Summary: This patch names the thread inside `ObserverManager::NextQueue`, similar to the vector of threads in `ObserverManager::CurrentQueue`.

Reviewed By: yfeldblum

Differential Revision: D15746165

fbshipit-source-id: 02df5616dcc2af27f318088c051a49d14df9a4df

Summary:
Some optimizations and changes to make mutex migrations easier:
- Add exception handling support, this allows using lock_combine pretty much
  anywhere a unique_lock would be used and makes transitioning between lock
  methods easier and more efficient as users aren't required to maintain their
  own unions anywhere (eg. with folly::Try)
- Add support for big return values so people can return anything from the
  critical section.  Without this, users would have to use code of the following
  form, which is prone to false sharing with metadata for the waiting thread
```
auto value = ReturnValue{};
mutex.lock_combine([&]() {
  value = critical_section();
});
```
- Add some optimizations like inlining the combine codepath and an optimistic
  load to elide a branch.  This gets us a ~8% throughput improvement from
  before.  More importantly, This prevents compilers from messing up the
  generated code to dereference the waiter node whenever they feel like.
- Defer time publishing for combinable threads until a preemption.  This gets us
  to the same level of efficiency as std::atomic even on broadwell, takes us to
  7x of the baseline (std::mutex) on the NUMA-less machines and almost perfectly
  parallel in the moderate concurrency levels.  I suspect we can do better with
  NUMA-awareness, but that's for another diff

Reviewed By: yfeldblum

Differential Revision: D15522658

fbshipit-source-id: 420f4202503305d57b6bd59a9a4ecb67d4dd3c2e

Summary:
[Folly] Rename `to_underlying_type` to `to_underlying`, following the pattern of `to_unsigned` and `to_signed`.

(Note: this ignores all push blocking failures!)

Reviewed By: mzlee

Differential Revision: D15776448

fbshipit-source-id: d1f87e917c22a1aa47fb5e37a3ecf7032cec0d48

Summary:
The anticipated (and desired) effect of this change is to make it so that `SKIP` in `SetUp` will actually always skip the test. Right now, test behavior depends on the setting `FOLLY_SKIP_AS_FAILURE` — when this is false, the test will get **executed** despite being "skipped".

I believe it's unlikely that tests rely on the current behavior of doing `SKIP` from `SetUp` and running the test anyway. So, I expect this to be a relatively safe change.

Reviewed By: simpkins

Differential Revision: D15703771

fbshipit-source-id: d32e1d9c4cb8cb99c667882b81946154c6ca906b

Summary:
DeterministicSchedule does not work on mobile because __thread or thread_local
support is not present.  folly::ThreadLocal helps because it uses
pthread_getspecific for mobile and platforms where support for this is not there

This does mean that we can't add DSched tests for folly::ThreadLocal, but that
does not have DSched tests anyway.  When we add DSched tests for that, we can
move to using a lock + map keyed by std::this_thread::get_id

Reviewed By: yfeldblum

Differential Revision: D15770455

fbshipit-source-id: 2a3cc6b3b1c116469cce6295a641d784e5bdfd50

Summary: [Folly] Always define `FOLLY_LIBRARY_SANITIZE_ADDRESS` to either 0 or 1.

Reviewed By: simpkins

Differential Revision: D10414836

fbshipit-source-id: d60ef8380c50971858ed282374f1b5973a27cdf4

Summary:
- Cut `#if __GNUC_PREREQ(5, 0)` preprocessor directive as folly does not
  support any GCC version lower than 5.1.
- Change from `FOLLY_GNU_DISABLE_WARNING` to `FOLLY_GCC_DISABLE_WARNING`
  since Clang does not support `-Wbool-compare` option.
Pull Request resolved: https://github.com/facebook/folly/pull/1151

Reviewed By: Orvid

Differential Revision: D15618528

Pulled By: yfeldblum

fbshipit-source-id: 039e0aad617ccb40392505a6f4585e93d52dc81c

Summary:
Fix https://github.com/facebook/folly/issues/1111 by calling
`assign()` directly. All `ExpectedStorage::assign()` implementations
eventually call `doEmplaceAssign()` which uses SFINAE to assign,
and if that fails emplace. Therefore, they only need `std::is_constructible`.

