Re: [PATCH v37 3/4] scsi: ufs: Prepare HPB read for cached sub-region

From: "정요한(JOUNG YOHAN) Mobile SE" <yohan.joung@sk.com>
To: "daejun7.park@samsung.com" <daejun7.park@samsung.com>
Cc: "alim.akhtar@samsung.com" <alim.akhtar@samsung.com>,
	"asutoshd@codeaurora.org" <asutoshd@codeaurora.org>,
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	"최재영(CHOI JAE YOUNG) Mobile SE" <jaeyoung21.choi@sk.com>
Subject: Re: [PATCH v37 3/4] scsi: ufs: Prepare HPB read for cached sub-region
Date: Fri, 11 Jun 2021 05:07:39 +0000	[thread overview]
Message-ID: <29bb775275b941c08c3f3f0d835620fe@sk.com> (raw)

>+	/*
>+	 * If the region state is active, mctx must be allocated.
>+	 * In this case, check whether the region is evicted or
>+	 * mctx allcation fail.
>+	 */
>+	if (unlikely(!srgn->mctx)) {
>+		dev_err(&hpb->sdev_ufs_lu->sdev_dev,
>+			"no mctx in region %d subregion %d.\n",
>+			srgn->rgn_idx, srgn->srgn_idx);
>+		return true;
>+	}
>+
>+	if ((srgn_offset + cnt) > bitmap_len)
>+		bit_len = bitmap_len - srgn_offset;
>+	else
>+		bit_len = cnt;
>+
>+	if (find_next_bit(srgn->mctx->ppn_dirty, bitmap_len,
>+			  srgn_offset) < bit_len + srgn_offset)
>+		return true;
>+

It seems unnecessary to search through bitmap_len
How about searching by transfer size?

if (find_next_bit(srgn->mctx->ppn_dirty,
              bit_len + srgn_offset, srgn_offset) < bit_len + srgn_offset)

Thanks
Yohan