One possible way the recursion can happen is during fork: suppose
that fork is called from early code that did not triggered
jemalloc(3) initialization yet. Then we lock thr_malloc lock, and
call malloc_prefork() that might require initialization of jemalloc
pthread_mutexes, calling into libthr malloc. It is safe to allow
recursion for this occurence.
PR: 252579
Reported by: Vasily Postnicov <shamaz.mazum@gmail.com>
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Without wrapping, rtld services and malloc(3) are not guaranteed
to operate correctly in the forked child.
Reviewed by: markj
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D28088
We need at least thr_malloc ready. The situation is possible e.g. in case
of libthr being listed in DT_NEEDED before some of its consumers.
Reported and tested by: lev
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
This seems to be required by recent clang asan.
I do not see other way than put the symbol under FBSD_1.0 version.
PR: 251112
Reported by: Andrew Stitcher <astitcher@apache.org>
Reviewed by: emaste
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D27389
pthread_get_name_np() and pthread_set_name_np().
This re-applies r361770 after compatibility fixes.
Reviewed by: antoine, jkim, markj
Tested by: antoine (exp-run)
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D25117
for pthread_get_name_np() and pthread_set_name_np(), to be
compatible with Linux.
PR: 238404
Proposed and reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D25117
The function allows to peek at the thread exit status and even see
return value, without joining (and thus finally destroying) the target
thread.
Reviewed by: markj
Sponsored by: The FreeBSD Foundation (kib)
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D23676
exited but not yet joined thread.
Before, if the thread exited but was not yet joined, we returned
ESRCH.
According to IEEE Std 1003.1™-2017 recommendation in the
description of pthread_cancel(3):
If an implementation detects use of a thread ID after the end of its
lifetime, it is recommended that the function should fail and report
an [ESRCH] error.
So it seems desirable to not return ESRCH until the lifetime of the
thread ID ends. According to the section 2.9.2 Thread IDs,
The lifetime of a thread ID ends after the thread terminates if it
was created with the detachstate attribute set to
PTHREAD_CREATE_DETACHED or if pthread_detach() or pthread_join()
has been called for that thread.
In other words, lifetime for thread ID of exited but not yet joined thread
did not ended yet.
Prompted by: cperciva
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Ensure proper handshake to transfer sigfastblock(2) blocking word
ownership from rtld to libthr.
Unfortunately sigfastblock(2) is not enough to stop intercepting
signals in libthr, because critical sections must ensure more than
just signal blocking.
Tested by: pho
Disscussed with: cem, emaste, jilles
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D12773
If robust mutex' owner terminated, causing kernel-assisted state
recovery, and then pthread_mutex_destroy() is executed as the next
action, assert is triggered about mutex still being on the list.
Ignore the mutex linkage in pthread_mutex_destroy() for shared robust
mutexes with dead owner, same as for enqueue_mutex().
Reported by: avg
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
In some corner cases of static linking and unexpected libraries order
on the linker command line, libc symbol might preempt the same libthr
symbol, in which case libthr jump table points back to libc causing
either infinite recursion or loop. Handle all of such symbols by
using private libthr names for them, ensuring that the right pointers
are installed into the table.
In collaboration with: arichardson
PR: 239475
Tested by: pho
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D21088
In some corner cases of static linking and unexpected libraries order
on the linker command line, libc symbol might preempt the same libthr
symbol, in which case libthr jump table points back to libc causing
either infinite recursion or loop. Handle all of such symbols by
using private libthr names for them, ensuring that the right pointers
are installed into the table.
In collaboration with: arichardson
PR: 239475
Tested by: pho
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D21088
If dso uses initial exec TLS mode, rtld tries to allocate TLS in
static space. If there is no space left, the dlopen(3) fails. If space
if allocated, initial content from PT_TLS segment is distributed to
all threads' pcbs, which was missed and caused un-initialized TLS
segment for such dso after dlopen(3).
The mode is auto-detected either due to the relocation used, or if the
DF_STATIC_TLS dynamic flag is set. In the later case, the TLS segment
is tried to allocate earlier, which increases chance of the dlopen(3)
to succeed. LLD was recently fixed to properly emit the flag, ld.bdf
did it always.
Initial test by: dumbbell
Tested by: emaste (amd64), ian (arm)
Tested by: Gerald Aryeetey <aryeeteygerald_rogers.com> (arm64)
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D19072
This is not required of a compliant implementation, but it's easy to
check for and helps improve compatibility with other common
implementations. Moreover, it's consistent with our
pthread_mutex_destroy().
PR: 234805
Reviewed by: jhb, kib, ngie
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D19496
When libthr is statically linked into the binary, order of the
constructors execution is not deterministic. It is possible for the
application constructor to use pthread_mutex_* functions before the
libthr initialization was done.
Handle it by:
- making thr_malloc.c locking functions operational when curthread is not
yet set;
- making __thr_malloc_init() idempotent, allowing more than one call to it;
- unconditionally calling __thr_malloc_init() before initializing
a process-private mutex.