Reviewed By: yfeldblum

Differential Revision: D15756301

fbshipit-source-id: e7759128c13344ed6e3d58d6ea143fd68af8121b

Summary: [Folly] Rename `FOLLY_ASAN_ENABLED` to `FOLLY_LIBRARY_SANITIZE_ADDRESS`.

Reviewed By: simpkins

Differential Revision: D10414837

fbshipit-source-id: b7ca2a36dd7f91ccab2f8051f78c75909f378d16

Summary:
This is a hack for now to allow fbsource-based watchman getdeps builds to
succeed.  In the long run we need to update Watchman's CMakeLists.txt to
depend on a proper EdenFS build, rather than copying Eden's thrift files into
Watchman's source tree.

Reviewed By: wez

Differential Revision: D15753320

fbshipit-source-id: 2dea483c2053c4ea1cf64021c4bbc3239fce645d

Summary: [Folly] Support various operations on empty `IPAddress` and `SocketAddress`, i.e. default-constructed instances, such as `operator==` and `hash`. V.s. throwing exceptions.

Reviewed By: simpkins

Differential Revision: D15750100

fbshipit-source-id: 89853635f6aab3c295f6fca4e66e6435b0839357

Summary:
The previous diffs in the stack add fbcode_builder manifests for FBOSS
dependencies iproute2 and OpenNSL. The other FBOSS dependencies already have
fbcode_builder support. Thus, add FBOSS manifest.

Additionally, this patch also modifies fboss CMakeLists.txt to get FBOSS to
build using fbcode_builder.

Reviewed By: wez

Differential Revision: D15626298

fbshipit-source-id: 31802ef695ae69b08f526bbeb299c59f3b9d44be

Summary:
D15683387 introduced manifest for libcurl and used cmake instead of autoconf
(rationale: having cmake build curl would make it easy as we want curl to build
on windows and macos).

if libcurl finds ldap.h, then it builds with ldap enabled.
On my devserver, ldap library is not installed, and thus libcurl builds without
it, and links with FBOSS binaries fine.

In sandbox, ldap seems to be installed, thus libcurl builds with ldap. However,
linking fails for FBOSS binaries as those don't link against ldap - FBOSS does
not depend on ldap.

Thus, we need a way to configure libcurl with ldap disabled. [cmake.defines]
CURL_DISABLE_LDAP=OFF, does not quite do it. Thus, am going with autoconf, with
args --disable-ldap for now for Linux and cmake for non-Linux environments.

Reviewed By: wez

Differential Revision: D15730947

fbshipit-source-id: 2ce48976ee785401d550720cbdccb22f9d416675

Summary:
D15588809 introduced manifest and customer builder for iproute2. While the
Iproute2Builder copies include/* from build to install directory, it does not
copy lib/* which contains the libnetlink.a

As a result, the build system looks up libnetlink.a on local machine (which it
may not find).

Fix it by explicitly coping lib/* as well.

Reviewed By: wez

Differential Revision: D15708835

fbshipit-source-id: 3f5906eb48ce982b6e887cca0d3c11314425beab

Summary: This diff allows zmq socket to run on folly::fibers

Reviewed By: saifhhasan

Differential Revision: D15113447

fbshipit-source-id: 8a0e1f91d719a9deda48837d4ff1065408280b72

Summary: Build failures with gcc-7 suggest that gcc-7 is not property short-circuiting SFINAE conditions in the parameter list of function templates. Re-express as cascading tests to avoid the hard error.

