Re: [PATCH v2] rv: Fix multiple definition of __pcpu_unique_da_mon_this

[Steven Rostedt <rostedt@goodmis.org>]

FYI, please send new versions of a patch as a separate thread. Do not send
it as a reply to the first version. That makes it much more difficult for
maintainers to keep track of.

You should also add what changed since the first version:

> The refactoring in commit 30984ccf31b7 ("rv: Refactor da_monitor to
> minimise macros") replaced per-monitor unique variable names
> (da_mon_##name) with a fixed name (da_mon_this).
> 
> While this works for 'static' variables (each translation unit gets its
> own copy), DEFINE_PER_CPU internally generates a non-static dummy
> variable __pcpu_unique_<n> for each per-cpu definition. The requirement
> for this variable to be unique although static exists for modules on
> specific architectures (alpha) and if the kernel is built with
> CONFIG_DEBUG_FORCE_WEAK_PER_CPU (e.g. Fedora's debug kernel).
> 
> When multiple per-cpu monitors (e.g. sco and sts) are built-in
> simultaneously, they all produce the same __pcpu_unique_da_mon_this
> symbol, causing a link error:
> 
>   ld: kernel/trace/rv/monitors/sts/sts.o: multiple definition of
>       `__pcpu_unique_da_mon_this';
>       kernel/trace/rv/monitors/sco/sco.o: first defined here
> 
> Fix this by introducing a DA_MON_NAME macro that expands to a
> per-monitor unique name (da_mon_<MONITOR_NAME>) via the existing
> CONCATENATE helper. This restores the uniqueness that was present
> before the refactoring.
> 
> Fixes: 30984ccf31b7 ("rv: Refactor da_monitor to minimise macros")
> Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
> Signed-off-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
> ---

Changes since v1: https://lore.kernel.org/all/20260216074727.741822-1-mikhail.v.gavrilov@gmail.com/

- <list changes here>

>  include/rv/da_monitor.h | 16 +++++++++++-----
>  1 file changed, 11 insertions(+), 5 deletions(-)
> 
> diff --git a/include/rv/da_monitor.h b/include/rv/da_monitor.h
> index db11d41bb438..7511f5464c48 10064


This way this patch has a link to the previous version. Then when this
patch gets committed, it the commit has a link to this patch, and that
patch has a link to a previous version and the chain of updates is archived
nicely.

-- Steve