tbb_misc_ex.cpp
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/*
Copyright (c) 2005-2020 Intel Corporation
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
// Source file for miscellaneous entities that are infrequently referenced by
// an executing program, and implementation of which requires dynamic linking.
#include "tbb_misc.h"
#if !defined(__TBB_HardwareConcurrency)
#include "dynamic_link.h"
#include <stdio.h>
#include <limits.h>
#if _WIN32||_WIN64
#include "tbb/machine/windows_api.h"
#if __TBB_WIN8UI_SUPPORT
#include <thread>
#endif
#else
#include <unistd.h>
#if __linux__
#include <sys/sysinfo.h>
#include <string.h>
#include <sched.h>
#include <errno.h>
#elif __sun
#include <sys/sysinfo.h>
#elif __FreeBSD__
#include <errno.h>
#include <string.h>
#include <sys/param.h> // Required by <sys/cpuset.h>
#include <sys/cpuset.h>
#endif
#endif
namespace tbb {
namespace internal {
#if __TBB_USE_OS_AFFINITY_SYSCALL
#if __linux__
// Handlers for interoperation with libiomp
static int (*libiomp_try_restoring_original_mask)();
// Table for mapping to libiomp entry points
static const dynamic_link_descriptor iompLinkTable[] = {
DLD_NOWEAK( kmp_set_thread_affinity_mask_initial, libiomp_try_restoring_original_mask )
};
#endif
static void set_thread_affinity_mask( size_t maskSize, const basic_mask_t* threadMask ) {
#if __linux__
if( sched_setaffinity( 0, maskSize, threadMask ) )
#else /* FreeBSD */
if( cpuset_setaffinity( CPU_LEVEL_WHICH, CPU_WHICH_TID, -1, maskSize, threadMask ) )
#endif
runtime_warning( "setaffinity syscall failed" );
}
static void get_thread_affinity_mask( size_t maskSize, basic_mask_t* threadMask ) {
#if __linux__
if( sched_getaffinity( 0, maskSize, threadMask ) )
#else /* FreeBSD */
if( cpuset_getaffinity( CPU_LEVEL_WHICH, CPU_WHICH_TID, -1, maskSize, threadMask ) )
#endif
runtime_warning( "getaffinity syscall failed" );
}
static basic_mask_t* process_mask;
static int num_masks;
void destroy_process_mask() {
if( process_mask ) {
delete [] process_mask;
}
}
#define curMaskSize sizeof(basic_mask_t) * num_masks
affinity_helper::~affinity_helper() {
if( threadMask ) {
if( is_changed ) {
set_thread_affinity_mask( curMaskSize, threadMask );
}
delete [] threadMask;
}
}
void affinity_helper::protect_affinity_mask( bool restore_process_mask ) {
if( threadMask == NULL && num_masks ) { // TODO: assert num_masks validity?
threadMask = new basic_mask_t [num_masks];
memset( threadMask, 0, curMaskSize );
get_thread_affinity_mask( curMaskSize, threadMask );
if( restore_process_mask ) {
__TBB_ASSERT( process_mask, "A process mask is requested but not yet stored" );
is_changed = memcmp( process_mask, threadMask, curMaskSize );
if( is_changed )
set_thread_affinity_mask( curMaskSize, process_mask );
} else {
// Assume that the mask will be changed by the caller.
is_changed = 1;
}
}
}
void affinity_helper::dismiss() {
if( threadMask ) {
delete [] threadMask;
threadMask = NULL;
}
is_changed = 0;
}
#undef curMaskSize
static atomic<do_once_state> hardware_concurrency_info;
static int theNumProcs;
static void initialize_hardware_concurrency_info () {
int err;
int availableProcs = 0;
int numMasks = 1;
#if __linux__
#if __TBB_MAIN_THREAD_AFFINITY_BROKEN
int maxProcs = INT_MAX; // To check the entire mask.
int pid = 0; // Get the mask of the calling thread.