Reviewed By: yfeldblum

Differential Revision: D15730238

fbshipit-source-id: 793e12630d609d4e135b4a55714be0cb0496f6f7

Summary: Original commit changeset: 5e101fc38417

Reviewed By: snarkmaster

Differential Revision: D15726457

fbshipit-source-id: 001ee9ebaee81ebc60996e5fb95c1870121b2dec

Summary:
[Folly] Fixed constexpr append in `FixedString` tests after {D15618465}.

```
folly/test/FixedStringTest.cpp: In member function 'virtual void FixedStringAssignTest_ConstexprAppendLiteral_Test::TestBody()':
folly/test/FixedStringTest.cpp:360:3: error: non-constant condition for static assertion
   static_assert(constexpr_append_literal_test() == "hello world!", "");
   ^~~~~~~~~~~~~
In file included from folly/Range.h:25:0,
                 from folly/FixedString.h:33,
                 from folly/test/FixedStringTest.cpp:20:
folly/test/FixedStringTest.cpp:360:47:   in constexpr expansion of 'constexpr_append_literal_test()'
folly/test/FixedStringTest.cpp:355:18:   in constexpr expansion of '#'result_decl' not supported by dump_expr#<expression error>.folly::BasicFixedString<char, 20>::append((& s[7]))'
folly/FixedString.h:1277:48:   in constexpr expansion of 'folly::constexpr_strlen<char>(that)'
folly/portability/Constexpr.h:68:21: error: 'strlen((& s[7]))' is not a constant expression
   return std::strlen(s);
          ~~~~~~~~~~~^~~
```

Reviewed By: simpkins

Differential Revision: D15643402

fbshipit-source-id: c7e26a0c37c956300364c566f211c866985d9dc2

Summary:
It's common for people reading the F14 code to
see the fallback implementation without noticing the #if
!FOLLY_F14_VECTOR_INTRINSICS_AVAILABLE at the top, which leads them to
incorrect conclusions about the code. This diff flips the order in the
file to reduce confusion.

Reviewed By: shixiao

Differential Revision: D15571969

fbshipit-source-id: 10d2aa29da3f1b8dd48af490a53f1f845f103fa8

Summary: [Folly] Merge `folly/futures/helpers.h` into `folly/futures/Future.h` to avoid the cyclic include trap.

Differential Revision: D15600550

fbshipit-source-id: a0d14c0092bb433f7af797201d9fafebab370502

Summary: pthread_getname_np() tries to dereference 0 when called with it, let's turn it into an error instead

Reviewed By: yfeldblum

Differential Revision: D15708351

fbshipit-source-id: aa2dd92e12e33174c8998daed056de50d4111774

Summary:
This diff adds an option "level" to standard log handler configuration so handlers can have individual logging level set.

This allows us to have multiple handler that handles messages with different level settings.

For example,

> eden=DBG3:default:other; default=stream; other=stream:level=WARN;

This configuration creates two log handlers "default" and "other". Both of the handlers will be receiving log messages level "DBG3" from "eden" log category. In this example, "other" handler will only be receiving log messages that is >= "WARN" while the "default" handler still receives all messages >= "DBG3".

However, one catch of this diff is that, when the log category is set to a higher logging level and the log handler has a lower logging level. The log handler will NOT receive any log messages that is lower than the log category logging level. The test `LogLevelReverseTest` illustrate this situation.

Reviewed By: simpkins

Differential Revision: D15541101

fbshipit-source-id: 741aa97d2d5e93c40324bf6a3dd1d9e38f4dc6a5

Change SharedInfoObserverEntryBase::beforeFreeExtBuffer to SharedInfoObserverEntryBase::afterFreeExtBuffer

Summary: Change SharedInfoObserverEntryBase::beforeFreeExtBuffer to SharedInfoObserverEntryBase::afterFreeExtBuffer

Reviewed By: yfeldblum

Differential Revision: D15687084

fbshipit-source-id: 8f77a123f1bdc0e0ee7391dee7da47d9b9addc6d

Summary:
This is towards getting open source FBOSS to build using fbcode_builder.
libnl is one of the dependencies for FBOSS. This patch adds a manifest
file to build libnl.

