From 0b6f499022b6a87d04f56edd2bf863ea76923206 Mon Sep 17 00:00:00 2001 From: Julian Wiedmann Date: Mon, 25 Nov 2019 14:18:29 +0100 Subject: s390/qdio: simplify ACK tracking Current code uses a 'polling' flag to keep track of whether an Input Queue has any ACKed SBALs. QEBSM devices might have multiple ACKed SBALs, and those are tracked separately with 'ack_count'. By also setting ack_count for non-QEBSM devices (to a fixed value of 1), we can use 'ack_count != 0' as replacement for the polling flag. Signed-off-by: Julian Wiedmann Signed-off-by: Vasily Gorbik --- drivers/s390/cio/qdio.h | 4 +--- drivers/s390/cio/qdio_debug.c | 5 ++--- drivers/s390/cio/qdio_main.c | 29 +++++++++++------------------ 3 files changed, 14 insertions(+), 24 deletions(-) (limited to 'drivers/s390/cio') diff --git a/drivers/s390/cio/qdio.h b/drivers/s390/cio/qdio.h index 4b0798472643..ff74eb5fce50 100644 --- a/drivers/s390/cio/qdio.h +++ b/drivers/s390/cio/qdio.h @@ -182,11 +182,9 @@ enum qdio_queue_irq_states { }; struct qdio_input_q { - /* input buffer acknowledgement flag */ - int polling; /* first ACK'ed buffer */ int ack_start; - /* how much sbals are acknowledged with qebsm */ + /* how many SBALs are acknowledged */ int ack_count; /* last time of noticing incoming data */ u64 timestamp; diff --git a/drivers/s390/cio/qdio_debug.c b/drivers/s390/cio/qdio_debug.c index 35410e6eda2e..9c0370b27426 100644 --- a/drivers/s390/cio/qdio_debug.c +++ b/drivers/s390/cio/qdio_debug.c @@ -124,9 +124,8 @@ static int qstat_show(struct seq_file *m, void *v) seq_printf(m, "nr_used: %d ftc: %d\n", atomic_read(&q->nr_buf_used), q->first_to_check); if (q->is_input_q) { - seq_printf(m, "polling: %d ack start: %d ack count: %d\n", - q->u.in.polling, q->u.in.ack_start, - q->u.in.ack_count); + seq_printf(m, "ack start: %d ack count: %d\n", + q->u.in.ack_start, q->u.in.ack_count); seq_printf(m, "DSCI: %x IRQs disabled: %u\n", *(u8 *)q->irq_ptr->dsci, test_bit(QDIO_QUEUE_IRQS_DISABLED, diff --git a/drivers/s390/cio/qdio_main.c b/drivers/s390/cio/qdio_main.c index f8b897b7e78b..3475317c42e5 100644 --- a/drivers/s390/cio/qdio_main.c +++ b/drivers/s390/cio/qdio_main.c @@ -393,19 +393,15 @@ int debug_get_buf_state(struct qdio_q *q, unsigned int bufnr, static inline void qdio_stop_polling(struct qdio_q *q) { - if (!q->u.in.polling) + if (!q->u.in.ack_count) return; - q->u.in.polling = 0; qperf_inc(q, stop_polling); /* show the card that we are not polling anymore */ - if (is_qebsm(q)) { - set_buf_states(q, q->u.in.ack_start, SLSB_P_INPUT_NOT_INIT, - q->u.in.ack_count); - q->u.in.ack_count = 0; - } else - set_buf_state(q, q->u.in.ack_start, SLSB_P_INPUT_NOT_INIT); + set_buf_states(q, q->u.in.ack_start, SLSB_P_INPUT_NOT_INIT, + q->u.in.ack_count); + q->u.in.ack_count = 0; } static inline void account_sbals(struct qdio_q *q, unsigned int count) @@ -451,8 +447,7 @@ static inline void inbound_primed(struct qdio_q *q, unsigned int start, /* for QEBSM the ACK was already set by EQBS */ if (is_qebsm(q)) { - if (!q->u.in.polling) { - q->u.in.polling = 1; + if (!q->u.in.ack_count) { q->u.in.ack_count = count; q->u.in.ack_start = start; return; @@ -471,12 +466,12 @@ static inline void inbound_primed(struct qdio_q *q, unsigned int start, * or by the next inbound run. */ new = add_buf(start, count - 1); - if (q->u.in.polling) { + if (q->u.in.ack_count) { /* reset the previous ACK but first set the new one */ set_buf_state(q, new, SLSB_P_INPUT_ACK); set_buf_state(q, q->u.in.ack_start, SLSB_P_INPUT_NOT_INIT); } else { - q->u.in.polling = 1; + q->u.in.ack_count = 1; set_buf_state(q, new, SLSB_P_INPUT_ACK); } @@ -1479,13 +1474,12 @@ static int handle_inbound(struct qdio_q *q, unsigned int callflags, qperf_inc(q, inbound_call); - if (!q->u.in.polling) + if (!q->u.in.ack_count) goto set; /* protect against stop polling setting an ACK for an emptied slsb */ if (count == QDIO_MAX_BUFFERS_PER_Q) { /* overwriting everything, just delete polling status */ - q->u.in.polling = 0; q->u.in.ack_count = 0; goto set; } else if (buf_in_between(q->u.in.ack_start, bufnr, count)) { @@ -1495,15 +1489,14 @@ static int handle_inbound(struct qdio_q *q, unsigned int callflags, diff = sub_buf(diff, q->u.in.ack_start); q->u.in.ack_count -= diff; if (q->u.in.ack_count <= 0) { - q->u.in.polling = 0; q->u.in.ack_count = 0; goto set; } q->u.in.ack_start = add_buf(q->u.in.ack_start, diff); + } else { + /* the only ACK will be deleted */ + q->u.in.ack_count = 0; } - else - /* the only ACK will be deleted, so stop polling */ - q->u.in.polling = 0; } set: -- cgit v1.2.3