SHMEM_CLEAR_CACHE_LINE_INV(3)

🎀 SHMEM_CLEAR_CACHE_LINE_INV 🎀

okay bestie, this one's from the Open MPI manual, and it's a whole bundle of cache-vibe-control functions. it's giving "legacy but iconic". sit down, hydrate, let's go ✨

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✨ 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 💅

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🦋 SYNOPSIS 🦋

so there's a C/C++ side and a Fortran side, and they're both invited to the party:

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)

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💖 DESCRIPTION 💖

here's the one argument that gets passed to the cache line control routines, and she's the main character:

• target — a data object that's local to the processing element (PE). target can be of any noncharacter type. and if you're doing Fortran? it can be of any kind. periodt. ✨

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🌸 the whole lineup, one by one 🌸

• shmem_clear_cache_inv — disables automatic cache coherency mode that was previously enabled by shmem_set_cache_inv or shmem_set_cache_line_inv. it's the "okay we're done here" button 🫶
• shmem_clear_cache_line_inv — disables automatic cache coherency mode for the cache line associated with the address of target only. just that one line, bestie. focused. 💅
• shmem_set_cache_inv — enables the OpenSHMEM API to automatically decide the best strategy for cache coherency. she's smart, she handles it 👑
• shmem_set_cache_line_inv — enables automatic cache coherency mode for the cache line associated with the address of target only. again. just the one line 😌
• shmem_clear_cache_inv — disables automatic cache coherency mode previously enabled by shmem_set_cache_inv or shmem_set_cache_line_inv. (yes she's listed twice, no I'm not skipping her, we keep EVERYTHING in this house 🫡)
• shmem_udcflush — makes the entire user data cache coherent. the whole thing. no half measures 🧚
• shmem_udcflush_line — makes coherent the cache line that corresponds with the address specified by target. just the one line, again. consistency is her brand ✨

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📝 NOTES 📝

these routines have been retained for improved backward compatibility with legacy architectures. so like — they're still here, still invited, still valid, just a little vintage-core 🌈

See also:

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

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👑 Copyright 👑

2003-2026, The Open MPI Community

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aaaand that's the whole page, bestie 💜 no cap, you now understand cache invalidation controls better than half the internet. slay responsibly. 🦋💅

from the Open MPI crew — page dated Sep 10, 2026, filed under SHMEM_CLEAR_CACHE_LINE_INV(3). mwah 🎀