| Message ID | 20190628025055.16242-1-huangfq.daxian@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | None | expand |
Le 28/06/2019 à 04:50, Fuqian Huang a écrit : > In commit af7ddd8a627c > ("Merge tag 'dma-mapping-4.21' of git://git.infradead.org/users/hch/dma-mapping"), > dma_alloc_coherent has already zeroed the memory. > So memset is not needed. You are refering to a merge commit, is that correct ? I can't see anything related in that commit, can you please pinpoint it ? As far as I can see, on powerpc the memory has always been zeroized (since 2005 at least). Christophe > > Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com> > --- > sound/ppc/pmac.c | 1 - > 1 file changed, 1 deletion(-) > > diff --git a/sound/ppc/pmac.c b/sound/ppc/pmac.c > index 1b11e53f6a62..1ab12f4f8631 100644 > --- a/sound/ppc/pmac.c > +++ b/sound/ppc/pmac.c > @@ -56,7 +56,6 @@ static int snd_pmac_dbdma_alloc(struct snd_pmac *chip, struct pmac_dbdma *rec, i > if (rec->space == NULL) > return -ENOMEM; > rec->size = size; > - memset(rec->space, 0, rsize); > rec->cmds = (void __iomem *)DBDMA_ALIGN(rec->space); > rec->addr = rec->dma_base + (unsigned long)((char *)rec->cmds - (char *)rec->space); > >
The merge commit log tells (dma-mapping: zero memory returned from
dma_alloc_* and deprecating the dma_zalloc_coherent).
I used this commit just want to say that dma_alloc_coherent has
zeroed the allocated memory.
Sorry for this mistake.
Maybe this commit 518a2f1925c3("dma-mapping: zero memory returned from
dma_alloc_*") is correct.
Christophe Leroy <christophe.leroy@c-s.fr> 於 2019年6月28日週五 下午4:59寫道：
>
>
>
> Le 28/06/2019 à 04:50, Fuqian Huang a écrit :
> > In commit af7ddd8a627c
> > ("Merge tag 'dma-mapping-4.21' of git://git.infradead.org/users/hch/dma-mapping"),
> > dma_alloc_coherent has already zeroed the memory.
> > So memset is not needed.
>
> You are refering to a merge commit, is that correct ?
>
> I can't see anything related in that commit, can you please pinpoint it ?
>
> As far as I can see, on powerpc the memory has always been zeroized
> (since 2005 at least).
>
> Christophe
>
> >
> > Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com>
> > ---
> > sound/ppc/pmac.c | 1 -
> > 1 file changed, 1 deletion(-)
> >
> > diff --git a/sound/ppc/pmac.c b/sound/ppc/pmac.c
> > index 1b11e53f6a62..1ab12f4f8631 100644
> > --- a/sound/ppc/pmac.c
> > +++ b/sound/ppc/pmac.c
> > @@ -56,7 +56,6 @@ static int snd_pmac_dbdma_alloc(struct snd_pmac *chip, struct pmac_dbdma *rec, i
> > if (rec->space == NULL)
> > return -ENOMEM;
> > rec->size = size;
> > - memset(rec->space, 0, rsize);
> > rec->cmds = (void __iomem *)DBDMA_ALIGN(rec->space);
> > rec->addr = rec->dma_base + (unsigned long)((char *)rec->cmds - (char *)rec->space);
> >
> >
On Fri, 28 Jun 2019 11:11:08 +0200, Fuqian Huang wrote: > > The merge commit log tells (dma-mapping: zero memory returned from > dma_alloc_* and deprecating the dma_zalloc_coherent). > I used this commit just want to say that dma_alloc_coherent has > zeroed the allocated memory. > Sorry for this mistake. > > Maybe this commit 518a2f1925c3("dma-mapping: zero memory returned from > dma_alloc_*") is correct. Are you going to resubmit v3 patchset? If the correction is specific to this patch, I can correct the description in my side, too... thanks, Takashi > > Christophe Leroy <christophe.leroy@c-s.fr> 於 2019年6月28日週五 下午4:59寫道： > > > > > > > > > Le 28/06/2019 à 04:50, Fuqian Huang a écrit : > > > In commit af7ddd8a627c > > > ("Merge tag 'dma-mapping-4.21' of git://git.infradead.org/users/hch/dma-mapping"), > > > dma_alloc_coherent has already zeroed the memory. > > > So memset is not needed. > > > > You