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([2001:288:7001:2703:f8d5:8589:bb53:d71d]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-b49cb8c369csm9566177a12.24.2025.08.26.09.17.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 26 Aug 2025 09:17:46 -0700 (PDT) From: Guan-Chun Wu <409411716@gms.tku.edu.tw> To: akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org, 409411716@gms.tku.edu.tw Subject: [PATCH v2] btree: simplify merge logic by using btree_last() return value Date: Wed, 27 Aug 2025 00:17:41 +0800 Message-Id: <20250826161741.686704-1-409411716@gms.tku.edu.tw> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Previously btree_merge() called btree_last() only to test existence, then performed an extra btree_lookup() to fetch the value. This patch changes it to directly use the value returned by btree_last(), avoiding redundant lookups and simplifying the merge loop. v2: - Update subject to clarify this is a simplification, not a bug fix Signed-off-by: Guan-Chun Wu <409411716@gms.tku.edu.tw> --- lib/btree.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/lib/btree.c b/lib/btree.c index bb81d3393ac5..9c80c0c7bba8 100644 --- a/lib/btree.c +++ b/lib/btree.c @@ -653,9 +653,9 @@ int btree_merge(struct btree_head *target, struct btree= _head *victim, * walks to remove a single object from the victim. */ for (;;) { - if (!btree_last(victim, geo, key)) + val =3D btree_last(victim, geo, key); + if (!val) break; - val =3D btree_lookup(victim, geo, key); err =3D btree_insert(target, geo, key, val, gfp); if (err) return err; --=20 2.34.1