We are removing native bridge copy of fork.cpp, but need to
replace call to clone() when it's done for bionic's fork.
The code here will run all pre-/post-clone routines for *guest*,
while native bridge implementation will need to run the
corresponding *host* routines.
Bug: 145028007
Test: bionic-unit-tests
Change-Id: Ic5524e743caa287d7aaa8dc7e5d34acd1c7e1170
Bionic creates a single thread mapping to hold a thread's stack and static
TLS memory. Use PR_SET_VMA_ANON_NAME to name this region
"stack_and_tls:tid". dumpsys meminfo can report this region as "Stack"
memory.
The main thread's memory is instead named stack_and_tls:main, and the VMA
is renamed to stack_and_tls:main in a post-fork child.
For the main thread, and threads using pthread_attr_setstack, Bionic still
creates the stack_and_tls mapping, but it only has TLS memory in it.
Bug: http://b/134795155
Test: run "dumpsys meminfo" and verify that this CL increases the reported
stack memory usage from about 4MB to 21MB.
Change-Id: Id1f39ff083329e83426130b4ef94222ffacb90ae
Merged-In: Id1f39ff083329e83426130b4ef94222ffacb90ae
Add two functions to allow objects that own a file descriptor to
enforce that only they can close their file descriptor.
Use them in FILE* and DIR*.
Bug: http://b/110100358
Test: bionic_unit_tests
Test: aosp/master boots without errors
Test: treehugger
Change-Id: Iecd6e8b26c62217271e0822dc3d2d7888b091a45
To make it easier for Native Bridge implementations
to override these symbols.
Bug: http://b/67993967
Test: make
Change-Id: I4c53e53af494bca365dd2b3305ab0ccc2b23ba44
With this, stack frame 0 is the abort, not tgkill.
arm:
#00 pc 0001a41c /system/lib/libc.so (abort+63)
arm64:
#00 pc 000000000001d75c /system/lib64/libc.so (abort+120)
Also "include what you use" for <sys/syscall.h>.
Bug: N/A
Test: ran `crasher abort` and `crasher64 abort`
Change-Id: I6517ac67b39b4133e890d52efc115071c812958b
This was previously done only in fork() and pthread_create(), but this left raw
clone() with an invalid cached tid. Since the tid is used for pthread routines,
this led to unstable behavior after clone().
Test: ltp clone01 (see bug for more)
Test: mmma bionic/tests
Test: bionic-unit-tests-static --gtest_filter=*fork*:*clone*
Bug: 32612735
Bug: 32305649
Change-Id: I30eae5a8024b4c5da65476fcadfe14c6db35bb79
* Allow clone where both the child function and stack are null. It's
obviously wrong to ask to call a function without a stack, but it's not
necessarily wrong to supply no stack if you're also not supplying a
function.
* Reimplement fork in terms of the clone function, rather than using the
clone system call directly.
This is intended as a step towards enabling use of pid namespaces.
Change-Id: I03c89bd1dc540d8b4ed1c8fdf6644290744b9e91
In practice, with this implementation we never need to make a system call.
We get the main thread's tid (which is the same as our pid) back from
the set_tid_address system call we have to make during initialization.
A new pthread will have the same pid as its parent, and a fork child's
main (and only) thread will have a pid equal to its tid, which we get for
free from the kernel before clone returns.
The only time we'd actually have to make a getpid system call now is if
we take a signal during fork and the signal handler calls getpid. (That,
or we call getpid in the dynamic linker while it's still dealing with its
own relocations and hasn't even set up the main thread yet.)
Bug: 15387103
Change-Id: I6d4718ed0a5c912fc75b5f738c49a023dbed5189
This is a much simpler implementation that lets the kernel
do as much as possible.
Co-authored-by: Jörgen Strand <jorgen.strand@sonymobile.com>
Co-authored-by: Snild Dolkow <snild.dolkow@sonymobile.com>
Change-Id: Iad19f155de977667aea09410266d54e63e8a26bf
The kernel now maintains the pthread_internal_t::tid field for us,
and __clone was only used in one place so let's inline it so we don't
have to leave such a dangerous function lying around. Also rename
files to match their content and remove some useless #includes.
Change-Id: I24299fb4a940e394de75f864ee36fdabbd9438f9
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
