git: 651fdc3d198d - main - Revert "vnode read(2)/write(2): acquire rangelock regardless of do_vn_io_fault()"

The branch main has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=651fdc3d198d066b18823db3b74cf38a0144dfac

commit 651fdc3d198d066b18823db3b74cf38a0144dfac
Author:     Konstantin Belousov <kib@FreeBSD.org>
AuthorDate: 2023-08-06 01:23:42 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2023-08-09 03:54:15 +0000

    Revert "vnode read(2)/write(2): acquire rangelock regardless of do_vn_io_fault()"
    
    This reverts commit 5b353925ff61b9ddb97bb453ba75278b578ed7d9.
    
    The reason is the lesser scalability of the vnode' rangelock comparing
    with the vnode lock.
    
    Requested by:   mjg
    Sponsored by:   The FreeBSD Foundation
    MFC after:      1 week
    Differential revision:  https://reviews.freebsd.org/D41334
---
 sys/kern/vfs_vnops.c | 21 +++++++--------------
 1 file changed, 7 insertions(+), 14 deletions(-)

diff --git a/sys/kern/vfs_vnops.c b/sys/kern/vfs_vnops.c
index 306840ff0357..83e95731d7c4 100644
--- a/sys/kern/vfs_vnops.c
+++ b/sys/kern/vfs_vnops.c
@@ -1443,7 +1443,6 @@ vn_io_fault(struct file *fp, struct uio *uio, struct ucred *active_cred,
 	void *rl_cookie;
 	struct vn_io_fault_args args;
 	int error;
-	bool rl_locked;
 
 	doio = uio->uio_rw == UIO_READ ? vn_read : vn_write;
 	vp = fp->f_vnode;
@@ -1466,7 +1465,12 @@ vn_io_fault(struct file *fp, struct uio *uio, struct ucred *active_cred,
 	}
 
 	foffset_lock_uio(fp, uio, flags);
-	if (vp->v_type == VREG) {
+	if (do_vn_io_fault(vp, uio)) {
+		args.kind = VN_IO_FAULT_FOP;
+		args.args.fop_args.fp = fp;
+		args.args.fop_args.doio = doio;
+		args.cred = active_cred;
+		args.flags = flags | FOF_OFFSET;
 		if (uio->uio_rw == UIO_READ) {
 			rl_cookie = vn_rangelock_rlock(vp, uio->uio_offset,
 			    uio->uio_offset + uio->uio_resid);
@@ -1478,22 +1482,11 @@ vn_io_fault(struct file *fp, struct uio *uio, struct ucred *active_cred,
 			rl_cookie = vn_rangelock_wlock(vp, uio->uio_offset,
 			    uio->uio_offset + uio->uio_resid);
 		}
-		rl_locked = true;
-	} else {
-		rl_locked = false;
-	}
-	if (do_vn_io_fault(vp, uio)) {
-		args.kind = VN_IO_FAULT_FOP;
-		args.args.fop_args.fp = fp;
-		args.args.fop_args.doio = doio;
-		args.cred = active_cred;
-		args.flags = flags | FOF_OFFSET;
 		error = vn_io_fault1(vp, uio, &args, td);
+		vn_rangelock_unlock(vp, rl_cookie);
 	} else {
 		error = doio(fp, uio, active_cred, flags | FOF_OFFSET, td);
 	}
-	if (rl_locked)
-		vn_rangelock_unlock(vp, rl_cookie);
 	foffset_unlock_uio(fp, uio, flags);
 	return (error);
 }