Merge ^/head r357270 through r357349.

Remove duplicated empty lines from kern/*.c

No functional changes.

Add KERNEL_PANICKED macro for use in place of direct panicstr tests

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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schedlock 4/4

Don't hold the scheduler lock while doing context switches. Instead we
unlock after selecting the new thread and switch within a spinlock
section leaving interrupts and preemption dis

schedlock 4/4

Don't hold the scheduler lock while doing context switches. Instead we
unlock after selecting the new thread and switch within a spinlock
section leaving interrupts and preemption disabled to prevent local
concurrency. This means that mi_switch() is entered with the thread
locked but returns without. This dramatically simplifies scheduler
locking because we will not hold the schedlock while spinning on
blocked lock in switch.

This change has not been made to 4BSD but in principle it would be
more straightforward.

Discussed with: markj
Reviewed by: kib
Tested by: pho
Differential Revision: https://reviews.freebsd.org/D22778

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Add kern_sync(9), and make kernel code call it instead of going
via sys_sync(2). Minor cleanup, no functional changes.

Reviewed by: kib
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Diffe

Add kern_sync(9), and make kernel code call it instead of going
via sys_sync(2). Minor cleanup, no functional changes.

Reviewed by: kib
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D19366

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Mark some more hot global variables with __read_mostly.

MFC after: 1 week

Currently the breadn_flags() and getblkx() interfaces are passed
the vnode, logical block number, and size of data block that is
being requested. They then use the VOP_BMAP function to calculate
the

Currently the breadn_flags() and getblkx() interfaces are passed
the vnode, logical block number, and size of data block that is
being requested. They then use the VOP_BMAP function to calculate
the mapping from logical block number to physical block number from
which to access the data. This change expands the interface to also
pass the physical block number in cases where the VOP_MAP function
may no longer work, for example when a file is being truncated.

No functional change.

Reviewed by: kib
Tested by: Peter Holm
Sponsored by: Netflix

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Drop the object lock in vfs_bio and cluster where it is now safe to do so.

Recent changes to busy/valid/dirty have enabled page based synchronization
and the object lock is no longer required in man

Drop the object lock in vfs_bio and cluster where it is now safe to do so.

Recent changes to busy/valid/dirty have enabled page based synchronization
and the object lock is no longer required in many cases.

Reviewed by: kib
Sponsored by: Netflix, Intel
Differential Revision: https://reviews.freebsd.org/D21597

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(4/6) Protect page valid with the busy lock.

Atomics are used for page busy and valid state when the shared busy is
held. The details of the locking protocol and valid and dirty
synchronization are

(4/6) Protect page valid with the busy lock.

Atomics are used for page busy and valid state when the shared busy is
held. The details of the locking protocol and valid and dirty
synchronization are in the updated vm_page.h comments.

Reviewed by: kib, markj
Tested by: pho
Sponsored by: Netflix, Intel
Differential Revision: https://reviews.freebsd.org/D21594

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(1/6) Replace busy checks with acquires where it is trival to do so.

This is the first in a series of patches that promotes the page busy field
to a first class lock that no longer requires the obje

(1/6) Replace busy checks with acquires where it is trival to do so.

This is the first in a series of patches that promotes the page busy field
to a first class lock that no longer requires the object lock for
consistency.

Reviewed by: kib, markj
Tested by: pho
Sponsored by: Netflix, Intel
Differential Revision: https://reviews.freebsd.org/D21548

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Merge ^/head r352764 through r353315.

Add CTLFLAG_STATS to some vfs sysctl OIDs

Add CTLFLAG_STATS to the following OIDs:

vfs.altbufferflushes
vfs.recursiveflushes
vfs.barrierwrites
vfs.flushwithdeps
vfs.reassignbufcalls

Refer to r3531

Add CTLFLAG_STATS to some vfs sysctl OIDs

Add CTLFLAG_STATS to the following OIDs:

vfs.altbufferflushes
vfs.recursiveflushes
vfs.barrierwrites
vfs.flushwithdeps
vfs.reassignbufcalls

Refer to r353111.

MFC after: 2 weeks
Sponsored by: Dell EMC Isilon

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Merge ^/head r352105 through r352307.

