On Thu, 26 Dec 2024 15:07:39 -0800 Suren Baghdasaryan surenb@google.com wrote:
On Thu, Dec 26, 2024 at 3:01 PM Andrew Morton akpm@linux-foundation.org wrote:
On Thu, 26 Dec 2024 13:16:39 -0800 Suren Baghdasaryan surenb@google.com wrote:
When memory allocation profiling is disabled, there is no need to swap allocation tags during migration. Skip it to avoid unnecessary overhead.
Fixes: e0a955bf7f61 ("mm/codetag: add pgalloc_tag_copy()") Signed-off-by: Suren Baghdasaryan surenb@google.com Cc: stable@vger.kernel.org
Are these changes worth backporting? Some indication of how much difference the patches make would help people understand why we're proposing a backport.
The first patch ("alloc_tag: avoid current->alloc_tag manipulations when profiling is disabled") I think is worth backporting. It eliminates about half of the regression for slab allocations when profiling is disabled.
um, what regression? The changelog makes no mention of this. Please send along a suitable Reported-by: and Closes: and a summary of the benefits so that people can actually see what this patch does, and why.