#else
int maxProcs = sysconf(_SC_NPROCESSORS_ONLN);
int pid = getpid();
#endif
#else /* FreeBSD >= 7.1 */
int maxProcs = sysconf(_SC_NPROCESSORS_ONLN);
#endif
basic_mask_t* processMask;
const size_t BasicMaskSize = sizeof(basic_mask_t);
for (;;) {
const int curMaskSize = BasicMaskSize * numMasks;
processMask = new basic_mask_t[numMasks];
memset( processMask, 0, curMaskSize );
#if __linux__
err = sched_getaffinity( pid, curMaskSize, processMask );
if ( !err || errno != EINVAL || curMaskSize * CHAR_BIT >= 256 * 1024 )
break;
#else /* FreeBSD >= 7.1 */
// CPU_LEVEL_WHICH - anonymous (current) mask, CPU_LEVEL_CPUSET - assigned mask
#if __TBB_MAIN_THREAD_AFFINITY_BROKEN
err = cpuset_getaffinity( CPU_LEVEL_WHICH, CPU_WHICH_TID, -1, curMaskSize, processMask );
#else
err = cpuset_getaffinity( CPU_LEVEL_WHICH, CPU_WHICH_PID, -1, curMaskSize, processMask );
#endif
if ( !err || errno != ERANGE || curMaskSize * CHAR_BIT >= 16 * 1024 )
break;
#endif /* FreeBSD >= 7.1 */
delete[] processMask;
numMasks <<= 1;
}
if ( !err ) {
// We have found the mask size and captured the process affinity mask into processMask.
num_masks = numMasks; // do here because it's needed for affinity_helper to work
#if __linux__
// For better coexistence with libiomp which might have changed the mask already,
// check for its presence and ask it to restore the mask.
dynamic_link_handle libhandle;
if ( dynamic_link( "libiomp5.so", iompLinkTable, 1, &libhandle, DYNAMIC_LINK_GLOBAL ) ) {
// We have found the symbol provided by libiomp5 for restoring original thread affinity.
affinity_helper affhelp;
affhelp.protect_affinity_mask( /*restore_process_mask=*/false );
if ( libiomp_try_restoring_original_mask()==0 ) {
// Now we have the right mask to capture, restored by libiomp.
const int curMaskSize = BasicMaskSize * numMasks;
memset( processMask, 0, curMaskSize );
get_thread_affinity_mask( curMaskSize, processMask );
} else
affhelp.dismiss(); // thread mask has not changed
dynamic_unlink( libhandle );
// Destructor of affinity_helper restores the thread mask (unless dismissed).
}
#endif
for ( int m = 0; availableProcs < maxProcs && m < numMasks; ++m ) {
for ( size_t i = 0; (availableProcs < maxProcs) && (i < BasicMaskSize * CHAR_BIT); ++i ) {
if ( CPU_ISSET( i, processMask + m ) )
++availableProcs;
}
}
process_mask = processMask;
}
else {
// Failed to get the process affinity mask; assume the whole machine can be used.
availableProcs = (maxProcs == INT_MAX) ? sysconf(_SC_NPROCESSORS_ONLN) : maxProcs;
delete[] processMask;
}
theNumProcs = availableProcs > 0 ? availableProcs : 1; // Fail safety strap
__TBB_ASSERT( theNumProcs <= sysconf(_SC_NPROCESSORS_ONLN), NULL );
}
int AvailableHwConcurrency() {
atomic_do_once( &initialize_hardware_concurrency_info, hardware_concurrency_info );
return theNumProcs;
}
/* End of __TBB_USE_OS_AFFINITY_SYSCALL implementation */
#elif __ANDROID__
// Work-around for Android that reads the correct number of available CPUs since system calls are unreliable.
// Format of "present" file is: ([<int>-<int>|<int>],)+
int AvailableHwConcurrency() {
FILE *fp = fopen("/sys/devices/system/cpu/present", "r");
if (fp == NULL) return 1;
int num_args, lower, upper, num_cpus=0;
while ((num_args = fscanf(fp, "%u-%u", &lower, &upper)) != EOF) {
switch(num_args) {
case 2: num_cpus += upper - lower + 1; break;
case 1: num_cpus += 1; break;
}
fscanf(fp, ",");
}
return (num_cpus > 0) ? num_cpus : 1;
}
#elif defined(_SC_NPROCESSORS_ONLN)
int AvailableHwConcurrency() {
int n = sysconf(_SC_NPROCESSORS_ONLN);
return (n > 0) ? n : 1;
}
#elif _WIN32||_WIN64
static atomic<do_once_state> hardware_concurrency_info;
static const WORD TBB_ALL_PROCESSOR_GROUPS = 0xffff;
// Statically allocate an array for processor group information.
