[PATCH net-next 8/9] s390/qeth: shrink TX buffer struct

Julian Wiedmann
2021-06-11T07:34:03Z

Convert the large boolean array into a bitmap, this substantially
reduces the struct's size. While at it also clarify the naming.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
---
drivers/s390/net/qeth_core.h | 2 +-
drivers/s390/net/qeth_core_main.c | 7 +++----
2 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h
index ff1064f871e5..f4d554ea0c93 100644
--- a/drivers/s390/net/qeth_core.h
+++ b/drivers/s390/net/qeth_core.h
@@ -437,7 +437,7 @@ struct qeth_qdio_out_buffer {
unsigned int frames;
unsigned int bytes;
struct sk_buff_head skb_list;
- int is_header[QDIO_MAX_ELEMENTS_PER_BUFFER];
+ DECLARE_BITMAP(from_kmem_cache, QDIO_MAX_ELEMENTS_PER_BUFFER);

struct list_head list_entry;
struct qaob *aob;
diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index 0ad175d54c13..62f88ccbd03f 100644
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -1347,9 +1347,8 @@ static void qeth_clear_output_buffer(struct qeth_qdio_out_q *queue,
for (i = 0; i < queue->max_elements; ++i) {
void *data = phys_to_virt(buf->buffer->element[i].addr);

- if (data && buf->is_header[i])
+ if (__test_and_clear_bit(i, buf->from_kmem_cache) && data)
kmem_cache_free(qeth_core_header_cache, data);
- buf->is_header[i] = 0;
}

qeth_scrub_qdio_buffer(buf->buffer, queue->max_elements);
@@ -1393,7 +1392,7 @@ static void qeth_tx_complete_pending_bufs(struct qeth_card *card,
i++) {
void *data = phys_to_virt(aob->sba[i]);

- if (data && buf->is_header[i])
+ if (test_bit(i, buf->from_kmem_cache) && data)
kmem_cache_free(qeth_core_header_cache,
data);
}
@@ -4053,7 +4052,7 @@ static unsigned int qeth_fill_buffer(struct qeth_qdio_out_buffer *buf,

/* HW header is allocated from cache: */
if ((void *)hdr != skb->data)
- buf->is_header[element] = 1;
+ __set_bit(element, buf->from_kmem_cache);
/* HW header was pushed and is contiguous with linear part: */
else if (length > 0 && !PAGE_ALIGNED(data) &&
(data == (char *)hdr + hd_len))
--
2.25.1