svn commit: r234352 - in head/sys: amd64/linux32 compat/linux i386/linux kern

[Giovanni Trematerra]

2012/4/18 Konstantin Belousov <kostikbel at gmail.com>:
> On Wed, Apr 18, 2012 at 01:52:24PM +0200, Giovanni Trematerra wrote:
>> On Mon, Apr 16, 2012 at 11:22 PM, Jung-uk Kim <jkim at freebsd.org> wrote:
>> > Author: jkim
>> > Date: Mon Apr 16 21:22:02 2012
>> > New Revision: 234352
>> > URL: http://svn.freebsd.org/changeset/base/234352
>> >
>> > Log:
>> >  - Implement pipe2 syscall for Linuxulator.  This syscall appeared in 2.6.27
>> >  but GNU libc used it without checking its kernel version, e. g., Fedora 10.
>> >  - Move pipe(2) implementation for Linuxulator from MD files to MI file,
>> >  sys/compat/linux/linux_file.c.  There is no MD code for this syscall at all.
>> >  - Correct an argument type for pipe() from l_ulong * to l_int *.  Probably
>> >  this was the source of MI/MD confusion.
>> >
>> >  Reviewed by:  emulation
>> >
>> > Modified:
>> >  head/sys/amd64/linux32/linux32_dummy.c
>> >  head/sys/amd64/linux32/linux32_machdep.c
>> >  head/sys/amd64/linux32/syscalls.master
>> >  head/sys/compat/linux/linux_file.c
>> >  head/sys/i386/linux/linux_dummy.c
>> >  head/sys/i386/linux/linux_machdep.c
>> >  head/sys/i386/linux/syscalls.master
>> >  head/sys/kern/sys_pipe.c
>> >
>>
>> I don't think it's worth to change sys/kern/sys_pipe.c just to implement
>> linux_pipe2 in linuxator.
>> You can just revert the changes in sys_pipe.c and call kern_fcntl in linux_pipe2
>> to set appropriate flags for the pipes after you created them with kern_pipe.
>> Please, take a look at this patch
>> http://www.trematerra.net/patches/linux_pipe2.patch
>>
>> It's only test-compiled though.
>> Thank you.
>
> I do think that what Jung-uk did is the right approach, and your suggestion
> is wrong. The way it is done in r234352 serves the purpose of pipe2(2),
> namely, the atomicity of setting O_CLOEXEC and O_NONBLOCK with respect
> to execve(2).

Uhm I'm overlooked that linux threads in linuxolator are actual processes as you
pointed me out in private.

Sorry for the noise.