Messages in this thread | ![/](/images/icornerl.gif) | | From | "Luck, Tony" <> | Subject | RE: [PATCH] x86/mce: Dynamically size space for machine check records | Date | Thu, 29 Feb 2024 18:38:58 +0000 |
| |
> Wouldn't having dedup actually increase the time we spend #MC context? > Comparing the new MCE record against each existing record in the > genpool.
Yes, dedup would take extra time (increasing linearly with the number of pending errors that were not filtered out by the dedup process).
> AFAIK, MCEs cannot be nested. Correct me if I am wrong here.
Can't be nested on the same CPU. But multiple CPUs may take a local machine check simultaneously. Local machine check is opt-in on Intel, I believe it is default on AMD.
Errors can also be signaled with CMCI.
> In a flood situation, like the one described above, that is exactly > what may happen: An MCE coming in while the dedup mechanism is > underway (in #MC context).
In a flood of errors it would be complicated to synchronize dedup filtering on multiple CPUs. The trade-off between trying to get that code right, and just allocating a few extra Kbytes of memory would seem to favor allocating more memory.
-- Thanks, Avadhut Naik
| ![\](/images/icornerr.gif) |