA_NO_NODE ||
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cpumask_test_cpu(cpu, cpumask_of_node(node));
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}
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/**
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* min_chan - returns the channel with min count and in the same numa-node as
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* the cpu
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* @cap: capability to match
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* @cpu: cpu index which the channel should be close to
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*
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* If some channels are close to the given cpu, the one with the lowest
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* reference count is returned. Otherwise, cpu is ignored and only the
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* reference count is taken into account.
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* Must be called under dma_list_mutex.
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*/
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static struct dma_chan *min_chan(enum dma_transaction_type cap, int cpu)
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{
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struct dma_device *device;
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struct dma_chan *chan;
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struct dma_chan *min = NULL;
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struct dma_chan *localmin = NULL;
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list_for_each_entry(device, &dma_device_list, global_node) {
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if (!dma_has_cap(cap, device->cap_mask) ||
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dma_has_cap(DMA_PRIVATE, device->cap_mask))
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continue;
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list_for_each_entry(chan, &device->channels, device_node) {
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if (!chan->client_count)
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continue;
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if (!min || chan->table_count < min->table_count)
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min = chan;
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if (dma_chan_is_local(chan, cpu))
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if (!localmin ||
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chan->table_count < localmin->table_count)
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localmin = chan;
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}
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}
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chan = localmin ? localmin : min;
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if (chan)
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chan->table_count++;
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return chan;
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}
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/**
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* dma_channel_rebalance - redistribute the available channels
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*
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* Optimize for cpu isolation (each cpu gets a dedicated channel for an
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* operation type) in the SMP case, and operation isolation (avoid
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* multi-tasking channels) in the non-SMP case. Must be called under
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* dma_list_mutex.
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*/
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static void dma_channel_rebalance(void)
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{
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struct dma_chan *chan;
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struct dma_device *device;
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int cpu;
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int cap;
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/* undo the last distribution */
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for_each_dma_cap_mask(cap, dma_cap_mask_all)
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for_each_possible_cpu(cpu)
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per_cpu_ptr(channel_table[cap], cpu)->chan = NULL;
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list_for_each_entry(device, &dma_device_list, global_node) {
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if (dma_has_cap(DMA_PRIVATE, device->cap_mask))
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continue;
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list_for_each_entry(chan, &device->channels, device_node)
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chan->table_count = 0;
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}
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/* don't populate the channel_table if no clients are available */
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if (!dmaengine_ref_count)
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return;
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/* redistribute available channels */
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for_each_dma_cap_mask(cap, dma_cap_mask_all)
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for_each_online_cpu(cpu) {
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chan = min_chan(cap, cpu);
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per_cpu_ptr(channel_table[cap], cpu)->chan = chan;
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}
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}
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#define dma_device_satisfies_mask(device, mask) \
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__dma_device_satisfies_mask((device), &(mask))
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static int
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@ -289,57 +433,6 @@ enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie)
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}
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EXPORT_SYMBOL(dma_sync_wait);
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/**
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* dma_cap_mask_all - enable iteration over all operation types
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*/
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static dma_cap_mask_t dma_cap_mask_all;
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/**
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* dma_chan_tbl_ent - tracks channel allocations per core/operation
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* @chan - associated channel for this entry
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*/
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struct dma_chan_tbl_ent {
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struct dma_chan *chan;
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};
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/**
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* channel_table - percpu lookup table for memory-to-memory offload providers
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*/
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static struct dma_chan_tbl_ent __percpu *channel_table[DMA_TX_TYPE_END];
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static int __init dma_channel_table_init(void)
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{
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enum dma_transaction_type cap;
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int err = 0;
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bitmap_fill(dma_cap_mask_all.bits, DMA_TX_TYPE_END);
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/* 'interrupt', 'private', and 'slave' are channel capabilities,
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* but are not associated with an operation so they do not need
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* an entry in the channel_table
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*/
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clear_bit(DMA_INTERRUPT, dma_cap_mask_all.bits);
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clear_bit(DMA_PRIVATE, dma_cap_mask_all.bits);
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clear_bit(DMA_SLAVE, dma_cap_mask_all.bits);