Reviewed By: wez

Differential Revision: D15686853

fbshipit-source-id: f7549df6dc1005630193b024be6e1ea330cc6646

Summary:
This is towards getting open source FBOSS to build using fbcode_builder.
libcurl is one of the dependencies for FBOSS. This patch adds a manifest
file to build libcurl.

Reviewed By: wez

Differential Revision: D15683387

fbshipit-source-id: 8df5c413e7dff06d1a19e0ce3b1706bff2f1ab54

Summary:
This is towards getting open source FBOSS to build using fbcode_builder.
libusb is one of the dependencies for FBOSS. This patch adds a manifest
file to build libusb. FBOSS does not need libudev, so we avoid unncessary
dependency by passing right argument to ./configure.

Reviewed By: wez

Differential Revision: D15683386

fbshipit-source-id: 1d35caecf4012ddc0df24a7305019d522b4763fa

Summary: If fiber was activated with an exception it's safe for that fiber to be preempted.

Differential Revision: D15640534

fbshipit-source-id: d908aacd81e1ec57874324a58b180587a1fe2eeb

Summary: Replace inclusions of `folly/futures/helpers.h` with `folly/futures/Future.h` to avoid the cyclic include trap.

Differential Revision: D15600549

fbshipit-source-id: 19950be24a7437fb1fbec293e24058adf17343ca

Summary:
We sometimes see some flakeyness in our internal CI, so we can live
without it there.

Reviewed By: pkaush

Differential Revision: D15695124

fbshipit-source-id: 1d76ae89e245d9c95937e8818826c544c0ae8fc3

Summary:
Currently, AsyncSocket's `connect` API creates new socket, set various
options, bind it to passed argument address and used it for connecting to
server.

While most of the things are handled inside that single connect routine; sometimes
if the caller would like to do few more additional operations before actual
connect happens; caller would like to have hold on the underneath used socket.

In order to do that additional operation on the socket, this diff provides the
facility to provide custom pre-connect hook `preConnect(NetworkSocket fd)` in
the `ConnectCallback` which will be invoked just before the actual server
connect.

Reviewed By: yfeldblum

Differential Revision: D15282727

fbshipit-source-id: 5beac55c77a9537ee4f26856dd5f78c5224a1f49

Summary: Input and output types for the cast are the same (except const qualifier) and therefore it's not required.

Reviewed By: milend

Differential Revision: D15694981

fbshipit-source-id: d5a811d97cc145ba9c232b79f6c8fa52041b0cf0

Summary:
[Folly] `XLOG_EVERY_N_THREAD`.

Implemented with a single per-thread map for all `XLOG_EVERY_N_THREAD` collectively. This approach has better TLS overhad than a `thread_local` counter per `XLOG_EVERY_N_THREAD`, at the cost of integer-keyed map lookups.

While the `thread_local` counter approach is twice as fast as this approach for a noop log-handler, it is expected that the runtime overhead of real log-handlers will make this type of saving immaterial.

Reviewed By: simpkins, luciang

Differential Revision: D15293529

fbshipit-source-id: 7af535a0d329473126a0e4dcffc19d750e8b8b10

Summary:
Lifo sem exposes allocateNode and tryWaitOrPush as protected which allows inherited classes custom Node implementation, creation and enqueueing.
tryRemoveNode was private which prevented inherited classes from dequeueing a Node without signaling shutdown.
This diff fixes it

Reviewed By: shixiao

Differential Revision: D15647287

fbshipit-source-id: 5b26a9616f6de559224f9d8c38230780c78a7cf5

Summary: [Folly] Let `KeepAlive::copy()` allow dummy executors to expire, and not attempt to dereference them to perform an acquire - which, as is known in advance, would fail and return false were the executor still to be alive.

