[lttng-dev] Is it possible to disable recording the CPU id for USTs?

2024-06-18 Thread Aditya Kurdunkar via lttng-dev
Hello, Please bear with me if this is a naive question. I am working on an embedded ARM chip (1GB ram, 2CPUs) where I want to collect trace events for a long duration of time. From the research that I have done (mostly reading papers on LTTng tracing, conference talks and documentation) I have see

Re: [lttng-dev] Is it possible to disable recording the CPU id for USTs?

2024-06-18 Thread Kienan Stewart via lttng-dev
Hi Aditya, On 6/18/24 8:55 AM, Aditya Kurdunkar via lttng-dev wrote: Hello, Please bear with me if this is a naive question. I am working on an embedded ARM chip (1GB ram, 2CPUs) where I want to collect trace events for a long duration of time. From the research that I have done (mostly read

Re: [lttng-dev] Is it possible to disable recording the CPU id for USTs?

2024-06-18 Thread Kienan Stewart via lttng-dev
Hi Aditya, I want to add a further detail. While neither arm32 nor arm64 have support for quick lookups of the current cpu id in vDSO, I think that if you are using a recent linux kernel (>= 4.18) with a recent glibc (>= 2.32 with RSEQ_SIG defined) sched_getcpu should use RSEQ instead, and it