// Windows 7 supports maximum 4 groups, but let's look ahead a little.
static const WORD MaxProcessorGroups = 64;
struct ProcessorGroupInfo {
DWORD_PTR mask;
int numProcs;
int numProcsRunningTotal;
static int NumGroups;
static int HoleIndex;
};
int ProcessorGroupInfo::NumGroups = 1;
int ProcessorGroupInfo::HoleIndex = 0;
ProcessorGroupInfo theProcessorGroups[MaxProcessorGroups];
struct TBB_GROUP_AFFINITY {
DWORD_PTR Mask;
WORD Group;
WORD Reserved[3];
};
static DWORD (WINAPI *TBB_GetActiveProcessorCount)( WORD groupIndex ) = NULL;
static WORD (WINAPI *TBB_GetActiveProcessorGroupCount)() = NULL;
static BOOL (WINAPI *TBB_SetThreadGroupAffinity)( HANDLE hThread,
const TBB_GROUP_AFFINITY* newAff, TBB_GROUP_AFFINITY *prevAff );
static BOOL (WINAPI *TBB_GetThreadGroupAffinity)( HANDLE hThread, TBB_GROUP_AFFINITY* );
static const dynamic_link_descriptor ProcessorGroupsApiLinkTable[] = {
DLD(GetActiveProcessorCount, TBB_GetActiveProcessorCount)
, DLD(GetActiveProcessorGroupCount, TBB_GetActiveProcessorGroupCount)
, DLD(SetThreadGroupAffinity, TBB_SetThreadGroupAffinity)
, DLD(GetThreadGroupAffinity, TBB_GetThreadGroupAffinity)
};
static void initialize_hardware_concurrency_info () {
#if __TBB_WIN8UI_SUPPORT
// For these applications processor groups info is unavailable
// Setting up a number of processors for one processor group
theProcessorGroups[0].numProcs = theProcessorGroups[0].numProcsRunningTotal = std::thread::hardware_concurrency();
#else /* __TBB_WIN8UI_SUPPORT */
dynamic_link( "Kernel32.dll", ProcessorGroupsApiLinkTable,
sizeof(ProcessorGroupsApiLinkTable)/sizeof(dynamic_link_descriptor) );
SYSTEM_INFO si;
GetNativeSystemInfo(&si);
DWORD_PTR pam, sam, m = 1;
GetProcessAffinityMask( GetCurrentProcess(), &pam, &sam );
int nproc = 0;
for ( size_t i = 0; i < sizeof(DWORD_PTR) * CHAR_BIT; ++i, m <<= 1 ) {
if ( pam & m )
++nproc;
}
__TBB_ASSERT( nproc <= (int)si.dwNumberOfProcessors, NULL );
// By default setting up a number of processors for one processor group
theProcessorGroups[0].numProcs = theProcessorGroups[0].numProcsRunningTotal = nproc;
// Setting up processor groups in case the process does not restrict affinity mask and more than one processor group is present
if ( nproc == (int)si.dwNumberOfProcessors && TBB_GetActiveProcessorCount ) {
// The process does not have restricting affinity mask and multiple processor groups are possible
ProcessorGroupInfo::NumGroups = (int)TBB_GetActiveProcessorGroupCount();
__TBB_ASSERT( ProcessorGroupInfo::NumGroups <= MaxProcessorGroups, NULL );
// Fail safety bootstrap. Release versions will limit available concurrency
// level, while debug ones would assert.
