Commit Graph

10 Commits

Author SHA1 Message Date
Dmitry Vyukov a72dc86cdd tsan: tsan_interface.h: make constants static
Note that in C++ the static keyword is implicit for const objects.
In C however it is not, and we get clashes at link time after
including the header from more than one C file:

lib.a(bar.o):(.rodata+0x0): multiple definition of `__tsan_mutex_linker_init'
lib.a(foo.o):(.rodata+0x0): first defined here
lib.a(bar.o):(.rodata+0xc): multiple definition of `__tsan_mutex_not_static'
lib.a(foo.o):(.rodata+0xc): first defined here
<snip>
Indeed both foo.o and bar.o define the clashing symbols:

$ nm foo.o
<snip>
0000000000000000 R __tsan_mutex_linker_init
000000000000000c R __tsan_mutex_not_static
<snip>
Fix it by explicitly making the constants static.

Reviewed-in: https://reviews.llvm.org/D75820
Author: cota (Emilio G. Cota)
2020-03-10 09:13:41 +01:00
Dmitry Vyukov 76e961207b tsan: add fiber support
This patch adds functions for managing fibers:

__tsan_get_current_fiber()
__tsan_create_fiber()
__tsan_destroy_fiber()
__tsan_switch_to_fiber()
__tsan_set_fiber_name()

See the added tests for use examples.

Author: yuri (Yuri Per)
Reviewed in: https://reviews.llvm.org/D54889

[The previous commit of this change was reverted,
this is a resubmit with a squashed fix for check_analyze.sh
and COMMON_INTERCEPTOR_NOTHING_IS_INITIALIZED]

llvm-svn: 353947
2019-02-13 13:21:24 +00:00
Diana Picus 4152a09e55 Revert "tsan: add fiber support"
This reverts commit r353817 because we think it broke AARch64 and
PowerPC buildbots.

llvm-svn: 353939
2019-02-13 11:32:56 +00:00
Dmitry Vyukov 6e7089ad40 tsan: add fiber support
This patch adds functions for managing fibers:

__tsan_get_current_fiber()
__tsan_create_fiber()
__tsan_destroy_fiber()
__tsan_switch_to_fiber()
__tsan_set_fiber_name()

See the added tests for use examples.

Author: yuri (Yuri Per)
Reviewed in: https://reviews.llvm.org/D54889

llvm-svn: 353817
2019-02-12 10:11:58 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Dmitry Vyukov 9e2cd1c125 [tsan] Add Mutex annotation flag for constant-initialized __tsan_mutex_linker_init behavior
Add a new flag, _⁠_tsan_mutex_not_static, which has the opposite sense
of _⁠_tsan_mutex_linker_init. When the new _⁠_tsan_mutex_not_static flag
is passed to _⁠_tsan_mutex_destroy, tsan ignores the destruction unless
the mutex was also created with the _⁠_tsan_mutex_not_static flag.

This is useful for constructors that otherwise woud set
_⁠_tsan_mutex_linker_init but cannot, because they are declared constexpr.

Google has a custom mutex with two constructors, a "linker initialized"
constructor that relies on zero-initialization and sets
⁠_⁠_tsan_mutex_linker_init, and a normal one which sets no tsan flags.
The "linker initialized" constructor is morally constexpr, but we can't
declare it constexpr because of the need to call into tsan as a side effect.

With this new flag, the normal c'tor can set _⁠_tsan_mutex_not_static,
the "linker initialized" constructor can rely on tsan's lazy initialization,
and _⁠_tsan_mutex_destroy can still handle both cases correctly.

Author: Greg Falcon (gfalcon)
Reviewed in: https://reviews.llvm.org/D39095

llvm-svn: 316209
2017-10-20 12:08:53 +00:00
Kuba Mracek a7cad4fcb7 [tsan] Detect races on modifying accesses in Swift code
This patch allows the Swift compiler to emit calls to `__tsan_external_write` before starting any modifying access, which will cause TSan to detect races on arrays, dictionaries and other classes defined in non-instrumented modules. Races on collections from the Swift standard library and user-defined structs and a frequent cause of subtle bugs and it's important that TSan detects those on top of existing LLVM IR instrumentation, which already detects races in direct memory accesses.

Differential Revision: https://reviews.llvm.org/D31630

llvm-svn: 302050
2017-05-03 16:51:01 +00:00
Dmitry Vyukov 5fa9175e24 tsan: support linker init flag in __tsan_mutex_destroy
For a linker init mutex with lazy flag setup
(no __tsan_mutex_create call), it is possible that
no lock/unlock happened before the destroy call.
Then when destroy runs we still don't know that
it is a linker init mutex and will emulate a memory write.
This in turn can lead to false positives as the mutex
is in fact linker initialized.

Support linker init flag in destroy annotation to resolve this.

llvm-svn: 301795
2017-05-01 10:01:13 +00:00
Kuba Mracek d1be869744 [tsan] Publish the TSan external API in tsan_interface.h
Let's make the TSan external API available and commented in the public header:

    void *__tsan_external_register_tag(const char *object_type);
    void __tsan_external_assign_tag(void *addr, void *tag);
    void __tsan_external_read(void *addr, void *caller_pc, void *tag);
    void __tsan_external_write(void *addr, void *caller_pc, void *tag);

Differential Revision: https://reviews.llvm.org/D32358

llvm-svn: 301003
2017-04-21 17:25:47 +00:00
Dmitry Vyukov 8096a8c86f tsan: add new mutex annotations
There are several problems with the current annotations (AnnotateRWLockCreate and friends):
- they don't fully support deadlock detection (we need a hook _before_ mutex lock)
- they don't support insertion of random artificial delays to perturb execution (again we need a hook _before_ mutex lock)
- they don't support setting extended mutex attributes like read/write reentrancy (only "linker init" was bolted on)
- they don't support setting mutex attributes if a mutex don't have a "constructor" (e.g. static, Java, Go mutexes)
- they don't ignore synchronization inside of lock/unlock operations which leads to slowdown and false negatives
The new annotations solve of the above problems. See tsan_interface.h for the interface specification and comments.

Reviewed in https://reviews.llvm.org/D31093

llvm-svn: 298809
2017-03-26 15:27:04 +00:00