git: 4deb934c1a10 - main - vfs: Simplify vfs_write_resume()/vn_start_write_refed()

The branch main has been updated by olce:

URL: https://cgit.FreeBSD.org/src/commit/?id=4deb934c1a1051d7ef41e9309d066742722ce180

commit 4deb934c1a1051d7ef41e9309d066742722ce180
Author:     Olivier Certner <olce@FreeBSD.org>
AuthorDate: 2026-03-27 12:43:24 +0000
Commit:     Olivier Certner <olce@FreeBSD.org>
CommitDate: 2026-03-30 09:24:23 +0000

    vfs: Simplify vfs_write_resume()/vn_start_write_refed()
    
    The call to vn_start_write_refed() from vfs_write_resume() with
    'mplocked' set to 'true' exactly boils down to doing an increment of
    'mnt_writeopcount', albeit with lots of unnecessary verifications.
    
    Replace it with an inline incrementation.  As the original call was the
    last with 'mplocked' with 'true', remove the 'mplocked' parameter from
    vfs_write_resume(), simplifying its code accordingly ('mplocked' always
    false).
    
    While here, in vfs_write_resume(), initialize 'error' out of the mount
    lock.
    
    Reviewed by:    kib
    MFC after:      1 week
    Sponsored by:   The FreeBSD Foundation
    Differential Revision:  https://reviews.freebsd.org/D56108
---
 sys/kern/vfs_vnops.c | 22 ++++++++++------------
 1 file changed, 10 insertions(+), 12 deletions(-)

diff --git a/sys/kern/vfs_vnops.c b/sys/kern/vfs_vnops.c
index ea8f8437b743..4061b2272193 100644
--- a/sys/kern/vfs_vnops.c
+++ b/sys/kern/vfs_vnops.c
@@ -2078,26 +2078,22 @@ vn_closefile(struct file *fp, struct thread *td)
  * suspension is over, and then proceed.
  */
 static int
-vn_start_write_refed(struct mount *mp, int flags, bool mplocked)
+vn_start_write_refed(struct mount *mp, int flags)
 {
 	struct mount_pcpu *mpcpu;
 	int error, mflags;
 
-	if (__predict_true(!mplocked) && (flags & V_XSLEEP) == 0 &&
-	    vfs_op_thread_enter(mp, mpcpu)) {
+	if ((flags & V_XSLEEP) == 0 && vfs_op_thread_enter(mp, mpcpu)) {
 		MPASS((mp->mnt_kern_flag & MNTK_SUSPEND) == 0);
 		vfs_mp_count_add_pcpu(mpcpu, writeopcount, 1);
 		vfs_op_thread_exit(mp, mpcpu);
 		return (0);
 	}
 
-	if (mplocked)
-		mtx_assert(MNT_MTX(mp), MA_OWNED);
-	else
-		MNT_ILOCK(mp);
-
 	error = 0;
 
+	MNT_ILOCK(mp);
+
 	/*
 	 * Check on status of suspension.
 	 */
@@ -2165,7 +2161,7 @@ vn_start_write(struct vnode *vp, struct mount **mpp, int flags)
 	if (vp == NULL)
 		vfs_ref(mp);
 
-	error = vn_start_write_refed(mp, flags, false);
+	error = vn_start_write_refed(mp, flags);
 	if (error != 0 && (flags & V_NOWAIT) == 0)
 		*mpp = NULL;
 	return (error);
@@ -2373,10 +2369,12 @@ vfs_write_resume(struct mount *mp, int flags)
 		if ((flags & VR_NO_SUSPCLR) == 0)
 			VFS_SUSP_CLEAN(mp);
 		vfs_op_exit(mp);
-	} else if ((flags & VR_START_WRITE) != 0) {
-		MNT_REF(mp);
-		vn_start_write_refed(mp, 0, true);
 	} else {
+		if ((flags & VR_START_WRITE) != 0) {
+			MNT_REF(mp);
+			mp->mnt_writeopcount++;
+		}
+
 		MNT_IUNLOCK(mp);
 	}
 }