Commit graph

19 commits

Author SHA1 Message Date
Yi Kong
32bc0fcf69 Modernize codebase by replacing NULL with nullptr
Fixes -Wzero-as-null-pointer-constant warning.

Test: m
Bug: 68236239
Change-Id: I5b4123bc6709641315120a191e36cc57541349b2
2018-08-02 18:09:44 -07:00
Yabin Cui
6b9c85b36d Support priority inheritance mutex in 64bit programs.
Bug: http://b/29177606
Test: run bionic-unit-tests on walleye.
Test: run bionic-unit-tests-glibc on host.
Change-Id: Iac349284aa73515f384e7509445f87434757f59e
2018-01-24 16:11:07 -08:00
Tom Cherry
ac49cedc7e Always use CLOCK_MONOTONIC for pthreads and semaphores
pthread's and semaphore's default behavior is to use CLOCK_REALTIME,
however this behavior is essentially never intended, as that clock is
prone to change discontinuously.

What users really intend is to use CLOCK_MONOTONIC, however only
pthread_cond_timedwait() provides this as an option and even there, a
large amount of existing code does not opt into CLOCK_MONOTONIC.

We have seen numerous bugs directly attributable to this difference.
Therefore, we provide this general workaround to always use
CLOCK_MONOTONIC for waiting, regardless of what the input timespec
is.

Specifically this impacts the below APIs:
pthread_mutex_timedlock()
pthread_cond_timedwait()
pthread_rwlock_timedrdlock()
pthread_rwlock_timedwrlock()
sem_timedwait()

Test: boot bullhead, boot sailfish
Test: bionic pthread/semaphore unit tests
Test: check that pthread_cond_timedwait() timeouts are uneffected by
      CLOCK_REALTIME time changes

Bug: 64694413
Bug: 64623895
Bug: 35756266
Bug: 35678943
Change-Id: Ibba98f5d88be1c306d14e9b9366302ecbef6d534
2017-08-18 09:11:05 -07:00
Yabin Cui
c9a659c57b Use FUTEX_WAIT_BITSET to avoid converting timeouts.
Add unittests for pthread APIs with timeout parameter.

Bug: 17569991

Change-Id: I6b3b9b2feae03680654cd64c3112ce7644632c87
2015-11-19 13:42:03 -08:00
Elliott Hughes
4c5891d93d valgrind can't find syscall because we didn't put it in <unistd.h>.
Change-Id: I1e47291d4476bd2816138a8cf58f29d4986d39e3
2015-02-19 22:49:44 -08:00
Elliott Hughes
1ee46520ca Return the actual success result from __futex.
futex(2) can return non-zero successes.

Bug: 15195455
Change-Id: I7818bc922a5a2df31228ff72c169320b5e69a544
2014-05-29 10:27:55 -07:00
Elliott Hughes
b30aff405a Revert "Revert "Lose the hand-written futex assembler.""
The problem with the original patch was that using syscall(3) means that
errno can be set, but pthread_create(3) was abusing the TLS errno slot as
a pthread_mutex_t for the thread startup handshake.

There was also a mistake in the check for syscall failures --- it should
have checked against -1 instead of 0 (not just because that's the default
idiom, but also here because futex(2) can legitimately return values > 0).

This patch stops abusing the TLS errno slot and adds a pthread_mutex_t to
pthread_internal_t instead. (Note that for LP64 sizeof(pthread_mutex_t) >
sizeof(uintptr_t), so we could potentially clobber other TLS slots too.)

I've also rewritten the LP32 compatibility stubs to directly reuse the
code from the .h file.

This reverts commit 75c55ff84e.

Bug: 15195455
Change-Id: I6ffb13e5cf6a35d8f59f692d94192aae9ab4593d
2014-05-28 18:31:15 -07:00
Narayan Kamath
75c55ff84e Revert "Lose the hand-written futex assembler."
This reverts commit ced906c849.

Causes issues on art / dalvik due to a broken return value
check and other undiagnosed issues.

bug: 15195455

Change-Id: I5d6bbb389ecefb0e33a5237421a9d56d32a9317c
2014-05-28 18:03:01 +00:00
Elliott Hughes
ced906c849 Lose the hand-written futex assembler.
Also stop exporting 'futex'.

Bug: 12250341
Change-Id: Icc4fa4296cd04dfe0d1061822c69e2eb40c3433a
2014-05-22 19:49:11 -07:00
Elliott Hughes
d5ed63a6a8 Hide most of the private futex functions.
Also hide part of the system properties compatibility code, since
we needed to touch that to keep it building.

I'll remove __futex_syscall4 and futex in a later patch.

Bug: 11156955
Change-Id: Ibbf42414c5bb07fb9f1c4a169922844778e4eeae
2014-05-21 18:30:00 -07:00
Elliott Hughes
3973de9616 Hide __futex_wake_ex and __futex_wait_ex.
Also remove some cruft that isn't needed now we're using uapi headers.

