timerfd incompatibility on mips

[Bernhard Reutner-Fischer]

"Alexander Gordeev" <lasaine at lvk.cs.msu.su> wrote:

>В Thu, 27 Jan 2011 16:53:39 -0800 (PST)
>Davide Libenzi <davidel at xmailserver.org> пишет:
>
>> On Fri, 28 Jan 2011, Alexander Gordeev wrote:
>> 
>> > Hi!
>> > 
>> > I've just found a problem with TFD_NONBLOCK flag that can be passed
>to
>> > timerfd_create.
>> > 
>> > <uclibc>/libc/sysdeps/linux/common/sys/timerfd.h which is installed
>> > to /usr/include/sys/timerfd.h defines TFD_NONBLOCK as 04000 ie
>0x800.
>> > BTW glibc/eglibc headers do the same thing.
>> > 
>> > <linux>/include/linux/timerfd.h declares it as O_NONBLOCK which is
>> > defined in fcntl.h. Usually O_NONBLOCK is 0x800 too but some
>> > architectures including MIPS it redefine it:
>> > 
>> > arch/mips/include/asm/fcntl.h:#define O_NONBLOCK	0x0080
>> > arch/alpha/include/asm/fcntl.h:#define O_NONBLOCK	00004
>> > arch/sparc/include/asm/fcntl.h:#define O_NONBLOCK	0x4000
>> > arch/parisc/include/asm/fcntl.h:#define O_NONBLOCK	000200004
>> > 
>> > My tests show that kernel thinks that TFD_NONBLOCK is 0x80 on MIPS.
>I
>> > get what I want when I pass 0x80 and EINVAL when I pass 0x800. I
>don't
>> > know why there are such uncertain things in Linux. Probably the
>problem
>> > should be fixed in the kernel.
>> > 
>> > Right now one cannot use timerfd_create(..., TFD_NONBLOCK) on MIPS
>but
>> > can use timerfd_create(..., O_NONBLOCK) instead.
>> 
>> Ther kernel definition (include/linux/timerfd.h) maps it directly to 
>> O_NONBLOCK, but I am noticing that glibc bolt in the value.
>> I don't think this is a kernel fix.
>
>Yes, but linux/timerfd.h is not installed so timerfd.h from *libc
>cannot include it. So adding it to include/linux/Kbuild would be a
>first step to make them not hard-code the value. Right?
>
>-- 
>  Alexander
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Hi,

Sounds we need a mips specific timerfd.h then.
Can you send a tested patch against current master, please?