Message ID | 20220304011830.2061591-1-chi.minghao@zte.com.cn (mailing list archive) |
---|---|
State | Changes Requested |
Headers | show |
Series | powerpc/sysdev: Use of_device_get_match_data() | expand |
Context | Check | Description |
---|---|---|
snowpatch_ozlabs/github-powerpc_ppctests | success | Successfully ran 8 jobs. |
snowpatch_ozlabs/github-powerpc_selftests | success | Successfully ran 8 jobs. |
snowpatch_ozlabs/github-powerpc_sparse | success | Successfully ran 4 jobs. |
snowpatch_ozlabs/github-powerpc_kernel_qemu | success | Successfully ran 24 jobs. |
snowpatch_ozlabs/github-powerpc_clang | success | Successfully ran 7 jobs. |
Le 04/03/2022 à 02:18, cgel.zte@gmail.com a écrit : > From: Minghao Chi (CGEL ZTE) <chi.minghao@zte.com.cn> > > Use of_device_get_match_data() to simplify the code. > > Reported-by: Zeal Robot <zealci@zte.com.cn> > Signed-off-by: Minghao Chi (CGEL ZTE) <chi.minghao@zte.com.cn> > --- > arch/powerpc/sysdev/fsl_msi.c | 6 +----- > 1 file changed, 1 insertion(+), 5 deletions(-) > > diff --git a/arch/powerpc/sysdev/fsl_msi.c b/arch/powerpc/sysdev/fsl_msi.c > index b3475ae9f236..9d135bbb30b7 100644 > --- a/arch/powerpc/sysdev/fsl_msi.c > +++ b/arch/powerpc/sysdev/fsl_msi.c > @@ -387,7 +387,6 @@ static int fsl_msi_setup_hwirq(struct fsl_msi *msi, struct platform_device *dev, > static const struct of_device_id fsl_of_msi_ids[]; > static int fsl_of_msi_probe(struct platform_device *dev) > { > - const struct of_device_id *match; > struct fsl_msi *msi; > struct resource res, msiir; > int err, i, j, irq_index, count; > @@ -397,10 +396,7 @@ static int fsl_of_msi_probe(struct platform_device *dev) > u32 offset; > struct pci_controller *phb; > > - match = of_match_device(fsl_of_msi_ids, &dev->dev); > - if (!match) > - return -EINVAL; > - features = match->data; > + features = of_device_get_match_data(&dev->dev); What happens when features is NULL ? > > printk(KERN_DEBUG "Setting up Freescale MSI support\n"); >
On Fri, 04 Mar 2022 13:10:19 +0000, Christophe Leroy <christophe.leroy@csgroup.eu> wrote: > > > > Le 04/03/2022 à 02:18, cgel.zte@gmail.com a écrit : > > From: Minghao Chi (CGEL ZTE) <chi.minghao@zte.com.cn> > > > > Use of_device_get_match_data() to simplify the code. > > > > Reported-by: Zeal Robot <zealci@zte.com.cn> > > Signed-off-by: Minghao Chi (CGEL ZTE) <chi.minghao@zte.com.cn> > > --- > > arch/powerpc/sysdev/fsl_msi.c | 6 +----- > > 1 file changed, 1 insertion(+), 5 deletions(-) > > > > diff --git a/arch/powerpc/sysdev/fsl_msi.c b/arch/powerpc/sysdev/fsl_msi.c > > index b3475ae9f236..9d135bbb30b7 100644 > > --- a/arch/powerpc/sysdev/fsl_msi.c > > +++ b/arch/powerpc/sysdev/fsl_msi.c > > @@ -387,7 +387,6 @@ static int fsl_msi_setup_hwirq(struct fsl_msi *msi, struct platform_device *dev, > > static const struct of_device_id fsl_of_msi_ids[]; > > static int fsl_of_msi_probe(struct platform_device *dev) > > { > > - const struct of_device_id *match; > > struct fsl_msi *msi; > > struct resource res, msiir; > > int err, i, j, irq_index, count; > > @@ -397,10 +396,7 @@ static int fsl_of_msi_probe(struct platform_device *dev) > > u32 offset; > > struct pci_controller *phb; > > > > - match = of_match_device(fsl_of_msi_ids, &dev->dev); > > - if (!match) > > - return -EINVAL; > > - features = match->data; > > + features = of_device_get_match_data(&dev->dev); > > What happens when features is NULL ? I did jump at that one too, but as it turns out, it cannot happen, by construction. All the fsl_of_msi_ids[] entries have a non-NULL .data pointer, and you only enter probe if you match a fsl_of_msi_ids[] entry with the DT. So the current check for a NULL match is not something that can happen short of some other bug somewhere. M.
