Add KERNEL_PANICKED macro for use in place of direct panicstr tests

vfs: only recalculate watermarks when limits are changing

Previously they would get recalculated all the time, in particular in:
getnewvnode -> vcheckspace -> vspace

vfs: deduplicate vnode allocation logic

This creates a dedicated routine (vn_alloc) to allocate vnodes.

As a side effect code duplicationw with getnewvnode_reserve is eleminated.

Add vn_free for s

vfs: deduplicate vnode allocation logic

This creates a dedicated routine (vn_alloc) to allocate vnodes.

As a side effect code duplicationw with getnewvnode_reserve is eleminated.

Add vn_free for symmetry.

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vfs: prealloc vnodes in getnewvnode_reserve

Having a reserved vnode count does not guarantee that getnewvnodes wont
block later. Said blocking partially defeats the purpose of reserving in
the first

vfs: prealloc vnodes in getnewvnode_reserve

Having a reserved vnode count does not guarantee that getnewvnodes wont
block later. Said blocking partially defeats the purpose of reserving in
the first place.

Preallocate instaed. The only consumer was always passing "1" as count
and never nesting reservations.

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vfs: incomplete pass at converting more ints to u_long

Most notably numvnodes and freevnodes were u_long, but parameters used to
govern them remained as ints.

vfs: add missing CLTFLA_MPSAFE annotations

This covers all kern/vfs_*.c files.

vfs: handle doomed vnodes in vdefer_inactive

vgone dooms the vnode while keeping VI_OWEINACT set and then drops the
interlock.

vputx can pick up the interlock and pass it to vdefer_inactive since t

vfs: handle doomed vnodes in vdefer_inactive

vgone dooms the vnode while keeping VI_OWEINACT set and then drops the
interlock.

vputx can pick up the interlock and pass it to vdefer_inactive since the
flag is set.

The race is harmless, just don't defer anything as vgone will take care of it.

Reported by: pho

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vfs: reimplement deferred inactive to use a dedicated flag (VI_DEFINACT)

The previous behavior of leaving VI_OWEINACT vnodes on the active list without
a hold count is eliminated. Hold count is kept

vfs: reimplement deferred inactive to use a dedicated flag (VI_DEFINACT)

The previous behavior of leaving VI_OWEINACT vnodes on the active list without
a hold count is eliminated. Hold count is kept and inactive processing gets
explicitly deferred by setting the VI_DEFINACT flag. The syncer is then
responsible for vdrop.

Reviewed by: kib (previous version)
Tested by: pho (in a larger patch, previous version)
Differential Revision: https://reviews.freebsd.org/D23036

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vfs: trylock in vfs_msync and refactor the func

- use LK_NOWAIT instead of calling VOP_ISLOCKED before deciding to lock
- evaluate flags before looping over vnodes

Reviewed by: kib
Tested by: pho (

vfs: trylock in vfs_msync and refactor the func

- use LK_NOWAIT instead of calling VOP_ISLOCKED before deciding to lock
- evaluate flags before looping over vnodes

Reviewed by: kib
Tested by: pho (in a larger patch, previous version)
Differential Revision: https://reviews.freebsd.org/D23035

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vfs: use a dedicated counter for free vnode recycling

Otherwise vlrureclaim activitity is mixed in and it is hard to tell which
vnodes got reclaimed.

vfs: prevent numvnodes and freevnodes re-reads when appropriate

Otherwise in code like this:
if (numvnodes > desiredvnodes)
vnlru_free_locked(numvnodes - desiredvnodes, NULL);

numvnodes can drop b

vfs: prevent numvnodes and freevnodes re-reads when appropriate

Otherwise in code like this:
if (numvnodes > desiredvnodes)
vnlru_free_locked(numvnodes - desiredvnodes, NULL);

numvnodes can drop below desiredvnodes prior to the call and if the
compiler generated another read the subtraction would get a negative
value.

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vfs: annotate numvnodes and vnode_free_list_mtx with __exclusive_cache_line

vfs: eliminate v_tag from struct vnode

There was only one consumer and it was using it incorrectly.

It is given an equivalent hack.

