generated from lib/csu/common/crtbrand.c (which ultimately ends up in
executables and shared libraries, via crt1.o, gcrt1.o or Scrt1.o).
For all arches except sparc, gcc emits the section directive for the
abitag struct in crtbrand.c with a PROGBITS type. However, newer
versions of binutils (after 2.16.90) require the section to be of NOTE
type, to guarantee that the .note.ABI-tag section correctly ends up in
the first page of the final executable.
Unfortunately, there is no clean way to tell gcc to use another section
type, so crtbrand.c (or the C files that include it) must be compiled in
multiple steps:
- Compile the .c file to a .s file.
- Edit the .s file to change the 'progbits' type to 'note', for the section
directive that defines the .note.ABI-tag section.
- Compile the .s file to an object file.
These steps are done in the invididual Makefiles for each applicable arch.
Reviewed by: kib
Stack creation code is changed to call _rtld_get_stack_prot() to get
the stack protection right. There is a race where thread is created
during dlopen() of dso that requires executable stacks. Then,
_rtld_get_stack_prot() may return PROT_READ | PROT_WRITE, but thread
is still not linked into the thread list. In this case, the callback
misses the thread stack, and rechecks the required protection
afterward.
Reviewed by: davidxu
Implement MACHINE_ARCH=mips64e[lb] to build N64 images. This replaces
MACHINE_ARCH=mipse[lb] TARGET_ABI=n64.
MACHINE_ARCH=mipsn32e[lb] has been added, but currently requires
WITHOUT_CDDL due to atomic issues in libzfs. I've not investigated
this much, but implemented this to preserve as much of the TARGET_ABI
functionality that I could. Since its presence doesn't affect the
working cases, I've kept it in for now.
Added mips64e[lb] to make universe, so more kernels build.
And I think this (finally) closes the curtain on the tbemd tree.
assembler source for libcompiler_rt as not needed executable stack. This
is done with a hammer instead of properly marking each assembly file
with section .note.GNU-stack to avoid modifying contributed source.
Discussed with: ed
- Add flags CVWAIT_ABSTIME and CVWAIT_CLOCKID for umtx kernel based
condition variable, this should eliminate an extra system call to get
current time.
- Add sub-function UMTX_OP_NWAKE_PRIVATE to wake up N channels in single
system call. Create userland sleep queue for condition variable, in most
cases, thread will wait in the queue, the pthread_cond_signal will defer
thread wakeup until the mutex is unlocked, it tries to avoid an extra
system call and a extra context switch in time window of pthread_cond_signal
and pthread_mutex_unlock.
The changes are part of process-shared mutex project.
in crt1.o. On other architectures crtbrand.c is included from crt1.c,
but that's not a C source code file on ia64. Instead it is compiled
separately and included in crt1.o using incremental linking.
Tested by: dim (previous version)
Approved by: kib (mentor)
the existing file descriptor. Instead, let dup2() atomically close the
old file descriptor when assigning the newly opened file to the same
descriptor. This closes a race in a multithreaded application where a
concurrent open() could allocate the existing file descriptor in between
the calls to close() and dup2().
PR: threads/79887
Submitted by: Dmitrij Tejblum tejblum of yandex-team.ru
Reviewed by: davidxu
MFC after: 1 week
In particular, this check avoids a warning when
extracting directory entries from certain GNU tar
archives that store directory contents.
MFC after: 3 days
implementing accurate logarithms in different bases. This is based
on an approach bde coded up years ago.
This function should always be inlined; it will be used in only a few
places, and rudimentary tests show a 40% performance improvement in
implementations of log2() and log10() on amd64.
The kernel takes a reduced argument x and returns the same polynomial
approximation as e_log.c, but omitting the low-order term. The low-order
term is much larger than the rest of the approximation, so the caller of
the kernel function can scale it to the appropriate base in extra precision
and obtain a much more accurate answer than by using log(x)/log(b).