Le 04/03/2022 à 15:26, Marc Zyngier a écrit : > On Fri, 04 Mar 2022 13:10:19 +0000, > Christophe Leroy <christophe.leroy@csgroup.eu> wrote: >> >> >> >> Le 04/03/2022 à 02:18, cgel.zte@gmail.com a écrit : >>> From: Minghao Chi (CGEL ZTE) <chi.minghao@zte.com.cn> >>> >>> Use of_device_get_match_data() to simplify the code. >>> >>> Reported-by: Zeal Robot <zealci@zte.com.cn> >>> Signed-off-by: Minghao Chi (CGEL ZTE) <chi.minghao@zte.com.cn> >>> --- >>> arch/powerpc/sysdev/fsl_msi.c | 6 +----- >>> 1 file changed, 1 insertion(+), 5 deletions(-) >>> >>> diff --git a/arch/powerpc/sysdev/fsl_msi.c b/arch/powerpc/sysdev/fsl_msi.c >>> index b3475ae9f236..9d135bbb30b7 100644 >>> --- a/arch/powerpc/sysdev/fsl_msi.c >>> +++ b/arch/powerpc/sysdev/fsl_msi.c >>> @@ -387,7 +387,6 @@ static int fsl_msi_setup_hwirq(struct fsl_msi *msi, struct platform_device *dev, >>> static const struct of_device_id fsl_of_msi_ids[]; >>> static int fsl_of_msi_probe(struct platform_device *dev) >>> { >>> - const struct of_device_id *match; >>> struct fsl_msi *msi; >>> struct resource res, msiir; >>> int err, i, j, irq_index, count; >>> @@ -397,10 +396,7 @@ static int fsl_of_msi_probe(struct platform_device *dev) >>> u32 offset; >>> struct pci_controller *phb; >>> >>> - match = of_match_device(fsl_of_msi_ids, &dev->dev); >>> - if (!match) >>> - return -EINVAL; >>> - features = match->data; >>> + features = of_device_get_match_data(&dev->dev); >> >> What happens when features is NULL ? > > I did jump at that one too, but as it turns out, it cannot happen, by > construction. All the fsl_of_msi_ids[] entries have a non-NULL .data > pointer, and you only enter probe if you match a fsl_of_msi_ids[] > entry with the DT. > > So the current check for a NULL match is not something that can happen > short of some other bug somewhere. > Ok. Then it would be good to have a sentence explaining that in the commit message. Christophe
Christophe Leroy <christophe.leroy@csgroup.eu> writes: > Le 04/03/2022 à 15:26, Marc Zyngier a écrit : >> On Fri, 04 Mar 2022 13:10:19 +0000, >> Christophe Leroy <christophe.leroy@csgroup.eu> wrote: >>> Le 04/03/2022 à 02:18, cgel.zte@gmail.com a écrit : >>>> From: Minghao Chi (CGEL ZTE) <chi.minghao@zte.com.cn> >>>> >>>> Use of_device_get_match_data() to simplify the code. >>>> >>>> Reported-by: Zeal Robot <zealci@zte.com.cn> >>>> Signed-off-by: Minghao Chi (CGEL ZTE) <chi.minghao@zte.com.cn> >>>> --- >>>> arch/powerpc/sysdev/fsl_msi.c | 6 +----- >>>> 1 file changed, 1 insertion(+), 5 deletions(-) >>>> >>>> diff --git a/arch/powerpc/sysdev/fsl_msi.c b/arch/powerpc/sysdev/fsl_msi.c >>>> index b3475ae9f236..9d135bbb30b7 100644 >>>> --- a/arch/powerpc/sysdev/fsl_msi.c >>>> +++ b/arch/powerpc/sysdev/fsl_msi.c >>>> @@ -387,7 +387,6 @@ static int fsl_msi_setup_hwirq(struct fsl_msi *msi, struct platform_device *dev, >>>> static const struct of_device_id fsl_of_msi_ids[]; >>>> static int fsl_of_msi_probe(struct platform_device *dev) >>>> { >>>> - const struct of_device_id *match; >>>> struct fsl_msi *msi; >>>> struct resource res, msiir; >>>> int err, i, j, irq_index, count; >>>> @@ -397,10 +396,7 @@ static int fsl_of_msi_probe(struct platform_device *dev) >>>> u32 offset; >>>> struct pci_controller *phb; >>>> >>>> - match = of_match_device(fsl_of_msi_ids, &dev->dev); >>>> - if (!match) >>>> - return -EINVAL; >>>> - features = match->data; >>>> + features = of_device_get_match_data(&dev->dev); >>> >>> What happens when features is NULL ? >> >> I did jump at that one too, but as it turns out, it cannot happen, by >> construction. All the fsl_of_msi_ids[] entries have a non-NULL .data >> pointer, and you only enter probe if you match a fsl_of_msi_ids[] >> entry with the DT. >> >> So the current check for a NULL match is not something that can happen >> short of some other bug somewhere. >> > > Ok. > > Then it would be good to have a sentence explaining that in the commit > message. Yes I agree. Too many of these cleanup patches assume the reviewer is intimately familiar with the details of the new API/helper and don't explain things fully in the change log. The helper is: const void *of_device_get_match_data(const struct device *dev) { const struct of_device_id *match; match = of_match_device(dev->driver->of_match_table, dev); if (!match) return NULL; return match->data; } So as Marc says, if we're in probe then there must be a match. IMHO there should be a check for match->data being NULL. Although the current match table contains a non-NULL data for every element, that could easily change in future (although this driver will probably never be updated). The forward declaration of fsl_of_msi_ids should also be removed, as it will no longer be necessary. cheers
diff --git a/arch/powerpc/sysdev/fsl_msi.c b/arch/powerpc/sysdev/fsl_msi.c index b3475ae9f236..9d135bbb30b7 100644 --- a/arch/powerpc/sysdev/fsl_msi.c +++ b/arch/powerpc/sysdev/fsl_msi.c @@ -387,7 +387,6 @@ static int fsl_msi_setup_hwirq(struct fsl_msi *msi, struct platform_device *dev, static const struct of_device_id fsl_of_msi_ids[]; static int fsl_of_msi_probe(struct platform_device *dev) { - const struct of_device_id *match; struct fsl_msi *msi; struct resource res, msiir; int err, i, j, irq_index, count; @@ -397,10 +396,7 @@ static int fsl_of_msi_probe(struct platform_device *dev) u32 offset; struct pci_controller *phb; - match = of_match_device(fsl_of_msi_ids, &dev->dev); - if (!match) - return -EINVAL; - features = match->data; + features = of_device_get_match_data(&dev->dev); printk(KERN_DEBUG "Setting up Freescale MSI support\n");