Add bit_ffs_area_at and bit_ffc_area_at functions for searching a bit
string for a sequence of contiguous set or unset bits of at least the
specified size.
The bit_ffc_area function will be used by the Intel ice driver for
implementing resource assignment logic using a bitstring to represent
whether or not a given index has been assigned or is currently free.
The bit_ffs_area, bit_ffc_area_at and bit_ffs_area_at functions are
implemented for completeness.
I'd like to add further test cases for the new functions, but I'm not
really sure how to add them easily. The new functions depend on specific
sequences of bits being set, while the bitstring tests appear to run for
varying bit sizes.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Submitted by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed by: asomers@, erj@
MFC after: 1 week
Sponsored by: Intel Corporation
Differential Revision: https://reviews.freebsd.org/D22400
This provides a framework to define a template describing
a set of "variables of interest" and the intended way for
the framework to maintain them (for example the maximum, sum,
t-digest, or a combination thereof). Afterwards the user
code feeds in the raw data, and the framework maintains
these variables inside a user-provided, opaque stats blobs.
The framework also provides a way to selectively extract the
stats from the blobs. The stats(3) framework can be used in
both userspace and the kernel.
See the stats(3) manual page for details.
This will be used by the upcoming TCP statistics gathering code,
https://reviews.freebsd.org/D20655.
The stats(3) framework is disabled by default for now, except
in the NOTES kernel (for QA); it is expected to be enabled
in amd64 GENERIC after a cool down period.
Reviewed by: sef (earlier version)
Obtained from: Netflix
Relnotes: yes
Sponsored by: Klara Inc, Netflix
Differential Revision: https://reviews.freebsd.org/D20477
and reinserting it back with an updated key.
This is one of dependencies for the upcoming stats(3) code.
Reviewed by: cem
Obtained from: Netflix
MFC after: 2 weeks
Sponsored by: Klara Inc, Netflix
Differential Revision: https://reviews.freebsd.org/D21786
to the traditional tree(3) RB trees, but using an array (preallocated,
linear chunk of memory) to store the tree.
This avoids allocation overhead, improves memory locality,
and makes it trivially easy to share/transfer/copy the entire tree
without the need for marshalling. The downside is that the size
is fixed at initialization time; there is no mechanism to resize
it.
This is one of the dependencies for the new stats(3) framework
(https://reviews.freebsd.org/D20477).
Reviewed by: bcr (man pages), markj
Discussed with: cem
MFC after: 2 weeks
Sponsored by: Klara Inc, Netflix
Obtained from: Netflix
Differential Revision: https://reviews.freebsd.org/D20324
This makes it possible to perform mathematical operations on
fractional values without using floating point. It operates on Q
numbers, which are integer-sized, opaque structures initialized
to hold a chosen number of integer and fractional bits.
For a general description of the Q number system, see the "Fixed Point
Representation & Fractional Math" whitepaper[1]; for the actual
API see the qmath(3) man page.
This is one of dependencies for the upcoming stats(3) framework[2]
that will be applied to the TCP stack in a later commit.
1. https://www.superkits.net/whitepapers/Fixed%20Point%20Representation%20&%20Fractional%20Math.pdf
2. https://reviews.freebsd.org/D20477
Reviewed by: bcr (man pages, earlier version), sef (earlier version)
Discussed with: cem, dteske, imp, lstewart
Sponsored By: Klara Inc, Netflix
Obtained from: Netflix
Differential Revision: https://reviews.freebsd.org/D20116
We don't split the other man pages in their own package so do the same for runtime.
Reviewed by: bapt, gjb
Differential Revision: https://reviews.freebsd.org/D20962
The description of CMSG_FIRSTHDR used two variables (mhdr and msg) to
reference the same thing. Use msghdr consistency across the manual page
instead.
Reviewed by: bcr
Approved by: krion (mentor, implicit), mat (mentor, implicit)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D17804
This basically adds makes use of the C99 restrict keyword, and also
adds some 'const's to four threading functions: pthread_mutexattr_gettype(),
pthread_mutexattr_getprioceiling(), pthread_mutexattr_getprotocol(), and
pthread_mutex_getprioceiling. The changes are in accordance to POSIX/SUSv4-2018.
Hinted by: DragonFlyBSD
Relnotes: yes
MFC after: 1 month
Differential Revision: D16722
The function retrieves the thread name previously set by
pthread_set_name_np(3). The name is cached in the process memory.
