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From:   Daeho Jeong <daeho43@gmail.com>
Date:   Wed, 9 Sep 2020 13:43:35 +0900
Message-ID: <CACOAw_wHONVJL438_Akvo3wZewJeVKiT_8LqW0EXULxAscpGjA@mail.gmail.com>
Subject: Question about STEP_DECOMPRESS_NOWQ
To:     linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net, kernel-team@android.com
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Hi Chao,

I have a question about the below flag for decompression.

STEP_DECOMPRESS_NOWQ,           /* handle normal cluster data inplace */

According to the comment, you added this for using inplace
decompression but inplace decompression mode is not being activated
now, since we are setting STEP_DECOMPRESS right after bio_add_page().

                if (bio_add_page(bio, page, blocksize, 0) < blocksize)
                        goto submit_and_realloc;

                /* tag STEP_DECOMPRESS to handle IO in wq */
                ctx = bio->bi_private;
                if (!(ctx->enabled_steps & (1 << STEP_DECOMPRESS)))
                        ctx->enabled_steps |= 1 << STEP_DECOMPRESS;

Did you mean to deactivate inplace decompression mode on purpose,
since it had an issue? I am a little bit confused about this.