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 ab24a5e8ee8a..556cb816fe5d 100644 --- a/drivers/net/ethernet/marvell/octeontx2/af/rvu.c +++ b/drivers/net/ethernet/marvell/octeontx2/af/rvu.c @@ -88,7 +88,8 @@ 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;
@@ -103,6 +104,15 @@ 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; }