Use REFCOUNT_COUNT() to obtain refcount where appropriate.
Refcount waiting will set some flag bits in the refcount value.
Make sure these bits get cleared by using the REFCOUNT_COUNT()
macro to obta

Use REFCOUNT_COUNT() to obtain refcount where appropriate.
Refcount waiting will set some flag bits in the refcount value.
Make sure these bits get cleared by using the REFCOUNT_COUNT()
macro to obtain the actual refcount.

Differential Revision: https://reviews.freebsd.org/D21620
Reviewed by: kib@, markj@
MFC after: 1 week
Sponsored by: Mellanox Technologies

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buf: Add B_INVALONERR flag to discard data

Setting the B_INVALONERR flag before a synchronous write causes the buf
cache to forcibly invalidate contents if the write fails (BIO_ERROR).

This is inte

buf: Add B_INVALONERR flag to discard data

Setting the B_INVALONERR flag before a synchronous write causes the buf
cache to forcibly invalidate contents if the write fails (BIO_ERROR).

This is intended to be used to allow layers above the buffer cache to make
more informed decisions about when discarding dirty buffers without
successful write is acceptable.

As a proof of concept, use in msdosfs to handle failures to mark the on-disk
'dirty' bit during rw mount or ro->rw update.

Extending this to other filesystems is left as future work.

PR: 210316
Reviewed by: kib (with objections)
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D21539

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Use the sleepq lock rather than the page lock to protect against wakeup
races with page busy state. The object lock is still used as an interlock
to ensure that the identity stays valid. Most calle

Use the sleepq lock rather than the page lock to protect against wakeup
races with page busy state. The object lock is still used as an interlock
to ensure that the identity stays valid. Most callers should use
vm_page_sleep_if_busy() to handle the locking particulars.

Reviewed by: alc, kib, markj
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D21255

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Merge ^/head r351732 through r352104.

Remove long-dead BUF_ASSERT_{,UN}HELD assertions

These were fully neutered in r177676 (2008), but not removed at the time for
unclear reasons. They're totally dead code, so go ahead and yank them n

Remove long-dead BUF_ASSERT_{,UN}HELD assertions

These were fully neutered in r177676 (2008), but not removed at the time for
unclear reasons. They're totally dead code, so go ahead and yank them now.

No functional change.

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Merge ^/head r351317 through r351731.

Avoid direct accesses of the vm_page wire_count field.

No functional change intended.

Sponsored by: Netflix

MFHead @350453

Sponsored by: The FreeBSD Foundation

Centralize the logic in vfs_vmio_unwire() and sendfile_free_page().

Both of these functions atomically unwire a page, optionally attempt
to free the page, and enqueue or requeue the page. Add funct

Centralize the logic in vfs_vmio_unwire() and sendfile_free_page().

Both of these functions atomically unwire a page, optionally attempt
to free the page, and enqueue or requeue the page. Add functions
vm_page_release() and vm_page_release_locked() to perform the same task.
The latter must be called with the page's object lock held.

As a side effect of this refactoring, the buffer cache will no longer
attempt to free mapped pages when completing direct I/O. This is
consistent with the handling of pages by sendfile(SF_NOCACHE).

Reviewed by: alc, kib
MFC after: 2 weeks
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D20986

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MFHead @348740

Sponsored by: The FreeBSD Foundation

Include ktr.h in more compilation units

Similar to r348026, exhaustive search for uses of CTRn() and cross reference
ktr.h includes. Where it was obvious that an OS compat header of some kind
inclu

Include ktr.h in more compilation units

Similar to r348026, exhaustive search for uses of CTRn() and cross reference
ktr.h includes. Where it was obvious that an OS compat header of some kind
included ktr.h indirectly, .c files were left alone. Some of these files
clearly got ktr.h via header pollution in some scenarios, or tinderbox would
not be passing prior to this revision, but go ahead and explicitly include it
in files using it anyway.

Like r348026, these CUs did not show up in tinderbox as missing the include.

Reported by: peterj (arm64/mp_machdep.c)
X-MFC-With: r347984
Sponsored by: Dell EMC Isilon

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