From: Christophe LEROY <christophe.leroy@c-s.fr>
To: "linuxppc-dev@lists.ozlabs.org" <linuxppc-dev@lists.ozlabs.org>
Subject: usercopy in PPC64
Date: Tue, 30 May 2017 14:36:39 +0200 [thread overview]
Message-ID: <d25be832-2030-4bc8-dbc5-4baebb759279@c-s.fr> (raw)
Hi all powerpc64 experts,
While looking at the usercopy efficiency for PPC32, I noticed something
which looks strange.
In asm/uaccess.h, raw_copy_from_user() and raw_copy_to_user() implements
a fast path using get_user() and put_user() for copies of constant size < 8.
But INLINE_COPY_FROM_USER and INLINE_COPY_TO_USER are only defined for
PPC32, so PPC64 will call __copy_tofrom_user() even for small constant
size copies. Is that wanted ?
Regards
Christophe
next reply other threads:[~2017-05-30 12:36 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-05-30 12:36 Christophe LEROY [this message]
2017-05-31 6:55 ` usercopy in PPC64 Christophe LEROY
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