Reviewed By: andrewcox

Differential Revision: D15683240

fbshipit-source-id: e2026493af6936b8f0f1b8fe3c1cb97d2bf0f96e

Summary: [Folly] Split KeepAlive concepts of dummy and alias. A dummy KeepAlive is one for an executor which does not actually support keep-alive semantics. An alias KeepAlive is one for which there is another KeepAlive, with a surrounding lifetime, to the same executor.

Reviewed By: andrewcox

Differential Revision: D15683241

fbshipit-source-id: a5809b06c90ed4a655a6973fac67137b5e1981dc

Summary:
[Folly] Avoid gcc7 lambda-captures bug in `SerialExecutor` test.

```
folly/executors/test/SerialExecutorTest.cpp: In lambda function:
folly/executors/test/SerialExecutorTest.cpp:66:40: error: declaration of 'i' shadows a previous local [-Werror=shadow]
folly/executors/test/SerialExecutorTest.cpp:60:12: note: shadowed declaration is here
folly/executors/test/SerialExecutorTest.cpp: In function 'void simpleTest(const std::shared_ptr<folly::Executor>&)':
folly/executors/test/SerialExecutorTest.cpp:74:45: error: already captured 'i' in lambda expression [-Werror]
folly/executors/test/SerialExecutorTest.cpp: In lambda function:
folly/executors/test/SerialExecutorTest.cpp:74:62: error: 'i' is not captured
folly/executors/test/SerialExecutorTest.cpp:74:46: note: the lambda has no capture-default
folly/executors/test/SerialExecutorTest.cpp:60:12: note: 'int i' declared here
```

Fixes #1154.

Reviewed By: andriigrynenko

Differential Revision: D15629657

fbshipit-source-id: fec82e9d54b2c79a7f54f366ec8a19ad7dc198e9

Summary:
- Cut `FOLLY_HAVE_COMPARE_EQUIVALENT` as this is `1` for Clang 3.4
  onward (regardless of `libstdc++` or `libc++`) and also `1` for GCC
  versions we support.
Pull Request resolved: https://github.com/facebook/folly/pull/1157

Reviewed By: Orvid

Differential Revision: D15641688

Pulled By: yfeldblum

fbshipit-source-id: 0602913b375a406cce6337e43ba708362a94d444

Summary:
This is towards getting open source FBOSS to build using fbcode_builder.
libmnl is one of the dependencies for FBOSS. This patch adds a manifest file
to build the specific version of libmnl for FBOSS.

Reviewed By: wez

Differential Revision: D15633176

fbshipit-source-id: dd51997ae950f53842711fbf2d044e84cdf437e7

Summary:
This is towards getting open source FBOSS to build using fbcode_builder.
OpenNSL is one of the dependencies for FBOSS.

OpenNSL is github repository with headers and prebuilt opaque library. Thus, we
can't/don't need to build it. Thus, OpenNSL manifest uses NopBuilder.

fbcode_builder expects the library to be in installed/lib and headers to be in
installed/include, but OpenNSL lib structure is different.  Thus, add explicit
[install.fields] rule for bin/wedge => lib. Once a rule(s) is provided, we must
provide rule(s) for all, so add rule for include => include as well.

Reviewed By: wez

Differential Revision: D15593639

fbshipit-source-id: facb36ff7b9a31f5952ecbc1a9fdb834c0e68d11

Summary:
This is towards getting open source FBOSS to build using fbcode_builder.
iproute2 is one of the dependencies for FBOSS. This patch adds a manifest file
to build the specific version of iproute2 needed for FBOSS.

Additionally, the default git clone depth of 100 is insufficient for the
version of iproute2 FBOSS depends on. Thus, this patch extends the git SCHEMA
to add optional argument depth. The default remains 100.

The usual /configure --prefix does not work for iproute2. Thus, we need to add
a custom builder that:
  - copies sources to build directory, builds, and
  - installs to installed directory using DEST_DIR.
  - it must also explicitly copy include from build dir to install dir

Reviewed By: wez

Differential Revision: D15588809

fbshipit-source-id: ac5eab24134e078d88b85b4be433c78b05ef8ce5