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([2403:18c0:5:3e0:98c6:7dff:fe56:ac2b]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-224109dd627sm57045605ad.50.2025.03.08.23.59.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 08 Mar 2025 23:59:03 -0800 (PST) From: Sun YangKai To: linux-btrfs@vger.kernel.org Cc: Sun YangKai Subject: [PATCH 2/3] btrfs: remove unnecessary 'found_key' local variable in btrfs_search_forward() Date: Sun, 9 Mar 2025 15:58:00 +0800 Message-ID: <20250309075820.30999-3-sunk67188@gmail.com> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250309075820.30999-1-sunk67188@gmail.com> References: <20250309075820.30999-1-sunk67188@gmail.com> Precedence: bulk X-Mailing-List: linux-btrfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The 'found_key' variable was only used to temporarily store a key value before copying it to 'min_key' at the end of the function when returning success (ret=0). This commit optimizes the code by: 1. Eliminating the intermediate 'found_key' variable 2. Directly populating 'min_key' at the exact loop exit points where ret=0 is set 3. Removing the final memcpy operation in the return path This change improves code clarity by: - Removing redundant variable usage - Simplifying the success path logic - Reducing memory operations The found key value is now stored directly into the destination 'min_key' structure at the point of discovery, maintaining identical functionality while: - Eliminating an unnecessary memory copy - Reducing code complexity Signed-off-by: Sun YangKai --- fs/btrfs/ctree.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 3dc5a35dd19b..1dc59dc3b708 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -4608,7 +4608,6 @@ int btrfs_search_forward(struct btrfs_root *root, struct btrfs_key *min_key, u64 min_trans) { struct extent_buffer *cur; - struct btrfs_key found_key; int slot; int sret; u32 nritems; @@ -4644,7 +4643,8 @@ int btrfs_search_forward(struct btrfs_root *root, struct btrfs_key *min_key, goto find_next_key; ret = 0; path->slots[level] = slot; - btrfs_item_key_to_cpu(cur, &found_key, slot); + /* save our key for returning back */ + btrfs_item_key_to_cpu(cur, min_key, slot); goto out; } if (sret && slot > 0) @@ -4679,11 +4679,11 @@ int btrfs_search_forward(struct btrfs_root *root, struct btrfs_key *min_key, goto out; } } - /* save our key for returning back */ - btrfs_node_key_to_cpu(cur, &found_key, slot); path->slots[level] = slot; if (level == path->lowest_level) { ret = 0; + /* save our key for returning back */ + btrfs_node_key_to_cpu(cur, min_key, slot); goto out; } cur = btrfs_read_node_slot(cur, slot); @@ -4702,7 +4702,6 @@ int btrfs_search_forward(struct btrfs_root *root, struct btrfs_key *min_key, path->keep_locks = keep_locks; if (ret == 0) { btrfs_unlock_up_safe(path, path->lowest_level + 1); - memcpy(min_key, &found_key, sizeof(found_key)); } return ret; }