Re: mention vdrop in vhold.9
On Sat, Sep 15, 2012 at 07:26:40PM -0700, Philip Guenther wrote: On Sat, Sep 15, 2012 at 1:42 AM, Jason McIntyre j...@kerhand.co.uk wrote: On Sat, Sep 15, 2012 at 10:19:35AM +0200, Michal Mazurek wrote: doesn;t the code mean the check is for zero, not less than or equal to zero? Oops, you're right. everything else looks alright. i'll commit it soon if no one objects, though i'd prefer it if another developer would ok it. I don't think we, in general, promise to panic. Note that it won't if you compile without the DIAGNOSTIC option. i think its fine since default is DIAGNOSTIC, but i'm fine with removing that bit. As for the rest of the wording, I think it would be better if it mirrored the wording of the vhold() description, say: The vdrop() function decrements the v_holdcnt of the given vnode. If the vnode is on the vnode hold list and its v_holdcnt and v_usecount are both zero, it will be removed from the vnode hold list and added to the free list. vhold() and vdrop() really are mirrors of each other like that... Philip thanks, i think that reads better too. ok? jmc Index: Makefile === RCS file: /cvs/src/share/man/man9/Makefile,v retrieving revision 1.171 diff -u -r1.171 Makefile --- Makefile21 Jun 2012 18:02:21 - 1.171 +++ Makefile16 Sep 2012 09:53:04 - @@ -373,5 +373,6 @@ MLINKS+=workq_add_task.9 workq_create.9 \ workq_add_task.9 workq_queue_task.9 \ workq_add_task.9 workq_destroy.9 +MLINKS+=vhold.9 vdrop.9 .include bsd.prog.mk Index: vhold.9 === RCS file: /cvs/src/share/man/man9/vhold.9,v retrieving revision 1.6 diff -u -r1.6 vhold.9 --- vhold.9 15 Dec 2009 07:34:58 - 1.6 +++ vhold.9 16 Sep 2012 09:53:04 - @@ -31,13 +31,16 @@ .Dt VHOLD 9 .Os .Sh NAME -.Nm vhold +.Nm vhold , +.Nm vdrop .Nd acquire a hold on a vnode .Sh SYNOPSIS .Fd #include sys/param.h .Fd #include sys/vnode.h .Ft void .Fn vhold struct vnode *vp +.Ft void +.Fn vdrop struct vnode *vp .Sh DESCRIPTION The .Fn vhold @@ -50,6 +53,18 @@ .Va v_usecount are both zero, it will be removed from the free list and added to the vnode hold list. +.Pp +The +.Fn vdrop +function decrements the +.Va v_holdcnt +of the given vnode. +If the vnode is on the vnode hold list and its +.Va v_holdcnt +and +.Va v_usecount +are both zero, it will be removed from the vnode hold list and +added to the freed list. .Sh SEE ALSO .Xr vnode 9 .Sh AUTHORS
Re: mention vdrop in vhold.9
On Sun, Sep 16, 2012 at 10:54:40AM +0059, Jason McIntyre wrote: thanks, i think that reads better too. ok? jmc just spotted that the name description (Nd) for this file is now out of date. updated accordingly (from freebsd). ok? jmc Index: Makefile === RCS file: /cvs/src/share/man/man9/Makefile,v retrieving revision 1.171 diff -u -r1.171 Makefile --- Makefile21 Jun 2012 18:02:21 - 1.171 +++ Makefile16 Sep 2012 16:17:05 - @@ -373,5 +373,6 @@ MLINKS+=workq_add_task.9 workq_create.9 \ workq_add_task.9 workq_queue_task.9 \ workq_add_task.9 workq_destroy.9 +MLINKS+=vhold.9 vdrop.9 .include bsd.prog.mk Index: vhold.9 === RCS file: /cvs/src/share/man/man9/vhold.9,v retrieving revision 1.6 diff -u -r1.6 vhold.9 --- vhold.9 15 Dec 2009 07:34:58 - 1.6 +++ vhold.9 16 Sep 2012 16:17:05 - @@ -31,13 +31,16 @@ .Dt VHOLD 9 .Os .Sh NAME -.Nm vhold -.Nd acquire a hold on a vnode +.Nm vhold , +.Nm vdrop +.Nd acquire/release a hold on a vnode .Sh SYNOPSIS .Fd #include sys/param.h .Fd #include sys/vnode.h .Ft void .Fn vhold struct vnode *vp +.Ft void +.Fn vdrop struct vnode *vp .Sh DESCRIPTION The .Fn vhold @@ -50,6 +53,18 @@ .Va v_usecount are both zero, it will be removed from the free list and added to the vnode hold list. +.Pp +The +.Fn vdrop +function decrements the +.Va v_holdcnt +of the given vnode. +If the vnode is on the vnode hold list and its +.Va v_holdcnt +and +.Va v_usecount +are both zero, it will be removed from the vnode hold list and +added to the freed list. .Sh SEE ALSO .Xr vnode 9 .Sh AUTHORS
Re: mention vdrop in vhold.9
On Sun, Sep 16, 2012 at 9:18 AM, Jason McIntyre j...@kerhand.co.uk wrote: just spotted that the name description (Nd) for this file is now out of date. updated accordingly (from freebsd). ok? Ship it! guenther@
Re: mention vdrop in vhold.9
On Fri, Sep 14, 2012 at 08:08:48PM +0200, Michal Mazurek wrote: Taken from FreeBSD. an altered version of your diff was committed. thanks for the mail, jmc
Re: mention vdrop in vhold.9
On Fri, Sep 14, 2012 at 08:08:48PM +0200, Michal Mazurek wrote:
Taken from FreeBSD.
