Merge ^/head r357270 through r357349.

Remove duplicated empty lines from kern/*.c

No functional changes.

procdesc: allow to collect status through wait(1) if process is traced

The debugger like truss(1) depends on the wait(2) syscall. This syscall
waits for ALL children. When it is waiting for ALL chil

procdesc: allow to collect status through wait(1) if process is traced

The debugger like truss(1) depends on the wait(2) syscall. This syscall
waits for ALL children. When it is waiting for ALL child's the children
created by process descriptors are not returned. This behavior was
introduced because we want to implement libraries which may pdfork(1).

The behavior of process descriptor brakes truss(1) because it will
not be able to collect the status of processes with process descriptors.

To address this problem the status is returned to parent when the
child is traced. While the process is traced the debugger is the new parent.
In case the original parent and debugger are the same process it means the
debugger explicitly used pdfork() to create the child. In that case the debugger
should be using kqueue()/pdwait() instead of wait().

Add test case to verify that. The test case was implemented by markj@.

Reviewed by: kib, markj
Discussed with: jhb
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D20362

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Merge ^/head r351317 through r351731.

proc: clear pid bitmap entry after dropping proctree lock

There is no correctness change here, but the procid lock is contended in
the fork path and taking it while holding proctree avoidably extend

proc: clear pid bitmap entry after dropping proctree lock

There is no correctness change here, but the procid lock is contended in
the fork path and taking it while holding proctree avoidably extends its
hold time.

Note that there are other ids which can end up getting cleared with the
lock.

Sponsored by: The FreeBSD Foundation

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proc: eliminate the zombproc list

It is not needed by anything in the kernel and it slightly drives up contention
on both proctree and allproc locks.

Reviewed by: kib
Sponsored by: The FreeBSD Foun

proc: eliminate the zombproc list

It is not needed by anything in the kernel and it slightly drives up contention
on both proctree and allproc locks.

Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21447

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exit1: fix style nits

MFC after: 1 month

proc: introduce the proc_add_orphan function

This API allows adding the process to its parent orphan list.

Reviewed by: kib, markj
MFC after: 1 month

exit1: postpone clearing P_TRACED flag until the proctree lock is acquired

In case of the process being debugged. The P_TRACED is cleared very early,
which would make procdesc_close() not calling pr

exit1: postpone clearing P_TRACED flag until the proctree lock is acquired

In case of the process being debugged. The P_TRACED is cleared very early,
which would make procdesc_close() not calling proc_clear_orphan().
That would result in the debugged process can not be able to collect
status of the process with process descriptor.

Reviewed by: markj, kib
Tested by: pho
MFC after: 1 month

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MFHead @350453

Sponsored by: The FreeBSD Foundation

proc: make clear_orphan an public API

This will be useful for other patches with process descriptors.
Change its name as well.

Reviewed by: markj, kib

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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Extract eventfilter declarations to sys/_eventfilter.h

This allows replacing "sys/eventfilter.h" includes with "sys/_eventfilter.h"
in other header files (e.g., sys/{bus,conf,cpu}.h) and reduces hea

Extract eventfilter declarations to sys/_eventfilter.h

This allows replacing "sys/eventfilter.h" includes with "sys/_eventfilter.h"
in other header files (e.g., sys/{bus,conf,cpu}.h) and reduces header
pollution substantially.

EVENTHANDLER_DECLARE and EVENTHANDLER_LIST_DECLAREs were moved out of .c
files into appropriate headers (e.g., sys/proc.h, powernv/opal.h).

As a side effect of reduced header pollution, many .c files and headers no
longer contain needed definitions. The remainder of the patch addresses
adding appropriate includes to fix those files.

LOCK_DEBUG and LOCK_FILE_LINE_ARG are moved to sys/_lock.h, as required by
sys/mutex.h since r326106 (but silently protected by header pollution prior
to this change).

No functional change (intended). Of course, any out of tree modules that
relied on header pollution for sys/eventhandler.h, sys/lock.h, or
sys/mutex.h inclusion need to be fixed. __FreeBSD_version has been bumped.

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MFHead @347527

Sponsored by: The FreeBSD Foundation

Set the p_oppid field of orphans when exiting.

Such processes will be reparented to the reaper when the current
parent is done with them (i.e., ptrace detached), so p_oppid must be
updated according

Set the p_oppid field of orphans when exiting.

