Re: [PATCH 29/34] net: smc: fix opencoded find_and_set_bit() in smc_wr_tx_get_free_slot_index()
From: Alexandra Winter <wintera@linux.ibm.com>
Date: 2023-11-20 08:44:40
Also in:
linux-s390, lkml
On 18.11.23 16:51, Yury Norov wrote:
quoted hunk ↗ jump to hunk
The function opencodes find_and_set_bit() with a for_each() loop. Fix it, and make the whole function a simple almost one-liner. Signed-off-by: Yury Norov <yury.norov@gmail.com> --- net/smc/smc_wr.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-)diff --git a/net/smc/smc_wr.c b/net/smc/smc_wr.c index 0021065a600a..b6f0cfc52788 100644 --- a/net/smc/smc_wr.c +++ b/net/smc/smc_wr.c@@ -170,15 +170,11 @@ void smc_wr_tx_cq_handler(struct ib_cq *ib_cq, void *cq_context) static inline int smc_wr_tx_get_free_slot_index(struct smc_link *link, u32 *idx) { - *idx = link->wr_tx_cnt; if (!smc_link_sendable(link)) return -ENOLINK; - for_each_clear_bit(*idx, link->wr_tx_mask, link->wr_tx_cnt) { - if (!test_and_set_bit(*idx, link->wr_tx_mask)) - return 0; - } - *idx = link->wr_tx_cnt; - return -EBUSY; + + *idx = find_and_set_bit(link->wr_tx_mask, link->wr_tx_cnt); + return *idx < link->wr_tx_cnt ? 0 : -EBUSY; } /**
My understanding is that you can omit the lines with
- *idx = link->wr_tx_cnt;
because they only apply to the error paths and you checked that the calling function does not use the idx variable in the error cases. Do I understand this correct? If so the removal of these 2 lines is not related to your change of using find_and_set_bit(), do I understand that correctly? If so, it may be worth mentioning that in the commit message.