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Subject[PATCH 3/5] 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>
---
drivers/dma/dmaengine.c | 288 ++++++++++++++++++++--------------------
1 file changed, 144 insertions(+), 144 deletions(-)

diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 776fdf535a3a..1f9a6293f15a 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -164,6 +164,150 @@ static struct class dma_devclass = {

/* --- 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) \
__dma_device_satisfies_mask((device), &(mask))
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);

-/**
- * 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
* @tx_type: transaction type
@@ -370,97 +463,6 @@ void dma_issue_pending_all(void)
}
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)
{
struct dma_device *device;
@@ -1376,5 +1378,3 @@ static int __init dma_bus_init(void)
return class_register(&dma_devclass);
}
arch_initcall(dma_bus_init);
-
-
--
2.20.1
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