Such processes will be reparented to the reaper when the current
parent is done with them (i.e., ptrace detached), so p_oppid must be
updated accordingly.

Add a regression test to exercise this code path. Previously it
would not be possible to reap an orphan with a stale oppid.

Reviewed by: kib, mjg
Tested by: pho
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D19825

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Merge ^/head r340918 through r341763.

proc: handle sdt exit probe before taking the proc lock

Sponsored by: The FreeBSD Foundation

proc: when exiting move to zombproc before taking proctree

The kernel was already doing this prior to r329615. It was changed
to reduce contention on allproc. However, introduction of pidhash
locks

proc: when exiting move to zombproc before taking proctree

The kernel was already doing this prior to r329615. It was changed
to reduce contention on allproc. However, introduction of pidhash
locks and removal of proctree -> allproc ordering from fork thanks
to bitmaps fixed things enough to make this change pessimal.

waitpid takes proctree on each call and this change (now) causes
avoidable stalls if allproc is held.

Sponsored by: The FreeBSD Foundation

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Manage process-related IDs with bitmaps

Currently unique pid allocation on fork often requires a full walk of
process, group, session lists to make sure it is not used by anything.
This has a side e

Manage process-related IDs with bitmaps

Currently unique pid allocation on fork often requires a full walk of
process, group, session lists to make sure it is not used by anything.
This has a side effect of requiring proctree to be held along with allproc,
which adds more contention in poudriere -j 128.

The patch below implements trivial bitmaps which gets rid of the problem.
Dedicated lock is introduced to manage IDs.

While here a bug was discovered: all processes would inherit reap id from
the first process spawned by init. This had a side effect of keeping the
ID used and when allocation rolls over to the beginning it keeps being
skipped.

The patch is loosely based on initial work by mjoras@.

Reviewed by: kib
Sponsored by: The FreeBSD Foundation

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proc: create a dedicated lock for zombproc to ligthen the load on allproc_lock

waitpid always takes proctree to evaluate the list, but only takes allproc
if it can reap. With this patch allproc is n

proc: create a dedicated lock for zombproc to ligthen the load on allproc_lock

waitpid always takes proctree to evaluate the list, but only takes allproc
if it can reap. With this patch allproc is no longer taken, which helps during
poudriere -j 128.

Discussed with: kib
Sponsored by: The FreeBSD Foundation

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Merge ^/head r340427 through r340868.

Revert "fork: fix use-after-free with vfork"

This unreliably breaks libc handling of vfork where forking succeded,
but execve did not.

vfork code in libc performs waitpid with WNOHANG in case of fa

Revert "fork: fix use-after-free with vfork"

This unreliably breaks libc handling of vfork where forking succeded,
but execve did not.

vfork code in libc performs waitpid with WNOHANG in case of failed exec.
With the fix exit codepath was waking up the parent before the child
fully transitioned to a zombie. Woken up parent would waitpid, which
could find a not-yet-zombie child and fail to reap it due to the WNOHANG
flag.

While removing the flag fixes the problem, it is not an option due to older
releases which would still suffer from the kernel change.

Revert the fix until a solution can be worked out.

Note that while use-after-free which gets back due to the revert is a real
bug, it's side-effects are limited due to the fact that struct proc memory
is never released by UMA.

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fork: fix use-after-free with vfork

The pointer to the child is stored without any reference held. Then it is
blindly used to wait until P_PPWAIT is cleared. However, if the child is
autoreaped it c

fork: fix use-after-free with vfork

The pointer to the child is stored without any reference held. Then it is
blindly used to wait until P_PPWAIT is cleared. However, if the child is
autoreaped it could have exited and get freed before the parent started
waiting.

Use the existing hold mechanism to mitigate the problem. Most common case
of doing exec remains unchanged. The corner case of doing exit performs
wake up before waiting for holds to clear.

Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D18295

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proc: update list manipulation comment on process exit

Processes stay in the hash until they get reaped.

This code does not unlink the child from the parent, so remove
the claim that it does.

Spon

proc: update list manipulation comment on process exit

Processes stay in the hash until they get reaped.

This code does not unlink the child from the parent, so remove
the claim that it does.

Sponsored by: The FreeBSD Foundation

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