Index: Makefile
===
RCS file: /cvs/src/share/man/man9/Makefile,v
retrieving revision 1.171
diff -u -p -r1.171 Makefile
--- Makefile 21 Jun 2012 18:02:21 - 1.171
+++ Makefile 14 Sep 2012 18:06:46 -
@@ -373,5 +373,6 @@ MLINKS+=VOP_LOOKUP.9 VOP_ABORTOP.9 VOP_L
MLINKS+=workq_add_task.9 workq_create.9 \
workq_add_task.9 workq_queue_task.9 \
workq_add_task.9 workq_destroy.9
+MLINKS+=vhold.9 vdrop.9
.include bsd.prog.mk
Index: vhold.9
===
RCS file: /cvs/src/share/man/man9/vhold.9,v
retrieving revision 1.6
diff -u -p -r1.6 vhold.9
--- vhold.9 15 Dec 2009 07:34:58 - 1.6
+++ vhold.9 14 Sep 2012 18:06:46 -
@@ -38,6 +38,8 @@
.Fd #include sys/vnode.h
.Ft void
.Fn vhold struct vnode *vp
+.Ft void
+.Fn vdrop struct vnode *vp
.Sh DESCRIPTION
The
.Fn vhold
@@ -50,6 +52,16 @@ and
.Va v_usecount
are both zero, it will be removed from the free list and
added to the vnode hold list.
+.Pp
+The
+.Fn vdrop
+function decrements the
+.Va v_holdcnt
+of the vnode.
+If the holdcount is less than or equal to zero prior to calling
+.Fn vdrop ,
+the system will panic.
+If the vnode is no longer referenced, it will be freed.
.Sh SEE ALSO
.Xr vnode 9
.Sh AUTHORS
in vfs_subr.c (bear with me ;) it has:
/* Lose interest in a vnode. */
void
vdrop(struct vnode *vp)
{
#ifdef DIAGNOSTIC
if (vp-v_holdcnt == 0)
panic(vdrop: zero holdcnt);
#endif
vp-v_holdcnt--;
the text pasted is:
If the holdcount is less than or equal to zero
prior to calling vdrop...
doesn;t the code mean the check is for zero, not less than or equal to
zero?
jmc
Re: mention vdrop in vhold.9
On Sat, Sep 15, 2012 at 08:44:17AM +0100, Jason McIntyre wrote:
in vfs_subr.c (bear with me ;) it has:
/* Lose interest in a vnode. */
void
vdrop(struct vnode *vp)
{
#ifdef DIAGNOSTIC
if (vp-v_holdcnt == 0)
panic(vdrop: zero holdcnt);
#endif
vp-v_holdcnt--;
the text pasted is:
If the holdcount is less than or equal to zero
prior to calling vdrop...
doesn;t the code mean the check is for zero, not less than or equal to
zero?
Oops, you're right.
Index: Makefile
===
RCS file: /cvs/src/share/man/man9/Makefile,v
retrieving revision 1.171
diff -u -p -r1.171 Makefile
--- Makefile21 Jun 2012 18:02:21 - 1.171
+++ Makefile14 Sep 2012 18:06:46 -
@@ -373,5 +373,6 @@ MLINKS+=VOP_LOOKUP.9 VOP_ABORTOP.9 VOP_L
MLINKS+=workq_add_task.9 workq_create.9 \
workq_add_task.9 workq_queue_task.9 \
workq_add_task.9 workq_destroy.9
+MLINKS+=vhold.9 vdrop.9
.include bsd.prog.mk
Index: vhold.9
===
RCS file: /cvs/src/share/man/man9/vhold.9,v
retrieving revision 1.6
diff -u -p -r1.6 vhold.9
--- vhold.9 15 Dec 2009 07:34:58 - 1.6
+++ vhold.9 14 Sep 2012 18:06:46 -
@@ -38,6 +38,8 @@
.Fd #include sys/vnode.h
.Ft void
.Fn vhold struct vnode *vp
+.Ft void
+.Fn vdrop struct vnode *vp
.Sh DESCRIPTION
The
.Fn vhold
@@ -50,6 +52,16 @@ and
.Va v_usecount
are both zero, it will be removed from the free list and
added to the vnode hold list.