Bug: 11156955
Change-Id: I936b9c5b01d8bd6bfb2e5bc0e3f86cd86739cc04
2014-05-16 12:53:31 -07:00
Elliott Hughes
5eccb9646d Fix aarch64 futex assembly routines.
Also make the other architectures more similar to one another,
use NULL instead of 0 in calling code, and remove an unused #define.

Change-Id: I52b874afb6a351c802f201a0625e484df6d093bb
2013-12-20 16:58:06 -08:00
Elliott Hughes
877ec6d904 Fix pthread_join.
Let the kernel keep pthread_internal_t::tid updated, including
across forks and for the main thread. This then lets us fix
pthread_join to only return after the thread has really exited.

Also fix the thread attributes of the main thread so we don't
unmap the main thread's stack (which is really owned by the
dynamic linker and contains things like environment variables),
which fixes crashes when joining with an exited main thread
and also fixes problems reported publicly with accessing environment
variables after the main thread exits (for which I've added a new
unit test).

In passing I also fixed a bug where if the clone(2) inside
pthread_create(3) fails, we'd unmap the child's stack and TLS (which
contains the mutex) and then try to unlock the mutex. Boom! It wasn't
until after I'd uploaded the fix for this that I came across a new
public bug reporting this exact failure.

Bug: 8206355
Bug: 11693195
Bug: https://code.google.com/p/android/issues/detail?id=57421
Bug: https://code.google.com/p/android/issues/detail?id=62392
Change-Id: I2af9cf6e8ae510a67256ad93cad891794ed0580b
2013-11-18 19:48:11 -08:00
Elliott Hughes
c3f114037d <pthread.h> fixes and pthread cleanup.
<pthread.h> was missing nonnull attributes, noreturn on pthread_exit,
and had incorrect cv qualifiers for several standard functions.

I've also marked the non-standard stuff (where I count glibc rather
than POSIX as "standard") so we can revisit this cruft for LP64 and
try to ensure we're compatible with glibc.

I've also broken out the pthread_cond* functions into a new file.

I've made the remaining pthread files (plus ptrace) part of the bionic code
and fixed all the warnings.

I've added a few more smoke tests for chunks of untested pthread functionality.

We no longer need the libc_static_common_src_files hack for any of the
pthread implementation because we long since stripped out the rest of
the armv5 support, and this hack was just to ensure that __get_tls in libc.a
went via the kernel if necessary.

This patch also finishes the job of breaking up the pthread.c monolith, and
adds a handful of new tests.

Change-Id: Idc0ae7f5d8aa65989598acd4c01a874fe21582c7
2013-10-31 12:31:16 -07:00
Elliott Hughes
36fa67bcdd Ensure header files using __BEGIN_DECLS include sys/cdefs.h.
We keep fixing these one-by-one; let's fix them all at once.

Found thus:

  find . -name *.h | xargs grep -L sys/cdefs.h | xargs grep -l BEGIN_DECL | xargs grep -L sys/types

Change-Id: I188842aa2484dc6176e96556d57c38a0f785b59b
2013-06-05 17:58:08 -07:00
Elliott Hughes
3e898476c7 Revert "Revert "More pthreads cleanup.""
This reverts commit 6f94de3ca4

(Doesn't try to increase the number of TLS slots; that leads to
an inability to boot. Adds more tests.)

Change-Id: Ia7d25ba3995219ed6e686463dbba80c95cc831ca
2013-02-12 15:27:18 -08:00
Elliott Hughes
6f94de3ca4 Revert "More pthreads cleanup."
This reverts commit 2a1bb4e646

Change-Id: Ia443d0748015c8e9fc3121e40e68258616767b51
2013-02-12 06:06:22 +00:00
Elliott Hughes
2a1bb4e646 More pthreads cleanup.
POSIX says pthread_create returns EAGAIN, not ENOMEM.

Also pull pthread_attr_t functions into their own file.

Also pull pthread_setname_np into its own file.

Also remove unnecessary #includes from pthread_key.cpp.

Also account for those pthread keys used internally by bionic,
so they don't count against the number of keys available to user
code. (They do with glibc, but glibc's limit is the much more
generous 1024.)

Also factor out the common errno-restoring idiom to reduce gotos.

Bug: 6702535
Change-Id: I555e66efffcf2c1b5a2873569e91489156efca42
2013-02-11 14:56:39 -08:00
David 'Digit' Turner
6304d8b218 Use private futexes for semaphores, unless they are initialized with pshared != 0.
Change-Id: I534e36a7171cd37037ae03b910ba71ea6968286d
Note: previously, sem_init() would return an error if pshared != 0.
2010-06-08 17:04:49 -07:00