Re: [PATCH v2 00/13] xfs: tracing: remove unused event xfs_reflink_cow_found

[Steven Rostedt <rostedt@goodmis.org>]

Should this go through the XFS tree, or should I take it?

-- Steve


On Mon, 16 Jun 2025 13:51:46 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> Trace events take up to 5K in memory for text and meta data. I have code that
> will trigger a warning when it detects unused tracepoints[1]. The XFS file
> system contains many events that are not called. Most of them used to be called
> but due to code refactoring the calls were removed but the trace events stayed
> behind.
> 
> Some events were added but never used. If they were recent, I just reported
> them, but if they were older, this series simply removes them.
> 
> One is called only when CONFIG_COMPACT is defined, so an #ifdef was placed
> around it.
> 
> Finally, one event is supposed to be a trace event class, but was created with
> the TRACE_EVENT() macro and not the DECLARE_EVENT_CLASS() macro. This works
> because a TRACE_EVENT() is simply a DECLARE_EVENT_CLASS() and DEFINE_EVENT()
> where the class and event have the same name. But as this was a mistake, the
> event created should not exist.
> 
> [1] https://patchwork.kernel.org/project/linux-trace-kernel/cover/20250612235827.011358765@goodmis.org/
> 
> Changes since v1: https://lore.kernel.org/linux-trace-kernel/20250612212405.877692069@goodmis.org/
> 
> - Removed the first patch that mistakenly removed xfs_reflink_cow_found
> 
> - Change subjects to start with lowercase
> 
> - Removed xfs_attr events that are used in an #if 0 section instead of
>   adding #if 0 around them
> 
> - I added: Reviewed-by: Christoph Hellwig <hch@lst.de>
>   to all patches but the one with the modified #if 0 as Christoph
>   said he looked at them all.
> 
> Steven Rostedt (13):
>       xfs: remove unused trace event xfs_attr_remove_iter_return
>       xfs: remove unused event xlog_iclog_want_sync
>       xfs: remove unused event xfs_ioctl_clone
>       xfs: remove unused xfs_reflink_compare_extents events
>       xfs: remove unused trace event xfs_attr_rmtval_set
>       xfs: remove unused xfs_attr events
>       xfs: remove unused event xfs_attr_node_removename
>       xfs: remove unused event xfs_alloc_near_error
>       xfs: remove unused event xfs_alloc_near_nominleft
>       xfs: remove unused event xfs_pagecache_inval
>       xfs: remove usused xfs_end_io_direct events
>       xfs: only create event xfs_file_compat_ioctl when CONFIG_COMPAT is configure
>       xfs: change xfs_xattr_class from a TRACE_EVENT() to DECLARE_EVENT_CLASS()
> 
> ----
>  fs/xfs/scrub/trace.h |  2 +-
>  fs/xfs/xfs_trace.h   | 68 ++--------------------------------------------------
>  2 files changed, 3 insertions(+), 67 deletions(-)