These allow one to non-destructively iterate over the set or clear bits
in a bitset. The motivation is that we have several code fragments
which iterate over a CPU set like this:
while ((cpu = CPU_FFS(&cpus)) != 0) {
cpu--;
CPU_CLR(cpu, &cpus);
<do something>;
}
This is slow since CPU_FFS begins the search at the beginning of the
bitset each time. On amd64 and arm64, CPU sets have size 256, so there
are four limbs in the bitset and we do a lot of unnecessary scanning.
A second problem is that this is destructive, so code which needs to
preserve the original set has to make a copy. In particular, we have
quite a few functions which take a cpuset_t parameter by value, meaning
that each call has to copy the 32 byte cpuset_t.
The new macros address both problems.
Reviewed by: cem, kib
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D32028
iflib now supports mapping each (TX,RX) queue pair to the same CPU
(default), to separate CPUs, or to a pair of physical and logical CPUs
that share the same L2 cache. The mapping mechanism supports unequal
numbers of TX and RX queues, with the excess queues always being
mapped to consecutive physical CPUs. When the platform cannot
distinguish between physical and logical CPUs, all are treated as
physical CPUs. See the comment on get_cpuid_for_queue() for the
entire matrix.
The following device-specific tunables influence the mapping process:
dev.<device>.<unit>.iflib.core_offset (existing)
dev.<device>.<unit>.iflib.separate_txrx (existing)
dev.<device>.<unit>.iflib.use_logical_cores (new)
The following new, read-only sysctls provide visibility of the mapping
results:
dev.<device>.<unit>.iflib.{t,r}xq<n>.cpu
When an iflib driver allocates TX softirqs without providing reference
RX IRQs, iflib now binds those TX softirqs to CPUs using the above
mapping mechanism (that is, treats them as if they were TX IRQs).
Previously, such bindings were left up to the grouptaskqueue code and
thus fell outside of the iflib CPU mapping strategy.
Reviewed by: kbowling
Tested by: olivier, pkelsey
MFC after: 3 weeks
Differential Revision: https://reviews.freebsd.org/D24094
That is, provide wrappers around the atomic_testandclear and
atomic_testandset primitives.
Submitted by: jeff
Reviewed by: cem, kib, markj
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D22702
An upcoming patch to use the bitset macros for tracking vm page
dump information could conceivably need more than INT_MAX bits.
Expand the bit type to long so that the extra range is available
on 64-bit platforms where it would most likely be needed.
CPUSET_COUNT and DOMAINSET_COUNT are also modified to remain of
type `int`.
Reviewed by: kib, markj
Approved by: scottl (implicit)
MFC after: 1 week
Sponsored by: Ampere Computing, Inc.
Differential Revision: https://reviews.freebsd.org/D26190
s/BIT_NAND/BIT_ANDNOT/, and for CPU and DOMAINSET too. The actual
implementation is "and not" (or "but not"), i.e. A but not B.
Fortunately this does appear to be what all existing callers want.
Don't supply a NAND (not (A and B)) operation at this time.
Discussed with: jeff
Reviewed by: cem
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D22791
We have a couple optimizations for when the bitset is known to be just
one word. But with dynamically sized bitsets, it was actually more work
to determine the size than just to do the necessary computation. Now,
only use the optimization when the size is known to be constant.
Reviewed by: markj
Discussed with: jeff
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D22639
This code has not been updated since 2016, and it looks like it has
rotted quite a bit since. It does not build against the current set
of phoenix sources -- I had to hack both the kernel headers and the
newlib headers up to get it to build, and I still have no idea if it
actually links or runs. It seems like the project itself has moved
away from newlib and to its own C library:
https://phoenix-rtos.com/documentation/libc/README.md
So since there's no interest from the phoenix folks to maintain this,
and it has a significant amount of non-standard code that we try to
keep up-to-date (without actually testing it), just punt it all.
I've had this lying around for probably a year or two at this point.
It just changes all the instance of "errno" from a common symbol to an
extern. I can't offhand recall where the actual definition is, but it
certainly exists in the generic code.
Convert all the libc/ subdir makes into the top-level Makefile. This
allows us to build all of libc from the top Makefile without using any
recursive make calls. This is faster and avoids the funky lib.a logic
where we unpack subdir archives to repack into a single libc.a. The
machine override logic is maintained though by way of Makefile include
ordering, and source file accumulation in libc_a_SOURCES.
