[PATCH 4.19 38/66] cxgb4: avoid collecting SGE_QBASE regs during traffic

From: Greg Kroah-Hartman
Date: Mon Apr 12 2021 - 04:46:36 EST


From: Rahul Lakkireddy <rahul.lakkireddy@xxxxxxxxxxx>

[ Upstream commit 1bfb3dea965ff9f6226fd1709338f227363b6061 ]

Accessing SGE_QBASE_MAP[0-3] and SGE_QBASE_INDEX registers can lead
to SGE missing doorbells under heavy traffic. So, only collect them
when adapter is idle. Also update the regdump range to skip collecting
these registers.

Fixes: 80a95a80d358 ("cxgb4: collect SGE PF/VF queue map")
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@xxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
.../net/ethernet/chelsio/cxgb4/cudbg_lib.c | 23 +++++++++++++++----
drivers/net/ethernet/chelsio/cxgb4/t4_hw.c | 3 ++-
2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cudbg_lib.c b/drivers/net/ethernet/chelsio/cxgb4/cudbg_lib.c
index c91e155c147c..544c88f19f24 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cudbg_lib.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cudbg_lib.c
@@ -1400,11 +1400,25 @@ int cudbg_collect_sge_indirect(struct cudbg_init *pdbg_init,
struct cudbg_buffer temp_buff = { 0 };
struct sge_qbase_reg_field *sge_qbase;
struct ireg_buf *ch_sge_dbg;
+ u8 padap_running = 0;
int i, rc;
+ u32 size;

- rc = cudbg_get_buff(pdbg_init, dbg_buff,
- sizeof(*ch_sge_dbg) * 2 + sizeof(*sge_qbase),
- &temp_buff);
+ /* Accessing SGE_QBASE_MAP[0-3] and SGE_QBASE_INDEX regs can
+ * lead to SGE missing doorbells under heavy traffic. So, only
+ * collect them when adapter is idle.
+ */
+ for_each_port(padap, i) {
+ padap_running = netif_running(padap->port[i]);
+ if (padap_running)
+ break;
+ }
+
+ size = sizeof(*ch_sge_dbg) * 2;
+ if (!padap_running)
+ size += sizeof(*sge_qbase);
+
+ rc = cudbg_get_buff(pdbg_init, dbg_buff, size, &temp_buff);
if (rc)
return rc;

@@ -1426,7 +1440,8 @@ int cudbg_collect_sge_indirect(struct cudbg_init *pdbg_init,
ch_sge_dbg++;
}

- if (CHELSIO_CHIP_VERSION(padap->params.chip) > CHELSIO_T5) {
+ if (CHELSIO_CHIP_VERSION(padap->params.chip) > CHELSIO_T5 &&
+ !padap_running) {
sge_qbase = (struct sge_qbase_reg_field *)ch_sge_dbg;
/* 1 addr reg SGE_QBASE_INDEX and 4 data reg
* SGE_QBASE_MAP[0-3]
diff --git a/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c b/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c
index abc2a66754bd..812f4b743d97 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c
@@ -2093,7 +2093,8 @@ void t4_get_regs(struct adapter *adap, void *buf, size_t buf_size)
0x1190, 0x1194,
0x11a0, 0x11a4,
0x11b0, 0x11b4,
- 0x11fc, 0x1274,
+ 0x11fc, 0x123c,
+ 0x1254, 0x1274,
0x1280, 0x133c,
0x1800, 0x18fc,
0x3000, 0x302c,
--
2.30.2