if ( ProcessorGroupInfo::NumGroups > MaxProcessorGroups )
ProcessorGroupInfo::NumGroups = MaxProcessorGroups;
if ( ProcessorGroupInfo::NumGroups > 1 ) {
TBB_GROUP_AFFINITY ga;
if ( TBB_GetThreadGroupAffinity( GetCurrentThread(), &ga ) )
ProcessorGroupInfo::HoleIndex = ga.Group;
int nprocs = 0;
for ( WORD i = 0; i < ProcessorGroupInfo::NumGroups; ++i ) {
ProcessorGroupInfo &pgi = theProcessorGroups[i];
pgi.numProcs = (int)TBB_GetActiveProcessorCount(i);
__TBB_ASSERT( pgi.numProcs <= (int)sizeof(DWORD_PTR) * CHAR_BIT, NULL );
pgi.mask = pgi.numProcs == sizeof(DWORD_PTR) * CHAR_BIT ? ~(DWORD_PTR)0 : (DWORD_PTR(1) << pgi.numProcs) - 1;
pgi.numProcsRunningTotal = nprocs += pgi.numProcs;
}
__TBB_ASSERT( nprocs == (int)TBB_GetActiveProcessorCount( TBB_ALL_PROCESSOR_GROUPS ), NULL );
}
}
#endif /* __TBB_WIN8UI_SUPPORT */
PrintExtraVersionInfo("Processor groups", "%d", ProcessorGroupInfo::NumGroups);
if (ProcessorGroupInfo::NumGroups>1)
for (int i=0; i<ProcessorGroupInfo::NumGroups; ++i)
PrintExtraVersionInfo( "----- Group", "%d: size %d", i, theProcessorGroups[i].numProcs);
}
int NumberOfProcessorGroups() {
__TBB_ASSERT( hardware_concurrency_info == initialization_complete, "NumberOfProcessorGroups is used before AvailableHwConcurrency" );
return ProcessorGroupInfo::NumGroups;
}
// Offset for the slot reserved for the first master thread
#define HoleAdjusted(procIdx, grpIdx) (procIdx + (holeIdx <= grpIdx))
int FindProcessorGroupIndex ( int procIdx ) {
// In case of oversubscription spread extra workers in a round robin manner
int holeIdx;
const int numProcs = theProcessorGroups[ProcessorGroupInfo::NumGroups - 1].numProcsRunningTotal;
if ( procIdx >= numProcs - 1 ) {
holeIdx = INT_MAX;
procIdx = (procIdx - numProcs + 1) % numProcs;
}
else
holeIdx = ProcessorGroupInfo::HoleIndex;
__TBB_ASSERT( hardware_concurrency_info == initialization_complete, "FindProcessorGroupIndex is used before AvailableHwConcurrency" );
// Approximate the likely group index assuming all groups are of the same size
int i = procIdx / theProcessorGroups[0].numProcs;
// Make sure the approximation is a valid group index
if (i >= ProcessorGroupInfo::NumGroups) i = ProcessorGroupInfo::NumGroups-1;
// Now adjust the approximation up or down
if ( theProcessorGroups[i].numProcsRunningTotal > HoleAdjusted(procIdx, i) ) {
while ( theProcessorGroups[i].numProcsRunningTotal - theProcessorGroups[i].numProcs > HoleAdjusted(procIdx, i) ) {
__TBB_ASSERT( i > 0, NULL );
--i;
}
}
else {
do {
++i;
} while ( theProcessorGroups[i].numProcsRunningTotal <= HoleAdjusted(procIdx, i) );
}
__TBB_ASSERT( i < ProcessorGroupInfo::NumGroups, NULL );
return i;
}
void MoveThreadIntoProcessorGroup( void* hThread, int groupIndex ) {
__TBB_ASSERT( hardware_concurrency_info == initialization_complete, "MoveThreadIntoProcessorGroup is used before AvailableHwConcurrency" );
if ( !TBB_SetThreadGroupAffinity )
return;
TBB_GROUP_AFFINITY ga = { theProcessorGroups[groupIndex].mask, (WORD)groupIndex, {0,0,0} };
TBB_SetThreadGroupAffinity( hThread, &ga, NULL );
}
int AvailableHwConcurrency() {
atomic_do_once( &initialize_hardware_concurrency_info, hardware_concurrency_info );
return theProcessorGroups[ProcessorGroupInfo::NumGroups - 1].numProcsRunningTotal;
}
/* End of _WIN32||_WIN64 implementation */
#else
#error AvailableHwConcurrency is not implemented for this OS
#endif
} // namespace internal
} // namespace tbb
#endif /* !__TBB_HardwareConcurrency */
internal
Definition: _flow_graph_async_msg_impl.h:24
__TBB_ASSERT
#define __TBB_ASSERT(predicate, comment)
No-op version of __TBB_ASSERT.
Definition: tbb_stddef.h:165
DYNAMIC_LINK_GLOBAL
const int DYNAMIC_LINK_GLOBAL
Definition: dynamic_link.h:77
dynamic_link.h
dynamic_link
OPEN_INTERNAL_NAMESPACE bool dynamic_link(const char *, const dynamic_link_descriptor *, size_t, dynamic_link_handle *handle, int)
Definition: dynamic_link.cpp:564
tbb
The graph class.
