From: Joe Perches <joe@perches.com>
To: "wanghai (M)" <wanghai38@huawei.com>,
dchickles@marvell.com, sburla@marvell.com, fmanlunas@marvell.com,
davem@davemloft.net, kuba@kernel.org
Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next] liquidio: Remove unneeded cast from memory allocation
Date: Tue, 28 Jul 2020 02:11:26 -0700 [thread overview]
Message-ID: <bffcc7d513e186734d224bda6afdd55033b451de.camel@perches.com> (raw)
In-Reply-To: <ac99bed4-dabc-a003-374f-206753f937cb@huawei.com>
On Tue, 2020-07-28 at 16:42 +0800, wanghai (M) wrote:
> 在 2020/7/25 5:29, Joe Perches 写道:
> > On Fri, 2020-07-24 at 21:00 +0800, Wang Hai wrote:
> > > Remove casting the values returned by memory allocation function.
> > >
> > > Coccinelle emits WARNING:
> > >
> > > ./drivers/net/ethernet/cavium/liquidio/octeon_device.c:1155:14-36: WARNING:
> > > casting value returned by memory allocation function to (struct octeon_dispatch *) is useless.
> > []
> > > diff --git a/drivers/net/ethernet/cavium/liquidio/octeon_device.c b/drivers/net/ethernet/cavium/liquidio/octeon_device.c
> > []
> > > @@ -1152,8 +1152,7 @@ octeon_register_dispatch_fn(struct octeon_device *oct,
> > >
> > > dev_dbg(&oct->pci_dev->dev,
> > > "Adding opcode to dispatch list linked list\n");
> > > - dispatch = (struct octeon_dispatch *)
> > > - vmalloc(sizeof(struct octeon_dispatch));
> > > + dispatch = vmalloc(sizeof(struct octeon_dispatch));
> > More the question is why this is vmalloc at all
> > as the structure size is very small.
> >
> > Likely this should just be kmalloc.
> >
> >
> Thanks for your advice. It is indeed best to use kmalloc here.
> > > if (!dispatch) {
> > > dev_err(&oct->pci_dev->dev,
> > > "No memory to add dispatch function\n");
> > And this dev_err is unnecessary.
> >
> >
> I don't understand why dev_err is not needed here. We can easily know
> that an error has occurred here through dev_err
Memory allocation failures without __GFP_NOWARN. already
do a dump_stack to show the location of the code that
could not successfully allocate memory.
next prev parent reply other threads:[~2020-07-28 9:11 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-24 13:00 [PATCH net-next] liquidio: Remove unneeded cast from memory allocation Wang Hai
2020-07-24 21:29 ` Joe Perches
2020-07-28 8:42 ` wanghai (M)
2020-07-28 9:11 ` Joe Perches [this message]
2020-07-28 13:38 ` wanghai (M)
2020-07-28 15:54 ` Joe Perches
2020-07-30 6:19 ` wanghai (M)
2020-07-28 15:39 Derek Chickles
2020-07-28 15:56 ` Joe Perches
2020-07-28 16:32 Derek Chickles
2020-09-01 14:11 YueHaibing
2020-09-01 18:49 ` David Miller
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