SHMEM_CACHE(3)

okay bestie, this is SHMEM_CACHE(3) from the Open MPI manual — the data cache utilities page, and it's lowkey iconic. 💾✨

✨ NAME ✨

• shmem_clear_cache_inv(3)
• shmem_set_cache_inv(3)
• shmem_set_cache_line_inv(3)
• shmem_udcflush(3)
• shmem_udcflush_line(3)

Controls data cache utilities 🎀 (and yep, shmem_clear_cache_line_inv shows up in the synopsis and description below — the page is built like that, don't @ me.)

🌈 SYNOPSIS 🌈

C or C++:

#include <mpp/shmem.h>

void shmem_clear_cache_inv(void);
void shmem_clear_cache_line_inv(void *target);
void shmem_set_cache_inv(void);
void shmem_set_cache_line_inv(void *target);
void shmem_udcflush(void);
void shmem_udcflush_line(void *target);

Fortran:

INCLUDE "mpp/shmem.fh"

CALL SHMEM_CLEAR_CACHE_INV
CALL SHMEM_CLEAR_CACHE_LINE_INV(target)
CALL SHMEM_SET_CACHE_INV
CALL SHMEM_SET_CACHE_LINE_INV(target)

CALL SHMEM_UDCFLUSH
CALL SHMEM_UDCFLUSH_LINE(target)

🎀 DESCRIPTION 🎀

The following argument is passed to the cache line control routines:

• target — a data object that is local to the processing element (PE). target can be of any noncharacter type. If you're using Fortran, it can be of any kind. 🎯

Now for the main character functions:

• shmem_clear_cache_inv — disables automatic cache coherency mode that was previously enabled by shmem_set_cache_inv or shmem_set_cache_line_inv.
• shmem_clear_cache_line_inv — disables automatic cache coherency mode for the cache line associated with the address of target only.
• shmem_set_cache_inv — enables the OpenSHMEM API to automatically decide the best strategy for cache coherency.
• shmem_set_cache_line_inv — enables automatic cache coherency mode for the cache line associated with the address of target only.
• shmem_clear_cache_inv — yes, again: disables automatic cache coherency mode previously enabled by shmem_set_cache_inv or shmem_set_cache_line_inv. (The original really does list this twice, and we respect the repetition. 💅)
• shmem_udcflush — makes the entire user data cache coherent.
• shmem_udcflush_line — makes coherent the cache line that corresponds with the address specified by target.

🧚 NOTES 🧚

These routines have been retained for improved backward compatability with legacy architectures. 🧓✨

🔥 SEE ALSO 🔥

• intro_shmem(3)
• shmem_put(3)
• shmem_swap(3)

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signed off from the gitclone source, version Unreleased developer copy — no date in this footer, bestie, but the vibes are immaculate 🫶💖