diff options
author | Julian Wiedmann <jwi@linux.ibm.com> | 2020-03-11 18:07:11 +0100 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2020-03-11 23:52:31 -0700 |
commit | 5d4f78564c9ca38146102c4f8998edcad5afbc22 (patch) | |
tree | 74c8dbd77cc1afe6f0464a568c19d35ef7588029 /drivers/s390/net/qeth_core.h | |
parent | 0f75e149298bedc48db03259a38a303611d247b1 (diff) |
s390/qeth: implement smarter resizing of the RX buffer pool
The RX buffer pool is allocated in qeth_alloc_qdio_queues().
A subsequent pool resizing is then handled in a very simple way:
first free the current pool, then allocate a new pool of the requested
size.
There's two ways where this can go wrong:
1. if the resize action happens _before_ the initial pool was allocated,
then a subsequent initialization will call qeth_alloc_qdio_queues()
and fill the pool with a second(!) set of pages. We consume twice the
planned amount of memory.
This is easy to fix - just skip the resizing if the queues haven't
been allocated yet.
2. if the initial pool was created by qeth_alloc_qdio_queues() but a
subsequent resizing fails, then the device has no(!) RX buffer pool.
The next initialization will _not_ call qeth_alloc_qdio_queues(), and
attempting to back the RX buffers with pages in
qeth_init_qdio_queues() will fail.
Not very difficult to fix either - instead of re-allocating the whole
pool, just allocate/free as many entries to match the desired size.
Fixes: 4a71df50047f ("qeth: new qeth device driver")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/s390/net/qeth_core.h')
-rw-r--r-- | drivers/s390/net/qeth_core.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h index 242b05f644eb..468cada49e72 100644 --- a/drivers/s390/net/qeth_core.h +++ b/drivers/s390/net/qeth_core.h @@ -983,7 +983,7 @@ extern const struct attribute_group qeth_device_blkt_group; extern const struct device_type qeth_generic_devtype; const char *qeth_get_cardname_short(struct qeth_card *); -int qeth_realloc_buffer_pool(struct qeth_card *, int); +int qeth_resize_buffer_pool(struct qeth_card *card, unsigned int count); int qeth_core_load_discipline(struct qeth_card *, enum qeth_discipline_id); void qeth_core_free_discipline(struct qeth_card *); |