Reviewed by: jeff
Differential Revision: https://reviews.freebsd

vfs: eliminate v_tag from struct vnode

There was only one consumer and it was using it incorrectly.

It is given an equivalent hack.

Reviewed by: jeff
Differential Revision: https://reviews.freebsd.org/D23037

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vfs: add a helper for allocating marker vnodes

vfs: drop thread argument from vinactive

vfs: patch up vnode count assertions to report found value

vfs: drop the mostly unused flags argument from VOP_UNLOCK

Filesystems which want to use it in limited capacity can employ the
VOP_UNLOCK_FLAGS macro.

Reviewed by: kib (previous version)
Differenti

vfs: drop the mostly unused flags argument from VOP_UNLOCK

Filesystems which want to use it in limited capacity can employ the
VOP_UNLOCK_FLAGS macro.

Reviewed by: kib (previous version)
Differential Revision: https://reviews.freebsd.org/D21427

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vfs: drop an always-false check from vlrureclaim

The vnode gets held few lines prior, making the VI_FREE condition
illegal.

vfs: remove production kernel checks and mp == NULL support from vdrop

1. The only place in the tree which calls getnewvnode with mp == NULL does it
for vp_crossmp which will never execute this code

vfs: remove production kernel checks and mp == NULL support from vdrop

1. The only place in the tree which calls getnewvnode with mp == NULL does it
for vp_crossmp which will never execute this codepath. Any vnode which legally
has ->v_mount == NULL is also doomed, which once more wont execute this code.
2. Remove an assertion for v_holdcnt from production kernels. It gets taken care
of by refcount macros in debug kernels.

Any code which would want to pass NULL mp can construct a fake one instead.

Reviewed by: kib (previous version)
Differential Revision: https://reviews.freebsd.org/D22722

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vfs: flatten vop vectors

This eliminates the following loop from all VOP calls:

while(vop != NULL && \
vop->vop_spare2 == NULL && vop->vop_bypass == NULL)
vop = vop->vop_default;

Revie

vfs: flatten vop vectors

This eliminates the following loop from all VOP calls:

while(vop != NULL && \
vop->vop_spare2 == NULL && vop->vop_bypass == NULL)
vop = vop->vop_default;

Reviewed by: jeff
Tesetd by: pho
Differential Revision: https://reviews.freebsd.org/D22738

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vfs: refactor vhold and vdrop

No fuctional changes.

vfs: introduce v_irflag and make v_type smaller

The current vnode layout is not smp-friendly by having frequently read data
avoidably sharing cachelines with very frequently modified fields. In
part

vfs: introduce v_irflag and make v_type smaller

The current vnode layout is not smp-friendly by having frequently read data
avoidably sharing cachelines with very frequently modified fields. In
particular v_iflag inspected for VI_DOOMED can be found in the same line with
v_usecount. Instead make it available in the same cacheline as the v_op, v_data
and v_type which all get read all the time.

v_type is avoidably 4 bytes while the necessary data will easily fit in 1.
Shrinking it frees up 3 bytes, 2 of which get used here to introduce a new
flag field with a new value: VIRF_DOOMED.

Reviewed by: kib, jeff
Differential Revision: https://reviews.freebsd.org/D22715

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vfs: clean up vputx a little

1. replace hand-rolled macros for operation type with enum
2. unlock the vnode in vput itself, there is no need to branch on it. existence
of VPUTX_VPUT remains signific

vfs: clean up vputx a little

1. replace hand-rolled macros for operation type with enum
2. unlock the vnode in vput itself, there is no need to branch on it. existence
of VPUTX_VPUT remains significant in that the inactive variant adds LK_NOWAIT
to locking request.
3. remove the useless v_usecount assertion. few lines above the checks if
v_usecount > 0 and leaves. should the value be negative, refcount would fail.
4. the CTR return vnode %p to the freelist is incorrect as vdrop may find the
vnode with holdcnt > 1. if the like should exist, it should be moved there
5. no need to error = 0 for everyone

Reviewed by: kib, jeff (previous version)
Differential Revision: https://reviews.freebsd.org/D22718

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vfs: factor out vnode destruction out of vdrop

Sponsored by: The FreeBSD Foundation

vfs: clean up delmntque similarly to vdrop r355414