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From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Smadar Fuks <smadarf@marvell.com>,
	Sunil Goutham <sgoutham@marvell.com>,
	"David S . Miller" <davem@davemloft.net>,
	Sasha Levin <sashal@kernel.org>,
	netdev@vger.kernel.org
Subject: [PATCH AUTOSEL 5.10 17/25] octeontx2-af: Add additional register check to rvu_poll_reg()
Date: Sat, 11 Sep 2021 09:13:04 -0400	[thread overview]
Message-ID: <20210911131312.285225-17-sashal@kernel.org> (raw)
In-Reply-To: <20210911131312.285225-1-sashal@kernel.org>

From: Smadar Fuks <smadarf@marvell.com>

[ Upstream commit 21274aa1781941884599a97ab59be7f8f36af98c ]

Check one more time before exiting the API with an error.
Fix API to poll at least twice, in case there are other high priority
tasks and this API doesn't get CPU cycles for multiple jiffies update.

In addition, increase timeout from usecs_to_jiffies(10000) to
usecs_to_jiffies(20000), to prevent the case that for CONFIG_100HZ
timeout will be a single jiffies.
A single jiffies results actual timeout that can be any time between
1usec and 10msec. To solve this, a value of usecs_to_jiffies(20000)
ensures that timeout is 2 jiffies.

Signed-off-by: Smadar Fuks <smadarf@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/marvell/octeontx2/af/rvu.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/marvell/octeontx2/af/rvu.c b/drivers/net/ethernet/marvell/octeontx2/af/rvu.c
index 644d28b0692b..c26652436c53 100644
--- a/drivers/net/ethernet/marvell/octeontx2/af/rvu.c
+++ b/drivers/net/ethernet/marvell/octeontx2/af/rvu.c
@@ -84,7 +84,8 @@ static void rvu_setup_hw_capabilities(struct rvu *rvu)
  */
 int rvu_poll_reg(struct rvu *rvu, u64 block, u64 offset, u64 mask, bool zero)
 {
-	unsigned long timeout = jiffies + usecs_to_jiffies(10000);
+	unsigned long timeout = jiffies + usecs_to_jiffies(20000);
+	bool twice = false;
 	void __iomem *reg;
 	u64 reg_val;
 
@@ -99,6 +100,15 @@ int rvu_poll_reg(struct rvu *rvu, u64 block, u64 offset, u64 mask, bool zero)
 		usleep_range(1, 5);
 		goto again;
 	}
+	/* In scenarios where CPU is scheduled out before checking
+	 * 'time_before' (above) and gets scheduled in such that
+	 * jiffies are beyond timeout value, then check again if HW is
+	 * done with the operation in the meantime.
+	 */
+	if (!twice) {
+		twice = true;
+		goto again;
+	}
 	return -EBUSY;
 }
 
-- 
2.30.2


  parent reply	other threads:[~2021-09-11 13:18 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-09-11 13:12 [PATCH AUTOSEL 5.10 01/25] dt-bindings: mtd: gpmc: Fix the ECC bytes vs. OOB bytes equation Sasha Levin
2021-09-11 13:12 ` [PATCH AUTOSEL 5.10 02/25] mfd: db8500-prcmu: Adjust map to reality Sasha Levin
2021-09-11 13:12 ` [PATCH AUTOSEL 5.10 03/25] PCI: Add ACS quirks for NXP LX2xx0 and LX2xx2 platforms Sasha Levin
2021-09-11 13:12 ` [PATCH AUTOSEL 5.10 04/25] fuse: fix use after free in fuse_read_interrupt() Sasha Levin
2021-09-11 13:12 ` [PATCH AUTOSEL 5.10 05/25] PCI: tegra194: Fix handling BME_CHGED event Sasha Levin
2021-09-11 13:12 ` [PATCH AUTOSEL 5.10 06/25] PCI: tegra194: Fix MSI-X programming Sasha Levin
2021-09-11 13:12 ` [PATCH AUTOSEL 5.10 07/25] PCI: tegra: Fix OF node reference leak Sasha Levin
2021-09-11 13:12 ` [PATCH AUTOSEL 5.10 08/25] mfd: Don't use irq_create_mapping() to resolve a mapping Sasha Levin
2021-09-11 13:12 ` [PATCH AUTOSEL 5.10 09/25] PCI: rcar: Fix runtime PM imbalance in rcar_pcie_ep_probe() Sasha Levin
2021-09-11 13:12 ` [PATCH AUTOSEL 5.10 10/25] tracing/probes: Reject events which have the same name of existing one Sasha Levin
2021-09-11 13:12 ` [PATCH AUTOSEL 5.10 11/25] PCI: cadence: Use bitfield for *quirk_retrain_flag* instead of bool Sasha Levin
2021-09-11 13:12 ` [PATCH AUTOSEL 5.10 12/25] PCI: cadence: Add quirk flag to set minimum delay in LTSSM Detect.Quiet state Sasha Levin
2021-09-11 13:13 ` [PATCH AUTOSEL 5.10 13/25] PCI: j721e: Add PCIe support for J7200 Sasha Levin
2021-09-11 13:13 ` [PATCH AUTOSEL 5.10 14/25] PCI: j721e: Add PCIe support for AM64 Sasha Levin
2021-09-11 13:13 ` [PATCH AUTOSEL 5.10 15/25] PCI: Add ACS quirks for Cavium multi-function devices Sasha Levin
2021-09-11 13:13 ` [PATCH AUTOSEL 5.10 16/25] watchdog: Start watchdog in watchdog_set_last_hw_keepalive only if appropriate Sasha Levin
2021-09-11 13:13 ` Sasha Levin [this message]
2021-09-11 13:13 ` [PATCH AUTOSEL 5.10 18/25] Set fc_nlinfo in nh_create_ipv4, nh_create_ipv6 Sasha Levin
2021-09-11 13:13 ` [PATCH AUTOSEL 5.10 19/25] net: usb: cdc_mbim: avoid altsetting toggling for Telit LN920 Sasha Levin
2021-09-11 13:13 ` [PATCH AUTOSEL 5.10 20/25] block, bfq: honor already-setup queue merges Sasha Levin
2021-09-11 13:13 ` [PATCH AUTOSEL 5.10 21/25] PCI: ibmphp: Fix double unmap of io_mem Sasha Levin
2021-09-11 13:13 ` [PATCH AUTOSEL 5.10 22/25] ethtool: Fix an error code in cxgb2.c Sasha Levin
2021-09-11 13:13 ` [PATCH AUTOSEL 5.10 23/25] NTB: Fix an error code in ntb_msit_probe() Sasha Levin
2021-09-11 13:13 ` [PATCH AUTOSEL 5.10 24/25] NTB: perf: Fix an error code in perf_setup_inbuf() Sasha Levin
2021-09-11 13:13 ` [PATCH AUTOSEL 5.10 25/25] net: phylink: add suspend/resume support Sasha Levin

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