[DTrace-devel] [PATCH v2 1/6] Deferred attach of underlying USDT probes

[Eugene Loh]

I am withdrawing this patch;  the rest of the 6-patch series is still 
good since it deals with tests.  With Kris's suggestion of 
dt_provider_discover(), the "deferred attach" will be absorbed into 
earlier patches.  The revised patches will be:

v2->v3 02/19 Add a hook for a provider-specific "update" function
     and will be renamed "Add a dt_provider_discover() function"

v5->v6 07/19 Create the BPF usdt_names and usdt_prids maps

v3->v4 09/19 Use usdt_prids map to call clauses conditionally for USDT 
probes

v2->v3 14/19 Ignore clauses in USDT trampoline if we know they are 
impossible

On 10/9/24 01:45, eugene.loh at oracle.com wrote:
> From: Eugene Loh <eugene.loh at oracle.com>
>
> We would like dtrace to trace USDT processes that start
> even after the dtrace session has been launched.  In that
> case, the underlying probe cannot be attached when dtrace
> starts up;  rather, the BPF program must be attached once
> the USDT process has been detected.
>
> Therefore:
>
> *)  Make dt_bpf_load_prog() callable outside of dt_bpf.c.
>
> *)  Have update_uprobe() call dt_construct(), dt_link(),
>      dt_bpf_load_prog(), and attach() for any new underlying
>      probes.
>
> Signed-off-by: Eugene Loh <eugene.loh at oracle.com>