[PATCH] nptl: Add <thread_pointer.h> for m68k

[Michael Jeanson]

On 2024-10-30 11:07, Arjun Shankar wrote:
> Hi Michael,
> 
>> This will be required by the rseq extensible ABI implementation on all
>> Linux architectures exposing the '__rseq_size' and '__rseq_offset'
>> symbols to set the initial value of the 'cpu_id' field which can be used
>> by applications to test if rseq is available and registered. As long as
>> the symbols are exposed it is valid for an application to perform this
>> test even if rseq is not yet implemented in libc for this architecture.
>>
>> Compile tested with build-many-glibcs.py but I don't have access to any
>> hardware to run the tests.
>>
>> Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
>> ---
>> Cc: Florian Weimer <fweimer@redhat.com>
>> Cc: Andreas Schwab <schwab@linux-m68k.org>
>> Cc: Andreas K. Hüttel <dilfridge@gentoo.org>
> 
> I don't have access to this hardware, but I reviewed this for being
> reasonable and verified that it passes build-many-glibcs for m68k
> (which I tested as well).
> 
> Reviewed-by: Arjun Shankar <arjun@redhat.com>

Any objections from machine maintainers to me pushing this?

> 
>> ---
>>  sysdeps/m68k/nptl/thread_pointer.h | 30 ++++++++++++++++++++++++++++++
>>  1 file changed, 30 insertions(+)
>>  create mode 100644 sysdeps/m68k/nptl/thread_pointer.h
>>
>> diff --git a/sysdeps/m68k/nptl/thread_pointer.h b/sysdeps/m68k/nptl/thread_pointer.h
>> new file mode 100644
>> index 0000000000..08df6a8ac4
>> --- /dev/null
>> +++ b/sysdeps/m68k/nptl/thread_pointer.h
>> @@ -0,0 +1,30 @@
>> +/* __thread_pointer definition.  m68k version.
>> +   Copyright (C) 2021-2024 Free Software Foundation, Inc.
> 
> OK. Looks very similar to the other thread_pointer.h files, so I guess
> as a slightly modified "copy", the 2021-2024 copyright line is fine.
> 
>> +   This file is part of the GNU C Library.
>> +
>> +   The GNU C Library is free software; you can redistribute it and/or
>> +   modify it under the terms of the GNU Lesser General Public
>> +   License as published by the Free Software Foundation; either
>> +   version 2.1 of the License, or (at your option) any later version.
>> +
>> +   The GNU C Library is distributed in the hope that it will be useful,
>> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
>> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
>> +   Lesser General Public License for more details.
>> +
>> +   You should have received a copy of the GNU Lesser General Public
>> +   License along with the GNU C Library.  If not, see
>> +   <https://www.gnu.org/licenses/>.  */
>> +
>> +#ifndef _SYS_THREAD_POINTER_H
>> +#define _SYS_THREAD_POINTER_H
> 
> OK. Matches other files.
> 
>> +
>> +extern void * __m68k_read_tp (void);
> 
> OK. Corresponds to a get_thread_area system call.
> 
>> +
>> +static inline void *
>> +__thread_pointer (void)
>> +{
>> +  return __m68k_read_tp ();
>> +}
> 
> OK. Call it. Looks reasonable to me.
> 
>> +
>> +#endif /* _SYS_THREAD_POINTER_H */
> 
> OK.
> 
>> --
>> 2.43.0