Re: [PATCH v5 06/10] Uprobes: Support SDT markers having reference count (semaphore)

From: Ravi Bangoria
Date: Wed Jul 04 2018 - 02:07:37 EST


Hi Srikar,

On 07/02/2018 09:31 PM, Srikar Dronamraju wrote:

> 2. ref_ctr_offset is necessarily a consumer property, its not a uprobe
> property at all.


Sorry to ask this after agreeing :P

Initially, I thought this point is right. But after thinking more on this,
it seems wrong to me. Ex a python SDT probe:

Provider: python
Name: function__entry
Location: 0x0000000000140de4, Base: 0x00000000001ddfb0, Semaphore: 0x0000000000268320

Here, "Semaphore" field is what we are referring to as reference counter.
Basically reference counter's job is to gate invocation of uprobe and
thus ref_ctr_offset becomes a uprobe property, not the consumer property.
No? Am I missing anything?

Thanks,
Ravi