[S390] qdio: improve inbound buffer acknowledgement
- Use automatic acknowledgement of incoming buffers in QEBSM mode
- Move ACK for non-QEBSM mode always to the newest buffer to prevent
a race with qdio_stop_polling
- Remove the polling spinlock, the upper layer drivers return new buffers
in the same code path and could not run in parallel
- Don't flood the error log in case of no-target-buffer-empty
- In handle_inbound we check if we would overwrite an ACK'ed buffer, if so
advance the pointer to the oldest ACK'ed buffer so we don't overwrite an
empty buffer in qdio_stop_polling
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/cio/qdio.h b/drivers/s390/cio/qdio.h
index 7b50882..c60f256 100644
--- a/drivers/s390/cio/qdio.h
+++ b/drivers/s390/cio/qdio.h
@@ -112,12 +112,12 @@
}
static inline int do_eqbs(u64 token, unsigned char *state, int queue,
- int *start, int *count)
+ int *start, int *count, int ack)
{
register unsigned long _ccq asm ("0") = *count;
register unsigned long _token asm ("1") = token;
unsigned long _queuestart = ((unsigned long)queue << 32) | *start;
- unsigned long _state = 0;
+ unsigned long _state = (unsigned long)ack << 63;
asm volatile(
" .insn rrf,0xB99c0000,%1,%2,0,0"
@@ -134,7 +134,7 @@
static inline int do_sqbs(u64 token, unsigned char state, int queue,
int *start, int *count) { return 0; }
static inline int do_eqbs(u64 token, unsigned char *state, int queue,
- int *start, int *count) { return 0; }
+ int *start, int *count, int ack) { return 0; }
#endif /* CONFIG_64BIT */
struct qdio_irq;
@@ -187,11 +187,11 @@
/* input buffer acknowledgement flag */
int polling;
+ /* how much sbals are acknowledged with qebsm */
+ int ack_count;
+
/* last time of noticing incoming data */
u64 timestamp;
-
- /* lock for clearing the acknowledgement */
- spinlock_t lock;
};
struct qdio_output_q {
@@ -351,10 +351,13 @@
((bufnr + 1) & QDIO_MAX_BUFFERS_MASK)
#define add_buf(bufnr, inc) \
((bufnr + inc) & QDIO_MAX_BUFFERS_MASK)
+#define sub_buf(bufnr, dec) \
+ ((bufnr - dec) & QDIO_MAX_BUFFERS_MASK)
/* prototypes for thin interrupt */
void qdio_sync_after_thinint(struct qdio_q *q);
-int get_buf_state(struct qdio_q *q, unsigned int bufnr, unsigned char *state);
+int get_buf_state(struct qdio_q *q, unsigned int bufnr, unsigned char *state,
+ int auto_ack);
void qdio_check_outbound_after_thinint(struct qdio_q *q);
int qdio_inbound_q_moved(struct qdio_q *q);
void qdio_kick_inbound_handler(struct qdio_q *q);
@@ -388,6 +391,8 @@
void qdio_print_subchannel_info(struct qdio_irq *irq_ptr,
struct ccw_device *cdev);
void qdio_release_memory(struct qdio_irq *irq_ptr);
+int qdio_setup_create_sysfs(struct ccw_device *cdev);
+void qdio_setup_destroy_sysfs(struct ccw_device *cdev);
int qdio_setup_init(void);
void qdio_setup_exit(void);