are refering to a merge commit, is that correct ? > > > > I can't see anything related in that commit, can you please pinpoint it ? > > > > As far as I can see, on powerpc the memory has always been zeroized > > (since 2005 at least). > > > > Christophe > > > > > > > > Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com> > > > --- > > > sound/ppc/pmac.c | 1 - > > > 1 file changed, 1 deletion(-) > > > > > > diff --git a/sound/ppc/pmac.c b/sound/ppc/pmac.c > > > index 1b11e53f6a62..1ab12f4f8631 100644 > > > --- a/sound/ppc/pmac.c > > > +++ b/sound/ppc/pmac.c > > > @@ -56,7 +56,6 @@ static int snd_pmac_dbdma_alloc(struct snd_pmac *chip, struct pmac_dbdma *rec, i > > > if (rec->space == NULL) > > > return -ENOMEM; > > > rec->size = size; > > > - memset(rec->space, 0, rsize); > > > rec->cmds = (void __iomem *)DBDMA_ALIGN(rec->space); > > > rec->addr = rec->dma_base + (unsigned long)((char *)rec->cmds - (char *)rec->space); > > > > > > > _______________________________________________ > Alsa-devel mailing list > Alsa-devel@alsa-project.org > https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
Le 28/06/2019 à 11:11, Fuqian Huang a écrit : > The merge commit log tells (dma-mapping: zero memory returned from > dma_alloc_* and deprecating the dma_zalloc_coherent). > I used this commit just want to say that dma_alloc_coherent has > zeroed the allocated memory. > Sorry for this mistake. > > Maybe this commit 518a2f1925c3("dma-mapping: zero memory returned from > dma_alloc_*") is correct. Yes that looks appropriate. And it confirms it was already done on powerpc, as that patch doesn't include any change in powerpc arch. Christophe > > Christophe Leroy <christophe.leroy@c-s.fr> 於 2019年6月28日週五 下午4:59寫道： > >> >> >> >> Le 28/06/2019 à 04:50, Fuqian Huang a écrit : >>> In commit af7ddd8a627c >>> ("Merge tag 'dma-mapping-4.21' of git://git.infradead.org/users/hch/dma-mapping"), >>> dma_alloc_coherent has already zeroed the memory. >>> So memset is not needed. >> >> You are refering to a merge commit, is that correct ? >> >> I can't see anything related in that commit, can you please pinpoint it ? >> >> As far as I can see, on powerpc the memory has always been zeroized >> (since 2005 at least). >> >> Christophe >> >>> >>> Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com> >>> --- >>> sound/ppc/pmac.c | 1 - >>> 1 file changed, 1 deletion(-) >>> >>> diff --git a/sound/ppc/pmac.c b/sound/ppc/pmac.c >>> index 1b11e53f6a62..1ab12f4f8631 100644 >>> --- a/sound/ppc/pmac.c >>> +++ b/sound/ppc/pmac.c >>> @@ -56,7 +56,6 @@ static int snd_pmac_dbdma_alloc(struct snd_pmac *chip, struct pmac_dbdma *rec, i >>> if (rec->space == NULL) >>> return -ENOMEM; >>> rec->size = size; >>> - memset(rec->space, 0, rsize); >>> rec->cmds = (void __iomem *)DBDMA_ALIGN(rec->space); >>> rec->addr = rec->dma_base + (unsigned long)((char *)rec->cmds - (char *)rec->space); >>> >>>
diff --git a/sound/ppc/pmac.c b/sound/ppc/pmac.c index 1b11e53f6a62..1ab12f4f8631 100644 --- a/sound/ppc/pmac.c +++ b/sound/ppc/pmac.c @@ -56,7 +56,6 @@ static int snd_pmac_dbdma_alloc(struct snd_pmac *chip, struct pmac_dbdma *rec, i if (rec->space == NULL) return -ENOMEM; rec->size = size; - memset(rec->space, 0, rsize); rec->cmds = (void __iomem *)DBDMA_ALIGN(rec->space); rec->addr = rec->dma_base + (unsigned long)((char *)rec->cmds - (char *)rec->space);
In commit af7ddd8a627c ("Merge tag 'dma-mapping-4.21' of git://git.infradead.org/users/hch/dma-mapping"), dma_alloc_coherent has already zeroed the memory. So memset is not needed. Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com> --- sound/ppc/pmac.c | 1 - 1 file changed, 1 deletion(-)