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for_each_dma_cap_mask(cap, dma_cap_mask_all) {
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channel_table[cap] = alloc_percpu(struct dma_chan_tbl_ent);
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if (!channel_table[cap]) {
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err = -ENOMEM;
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break;
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}
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}
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if (err) {
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pr_err("initialization failure\n");
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for_each_dma_cap_mask(cap, dma_cap_mask_all)
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free_percpu(channel_table[cap]);
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}
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return err;
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}
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arch_initcall(dma_channel_table_init);
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/**
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* dma_find_channel - find a channel to carry out the operation
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* @tx_type: transaction type
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@ -370,97 +463,6 @@ void dma_issue_pending_all(void)
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}
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EXPORT_SYMBOL(dma_issue_pending_all);
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/**
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* dma_chan_is_local - returns true if the channel is in the same numa-node as the cpu
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*/
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static bool dma_chan_is_local(struct dma_chan *chan, int cpu)
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{
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int node = dev_to_node(chan->device->dev);
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return node == NUMA_NO_NODE ||
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cpumask_test_cpu(cpu, cpumask_of_node(node));
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}
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/**
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* min_chan - returns the channel with min count and in the same numa-node as the cpu
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* @cap: capability to match
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* @cpu: cpu index which the channel should be close to
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*
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* If some channels are close to the given cpu, the one with the lowest
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* reference count is returned. Otherwise, cpu is ignored and only the
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* reference count is taken into account.
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* Must be called under dma_list_mutex.
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*/
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static struct dma_chan *min_chan(enum dma_transaction_type cap, int cpu)
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{
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struct dma_device *device;
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struct dma_chan *chan;
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struct dma_chan *min = NULL;
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struct dma_chan *localmin = NULL;
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list_for_each_entry(device, &dma_device_list, global_node) {
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if (!dma_has_cap(cap, device->cap_mask) ||
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dma_has_cap(DMA_PRIVATE, device->cap_mask))
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continue;
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list_for_each_entry(chan, &device->channels, device_node) {
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if (!chan->client_count)
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continue;
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if (!min || chan->table_count < min->table_count)
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min = chan;
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if (dma_chan_is_local(chan, cpu))
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if (!localmin ||
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chan->table_count < localmin->table_count)
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localmin = chan;
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}
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}
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chan = localmin ? localmin : min;
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if (chan)
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chan->table_count++;
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return chan;
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}
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/**
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* dma_channel_rebalance - redistribute the available channels
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*
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* Optimize for cpu isolation (each cpu gets a dedicated channel for an
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* operation type) in the SMP case, and operation isolation (avoid
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* multi-tasking channels) in the non-SMP case. Must be called under
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* dma_list_mutex.
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*/
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static void dma_channel_rebalance(void)
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{
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struct dma_chan *chan;
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struct dma_device *device;
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int cpu;
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int cap;
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/* undo the last distribution */
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for_each_dma_cap_mask(cap, dma_cap_mask_all)
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for_each_possible_cpu(cpu)
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per_cpu_ptr(channel_table[cap], cpu)->chan = NULL;
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list_for_each_entry(device, &dma_device_list, global_node) {
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if (dma_has_cap(DMA_PRIVATE, device->cap_mask))
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continue;
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list_for_each_entry(chan, &device->channels, device_node)
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chan->table_count = 0;
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}
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/* don't populate the channel_table if no clients are available */
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if (!dmaengine_ref_count)
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return;
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/* redistribute available channels */
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for_each_dma_cap_mask(cap, dma_cap_mask_all)
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for_each_online_cpu(cpu) {
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chan = min_chan(cap, cpu);
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per_cpu_ptr(channel_table[cap], cpu)->chan = chan;
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}
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}
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int dma_get_slave_caps(struct dma_chan *chan, struct dma_slave_caps *caps)
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{
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struct dma_device *device;
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@ -1376,5 +1378,3 @@ static int __init dma_bus_init(void)
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return class_register(&dma_devclass);
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}
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arch_initcall(dma_bus_init);
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