v3.1: opal/fifo: fix 128-bit atomic fifo on Power9 #5418
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This commit updates the atomic fifo code to fix a consistency issue observed on Power9 systems when builtin atomics are used. The cause was two things: 1) a missing write memory barrier in fifo push, and 2) a read ordering issue when reading the fifo head non-atomically. This commit fixes both issues and appears to correct then inconsistency. Signed-off-by: Nathan Hjelm <[email protected]> (cherry picked from commit 8b09010) Signed-off-by: Nathan Hjelm <[email protected]>
jsquyres
changed the title
gpaulsen
approved these changes
Jul 13, 2018
|
built and tested on Power9. This fixes the issue. Thanks! |
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This commit updates the atomic fifo code to fix a consistency issue
observed on Power9 systems when builtin atomics are used. The cause
was two things: 1) a missing write memory barrier in fifo push, and 2)
a read ordering issue when reading the fifo head non-atomically. This
commit fixes both issues and appears to correct then inconsistency.
Signed-off-by: Nathan Hjelm [email protected]
(cherry picked from commit 8b09010)
Signed-off-by: Nathan Hjelm [email protected]