There's a few dummy.c files that are no longer necessary since we aren't
doing the lib.a accumulating, so punt them.
The winsup code has been pulling the internal newlib ssp library out,
but that doesn't exist anymore, so change that to pull the objects.
This kills off the last configure script under libc/ and folds it
into the top newlib configure script. The a lot of the logic was
already in the top configure script, so move what's left into a
libc/acinclude.m4 file.
Remove dependency on __sdidinit member of struct _reent to check
object initialization. Like __sdidinit, the __cleanup member of
struct _reent is initialized in the __sinit() function. Checking
initialization against __cleanup serves the same purpose and will
reduce overhead in the __sfp() function in a follow up patch.
The crt0.o was handled in a subdir-by-subdir basis: it would be compiled
in one (e.g. libc/sys/$arch/), then copied up one level (libc/sys/), then
copied up another (libc/) before finally being copied & installed in the
top newlib dir. The libc/sys/ copy was cleaned up, and then the top dir
was changed to copy it directly out of the libc/sys/$arch/ dir. But the
libc/sys/ copy to libc/ was left behind. Clean that up now too.
When migrating the manual to the top-level, the include order was
sorted by name of the subdir. But this changed the chapter order
of the manual in the process. Change the sorting back to match
existing chapters and update the comments to explain.
The top-level newlib dir already takes care of recursing into the
sys/xxx/include/ subdirs and installing any headers found, so the
rtems subdir doesn't need to do this itself.
This is used in a bunch of places, but nowhere is it ever set, and
nowhere can I find any documentation, nor can I find any other project
using it. So delete the flags to simplify.
These targets don't actually cross-compile -- they try to pull some
objects out of the host's /lib/libc.a, /lib/libm.a, and /lib/crt0.o
directly and merge them into newlib's own libraries. This is hard
to keep working and impossible to test. Considering the vintage of
such targets, and gcc dropping them many many years ago, drop them
from newlib too. This will make cleaning up the build a lot easier.
The machine/{configure,Makefile} files exist only to fan out to the
specific machine/$arch/ subdir. We already have all that same info
in the phoenix/ dir itself, so by moving the recursive configure and
make calls into it, we can cut off this logic entirely and save the
overhead.
These were never added to the tree, and as we transition from autoconf
to automake, it really wants the latter subdirs to always exist. These
don't, so delete the logic.
This was only ever used for i?86-pc-linux-gnu targets, but that's been
broken for years, and has since been dropped. So clean this up too.
This also deletes the funky objectlist logic since it only existed for
the libtool libraries. Since it was the only thing left in the small
Makefile.shared file, we can punt that too.
This was only used by the i?86-pc-linux-gnu target which we've removed,
and even though it's using a "sys/linux/" dir to make it sound like it
only depends on the Linux kernel, it's actually tied to glibc APIs built
on top of Linux. Since the code relies on internal glibc APIs and has
been broken for some time, punt it all. If someone wants to bring it
back, they can try and actually keep the Linux-vs-glibc APIs separate.
Now that we use AC_NO_EXECUTABLES, and we require a recent version of
autoconf, we don't need to define our own copies of these macros. So
switch to the standard AC_PROG_CC.
This logic was added to libc & libm to get it working again after some
reworks in the CPP handling, but now that that's settled, let's move
this to the common newlib configure logic. This will make it easier
to consolidate all the configure calls into the top-level newlib dir.
This does create a lot of noise in the generate scripts, but that's
because of the ordering of the calls, not because of correctness. We
will try to draw that back down in follow up commits as we modernize
the toolchain calls in here.
THe stdio subdir is actually required by the documentation. The
stdio/def is handled dynamically, but libc.texi always expects it
to be included, and fails if it isn't. So making it required when
building docs is safe.
The xdr subdir is handled dynamically, but it doesn't include any
docs, so the dynamic logic isn't (currently) adding any value. So
making it required when building docs is safe.
That leaves: iconv, stdio64, posix, and signal subdirs. The chapters
have a little disclaimer saying they are system-dependent, but even
then, imo having stable manuals regardless of the target is preferable,
and we can add more disclaimer language to these chapters if we want.
This doesn't touch the man page codepaths, just the info/pdf.
Let automake manage whether the objects are included in lib.a. This
fixes failures after to commit 71086e8b2d70c1e71a8372f35d9901505fc72905
("newlib: delete (most) redundant lib_a_CCASFLAGS=$(AM_CCASFLAGS)") due
to automake generating different set of implicit rules, and the code in
here assuming the names of the generated objects.