Requested by: Willem Jan Withagen <wjw@digiware.nl>
Man page update: Yuri Pankov <yuripv@yuripv.net>
Reviewed by: ian (previous version)
Discussed with: arichardson, bjk (man page)
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D16702
The timespecadd(3) family of macros were imported from NetBSD back in
r35029. However, they were initially guarded by #ifdef _KERNEL. In the
meantime, we have grown at least 28 syscalls that use timespecs in some
way, leading many programs both inside and outside of the base system to
redefine those macros. It's better just to make the definitions public.
Our kernel currently defines two-argument versions of timespecadd and
timespecsub. NetBSD, OpenBSD, and FreeDesktop.org's libbsd, however, define
three-argument versions. Solaris also defines a three-argument version, but
only in its kernel. This revision changes our definition to match the
common three-argument version.
Bump _FreeBSD_version due to the breaking KPI change.
Discussed with: cem, jilles, ian, bde
Differential Revision: https://reviews.freebsd.org/D14725
when to use assert, as well as providing a bad example of using
assert. While not strictly necessary, experience has shown issues
with poor assert choice happen often enough that this departure seems
warranted. Also, tighten up the previous example (there's no need
to have extra paragraphs or gratuitously long lines).
Reviewed by: emaste@ (earlier version)
It seems a shame to ruin the patina of the June 4, 1993 date
on abort.3, especially since it still matched the date of
the SCCS ID, but those are the rules.
Reported by: araujo
MFC after: 3 days
Sponsored by: Dell EMC
I didn't know abort2 existed until it was mentioned on a mailing list.
Mention it in related pages so others can find it easily.
MFC after: 3 days
Sponsored by: Dell EMC
Remove some statements which are no longer correct after ino64, and
clarify other.
The rewording is not in fact specific to ino64 and improvements are
useful on the stable branches.
Noted and reviewed by: bde
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
- Use `Em` with `.It` macro when referring to other libraries, instead of
`Xr`.
- Use `.Em` instead of `.Xr` when referring to libraries.
- Remove commented out lines.
MFC after: 1 month
Reported by: make manlint
Sponsored by: Dell EMC Isilon
Add a clock_nanosleep() syscall, as specified by POSIX.
Make nanosleep() a wrapper around it.
Attach the clock_nanosleep test from NetBSD. Adjust it for the
FreeBSD behavior of updating rmtp only when interrupted by a signal.
I believe this to be POSIX-compliant, since POSIX mentions the rmtp
parameter only in the paragraph about EINTR. This is also what
Linux does. (NetBSD updates rmtp unconditionally.)
Copy the whole nanosleep.2 man page from NetBSD because it is complete
and closely resembles the POSIX description. Edit, polish, and reword it
a bit, being sure to keep any relevant text from the FreeBSD page.
Reviewed by: kib, ngie, jilles
MFC after: 3 weeks
Relnotes: yes
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D10020
This function allows the caller to specify the reference clock
and choose between absolute and relative mode. In relative mode,
the remaining time can be returned.
The API is similar to clock_nanosleep(3). Thanks to Ed Schouten
for that suggestion.
While I'm here, reduce the sleep time in the semaphore "child"
test to greatly reduce its runtime. Also add a reasonable timeout.
Reviewed by: ed (userland)
MFC after: 2 weeks
Relnotes: yes
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D9656
Instead of failing with ENAMETOOLONG, which is swallowed by
pthread_set_name_np() anyway, truncate the given name to MAXCOMLEN+1
bytes. This is more likely what the user wants, and saves the
caller from truncating it before the call (which was the only
recourse).
Polish pthread_set_name_np(3) and add a .Xr to thr_set_name(2)
so the user might find the documentation for this behavior.
Reviewed by: jilles
MFC after: 3 days
Sponsored by: Dell EMC
Split the QUEUE_MACRO_DEBUG into QUEUE_MACRO_DEBUG_TRACE and
QUEUE_MACRO_DEBUG_TRASH.
Add the debug macrso QMD_IS_TRASHED() and QMD_SLIST_CHECK_PREVPTR().
Document these in queue.3.
Reviewed by: emaste
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D3984
queue.h header file and in the queue.3 manual page that they are O(n)
so should be used only in low-usage paths with short lists (otherwise
an STAILQ or TAILQ should be used).
Reviewed by: kib
- Add a sigevent(3) manpage to give a general overview of the sigevent
structure and the available notification mechanisms.
- Document that AIO requests contain a nested sigevent structure that can
be used to request completion notification.
- Expand the sigevent details in other manuals to note details such as
the extra values stored in a queued signal's information or in a posted
kevent.
Reviewed by: kib
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D7122
- Use Ta to separate column headers.
- Correct width of the 'Code' column in the last table.
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D7118
