* Refactoring of PerfCounters infrastructure
The main feature in this pull request is the removal of the static
sharing of PerfCounters and instead creating them at the top
`RunBenchmarks()` function where all benchmark runners are created. A
single PerfCountersMeasurement object is created and then shared with
all the new BenchmarkRunners objects, one per existing benchmark.
Other features conflated here in this PR are:
- Added BENCHMARK_DONT_OPTIMIZE macro in global scope
- Removal of the `IsValid()` query, being replaced by checking the
number of remaining counters after validity tests
- Refactoring of all GTests to reflect the changes and new semantics
- extra comments throughout the new code to clarify intent
It was extremely hard to separate all those features in different PRs
as requested since they are so interdependent on each other so I'm just
pushing them altogether and asking for forgiveness.
This PR comes replacing PRs 1555 and 1558 which have been closed.
* Fixed whitespace issue with clang-format
My clang-format insists in deleting this single white space on line 601
while Github's clang format breaks when it is added. I had to disable
format-on-save to check-in this revert change.
I'm using clang 14.0.6.
* Filter performance counter names, not invalidate all
Currently, the performance counters are validated while they
are being created and one failure returns NoCounters(), ie it
effecitvely invalidates all the counters.
I would like to propose a new behavior: filter instead. If an
invalid name is added to the counter list, or if that particular
counter is not supported on this platform, that counter is dropped
from the list and an error messages is created, while all the
other counters remain active.
This will give testers a peace of mind that if one mistake is made
or if something is changed or removed from libpfm, their entire
test will not be invalidated. This feature gives more tolerance
with respect to versioning.
Another positive is that testers can now input a superset of all
desired counters for all platforms they support and just let
Benchmark drop all those that are not supported, although it will
create quite a lot of noise down the line, in which case perhaps
we should drop silently or make a consolidated, single error line
but this was not implemented in this change set.
* Removed unused helper type.
* Implement unlimited number of performance counters
Linux performance counters will limit the number of hardware
counters per reading group. For that reason the implementation of
PerfCounters is limited to 3. However if only software counters
are added, there is no reason to limit the counters. For hardware
counters, we create multiple groups and store a vector or leaders
in the PerfCounters object. When reading, there is an extra time
waste by iterating through all the group leaders. However this
should be the same performance as with today. Reading is done by
groups and it had to be heavily adjusted with the logic being
moved to PerfCounterValues. I created a test for x86-64 and took
care of filtering out the events in case it runs in a platform
that does not support those counters - the test will not fail. The
current tests were already failing (ReOpenExistingCounters,
CreateExistingMeasurements and MultiThreaded) on the main branch
and they continue to fail after this implementation - I did not
fix those not to conflate all here.
* Moved the PerfCounterValues::Read() implementation from header to body.
* Added missing implementation of PerfCounters::IsCounterSupported when HAVE_LIBPFM is not defined.
* Changed comments to reflect the implementation
* Removed arg name so it does not generate an error when HAVE_LIBPBM is not defined.
* Made loop counter a const reference for clang-tidy
* Added missig BENCHMARK_EXPORT to PerfCounterValues
* Allow specifying number of iterations via --benchmark_min_time.
Make the flag accept two new suffixes:
+ <integer>x: number of iterations
+ <floag>s: minimum number of seconds.
This matches the internal benchmark API.
* forgot to change flag type to string
* used tagged union instead of std::variant, which is not available pre C++14
* update decl in benchmark_runner.h too
* fixed errors
* refactor
* backward compat
* typo
* use IterationCount type
* fixed test
* const_cast
* ret type
* remove extra _
* debug
* fixed bug from reporting that caused the new configs not to be included in the final report
* addressed review comments
* restore unnecessary changes in test/BUILD
* fix float comparisons warnings from Release builds
* clang format
* fix visibility warning
* remove misc file
* removed backup files
* addressed review comments
* fix shorten in warning
* use suffix for existing min_time specs to silent warnings in tests
* fix leaks
* use default min-time value in flag decl for consistency
* removed double kMinTimeDecl from benchmark.h
* dont need to preserve errno
* add death tests
* Add BENCHMARK_EXPORT to hopefully fix missing def errors
* only enable death tests in debug mode because bm_check is no-op in release mode
* guard death tests with additional support-check macros
* Add additional guard to prevent running in Release mode
---------
Co-authored-by: dominic <510002+dmah42@users.noreply.github.com>
* fix#1446 by removing the address operator
* add test
* format
---------
Co-authored-by: Thomas <thomas.maierbacher@rohde-schwarz.com>
Co-authored-by: Dominic Hamon <dominichamon@users.noreply.github.com>
* Include the benchmark's family-name in State
For compat with internal library, where State::name() returns the benchmark's family name.
* added missing files from prev commit
* fix field-init order error
* added test
* Bug fix variable 'actual_iterations' set but not used
Compiling the project in clang 15 without -Wno-unused-but-set-variable flag the following error is generated:
benchmark-src/test/options_test.cc:70:10: error: variable 'actual_iterations' set but not used [-Werror,-Wunused-but-set-variable]
size_t actual_iterations = 0;
^
* Adjust according formatting of `clang-format`
Co-authored-by: dominic hamon <510002+dmah42@users.noreply.github.com>
Some linux distributions no longer provide `python` binary and require
usage of `python3` instead. This changes the scripts here and uses
cmake `find_package(Python3` when running python.
