[Git][ghc/ghc][master] 3 commits: rts: Teach getNumProcessors to return available processors
Marge Bot
gitlab at gitlab.haskell.org
Sat May 30 10:07:41 UTC 2020
Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC
Commits:
4413828b by Ben Gamari at 2020-05-30T06:07:31-04:00
rts: Teach getNumProcessors to return available processors
Previously we would report the number of physical processors, which
can be quite wrong in a containerized setting. Now we rather return how
many processors are in our affinity mask when possible.
I also refactored the code to prefer platform-specific since this will
report logical CPUs instead of physical (using
`machdep.cpu.thread_count` on Darwin and `cpuset_getaffinity` on FreeBSD).
Fixes #14781.
- - - - -
1449435c by Ben Gamari at 2020-05-30T06:07:31-04:00
users-guide: Note change in getNumProcessors in users guide
- - - - -
3d960169 by Ben Gamari at 2020-05-30T06:07:31-04:00
rts: Drop compatibility shims for Windows Vista
We can now assume that the thread and processor group interfaces are
available.
- - - - -
7 changed files:
- configure.ac
- docs/users_guide/8.12.1-notes.rst
- docs/users_guide/using-concurrent.rst
- hadrian/src/Settings/Packages.hs
- rts/ghc.mk
- rts/posix/OSThreads.c
- rts/win32/OSThreads.c
Changes:
=====================================
configure.ac
=====================================
@@ -978,7 +978,7 @@ FP_CHECK_FUNC([GetModuleFileName],
dnl ** check for more functions
dnl ** The following have been verified to be used in ghc/, but might be used somewhere else, too.
-AC_CHECK_FUNCS([getclock getrusage gettimeofday setitimer siginterrupt sysconf times ctime_r sched_setaffinity setlocale])
+AC_CHECK_FUNCS([getclock getrusage gettimeofday setitimer siginterrupt sysconf times ctime_r sched_setaffinity sched_getaffinity setlocale])
dnl ** On OS X 10.4 (at least), time.h doesn't declare ctime_r if
dnl ** _POSIX_C_SOURCE is defined
=====================================
docs/users_guide/8.12.1-notes.rst
=====================================
@@ -17,7 +17,7 @@ Highlights
digit improvements in runtime for inner loops.
In the mean this improved runtime by about 0.8%. For details
- see ticket #17823.
+ see ticket :ghc-ticket:`17823`.
Full details
------------
@@ -95,7 +95,7 @@ Language
effectively allows users to choose which variables can or can't be
instantiated through visible type application. More information can be found
here: :ref:`Manually-defining-inferred-variables`.
-
+
Compiler
~~~~~~~~
@@ -105,11 +105,18 @@ GHCi
- The ``:script`` command now allows for file names that contain spaces to
passed as arguments: either by enclosing the file names in double quotes or by
- escaping spaces in file names with a backslash. (#18027)
+ escaping spaces in file names with a backslash. (:ghc-ticket:`18027`)
Runtime system
~~~~~~~~~~~~~~
+- :rts-flag:`-N` without a count now tries to respect the number of processors
+ in the process's affinity mask, making GHC's behavior more predictable in
+ containerized settings (:ghc-ticket:`14781`).
+
+- Support for Windows Vista has been dropped. GHC-compiled programs now require
+ Windows 7 or later.
+
Template Haskell
~~~~~~~~~~~~~~~~
=====================================
docs/users_guide/using-concurrent.rst
=====================================
@@ -111,6 +111,7 @@ There are two ways to run a program on multiple processors: call
use the RTS :rts-flag:`-N ⟨x⟩` options.
.. rts-flag:: -N ⟨x⟩
+ -N
-maxN ⟨x⟩
Use ⟨x⟩ simultaneous threads when running the program.
=====================================
hadrian/src/Settings/Packages.hs
=====================================
@@ -462,4 +462,4 @@ rtsWarnings = mconcat
-- and also centralizes the versioning.
-- | Minimum supported Windows version.
windowsVersion :: String
-windowsVersion = "0x06000100"
+windowsVersion = "0x06010000"
=====================================
rts/ghc.mk
=====================================
@@ -25,7 +25,7 @@ rts_VERSION = 1.0
# If we're compiling on windows, enforce that we only support Vista SP1+
# Adding this here means it doesn't have to be done in individual .c files
# and also centralizes the versioning.
-rts_WINVER = 0x06000100
+rts_WINVER = 0x06010000
# merge GhcLibWays and GhcRTSWays but strip out duplicates
rts_WAYS = $(GhcLibWays) $(filter-out $(GhcLibWays),$(GhcRTSWays))
=====================================
rts/posix/OSThreads.c
=====================================
@@ -240,26 +240,50 @@ forkOS_createThread ( HsStablePtr entry )
void freeThreadingResources (void) { /* nothing */ }
+// Get the number of logical CPU cores available to us. Note that this is
+// different from the number of physical cores (see #14781).
