TWxSoftware/twx-linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

bnxt_en: Modify the NAPI logic for the new P7 chips

Browse Source 
Modify the NAPI logic for the new doorbell mechanism on P7 chips.
These changes are compatible with the current P5 chips.

In the current logic, bnxt_poll_p5() services 1 or more CQs for each
MSIX.  Each MSIX has an associated NQ and each NQ has 1 or more
associated CQs.  If any CQ reaches NAPI budget, we'll stay in polling
mode and will unconditionally check and service all CQs until we exit
polling.  We always re-arm all CQs when we exit polling.

To be compatible with the new Toggle bit mechanism in P7 chips, we need
to modify the logic so that we service and re-arm the CQ only if we
receive an NQE notification for work for that CQ.  We add a new
had_nqe_notify bit to the cp_ring_info structure and it gets set when we
see the NQE notification for that CQ anytime during polling.  We'll
service and re-arm only the CQs with the had_nqe_notify bits set.

Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Link: https://lore.kernel.org/r/20231120234405.194542-13-michael.chan@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Michael Chan
2023-11-20 15:44:04 -08:00
committed by Jakub Kicinski
parent c09d22674b
commit f94471f3ce
2 changed files with 10 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files
drivers/net/ethernet/broadcom/bnxt/bnxt.c
+8 -2
View File
@@ -2854,8 +2854,11 @@ static int __bnxt_poll_cqs(struct bnxt *bp, struct bnxt_napi *bnapi, int budget)
for (i = 0; i < cpr->cp_ring_count; i++) {
struct bnxt_cp_ring_info *cpr2 = &cpr->cp_ring_arr[i];
work_done += __bnxt_poll_work(bp, cpr2, budget - work_done);
cpr->has_more_work |= cpr2->has_more_work;
if (cpr2->had_nqe_notify) {
work_done += __bnxt_poll_work(bp, cpr2,
budget - work_done);
cpr->has_more_work |= cpr2->has_more_work;
}
}
return work_done;
}
@@ -2876,6 +2879,8 @@ static void __bnxt_poll_cqs_done(struct bnxt *bp, struct bnxt_napi *bnapi,
DB_RING_IDX(db, cpr2->cp_raw_cons),
db->doorbell);
cpr2->had_work_done = 0;
if (dbr_type == DBR_TYPE_CQ_ARMALL)
cpr2->had_nqe_notify = 0;
}
}
__bnxt_poll_work_done(bp, bnapi, budget);
@@ -2934,6 +2939,7 @@ static int bnxt_poll_p5(struct napi_struct *napi, int budget)
idx = BNXT_NQ_HDL_IDX(idx);
cpr2 = &cpr->cp_ring_arr[idx];
cpr2->had_nqe_notify = 1;
work_done += __bnxt_poll_work(bp, cpr2,
budget - work_done);
cpr->has_more_work |= cpr2->has_more_work;
drivers/net/ethernet/broadcom/bnxt/bnxt.h
+2
View File
@@ -1017,6 +1017,8 @@ struct bnxt_cp_ring_info {
u8 had_work_done:1;
u8 has_more_work:1;
u8 had_nqe_notify:1;
u8 cp_ring_type;
u8 cp_idx;