User-space interrupts

Posted Oct 1, 2021 12:10 UTC (Fri) by droundy (guest, #4559)
In reply to: User-space interrupts by NYKevin
Parent article: User-space interrupts

Would it not be possible to service the interrupt and then finish the system call? Or would that put too strong a constraint on what could be done by the handler?

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User-space interrupts

Posted Oct 1, 2021 13:46 UTC (Fri) by mathstuf (subscriber, #69389) [Link] (1 responses)

The handler could twiddle with memory the syscall is working with from the userspace side, no? You'll need a context swap at least anyways so the handler has the right memory mappings.

User-space interrupts

Posted Oct 1, 2021 16:30 UTC (Fri) by nybble41 (subscriber, #55106) [Link]

Another thread in the same process can already change memory (and mappings) while the first thread is in a system call, either because a reschedule occurred during the system call or because the other thread is running on a different CPU. A signal handler doesn't seem like it would change anything in that regard.