4ea3fa9dd2
Patch series "zswap same-filled and limit checking cleanups", v3. Miscellaneous cleanups for limit checking and same-filled handling in the store path. This series was broken out of the "zswap: store zero-filled pages more efficiently" series [1]. It contains the cleanups and drops the main functional changes. [1]https://lore.kernel.org/lkml/20240325235018.2028408-1-yosryahmed@google.com/ This patch (of 4): The cleanup code in zswap_store() is not pretty, particularly the 'shrink' label at the bottom that ends up jumping between cleanup labels. Instead of having a dedicated label to shrink the pool, just use zswap_pool_reached_full directly to figure out if the pool needs shrinking. zswap_pool_reached_full should be true if and only if the pool needs shrinking. The only caveat is that the value of zswap_pool_reached_full may be changed by concurrent zswap_store() calls between checking the limit and testing zswap_pool_reached_full in the cleanup code. This is fine because: - If zswap_pool_reached_full was true during limit checking then became false during the cleanup code, then someone else already took care of shrinking the pool and there is no need to queue the worker. That would be a good change. - If zswap_pool_reached_full was false during limit checking then became true during the cleanup code, then someone else hit the limit meanwhile. In this case, both threads will try to queue the worker, but it never gets queued more than once anyway. Also, calling queue_work() multiple times when the limit is hit could already happen today, so this isn't a significant change in any way. Link: https://lkml.kernel.org/r/20240413022407.785696-1-yosryahmed@google.com Link: https://lkml.kernel.org/r/20240413022407.785696-2-yosryahmed@google.com Signed-off-by: Yosry Ahmed <yosryahmed@google.com> Reviewed-by: Nhat Pham <nphamcs@gmail.com> Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: "Maciej S. Szmigiero" <mail@maciej.szmigiero.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.