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Merged
merged 9 commits into from
May 14, 2025
Merged

posix: implement xsi_single_process and posix_clock_selection #89068

merged 9 commits into from
May 14, 2025

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@cfriedt cfriedt commented Apr 25, 2025 •
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  • posix: env: create z_getenv()..z_setenv() convenience functions
  • posix: env: move most implementations to env-common.c
  • posix: clock: create z_clock_gettime().. convenience functions.
  • posix: clock: move most implementations to clock_common.c
  • posix: implement the xsi_single_process option group
  • tests: posix: add test for the xsi_single_process option group
  • doc: posix: add doc for xsi_single_process option group
  • posix: implement the posix_clock_selection option group
  • tests: posix: add posix_clock_selection testsuite

Notable Changes

  • gettimeofday() is moved to the XSI_SINGLE_PROCESS Option Group (which is according to spec)
  • Remove artificial dependencies POSIX_SINGLE_PROCESS and POSIX_TIMERS from XSI_SINGLE_PROCESS
    • POSIX Option Groups should be independent
  • env functions required by XSI_SINGLE_PROCESS and POSIX_SINGLE_PROCESS moved to env-common.c
  • clock functions required by XSI_SINGLE_PROCESS, POSIX_TIMERS, and POSIX_CLOCK_SELECTION moved to clock-common.c
  • Clock base now protected by sys_sem instead of spinlock (to better support userspace)

Notable Observations

  • z_ functions will get replaced at a later date when we have resolution of Drop z_ prefix as identifier for internal/private functions and revert back to _  #58007
  • tests/lib/time should really be a part of tests/lib/c_lib since it tests the time() C89 function
    • Big problem is that it pulls in CONFIG_POSIX_TIMERS and CONFIG_XSI_SINGLE_PROCESS
    • Why? in the common libc implementationtime() uses clock_gettime(), which is maybe fine if the assumption is that one is using POSIX or running on top of a POSIX OS anyway, but that's definitely not the case in Zephyr.
      • it forms a dependency cycle at the API level
      • the z_clock_gettime() and similar functions in this PR could easily become a core part of Zephyr (i.e. promoted to k_clock_gettime() etc)
      • the dependency cycle (between libc and posix) would then be resolved via mutual dependency (Zephyr)
  • asctime_r(), ctime_r(), gmtime_r(), localtime_r() should all probably be moved to POSIX_C_LANG_SUPPORT_R since they are not part of ISO C until C23, which is not yet proposed in RFC: C11 (or C17) requirement #30105

Should be merged after #89063, #89107

@cfriedt cfriedt force-pushed the issue/88556/posix-gettimeofday-is-not-a-part-of-posix-timers-but-xsi-single-process branch 3 times, most recently from 247ce21 to d41e9e4 Compare April 25, 2025 10:39
@cfriedt cfriedt changed the title poxix: env: create z_getenv()..z_setenv() convenience functions poxix: implement xsi_single_process and posix_clock_selection Apr 25, 2025
@cfriedt cfriedt force-pushed the issue/88556/posix-gettimeofday-is-not-a-part-of-posix-timers-but-xsi-single-process branch 7 times, most recently from ff4b6b4 to 0fa03fe Compare April 25, 2025 12:53
@cfriedt cfriedt changed the title poxix: implement xsi_single_process and posix_clock_selection posix: implement xsi_single_process and posix_clock_selection Apr 25, 2025
@cfriedt cfriedt force-pushed the issue/88556/posix-gettimeofday-is-not-a-part-of-posix-timers-but-xsi-single-process branch 2 times, most recently from 84db803 to 4144abe Compare April 26, 2025 12:15
@cfriedt cfriedt force-pushed the issue/88556/posix-gettimeofday-is-not-a-part-of-posix-timers-but-xsi-single-process branch 5 times, most recently from 7f7d093 to 3f894b8 Compare May 3, 2025 09:40
@cfriedt cfriedt requested review from nashif, jukkar, ycsin and JordanYates May 3, 2025 10:34
@cfriedt cfriedt marked this pull request as ready for review May 3, 2025 10:34
@cfriedt cfriedt requested a review from carlescufi May 3, 2025 10:41
cfriedt
cfriedt commented May 3, 2025
View reviewed changes
ycsin
ycsin reviewed May 4, 2025
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cfriedt added 9 commits May 4, 2025 20:31
@cfriedt
posix: env: create z_getenv()..z_setenv() convenience functions
78785cd 
To facilitate adding putenv in a separate compilation unit,
make z_getenv(), z_getenv_r(), z_setenv(), and z_unsetenv()
convenience functions.

