From ef8d96c29c73b9da8cdaa2b8b4737862c85ccc20 Mon Sep 17 00:00:00 2001
From: Vadim Zeitlin <vadim@wxwidgets.org>
Date: Mon, 6 Dec 1999 12:31:04 +0000
Subject: [PATCH] wxThread::GetCPUCount() and SetConcurrency() added and
documented
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@4837 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
---
docs/changes.txt | 4 ++-
docs/latex/wx/thread.tex | 21 ++++++++++++
include/wx/thread.h | 15 +++++++++
samples/console/console.cpp | 6 ++--
src/common/textfile.cpp | 5 +++
src/msw/thread.cpp | 11 +++++++
src/unix/threadpsx.cpp | 66 +++++++++++++++++++++++++++++++++++++
7 files changed, 125 insertions(+), 3 deletions(-)
diff --git a/docs/changes.txt b/docs/changes.txt
index 861a746147..ee12fcb7d0 100644
--- a/docs/changes.txt
+++ b/docs/changes.txt
@@ -6,7 +6,9 @@ next release (2.1.12 or 2.2?)
wxBase:
-- wxThread class modified to support both detached and joinable threads
+- wxThread class modified to support both detached and joinable threads, also
+ added new GetCPUCount() and SetConcurrency() functions (useful under Solaris
+ only so far)
- wxLog functions are now (more) MT-safe
- wxStopWatch class, timer functions have more chances to return correct
results for your platform (use ANSI function where available)
diff --git a/docs/latex/wx/thread.tex b/docs/latex/wx/thread.tex
index cfdbc20879..f7c4a1997e 100644
--- a/docs/latex/wx/thread.tex
+++ b/docs/latex/wx/thread.tex
@@ -127,6 +127,16 @@ joinable threads and is the value returned by \helpref{Wait}{wxthreadwait}.
This function is called by wxWindows itself and should never be called
directly.
+\membersection{wxThread::GetCPUCount}\label{wxthreadgetcpucount}
+
+\func{static int}{GetCPUCount}{\void}
+
+Returns the number of system CPUs or -1 if the value is unknown.
+
+\wxheading{See also}
+
+\helpref{SetConcurrency}{wxthreadsetconcurrency}
+
\membersection{wxThread::GetId}\label{wxthreadgetid}
\constfunc{unsigned long}{GetId}{\void}
@@ -253,6 +263,17 @@ Resumes a thread suspended by the call to \helpref{Pause}{wxthreadpause}.
This function can only be called from another thread context.
+\membersection{wxThread::SetConcurrency}\label{wxthreadsetconcurrency}
+
+\func{static bool}{SetConcurrency}{\param{size\_t }{level}}
+
+Sets the thread concurrency level for this process. This is, roughly, the
+number of threads that the system tries to schedule to run in parallel.
+The value of $0$ for {\it level} may be used to set the default one.
+
+Returns TRUE on success or FALSE otherwise (for example, if this function is
+not implemented for this platform (currently everything except Solaris)).
+
\membersection{wxThread::TestDestroy}\label{wxthreadtestdestroy}
\func{bool}{TestDestroy}{\void}
diff --git a/include/wx/thread.h b/include/wx/thread.h
index 7c9df994de..a4c4b465df 100644
--- a/include/wx/thread.h
+++ b/include/wx/thread.h
@@ -280,6 +280,21 @@ public:
// NB: at least under MSW worker threads can not call ::wxSleep()!
