Re:A lock-free ring-buffer with contiguous reservations (2019)
by mrcode007 on Thursday February 29, 2024 @11:20PM
(#39558502)
Yes, this is correct and the most overlooked aspect and reason for the misnomer. Atomics imply locking at the cpu. Depending on the CPU the lock happens either for the entire memory bus (pre Intel P6 on x86) or as part of snoop disable bits on relevant cache lines in the snooping protocol
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Re:A lock-free ring-buffer with contiguous reservations (2019)
by DannyBee on Friday March 01, 2024 @12:10AM
(#39558728)
It's not a misnomer, it's just a bad term of art. When it was coined folks were well aware that atomics locked at the CPU level.
Re:A lock-free ring-buffer with contiguous reservations (2019)
by mrcode007 on Friday March 01, 2024 @01:00AM
(#39558989)
“In discussing the question, he used to liken the case to that of the boy who, when asked how many legs his calf would have if he called its tail a leg, replied, ” Five,” to which the prompt response was made that calling the tail a leg would not make it a leg.”
Re:A lock-free ring-buffer with contiguous reservations (2019)
by gpderetta on Friday March 01, 2024 @06:25AM
(#39560767)
The "locking" happening on the CPU level is very different from the software level locking, as it is guaranteed by the hardware to be bounded (technically bus arbiters are not guaranteed to complete in finite time, but they are astronomically unlikely to do so).