Co-authored-by: Dominic Hamon <dominichamon@users.noreply.github.com>
This patch fixes compilation on Solaris, addressing the problems reported
in Issue #1499:
* Provide `HOST_NAME_MAX` definition.
* Match `sysconf(3C)` return type.
* Avoid `-Wcast-qual` warnings with `libkstat(3KSTAT)` functions.
* Avoid clash with `<floatingpoint.h>` `single` typedef.
* Ensure we don't need benchmark installed to pass c++ feature checks
Requires removal of some dependencies on benchmark.h from internal
low-level headers, which is a good thing.
Also added better logging to the feature check cmake module.
* Explicitly cast int literals to int8_t in tests so silence implicit-conversion warnings
Error came from:
```
: error: implicit conversion loses integer precision: 'const int' to 'const signed char' [-Werror,-Wimplicit-int-conversion]
```
* clang format
* undo deleted line
* Fixed build issues on window
- Added missing dlimport/export attributes in function definitions. (They are needed in both decls and defs)
- Removed dlimport/dlexprt attribute in private field. (global_context is not exported anywhere).
* fixed incorrect include path
* undo changes w.r.t HelperPrintf
* removed forward decl of private variable - instead, introduce a getter and use it.
* Removed forward decl from benchmark_gtest too
Co-authored-by: Dominic Hamon <dominichamon@users.noreply.github.com>
* Stop generating the export header and just check it in
* format the new header
* support windows
* format the header again
* avoid depending on internal macro
* ensure we define the right thing for windows static builds
* support older cmake
* and for tests
Non-const DoNotOptimize() can't compile when used with some types.
Example of code which can't compile:
char buffer3[3] = "";
benchmark::DoNotOptimize(buffer3);
Error message:
error: impossible constraint in 'asm'
asm volatile("" : "+r"(value) : : "memory");
Introduced in 8545dfb (Fix DoNotOptimize() GCC copy overhead (#1340) (#1410))
The cause is compiler can't work with the +r constraint for types that can't
be placed perfectly in registers. For example, char array[3] can't be perfectly
fit in register on x86_64 so it requires placed in memory but constraint
doesn't allow that.
Solution
- Use +m,r constraint for the small objects so the compiler can decide to use
register or/and memory
- For the big objects +m constraint is used which allows avoiding extra copy
bug(see #1340)
- The same approach is used for the const version of DoNotOptimize()
although the const version works fine with the "r" constraint only.
Using mixed r,m constraint looks more general solution.
See
- Issue #1340 ([BUG] DoNotOptimize() adds overhead with extra copy of argument(gcc))
- Pull request #1410 (Fix DoNotOptimize() GCC copy overhead (#1340) #1410)
- Commit 8545dfb (Fix DoNotOptimize() GCC copy overhead (#1340) (#1410))
* Fix DoNotOptimize() GCC copy overhead (#1340)
The issue is that GCC DoNotOptimize() does a full copy of an argument
if it's not a pointer and it slows down a benchmark. If an argument is big
enough there is a memcpy() call for copying the argument. An argument
object can be a big object so DoNotOptimize() could add sufficient
overhead and affects benchmark results.
The cause is in GCC behavior with asm volatile constraints. Looks like GCC
trying to use r(register) constraint for all cases despite object size.
See: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105519
The solution is the split DoNotOptimize() in two cases - value fits
in register and value doesn't fit in register. And use case specific
asm constraint. std::is_trivially_copyable trait is needed because
"+r" constraint doesn't work with non trivial copyable objects.
- Fix requires support C++11 feature std::is_trivially_copyable from GCC
compiler. The feature has been supported since GCC 5
- Fallback for GCC version < 5 still exists but it uses "m" constraint
which means a little bit more overhead in some cases
- Add assembly tests for issued cases
Fixes#1340
* Add supported compiler versions info for assembly tests
- Assembly tests are inherently non-portable. So explicitly add GCC
and Clang versions required for reliable tests passed
- Write a warning message if the current compiler version isn't supported
* Add possibility to ask for libbenchmark version number (#1004)
Add a header which holds the current major, minor, and
patch number of the library. The header is auto generated
by CMake.
* Do not generate unused functions (#1004)
* Add support for version number in bazel (#1004)
* Fix clang format #1004
* Fix more clang format problems (#1004)
* Use git version feature of cmake to determine current lib version
* Rename version_config header to version
* Bake git version into bazel build
* Use same input config header as in cmake for version.h
* Adapt the releasing.md to include versioning in bazel
* add multiple OSes to bazel workflow
* correct indent
* only set copts when they're supported by the OS
* os check should work
* pull out cxx03_test for per-platform stuff
* attempt to fix windows test output
* Introduce warmup phase to BenchmarkRunner (#1130)
In order to account for caching effects in user
benchmarks introduce a new command line option
"--benchmark_min_warmup_time"
which allows to specify an amount of time for
which the benchmark should be run before results
are meaningful.