Definition: serial/tbb/parallel_for.h:46
tbb::internal::runtime_warning
void __TBB_EXPORTED_FUNC runtime_warning(const char *format,...)
Report a runtime warning.
Definition: tbb_assert_impl.h:85
windows_api.h
tbb::internal::destroy_process_mask
void destroy_process_mask()
Definition: tbb_misc.h:266
tbb::internal::affinity_helper::protect_affinity_mask
void protect_affinity_mask(bool)
Definition: tbb_misc.h:263
dynamic_link_handle
void * dynamic_link_handle
Definition: dynamic_link.h:74
int
void const char const char int ITT_FORMAT __itt_group_sync x void const char ITT_FORMAT __itt_group_sync s void ITT_FORMAT __itt_group_sync p void ITT_FORMAT p void ITT_FORMAT p no args __itt_suppress_mode_t unsigned int void size_t ITT_FORMAT d void ITT_FORMAT p void ITT_FORMAT p __itt_model_site __itt_model_site_instance ITT_FORMAT p __itt_model_task __itt_model_task_instance ITT_FORMAT p void ITT_FORMAT p void ITT_FORMAT p void size_t ITT_FORMAT d void ITT_FORMAT p const wchar_t ITT_FORMAT s const char ITT_FORMAT s const char ITT_FORMAT s const char ITT_FORMAT s no args void ITT_FORMAT p size_t ITT_FORMAT d no args const wchar_t const wchar_t ITT_FORMAT s __itt_heap_function void size_t int ITT_FORMAT d __itt_heap_function void ITT_FORMAT p __itt_heap_function void void size_t int ITT_FORMAT d no args no args unsigned int ITT_FORMAT u const __itt_domain __itt_id ITT_FORMAT lu const __itt_domain __itt_id __itt_id __itt_string_handle ITT_FORMAT p const __itt_domain __itt_id ITT_FORMAT p const __itt_domain __itt_id __itt_timestamp __itt_timestamp ITT_FORMAT lu const __itt_domain __itt_id __itt_id __itt_string_handle ITT_FORMAT p const __itt_domain ITT_FORMAT p const __itt_domain __itt_string_handle unsigned long long ITT_FORMAT lu const __itt_domain __itt_string_handle unsigned long long ITT_FORMAT lu const __itt_domain __itt_id __itt_string_handle __itt_metadata_type size_t void ITT_FORMAT p const __itt_domain __itt_id __itt_string_handle const wchar_t size_t ITT_FORMAT lu const __itt_domain __itt_id __itt_relation __itt_id ITT_FORMAT p const wchar_t int ITT_FORMAT __itt_group_mark d int
Definition: ittnotify_static.h:217
DLD
#define DLD(s, h)
The helper to construct dynamic_link_descriptor structure.
Definition: dynamic_link.h:56
tbb_misc.h
tbb::internal::atomic_do_once
void atomic_do_once(const F &initializer, atomic< do_once_state > &state)
One-time initialization function.
Definition: tbb_misc.h:213
dynamic_unlink
void dynamic_unlink(dynamic_link_handle)
Definition: dynamic_link.cpp:569
tbb::internal::AvailableHwConcurrency
int AvailableHwConcurrency()
Returns maximal parallelism level supported by the current OS configuration.
dynamic_link_descriptor
Association between a handler name and location of pointer to it.
Definition: dynamic_link.h:60
tbb::internal::affinity_helper::dismiss
void dismiss()
Definition: tbb_misc.h:264
tbb::internal::PrintExtraVersionInfo
void PrintExtraVersionInfo(const char *category, const char *format,...)
Prints arbitrary extra TBB version information on stderr.
Definition: tbb_misc.cpp:211
mask
void const char const char int ITT_FORMAT __itt_group_sync x void const char ITT_FORMAT __itt_group_sync s void ITT_FORMAT __itt_group_sync p void ITT_FORMAT p void ITT_FORMAT p no args __itt_suppress_mode_t unsigned int mask
Definition: ittnotify_static.h:109
tbb::internal::initialization_complete
Convenience alias.
Definition: tbb_misc.h:201
DLD_NOWEAK
#define DLD_NOWEAK(s, h)
Definition: dynamic_link.h:57

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