static void Sleep(unsigned long milliseconds);
+ // get the number of system CPUs - useful with SetConcurrency()
+ // (the "best" value for it is usually number of CPUs + 1)
+ //
+ // Returns -1 if unknown, number of CPUs otherwise
+ static int GetCPUCount();
+
+ // sets the concurrency level: this is, roughly, the number of threads
+ // the system tries to schedule to run in parallel. 0 means the
+ // default value (usually acceptable, but may not yield the best
+ // performance for this process)
+ //
+ // Returns TRUE on success, FALSE otherwise (if not implemented, for
+ // example)
+ static bool SetConcurrency(size_t level);
+
// constructor only creates the C++ thread object and doesn't create (or
// start) the real thread
wxThread(wxThreadKind kind = wxTHREAD_DETACHED);
diff --git a/samples/console/console.cpp b/samples/console/console.cpp
index 981a302ac3..0a08f86c14 100644
--- a/samples/console/console.cpp
+++ b/samples/console/console.cpp
@@ -32,8 +32,8 @@
//#define TEST_ARRAYS
//#define TEST_LOG
//#define TEST_STRINGS
-//#define TEST_THREADS
-#define TEST_TIME
+#define TEST_THREADS
+//#define TEST_TIME
//#define TEST_LONGLONG
// ============================================================================
@@ -647,6 +647,8 @@ int main(int argc, char **argv)
#endif // TEST_LOG
#ifdef TEST_THREADS
+ printf("This system has %d CPUs\n", wxThread::GetCPUCount());
+
if ( argc > 1 && argv[1][0] == 't' )
wxLog::AddTraceMask("thread");
diff --git a/src/common/textfile.cpp b/src/common/textfile.cpp
index 9b35dfd8de..5c74b3ab57 100644
--- a/src/common/textfile.cpp
+++ b/src/common/textfile.cpp
@@ -145,6 +145,11 @@ wxTextFile::~wxTextFile()
// file operations
// ----------------------------------------------------------------------------
+bool wxTextFile::Exists() const
+{
+ return wxFile::Exists(m_strFile);
+}
+
bool wxTextFile::Open(const wxString& strFile)
{
m_strFile = strFile;
diff --git a/src/msw/thread.cpp b/src/msw/thread.cpp
index 3ae5d7b979..35838d9a29 100644
--- a/src/msw/thread.cpp
+++ b/src/msw/thread.cpp
@@ -527,6 +527,17 @@ void wxThread::Sleep(unsigned long milliseconds)
::Sleep(milliseconds);
}
+int wxThread::GetCPUCount()
+{
+ return -1;
+}
+
+bool wxThread::SetConcurrency(size_t level)
+{
+ // ok only for the default one
+ return level == 0;
+}
+
// ctor and dtor
// -------------
diff --git a/src/unix/threadpsx.cpp b/src/unix/threadpsx.cpp
index fad73a2df9..34f3cd81b4 100644
--- a/src/unix/threadpsx.cpp
+++ b/src/unix/threadpsx.cpp
@@ -45,6 +45,15 @@
#include <sched.h>
#endif
+#ifdef HAVE_THR_SETCONCURRENCY
+ #include <thread.h>
+#endif
+
+// we use wxFFile under Linux in GetCPUCount()
+#ifdef __LINUX__
+ #include "wx/ffile.h"
+#endif
+
// ----------------------------------------------------------------------------
// constants
// ----------------------------------------------------------------------------
@@ -834,6 +843,63 @@ void wxThread::Sleep(unsigned long milliseconds)
wxUsleep(milliseconds);
}
+int wxThread::GetCPUCount()
+{
+#if defined(__LINUX__)
+ // read from proc (can't use wxTextFile here because it's a special file:
+ // it has 0 size but still can be read from)
+ wxLogNull nolog;
+
+ wxFFile file(_T("/proc/cpuinfo"));
+ if ( file.IsOpened() )
+ {
+ // slurp the whole file
+ wxString s;
+ if ( file.ReadAll(&s) )
+ {
+ // (ab)use Replace() to find the number of "processor" strings
+ size_t count = s.Replace(_T("processor"), _T(""));
+ if ( count > 0 )
+ {
+ return count;
+ }
+
+ wxLogDebug(_T("failed to parse /proc/cpuinfo"));
+ }
+ else
+ {
+ wxLogDebug(_T("failed to read /proc/cpuinfo"));
+ }
+ }
+#elif defined(_SC_NPROCESSORS_ONLN)
+ // this works for Solaris
+ int rc = sysconf(_SC_NPROCESSORS_ONLN);
+ if ( rc != -1 )
+ {
+ return rc;
+ }
+#endif // different ways to get number of CPUs
+
+ // unknown
+ return -1;
+}
+
+bool wxThread::SetConcurrency(size_t level)
+{
+#ifdef HAVE_THR_SETCONCURRENCY
+ int rc = thr_setconcurrency(level);
+ if ( rc != 0 )
+ {
+ wxLogSysError(rc, _T("thr_setconcurrency() failed"));
+ }
+
+ return rc == 0;
+#else // !HAVE_THR_SETCONCURRENCY
+ // ok only for the default value
+ return level == 0;
+#endif // HAVE_THR_SETCONCURRENCY/!HAVE_THR_SETCONCURRENCY
+}
+
// -----------------------------------------------------------------------------
// creating thread
// -----------------------------------------------------------------------------
--
2.47.2