From: Johannes Weiner <hannes@cmpxchg.org>
To: Minchan Kim <minchan@kernel.org>
Cc: Nhat Pham <nphamcs@gmail.com>,
akpm@linux-foundation.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org, ngupta@vflare.org,
senozhatsky@chromium.org, sjenning@redhat.com, ddstreet@ieee.org,
vitaly.wool@konsulko.com
Subject: Re: [PATCH v5 4/6] zsmalloc: Add a LRU to zs_pool to keep track of zspages in LRU order
Date: Fri, 18 Nov 2022 15:05:04 -0500 [thread overview]
Message-ID: <Y3flcAXNxxrvy3ZH@cmpxchg.org> (raw)
In-Reply-To: <Y3fdsTDFgCzhcDwo@google.com>
On Fri, Nov 18, 2022 at 11:32:01AM -0800, Minchan Kim wrote:
> On Fri, Nov 18, 2022 at 10:24:05AM -0800, Nhat Pham wrote:
> > @@ -1444,6 +1473,11 @@ unsigned long zs_malloc(struct zs_pool *pool, size_t size, gfp_t gfp)
> >
> > /* We completely set up zspage so mark them as movable */
> > SetZsPageMovable(pool, zspage);
> > +out:
> > +#ifdef CONFIG_ZPOOL
> > + /* Move the zspage to front of pool's LRU */
> > + move_to_front(pool, zspage);
> > +#endif
> > spin_unlock(&pool->lock);
>
> Please move the move_to_front into zs_map_object with ZS_MM_WO with
> comment with "why we are doing only for WO case".
I replied to the other thread, but I disagree with this request.
The WO exception would be as zswap-specific as is the
rotate-on-alloc. It doesn't make the resulting zsmalloc code any
cleaner or more generic, just weird in a slightly different way.
On the other hand, it makes zsmalloc deviate from the other backends
and introduces new callchains that invalidate thousands of machine
hours of production testing of this code.
next prev parent reply other threads:[~2022-11-18 20:04 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-18 18:24 [PATCH v5 0/6] Implement writeback for zsmalloc Nhat Pham
2022-11-18 18:24 ` [PATCH v5 1/6] zswap: fix writeback lock ordering " Nhat Pham
2022-11-18 18:24 ` [PATCH v5 2/6] zpool: clean out dead code Nhat Pham
2022-11-18 18:24 ` [PATCH v5 3/6] zsmalloc: Consolidate zs_pool's migrate_lock and size_class's locks Nhat Pham
2022-11-18 18:24 ` [PATCH v5 4/6] zsmalloc: Add a LRU to zs_pool to keep track of zspages in LRU order Nhat Pham
2022-11-18 19:32 ` Minchan Kim
2022-11-18 20:05 ` Johannes Weiner [this message]
2022-11-18 21:35 ` Minchan Kim
2022-11-18 23:23 ` Johannes Weiner
2022-11-18 18:24 ` [PATCH v5 5/6] zsmalloc: Add zpool_ops field to zs_pool to store evict handlers Nhat Pham
2022-11-18 19:33 ` Minchan Kim
2022-11-18 18:24 ` [PATCH v5 6/6] zsmalloc: Implement writeback mechanism for zsmalloc Nhat Pham
2022-11-18 21:01 ` Minchan Kim
2022-11-18 22:08 ` Nhat Pham
2022-11-18 22:38 ` Minchan Kim
2022-11-19 0:37 ` Nhat Pham
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=Y3flcAXNxxrvy3ZH@cmpxchg.org \
--to=hannes@cmpxchg.org \
--cc=akpm@linux-foundation.org \
--cc=ddstreet@ieee.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=minchan@kernel.org \
--cc=ngupta@vflare.org \
--cc=nphamcs@gmail.com \
--cc=senozhatsky@chromium.org \
--cc=sjenning@redhat.com \
--cc=vitaly.wool@konsulko.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox