From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko Schocher Date: Wed, 08 Jul 2015 07:10:29 +0200 Subject: [U-Boot] [RFC PATCH 10/12] linux_compat: introduce GFP_DMA flag for kmalloc() In-Reply-To: <1436329782-9179-11-git-send-email-yamada.masahiro@socionext.com> References: <1436329782-9179-1-git-send-email-yamada.masahiro@socionext.com> <1436329782-9179-11-git-send-email-yamada.masahiro@socionext.com> Message-ID: <559CB0C5.4050008@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hello Masahiro, Am 08.07.2015 um 06:29 schrieb Masahiro Yamada: > It does not seem efficient to always return cache-aligned memory. > Return aligned memory only when GFP_DMA flag is given. > > My main motivation for this commit is to refactor device_probe() > and device_free() in the next commit. DM_FLAG_ALLOC_PRIV_DMA > should be handled more easily. > > Signed-off-by: Masahiro Yamada > --- > > include/linux/compat.h | 1 + > lib/linux_compat.c | 5 ++++- > 2 files changed, 5 insertions(+), 1 deletion(-) Hmm... I think there are a lot of places in code, where implicit is supposed, that kmalloc returns aligned memory ... so this patch needs testing (USB, DFU and ethernet coming in my mind) bye, Heiko > > diff --git a/include/linux/compat.h b/include/linux/compat.h > index 64988bf..8b7f8ef 100644 > --- a/include/linux/compat.h > +++ b/include/linux/compat.h > @@ -41,6 +41,7 @@ extern struct p_current *current; > #define GFP_NOFS ((gfp_t) 0) > #define GFP_USER ((gfp_t) 0) > #define __GFP_NOWARN ((gfp_t) 0) > +#define GFP_DMA ((__force gfp_t)0x01u) > #define __GFP_ZERO ((__force gfp_t)0x8000u) /* Return zeroed page on success */ > > void *kmalloc(size_t size, int flags); > diff --git a/lib/linux_compat.c b/lib/linux_compat.c > index a936a7e..6da0cfa 100644 > --- a/lib/linux_compat.c > +++ b/lib/linux_compat.c > @@ -18,7 +18,10 @@ void *kmalloc(size_t size, int flags) > { > void *p; > > - p = memalign(ARCH_DMA_MINALIGN, size); > + if (flags & GFP_DMA) > + p = memalign(ARCH_DMA_MINALIGN, size); > + else > + p = malloc(size); > if (flags & __GFP_ZERO) > memset(p, 0, size); > > -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany