On 2020/9/18 22:25, Jason Gunthorpe wrote:
> On Wed, Sep 09, 2020 at 05:09:23PM +0800, Weihang Li wrote:
>> From: Yangyang Li <liyangyang20@xxxxxxxxxx>
>>
>> In order to improve performance by balancing the load between different
>> banks of cache, the QPC cache is desigend to choose one of 8 banks
>> according to lower 3 bits of QPN, and the CQC cache uses the lower 2 bits
>> to choose one from 4 banks. The hns driver needs to count the number of
>> QP/CQ on each bank and then assigns the QP/CQ being created to the bank
>> with the minimum load first.
>>
>> Signed-off-by: Yangyang Li <liyangyang20@xxxxxxxxxx>
>> Signed-off-by: Weihang Li <liweihang@xxxxxxxxxx>
>> drivers/infiniband/hw/hns/hns_roce_alloc.c | 46 +++++++++++++++++++++++++++++
>> drivers/infiniband/hw/hns/hns_roce_cq.c | 38 +++++++++++++++++++++++-
>> drivers/infiniband/hw/hns/hns_roce_device.h | 8 +++++
>> drivers/infiniband/hw/hns/hns_roce_qp.c | 39 ++++++++++++++++++++++--
>> 4 files changed, 128 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/infiniband/hw/hns/hns_roce_alloc.c b/drivers/infiniband/hw/hns/hns_roce_alloc.c
>> index a522cb2..cbe955c 100644
>> +++ b/drivers/infiniband/hw/hns/hns_roce_alloc.c
>> @@ -36,6 +36,52 @@
>> #include "hns_roce_device.h"
>> #include <rdma/ib_umem.h>
>>
>> +static int get_bit(struct hns_roce_bitmap *bitmap, u8 bankid,
>> + u8 mod, unsigned long *obj)
>> +{
>> + unsigned long offset_bak = bitmap->last;
>> + bool one_circle_flag = false;
>> +
>> + do {
>> + *obj = find_next_zero_bit(bitmap->table, bitmap->max,
>> + bitmap->last);
>> + if (*obj >= bitmap->max) {
>> + *obj = find_first_zero_bit(bitmap->table, bitmap->max);
>> + one_circle_flag = true;
>> + }
>> +
>> + bitmap->last = (*obj + 1);
>> + if (bitmap->last == bitmap->max) {
>> + bitmap->last = 0;
>> + one_circle_flag = true;
>> + }
>> +
>> + /* Not found after a round of search */
>> + if (bitmap->last >= offset_bak && one_circle_flag)
>> + return -EINVAL;
>> +
>> + } while (*obj % mod != bankid);
>> +
>> + return 0;
>> +}
>
> This looks like an ida, is there a reason it has to be open coded?
>
> Jason
>
Hi Jason,
Do you mean that the function get_bit() may be replaced by the ida
interfaces?
Thanks for your reminder, we didn't notice these interfaces before.
We'll look at them to see if they can meet our needs. If not, we will
explain in more detail about why we implement this function.
Weihang