+.Pp
+The
+.Fn vdrop
+function decrements the
+.Va v_holdcnt
+of the vnode.
+If the holdcount is zero prior to calling
+.Fn vdrop ,
+the system will panic.
+If the vnode is no longer referenced, it will be freed.
.Sh SEE ALSO
.Xr vnode 9
.Sh AUTHORS
--
Michal Mazurek
Re: mention vdrop in vhold.9
On Sat, Sep 15, 2012 at 10:19:35AM +0200, Michal Mazurek wrote: doesn;t the code mean the check is for zero, not less than or equal to zero? Oops, you're right. everything else looks alright. i'll commit it soon if no one objects, though i'd prefer it if another developer would ok it. jmc Index: Makefile === RCS file: /cvs/src/share/man/man9/Makefile,v retrieving revision 1.171 diff -u -p -r1.171 Makefile --- Makefile 21 Jun 2012 18:02:21 - 1.171 +++ Makefile 14 Sep 2012 18:06:46 - @@ -373,5 +373,6 @@ MLINKS+=VOP_LOOKUP.9 VOP_ABORTOP.9 VOP_L MLINKS+=workq_add_task.9 workq_create.9 \ workq_add_task.9 workq_queue_task.9 \ workq_add_task.9 workq_destroy.9 +MLINKS+=vhold.9 vdrop.9 .include bsd.prog.mk Index: vhold.9 === RCS file: /cvs/src/share/man/man9/vhold.9,v retrieving revision 1.6 diff -u -p -r1.6 vhold.9 --- vhold.9 15 Dec 2009 07:34:58 - 1.6 +++ vhold.9 14 Sep 2012 18:06:46 - @@ -38,6 +38,8 @@ .Fd #include sys/vnode.h .Ft void .Fn vhold struct vnode *vp +.Ft void +.Fn vdrop struct vnode *vp .Sh DESCRIPTION The .Fn vhold @@ -50,6 +52,16 @@ and .Va v_usecount are both zero, it will be removed from the free list and added to the vnode hold list. +.Pp +The +.Fn vdrop +function decrements the +.Va v_holdcnt +of the vnode. +If the holdcount is zero prior to calling +.Fn vdrop , +the system will panic. +If the vnode is no longer referenced, it will be freed. .Sh SEE ALSO .Xr vnode 9 .Sh AUTHORS -- Michal Mazurek
Re: mention vdrop in vhold.9
On Sat, Sep 15, 2012 at 1:42 AM, Jason McIntyre j...@kerhand.co.uk wrote: On Sat, Sep 15, 2012 at 10:19:35AM +0200, Michal Mazurek wrote: doesn;t the code mean the check is for zero, not less than or equal to zero? Oops, you're right. everything else looks alright. i'll commit it soon if no one objects, though i'd prefer it if another developer would ok it. I don't think we, in general, promise to panic. Note that it won't if you compile without the DIAGNOSTIC option. As for the rest of the wording, I think it would be better if it mirrored the wording of the vhold() description, say: The vdrop() function decrements the v_holdcnt of the given vnode. If the vnode is on the vnode hold list and its v_holdcnt and v_usecount are both zero, it will be removed from the vnode hold list and added to the free list. vhold() and vdrop() really are mirrors of each other like that... Philip
mention vdrop in vhold.9
Taken from FreeBSD. Index: Makefile === RCS file: /cvs/src/share/man/man9/Makefile,v retrieving revision 1.171 diff -u -p -r1.171 Makefile --- Makefile21 Jun 2012 18:02:21 - 1.171 +++ Makefile14 Sep 2012 18:06:46 - @@ -373,5 +373,6 @@ MLINKS+=VOP_LOOKUP.9 VOP_ABORTOP.9 VOP_L MLINKS+=workq_add_task.9 workq_create.9 \ workq_add_task.9 workq_queue_task.9 \ workq_add_task.9 workq_destroy.9 +MLINKS+=vhold.9 vdrop.9 .include bsd.prog.mk Index: vhold.9 === RCS file: /cvs/src/share/man/man9/vhold.9,v retrieving revision 1.6 diff -u -p -r1.6 vhold.9 --- vhold.9 15 Dec 2009 07:34:58 - 1.6 +++ vhold.9 14 Sep 2012 18:06:46 - @@ -38,6 +38,8 @@ .Fd #include sys/vnode.h .Ft void .Fn vhold struct vnode *vp +.Ft void +.Fn vdrop struct vnode *vp .Sh DESCRIPTION The .Fn vhold @@ -50,6 +52,16 @@ and .Va v_usecount are both zero, it will be removed from the free list and added to the vnode hold list. +.Pp +The +.Fn vdrop +function decrements the +.Va v_holdcnt +of the vnode. +If the holdcount is less than or equal to zero prior to calling +.Fn vdrop , +the system will panic. +If the vnode is no longer referenced, it will be freed. .Sh SEE ALSO .Xr vnode 9 .Sh AUTHORS -- Michal Mazurek
