From mboxrd@z Thu Jan  1 00:00:00 1970
From: John Williams <john.williams@petalogix.com>
Subject: Re: [PATCH] [V3] net: emaclite: adding MDIO and phy lib support
Date: Wed, 10 Feb 2010 08:30:24 +1000
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	grant.likely@secretlab.ca, jwboyer@linux.vnet.ibm.com,
	Sadanand Mutyala <Sadanand.Mutyala@xilinx.com>
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Hi John,

Sorry If I'm painting bike-sheds here, just one tiny tweak might be in
order to standardise your mutex_unlock exit path:

> +static int xemaclite_mdio_read(struct mii_bus *bus, int phy_id, int =
reg)
> +{
> + =A0 =A0 =A0 struct net_local *lp =3D bus->priv;
> + =A0 =A0 =A0 u32 ctrl_reg;
> + =A0 =A0 =A0 u32 rc;
> +
> + =A0 =A0 =A0 mutex_lock(&lp->mdio_mutex);
> +
> + =A0 =A0 =A0 if (xemaclite_mdio_wait(lp)) {
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 mutex_unlock(&lp->mdio_mutex);
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 return -ETIMEDOUT;
> + =A0 =A0 =A0 }

[snip]


> + =A0 =A0 =A0 if (xemaclite_mdio_wait(lp)) {
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 mutex_unlock(&lp->mdio_mutex);
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 return -ETIMEDOUT;
> + =A0 =A0 =A0 }

[snip]


> + =A0 =A0 =A0 dev_dbg(&lp->ndev->dev,
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 "xemaclite_mdio_read(phy_id=3D%i, reg=3D=
%x) =3D=3D %x\n",
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 phy_id, reg, rc);
> +
> + =A0 =A0 =A0 return rc;

Can this be better expressed like this:

my_func() {
  mutex_lock()
=2E.

  if(some error) {
    rc=3D-ETIMEDOUT;
    goto out_unlock;
  }
  ...

  /* success path */
  rc=3D0;
=2E.
out_unlock:
  mutex_unlock()
  return rc;
}


Is this style still favoured in driver exit paths?

Thanks,

John
--=20
John Williams, PhD, B.Eng, B.IT
PetaLogix - Linux Solutions for a Reconfigurable World
w: www.petalogix.com  p: +61-7-30090663  f: +61-7-30090663