Signed-off-by: Chris Friedt <cfriedt@tenstorrent.com>
@cfriedt
posix: env: move most implementations to env-common.c
f472915 
Move most implementations to env-common.c in preparation for adding
putenv.c .

We also take this as an opportunity to switch from using k_spinlock
to sys_sem.

Signed-off-by: Chris Friedt <cfriedt@tenstorrent.com>
@cfriedt
posix: clock: create z_clock_gettime().. convenience functions.
e894c7a 
To facilitate moving gettimeofday() and clock_nanosleep() to separate
compilation units, make z_clock_nanosleep(), z_clock_gettime(),
and z_clock_settime() convenience functions.

Signed-off-by: Chris Friedt <cfriedt@tenstorrent.com>
@cfriedt
posix: clock: move most implementations to clock_common.c
81a2745 
Move most implementations to clock_common.c in preparation for
moving gettimeofday() and clock_nanosleep() to different compilation
units.

We also take this as an opportunity to switch from using k_spinlock
to sys_sem.

Signed-off-by: Chris Friedt <cfriedt@tenstorrent.com>
@cfriedt
posix: implement the XSI_SINGLE_PROCESS Option Group
9781fde 
gettimeofday() was already implemented, but incorrectly lumped into
POSIX_TIMERS.

putenv() is really just a wrapper around setenv().

The only one left to implement was gethostid() which was relatively
trivial.

Signed-off-by: Chris Friedt <cfriedt@tenstorrent.com>
@cfriedt
tests: posix: add test for the xsi_single_process option group
0a4e085 
Add tests for the XSI_SINGLE_PROCESS Option Group.

Signed-off-by: Chris Friedt <cfriedt@tenstorrent.com>
@cfriedt
doc: posix: add doc for XSI_SINGLE_PROCESS Option Group
46fdf72 
Mark the XSI_SINGLE_PROCESS Option Group as supported.

Signed-off-by: Chris Friedt <cfriedt@tenstorrent.com>
@cfriedt
posix: implement the POSIX_CLOCK_SELECTION Option Group
aed230e 
Implement the POSIX_CLOCK_SELECTION Option Group.

This was mostly already done, but compiled / linked in the wrong places.

E.g. pthread_condattr_getclock() and pthread_condattr_setclock() were
in pthread.c and part of POSIX_THREADS_BASE. clock_nanosleep() was in
clock.c and part of POSIX_TIMERS.

This change builds them as part of clock_selection.c with
CONFIG_POSIX_CLOCK_SELECTION.

Signed-off-by: Chris Friedt <cfriedt@tenstorrent.com>
@cfriedt
tests: posix: add posix_clock_selection testsuite
b8c8acb 
Add a testsuite for the POSIX_CLOCK_SELECTION Option Group which
consists of clock_nanosleep(), pthread_condattr_getclock(), and
pthread_condattr_setclock().

Signed-off-by: Chris Friedt <cfriedt@tenstorrent.com>
@cfriedt cfriedt force-pushed the issue/88556/posix-gettimeofday-is-not-a-part-of-posix-timers-but-xsi-single-process branch from 3f894b8 to b8c8acb Compare May 5, 2025 00:39
@cfriedt cfriedt requested a review from ycsin May 5, 2025 02:04
ycsin
ycsin approved these changes May 5, 2025
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LGTM, thanks @cfriedt

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cfriedt commented May 11, 2025

@nashif, @andyross - the bot assigned his PR to you, and so I think it needs one or both if your approvals in order to be merged.

Feel free to reassign if you prefer.

@cfriedt cfriedt assigned cfriedt and unassigned nashif and andyross May 13, 2025
@nashif nashif merged commit 3c7e43f into zephyrproject-rtos:main May 14, 2025
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@cfriedt cfriedt mentioned this pull request May 14, 2025
Merged
cfriedt added a commit to cfriedt/zephyr that referenced this pull request May 14, 2025
@cfriedt
samples: net: lwm2m: depend on xsi single process for gettimeofday()
6901edb 
https://github.com/zephyrproject-rtos/zephyr/actions/runs/\
15014534061/job/42189411225

We were seeing a linker error of the form

```
picolibc/x86_64-zephyr-elf/lib/32/libc.a(libc_time_time.c.o): \
  in function `time':
time.c:(.text.time+0x11): undefined reference to `gettimeofday'
```

Update the dependency from CONFIG_POSIX_TIMERS to
CONFIG_XSI_SINGLE_PROCESS for gettimeofday().

