renegade-project/linux-next
2
0
Fork 0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-29 15:43:59 +08:00
Code

net: mvpp2: add comments about smp_processor_id() usage

Browse Source 
A previous commit modified a number of smp_processor_id() used in
migration-enabled contexts into get_cpu/put_cpu sections. However, a few
smp_processor_id() calls remain in the driver, and this commit adds
comments explaining why they can be kept.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Thomas Petazzoni 2017-06-22 14:23:18 +02:00 committed by David S. Miller
parent 0c461e050c
commit e0af22d9fd
1 changed files with 29 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

33
drivers/net/ethernet/marvell/mvpp2.c
View File

@ -4162,7 +4162,10 @@ static inline void mvpp2_interrupts_disable(struct mvpp2_port *port)
MVPP2_ISR_DISABLE_INTERRUPT(cpu_mask));
}
/* Mask the current CPU's Rx/Tx interrupts */
/* Mask the current CPU's Rx/Tx interrupts
* Called by on_each_cpu(), guaranteed to run with migration disabled,
* using smp_processor_id() is OK.
*/
static void mvpp2_interrupts_mask(void *arg)
{
struct mvpp2_port *port = arg;
@ -4171,7 +4174,10 @@ static void mvpp2_interrupts_mask(void *arg)
MVPP2_ISR_RX_TX_MASK_REG(port->id), 0);
}
/* Unmask the current CPU's Rx/Tx interrupts */
/* Unmask the current CPU's Rx/Tx interrupts.
* Called by on_each_cpu(), guaranteed to run with migration disabled,
* using smp_processor_id() is OK.
*/
static void mvpp2_interrupts_unmask(void *arg)
{
struct mvpp2_port *port = arg;
@ -4554,7 +4560,11 @@ mvpp2_txq_next_desc_get(struct mvpp2_tx_queue *txq)
return txq->descs + tx_desc;
}
/* Update HW with number of aggregated Tx descriptors to be sent */
/* Update HW with number of aggregated Tx descriptors to be sent
*
* Called only from mvpp2_tx(), so migration is disabled, using
* smp_processor_id() is OK.
*/
static void mvpp2_aggr_txq_pend_desc_add(struct mvpp2_port *port, int pending)
{
/* aggregated access - relevant TXQ number is written in TX desc */
@ -4565,6 +4575,9 @@ static void mvpp2_aggr_txq_pend_desc_add(struct mvpp2_port *port, int pending)
/* Check if there are enough free descriptors in aggregated txq.
* If not, update the number of occupied descriptors and repeat the check.
*
* Called only from mvpp2_tx(), so migration is disabled, using
* smp_processor_id() is OK.
*/
static int mvpp2_aggr_desc_num_check(struct mvpp2 *priv,
struct mvpp2_tx_queue *aggr_txq, int num)
@ -4583,7 +4596,12 @@ static int mvpp2_aggr_desc_num_check(struct mvpp2 *priv,
return 0;
}
/* Reserved Tx descriptors allocation request */
/* Reserved Tx descriptors allocation request
*
* Called only from mvpp2_txq_reserved_desc_num_proc(), itself called
* only by mvpp2_tx(), so migration is disabled, using
* smp_processor_id() is OK.
*/
static int mvpp2_txq_alloc_reserved_desc(struct mvpp2 *priv,
struct mvpp2_tx_queue *txq, int num)
{
@ -4687,6 +4705,10 @@ static u32 mvpp2_txq_desc_csum(int l3_offs, int l3_proto,
/* Get number of sent descriptors and decrement counter.
* The number of sent descriptors is returned.
* Per-CPU access
*
* Called only from mvpp2_txq_done(), called from mvpp2_tx()
* (migration disabled) and from the TX completion tasklet (migration
* disabled) so using smp_processor_id() is OK.
*/
static inline int mvpp2_txq_sent_desc_proc(struct mvpp2_port *port,
struct mvpp2_tx_queue *txq)
@ -4701,6 +4723,9 @@ static inline int mvpp2_txq_sent_desc_proc(struct mvpp2_port *port,
MVPP2_TRANSMITTED_COUNT_OFFSET;
}
/* Called through on_each_cpu(), so runs on all CPUs, with migration
* disabled, therefore using smp_processor_id() is OK.
*/
static void mvpp2_txq_sent_counter_clear(void *arg)
{
struct mvpp2_port *port = arg;