do_div() does a 64-by-32 division. Here the divisor is an
unsigned long which on some platforms is 64 bit wide. So use
div64_ul instead of do_div to avoid a possible truncation.
Eliminate the following coccicheck warning:
./drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c:2742:1-7: WARNING:
do_div() does a 64-by-32 division, please consider using div64_ul
instead.
Reported-by: Abaci Robot <redacted>
Signed-off-by: Yang Li <redacted>
---
drivers/net/ethernet/renesas/ravb_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
@@ -2489,7 +2489,7 @@ static int ravb_set_gti(struct net_device *ndev)return-EINVAL;inc=1000000000ULL<<20;-do_div(inc,rate);+inc=div64_ul(inc,rate);if(inc<GTI_TIV_MIN||inc>GTI_TIV_MAX){dev_err(dev,"gti.tiv increment 0x%llx is outside the range 0x%x - 0x%x\n",
Hello!
Why you didn't Cc me (as a reviewer)?
On 18.11.2021 5:50, Yang Li wrote:
quoted hunk
do_div() does a 64-by-32 division. Here the divisor is an
unsigned long which on some platforms is 64 bit wide. So use
div64_ul instead of do_div to avoid a possible truncation.
Eliminate the following coccicheck warning:
./drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c:2742:1-7: WARNING:
do_div() does a 64-by-32 division, please consider using div64_ul
instead.
Reported-by: Abaci Robot <redacted>
Signed-off-by: Yang Li <redacted>
---
drivers/net/ethernet/renesas/ravb_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
From: David Laight <hidden> Date: 2021-11-18 11:09:10
From: Sergey Shtylyov
Sent: 18 November 2021 09:08
On 18.11.2021 5:50, Yang Li wrote:
quoted
do_div() does a 64-by-32 division. Here the divisor is an
unsigned long which on some platforms is 64 bit wide. So use
div64_ul instead of do_div to avoid a possible truncation.
Eliminate the following coccicheck warning:
./drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c:2742:1-7: WARNING:
do_div() does a 64-by-32 division, please consider using div64_ul
instead.
Reported-by: Abaci Robot <redacted>
Signed-off-by: Yang Li <redacted>
---
drivers/net/ethernet/renesas/ravb_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
@@ -2489,7 +2489,7 @@ static int ravb_set_gti(struct net_device *ndev)return-EINVAL;inc=1000000000ULL<<20;-do_div(inc,rate);+inc=div64_ul(inc,rate);
Why not just:
inc = div64_ul(1000000000ULL << 20, rate);
quoted
if (inc < GTI_TIV_MIN || inc > GTI_TIV_MAX) {
dev_err(dev, "gti.tiv increment 0x%llx is outside the range 0x%x - 0x%x\n",
Even with hardware divide a 64/32 divide is likely to be faster that a 64/64 one.
Maybe the coccicheck warning message should suggest checking the domain
of the divisor and then changing the type??
David
-
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