From patchwork Fri Mar 28 16:15:53 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Brauner X-Patchwork-Id: 14032228 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 85C551DD0E7; Fri, 28 Mar 2025 16:16:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743178579; cv=none; b=iL/I6M/lthvJryKc9ZNpSUv2FKwqHUCKmRhAf6DRvC/H9UCJ8obbB+syVkPAijWOtyjHlKxebrP5BfVRdWLI0NrkRTAAmQ+AWku/jbXYsMbUWDQmIPfJuWevzXRVtm1z0iPMymzX2srvdtMV/GyvyylTecn7vbabw8QT4Kb3LNc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743178579; c=relaxed/simple; bh=tXNgHPkpI1RYcg6+uolFMirXAFbH/6dKuJTHpZX5Tj8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=C5P4NIeb9YbL9Qi/GCN7Mb9vxfSQoTynPHuCS8j0Dj6vH8HbaPO8pxIcnmYBV1BkJ5fGrk2U7jPzBNfWbqdNPeJm3SHlYKrUKYm/ufeCg3/WlVyHo9C7tLJMtaC77FScWX8EI1qvUMJdJT0Fk0xH2OvyvGDtOaSKk2DNDh+CJGE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=EyhuXGf2; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="EyhuXGf2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DE676C4CEE5; Fri, 28 Mar 2025 16:16:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1743178578; bh=tXNgHPkpI1RYcg6+uolFMirXAFbH/6dKuJTHpZX5Tj8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EyhuXGf281TnYATQKatubpErzYkG1h+BNwDsUshE4fPss+QazVEBqi2jufIopsnwj ZcstGZ20IjlCt0ski02ckI3ZnkYTvE+NBhNTF73N6wimaU3fHUIZkmMRKvhOm8VKJL PapxbW+5scJo5si76/dM5PSJg8ZceQfVJJ7LdzmyPL7G/UW0SRWX+TZsja3PigKbrm Eg/mAJUhAHeKwYvtScxCGed3GJJGJC9eyj71h63c1nSBKROZFYIpvGL/9TYsE2jT/0 vSlpOKQlZsycslyhn2pYZirTHp7+GgDsmgXf7i39BE/ZC6OA9A2cB+ZvLBjr9jOIrc gBlPHHT7bOS7g== From: Christian Brauner To: linux-fsdevel@vger.kernel.org, jack@suse.cz Cc: Christian Brauner , linux-kernel@vger.kernel.org, James Bottomley , mcgrof@kernel.org, hch@infradead.org, david@fromorbit.com, rafael@kernel.org, djwong@kernel.org, pavel@kernel.org, peterz@infradead.org, mingo@redhat.com, will@kernel.org, boqun.feng@gmail.com Subject: [PATCH 1/6] super: remove pointless s_root checks Date: Fri, 28 Mar 2025 17:15:53 +0100 Message-ID: <20250328-work-freeze-v1-1-a2c3a6b0e7a6@kernel.org> X-Mailer: git-send-email 2.47.2 In-Reply-To: <20250328-work-freeze-v1-0-a2c3a6b0e7a6@kernel.org> References: <20250328-work-freeze-v1-0-a2c3a6b0e7a6@kernel.org> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Mailer: b4 0.15-dev-42535 X-Developer-Signature: v=1; a=openpgp-sha256; l=1525; i=brauner@kernel.org; h=from:subject:message-id; bh=tXNgHPkpI1RYcg6+uolFMirXAFbH/6dKuJTHpZX5Tj8=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMaQ/O+1od56r/YvzzdI/Ep2qs91n3hEM0jgc9Oi+wCnT1 bN81yfndpSyMIhxMciKKbI4tJuEyy3nqdhslKkBM4eVCWQIAxenAEzEcj3DL+bH72Y/nPdru6jP 8S7JGc91xFX9Kjstj9Tejitd7WSoU87wV4bL/YLBiecHHiR+5pjEX744mnXyRI9Thcfv9VVPZ2h 6zQAA X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 The locking guarantees that the superblock is alive and sb->s_root is still set. Remove the pointless check. Signed-off-by: Christian Brauner --- fs/super.c | 19 ++++++------------- 1 file changed, 6 insertions(+), 13 deletions(-) diff --git a/fs/super.c b/fs/super.c index 97a17f9d9023..dc14f4bf73a6 100644 --- a/fs/super.c +++ b/fs/super.c @@ -930,8 +930,7 @@ void iterate_supers(void (*f)(struct super_block *, void *), void *arg) locked = super_lock_shared(sb); if (locked) { - if (sb->s_root) - f(sb, arg); + f(sb, arg); super_unlock_shared(sb); } @@ -967,11 +966,8 @@ void iterate_supers_type(struct file_system_type *type, spin_unlock(&sb_lock); locked = super_lock_shared(sb); - if (locked) { - if (sb->s_root) - f(sb, arg); - super_unlock_shared(sb); - } + if (locked) + f(sb, arg); spin_lock(&sb_lock); if (p) @@ -991,18 +987,15 @@ struct super_block *user_get_super(dev_t dev, bool excl) spin_lock(&sb_lock); list_for_each_entry(sb, &super_blocks, s_list) { - if (sb->s_dev == dev) { + if (sb->s_dev == dev) { bool locked; sb->s_count++; spin_unlock(&sb_lock); /* still alive? */ locked = super_lock(sb, excl); - if (locked) { - if (sb->s_root) - return sb; - super_unlock(sb, excl); - } + if (locked) + return sb; /* caller will drop */ /* nope, got unmounted */ spin_lock(&sb_lock); __put_super(sb);