* Adapt review suggestions regarding introduction of warmup phase (#1130)
* Fix BM_CHECK call in MinWarmUpTime (#1130)
* Fix comment on requirements of MinWarmUpTime (#1130)
* Add basic description of warmup phase mechanism to user guide (#1130)
* Add option to get the verbosity provided by commandline flag -v (#1330)
* replace assert with test failure
asserts are stripped out in non debug builds, and we run tests in non-debug CI bots.
* clang-format my own tweak
Co-authored-by: Dominic Hamon <dominichamon@users.noreply.github.com>
* Filter out benchmarks that start with "DISABLED_"
This could be slightly more elegant, in that the registration and the
benchmark definition names have to change. Ideally, we'd still register
without the DISABLED_ prefix and it would all "just work".
Fixes#1365
* add some documentation
* Add SetBenchmarkFilter() to set --benchmark_filter flag value in user code.
Use case: Provide an API to set this flag indepedence of the flag's implementation (ie., absl flag vs benchmark's flag facility)
* add test
* added notes on Initialize()
* Add option to set the default time unit globally
This commit introduces the `--benchmark_time_unit={ns|us|ms|s}` command line argument. The argument only affects benchmarks where the time unit is not set explicitly.
* Update AUTHORS and CONTRIBUTORS
* Test `SetDefaultTimeUnit`
* clang format
* Use `GetDefaultTimeUnit()` for initializing `TimeUnit` variables
* Review fixes
* Export functions
* Add comment
* Expose default display reporter creation in public API
this is useful when a custom reporter wants to fall back on the default
display reporter, but doesn't necessarily have access to the benchmark
library flag configuration.
* Make use of unique_ptr in the random interleaving test.
* clang-format
* The parameterized tests check both floating point and integral types. We might as well use types that avoid truncation warnings across the platforms
* static_cast version of how to avoid truncation warnings in basic_test
Co-authored-by: Staffan Tjernstrom <staffantj@users.noreply.github.com>
This patch fixes#1306, by reducing the pinned instances of
PerfCounters.
The issue is caused by creating multiple pinned events in the
same thread, doing so results in the Snapshot(PerfCounterValues* values)
failing, and that's now discoverable.
Creating multile pinned events is an unsupported behavior currently.
The error would be detected at read() time, not
perf_event_open() / iotcl() time.
The unsupported benavior above is confirmed by Stephane Eranian @seranian,
and he also pointed the dectection method.
Finished this patch under the guidance of Mircea Trofin @mtrofin.
* Add Setup/Teardown option on Benchmark.
Motivations:
- feature parity with our internal library. (which has ~718 callers)
- more flexible than cordinating setup/teardown inside the benchmark routine.
* change Setup/Teardown callback type to raw function pointers
* add test file to cmake file
* move b.Teardown() up
* add const to param of Setup/Teardown callbacks
* fix comment and add doc to user_guide
* fix typo
* fix doc, fix test and add bindings to python/benchmark.cc
* fix binding again
* remove explicit C cast - that was wrong
* change policy to reference_internal
* try removing the bindinds ...
* clean up
* add more tests with repetitions and fixtures
* more comments
* init setup/teardown callbacks to NULL
* s/nullptr/NULL
* removed unused var
* change assertion on fixture_interaction::fixture_setup
* move NULL init to .cc file
* Fix un-initted error in test.
Found by -Werror,-Wsometimes-uninitialized
* Update spec_arg_test.cc
* additional change:
- Change the API on GetBenchmarkFilter and the `spec` to std::string because google C++ styleguide internally kind of discouraged using raw const char*
* [RFC] Adding API for setting/getting benchmark_filter flag?
This PR is more of a Request-for-comment - open to other ideas/suggestions as well.
Details:
This flag has different implementations(absl vs benchmark) and since the proposal to add absl as a dependency was rejected, it would be nice to have a reliable (and less hacky) way to access this flag internally.
(Actually, reading it isn't much a problem but setting it is).
Internally, we have a sizeable number users to use absl::SetFlags to set this flag. This will not work with benchmark-flags.
Another motivation is that not all users use the command line flag. Some prefer to programmatically set this value.
* fixed build errors
* fix lints again
* per discussion: add additional RunSpecifiedBenchmarks instead.
* add tests
* fix up tests
* clarify comment
* fix stray : in test
* more assertion in test
* add test file to test/CMakeLists.txt
* more test
* make test ISO C++ compliant
* fix up BUILD file to pass the flag
* Allow template arguments to be specifed directly on the BENCHMARK macro/
Use cases:
- more convenient (than having to use a separate BENCHMARK_TEMPLATE)
- feature parity with our internal library.
* fix tests
* updated docs
In #1238, one of MemoryManager's Stop methods was marked as deprecated
and this method is used in the same header. This change generated
-Wdeprecated-declarations warning on every file that includes
"benchmark.h". Use gcc's diagnostics to fix this warning.
Henrique Bucher