When we had configure scripts in subdirs, the newlib_basedir value
was computed relative to that, and it'd be the same when used in the
Makefile in the same dir. With many subdir configure scripts removed,
the top-level configure & Makefile can't use the same relative path.
So switch the subdir Makefiles over to abs_newlib_basedir when they
use -I to find source headers.
Do this for all subdirs, even ones with configure scripts and where
newlib_basedir works. This makes the code consistent, and avoids
surprises if the configure script is ever removed in the future as
part of merging to the higher level.
Some of the subdirs were using -I$(newlib_basedir)/../newlib/ for
some reason. Collapse those too since newlib_basedir points to the
newlib source tree already.
When using the top-level configure script but subdir Makefiles, the
newlib_basedir value gets a bit out of sync: it's relative to where
configure lives, not where the Makefile lives. Move the abs setting
from the top-level configure script into acinclude.m4 so we can rely
on it being available everywhere. Although this commit doesn't use
it anywhere, just lays the groundwork.
The machine configure scripts are all effectively stub scripts that
pass the higher level options to its own makefile. There were only
three doing custom tests. The rest were all effectively the same as
the libc/ configure script.
So instead of recursively running configure in all of these subdirs,
generate their makefiles from the top-level configure. For the few
unique ones, deploy a pattern of including subdir logic via m4:
m4_include([machine/nds32/acinclude.m4])
Some of the generated machine makefiles have a bunch of extra stuff
added to them, but that's because they were inconsistent in their
configure libtool calls. The top-level has it, so it exports some
new vars to the ones that weren't already.
The sys configure scripts are almost all effectively stub scripts that
pass the higher level options to its own makefile. The phoenix & linux
ones are a bit more complicated with nested subdirs, so those have been
left alone for now. Plus, I don't really have a way of testing them.
There's no need to have a sys/ subdir just to copy the sys/$arch/crt0.o
up to sys/crt0.o, and then have libc/ copy sys/crt0.o up again. Just
have libc/ refer to sys/$arch/crt0.o directly and drop the intermediate
makefile entirely.
The sys/{configure,Makefile} files exist to fan out to the specific
sys/$arch/ subdir, and to possibly generate a crt0. We already have
all that same info in the libc/ dir itself, so by moving the recursive
configure and make calls into it, we can cut off some of this logic
entirely and save the overhead.
For arches that don't have a sys subdir, it means they can skip the
logic entirely.
The sys subdir itself is kept for the crt0 logic, for now. We'll try
and clean that up next.
It's unclear why this was added originally, but assuming it was needed
20 years ago, it shouldn't be explicitly required nowadays. Current
versions of autotools already take care of exporting LDFLAGS to the
Makefile as needed (things are actually getting linked). That's why
the configure diffs show LDFLAGS still here, but shifted to a diff
place in the output list. A few dirs stop exporting LDFLAGS, but
that's because they don't do any linking, only compiling, so it's
correct.
As for the use of $ldflags instead of the standard $LDFLAGS, I can't
really explain that at all. Just use the right name so users don't
have to dig into why their setting isn't respected, and then use a
non-standard name instead. Adjust the testsuite to match.
This define is only used by newlib internally, so stop exporting it
as HAVE_INITFINI_ARRAY since this can conflict with defines packages
use themselves.
We don't really need to add _ to HAVE_INIT_FINI too since it isn't
exported in newlib.h, but might as well be consistent here.
We can't (easily) add this to newlib_cflags like HAVE_INIT_FINI is
because this is based on a compile-time test in the top configure,
not on plain shell code in configure.host. We'd have to replicate
the test in every subdir in order to have it passed down.
Currently this is only enabled in the top-level as that's the only
place where it seemed to be used. But the libc/sys/phoenix/ dir
also uses this functionality, but fails to explicitly enable it.
Automake workedaround it, but generated warnings. Move the option
to NEWLIB_CONFIGURE so all dirs get it automatically iff they end
up using the option. If they don't use the option, there's no
difference to the generated code.
Since AM_INIT_AUTOMAKE calls AC_PROG_AWK, and some configure.ac
scripts call it too, we end up testing for awk multiple times. If
we change NEWLIB_CONFIGURE to require the macro instead, then it
makes sure it's always expanded, but only once.
While we're here, do the same thing with AC_PROG_INSTALL since it
is also called by AM_INIT_AUTOMAKE, although it doesn't currently
result in duplicate configure checks.