Reported and tested by: mmel
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
The need to use libc malloc(3) from some places in libthr always
caused issues. For instance, per-thread key allocation was switched to
use plain mmap(2) to get storage, because some third party mallocs
used keys for implementation of calloc(3).
Even more important, libthr calls calloc(3) during initialization of
pthread mutexes, and jemalloc uses pthread mutexes. Jemalloc provides
some way to both postpone the initialization, and to make
initialization to use specialized allocator, but this is very fragile
and often breaks. See the referenced PR for another example.
Add the small malloc implementation used by rtld, to libthr. Use it in
thr_spec.c and for mutexes initialization. This avoids the issues with
mutual dependencies between malloc and libthr in principle. The
drawback is that some more allocations are not interceptable for
alternate malloc implementations. There should be not too much memory
use from this allocator, and the alternative, direct use of mmap(2) is
obviously worse.
PR: 235211
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D18988
Also remove logic to avoid unnecessary stores to the global variable.
Thread creation and destruction are heavy enough that any supposed savings
is in the noise.
MFC after: 2 weeks
Sponsored by: Dell EMC Isilon
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
Call _thr_check_init() before reading curthread in pthread_testcancel().
If a constructor in a library creates a semaphore via sem_init() and
then waits for it via sem_wait(), the program can core dump in
_pthread_testcancel() called from sem_wait(). This is because the
semaphore implementation lives in libc, so the library's constructors
can be run before libthr's constructors.
Reported by: arichardson
Reviewed by: kib
Obtained from: CheriBSD
MFC after: 1 week
Sponsored by: DARPA / AFRL
Differential Revision: https://reviews.freebsd.org/D14786
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
Mainly focus on files that use BSD 3-Clause license.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
Initially, only tag files that use BSD 4-Clause "Original" license.
RelNotes: yes
Differential Revision: https://reviews.freebsd.org/D13133
Fix regression by r318539. The sysutils/pstack uses library libthread_db to
read information about threads state. The function pt_ta_new makes lookup of
several key symbols including _thread_keytable. But r318539 mades this field
static. It causes silent ignore of libthr library by pstack and as result
sysutils/pstack doesn't output any thread information.
This fix changes this field back to non-static.
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D11738
Following up on r320900, where the check for negative count values was
removed, add a check to prevent integer overflow. This is to account that
b_count, b_waiters but most importantly the total number of threads in
the system are signed values.
Discussed with: kib
MFC after: 2 weeks
__thr_setcontext() mistakenly tested for the presence of SIGCANCEL
in its local ucontext_t instead of the parameter. Therefore,
if a thread calls setcontext() with a context whose signal mask
contains SIGTHR (a.k.a. SIGCANCEL), that signal will be blocked,
preventing the thread from being cancelled or suspended.
Reported by: gcc 6.1 via RISC-V tinderbox
Reviewed by: kib
MFC after: 3 days
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D10933
Fix warnings about:
- redundant declarations
- a local variable shadowing a global function (dlinfo)
- an old-style function definition (with an empty parameter list)
- a variable that is possibly used uninitialized
"make tinderbox" passes this time, except for a few unrelated
kernel failures.
Reviewed by: kib
MFC after: 3 days
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D10870
People tweaking the build system or compilers tend to look into
the Makefile and not into the source. Having some warning controls
in the Makefile and some in the source code is surprising.
Pragmas have the advantage that they leave the warnings enabled
for more code, but that advantage isn't very relevant in these cases.
Requested by: kib
Reviewed by: kib
MFC after: 3 days
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D10832
This no longer seems useful. Remove it.
This was prompted by a "cast discards volatile qualifier" warning
in libthr when WARNS=6.
Reviewed by: kib
MFC after: 3 days
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D10832
This was prompted by a compiler warning about 'ret' shadowing
a local variable in the callers of the macro.
Reviewed by: kib
MFC after: 3 days
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D10832
Fix warnings about the following when WARNS=6 (which I will commit soon):
- casting away const
- no previous 'extern' declaration for non-static variable
- others as explained by #pragmas and comments
- unused parameters
The last is the only functional change.
Reviewed by: kib
MFC after: 3 days
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D10808
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
Replace uses of the GCC __nonnull__ attribute with the clang nullability
qualifiers. The replacement should be transparent for clang developers as
the new qualifiers will produce the same warnings and will be useful for
static checkers but will not cause aggressive optimizations.
GCC will not produce such warnings and developers will have to use
upgraded GCC ports built with the system headers from r312538.
Hinted by: Apple's Libc-1158.20.4, Bionic libc
MFC after: 11.1 Release
Differential Revision: https://reviews.freebsd.org/D9004
Leave robust-protected region before checking for cancellation by
calling _thr_testcancel(). Otherwise, if cancelling request was
pending, the cancel handler is called with the dandling inact_mtx,
which triggers an assert if any mutex operation is performed by the
handler.
Reported and tested by: Dimitri Staessens <dimitri.staessens@intec.ugent.be>
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