Note: this is really only a workaround. The proper solution would
be to have libc functions not depend on POSIX functions.

Specifically, here

https://github.com/zephyrproject-rtos/picolibc/blob/\
51a8b32857e75345c37652a80b5cda98b28d69e5/newlib/libc/time/\
time.c#L54

and here

https://github.com/zephyrproject-rtos/zephyr/blob/\
3a4e128/lib/libc/common/\
source/time/time.c#L17

Also mentioned in zephyrproject-rtos#89068

Signed-off-by: Chris Friedt <cfriedt@tenstorrent.com>
@cfriedt cfriedt mentioned this pull request May 14, 2025
Merged
cfriedt added a commit to cfriedt/zephyr that referenced this pull request May 15, 2025
@cfriedt
samples: net: lwm2m: depend on xsi single process for gettimeofday()
4b72cab 
https://github.com/zephyrproject-rtos/zephyr/actions/runs/\
15014534061/job/42189411225

We were seeing a linker error of the form

```
picolibc/x86_64-zephyr-elf/lib/32/libc.a(libc_time_time.c.o): \
  in function `time':
time.c:(.text.time+0x11): undefined reference to `gettimeofday'
```

Update the dependency from CONFIG_POSIX_TIMERS to
CONFIG_XSI_SINGLE_PROCESS for gettimeofday().

Note: this is really only a workaround. The proper solution would
be to have libc functions not depend on POSIX functions.

Specifically, here

https://github.com/zephyrproject-rtos/picolibc/blob/\
51a8b32857e75345c37652a80b5cda98b28d69e5/newlib/libc/time/\
time.c#L54

and here

https://github.com/zephyrproject-rtos/zephyr/blob/\
3a4e128/lib/libc/common/\
source/time/time.c#L17

Also mentioned in zephyrproject-rtos#89068

Signed-off-by: Chris Friedt <cfriedt@tenstorrent.com>
kartben pushed a commit that referenced this pull request May 15, 2025
@cfriedt @kartben
samples: net: lwm2m: depend on xsi single process for gettimeofday()
3934461 
https://github.com/zephyrproject-rtos/zephyr/actions/runs/\
15014534061/job/42189411225

We were seeing a linker error of the form

```
picolibc/x86_64-zephyr-elf/lib/32/libc.a(libc_time_time.c.o): \
  in function `time':
time.c:(.text.time+0x11): undefined reference to `gettimeofday'
```

Update the dependency from CONFIG_POSIX_TIMERS to
CONFIG_XSI_SINGLE_PROCESS for gettimeofday().

Note: this is really only a workaround. The proper solution would
be to have libc functions not depend on POSIX functions.

Specifically, here

https://github.com/zephyrproject-rtos/picolibc/blob/\
51a8b32857e75345c37652a80b5cda98b28d69e5/newlib/libc/time/\
time.c#L54

and here

https://github.com/zephyrproject-rtos/zephyr/blob/\
3a4e128/lib/libc/common/\
source/time/time.c#L17

Also mentioned in #89068

Signed-off-by: Chris Friedt <cfriedt@tenstorrent.com>
jlbwoods pushed a commit to jlbwoods/zephyr that referenced this pull request May 15, 2025
@cfriedt @johnlinwiz
samples: net: lwm2m: depend on xsi single process for gettimeofday()
0a54526 
https://github.com/zephyrproject-rtos/zephyr/actions/runs/\
15014534061/job/42189411225

We were seeing a linker error of the form

```
picolibc/x86_64-zephyr-elf/lib/32/libc.a(libc_time_time.c.o): \
  in function `time':
time.c:(.text.time+0x11): undefined reference to `gettimeofday'
```

Update the dependency from CONFIG_POSIX_TIMERS to
CONFIG_XSI_SINGLE_PROCESS for gettimeofday().

Note: this is really only a workaround. The proper solution would
be to have libc functions not depend on POSIX functions.

Specifically, here

https://github.com/zephyrproject-rtos/picolibc/blob/\
51a8b32857e75345c37652a80b5cda98b28d69e5/newlib/libc/time/\
time.c#L54

and here

https://github.com/zephyrproject-rtos/zephyr/blob/\
3a4e128/lib/libc/common/\
source/time/time.c#L17

Also mentioned in zephyrproject-rtos#89068

Signed-off-by: Chris Friedt <cfriedt@tenstorrent.com>
@cfriedt cfriedt mentioned this pull request May 16, 2025
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