uint32_t
getNumberOfProcessors (void)
{
static uint32_t nproc = 0;
if (nproc == 0) {
-#if defined(HAVE_SYSCONF) && defined(_SC_NPROCESSORS_ONLN)
- nproc = sysconf(_SC_NPROCESSORS_ONLN);
-#elif defined(HAVE_SYSCONF) && defined(_SC_NPROCESSORS_CONF)
- nproc = sysconf(_SC_NPROCESSORS_CONF);
-#elif defined(darwin_HOST_OS)
+#if defined(HAVE_SCHED_GETAFFINITY)
+ cpu_set_t mask;
+ CPU_ZERO(&mask);
+ if (sched_getaffinity(0, sizeof(mask), &mask) == 0) {
+ for (int i = 0; i < CPU_SETSIZE; i++) {
+ if (CPU_ISSET(i, &mask))
+ nproc++;
+ }
+ return nproc;
+ }
+#endif
+
+#if defined(darwin_HOST_OS)
size_t size = sizeof(uint32_t);
- if(sysctlbyname("hw.logicalcpu",&nproc,&size,NULL,0) != 0) {
+ if (sysctlbyname("machdep.cpu.thread_count",&nproc,&size,NULL,0) != 0) {
+ if (sysctlbyname("hw.logicalcpu",&nproc,&size,NULL,0) != 0) {
+ if (sysctlbyname("hw.ncpu",&nproc,&size,NULL,0) != 0)
+ nproc = 1;
+ }
+ }
+#elif defined(freebsd_HOST_OS)
+ cpuset_t mask;
+ CPU_ZERO(&mask);
+ if(cpuset_getaffinity(CPU_LEVEL_CPUSET, CPU_WHICH_PID, -1, sizeof(mask), &mask) == 0) {
+ return CPU_COUNT(&mask);
+ } else {
+ size_t size = sizeof(uint32_t);
if(sysctlbyname("hw.ncpu",&nproc,&size,NULL,0) != 0)
nproc = 1;
}
-#elif defined(freebsd_HOST_OS)
- size_t size = sizeof(uint32_t);
- if(sysctlbyname("hw.ncpu",&nproc,&size,NULL,0) != 0)
- nproc = 1;
+#elif defined(HAVE_SYSCONF) && defined(_SC_NPROCESSORS_ONLN)
+ // N.B. This is the number of physical processors.
+ nproc = sysconf(_SC_NPROCESSORS_ONLN);
+#elif defined(HAVE_SYSCONF) && defined(_SC_NPROCESSORS_CONF)
+ // N.B. This is the number of physical processors.
+ nproc = sysconf(_SC_NPROCESSORS_CONF);
#else
nproc = 1;
#endif
=====================================
rts/win32/OSThreads.c
=====================================
@@ -252,17 +252,6 @@ forkOS_createThread ( HsStablePtr entry )
(unsigned*)&pId) == 0);
}
-#if defined(x86_64_HOST_ARCH)
-/* We still support Windows Vista, so we can't depend on it
- and must manually resolve these. */
-typedef DWORD(WINAPI *GetItemCountProc)(WORD);
-typedef DWORD(WINAPI *GetGroupCountProc)(void);
-typedef BOOL(WINAPI *SetThreadGroupAffinityProc)(HANDLE, const GROUP_AFFINITY*, PGROUP_AFFINITY);
-#if !defined(ALL_PROCESSOR_GROUPS)
-#define ALL_PROCESSOR_GROUPS 0xffff
-#endif
-#endif
-
void freeThreadingResources (void)
{
if (cpuGroupCache)
@@ -310,13 +299,6 @@ getNumberOfProcessorsGroups (void)
#if defined(x86_64_HOST_ARCH)
if (!n_groups)
{
- /* We still support Windows Vista. Which means we can't rely
- on the API being available. So we'll have to resolve manually. */
- HMODULE kernel = GetModuleHandleW(L"kernel32");
-
- GetGroupCountProc GetActiveProcessorGroupCount
- = (GetGroupCountProc)(void*)
- GetProcAddress(kernel, "GetActiveProcessorGroupCount");
n_groups = GetActiveProcessorGroupCount();
IF_DEBUG(scheduler, debugBelch("[*] Number of processor groups detected: %u\n", n_groups));
@@ -346,21 +328,10 @@ getProcessorsDistribution (void)
cpuGroupDistCache = malloc(n_groups * sizeof(uint8_t));
memset(cpuGroupDistCache, MAXIMUM_PROCESSORS, n_groups * sizeof(uint8_t));
- /* We still support Windows Vista. Which means we can't rely
- on the API being available. So we'll have to resolve manually. */
- HMODULE kernel = GetModuleHandleW(L"kernel32");
-
- GetItemCountProc GetActiveProcessorCount
- = (GetItemCountProc)(void*)
- GetProcAddress(kernel, "GetActiveProcessorCount");
-
- if (GetActiveProcessorCount)
+ for (int i = 0; i < n_groups; i++)
{
- for (int i = 0; i < n_groups; i++)
- {
- cpuGroupDistCache[i] = GetActiveProcessorCount(i);
- IF_DEBUG(scheduler, debugBelch("[*] Number of active processors in group %u detected: %u\n", i, cpuGroupDistCache[i]));
- }
+ cpuGroupDistCache[i] = GetActiveProcessorCount(i);
+ IF_DEBUG(scheduler, debugBelch("[*] Number of active processors in group %u detected: %u\n", i, cpuGroupDistCache[i]));
}
}
@@ -449,14 +420,7 @@ getNumberOfProcessors (void)
static uint32_t nproc = 0;
#if defined(x86_64_HOST_ARCH)
- /* We still support Windows Vista. Which means we can't rely
- on the API being available. So we'll have to resolve manually. */
- HMODULE kernel = GetModuleHandleW(L"kernel32");
-
- GetItemCountProc GetActiveProcessorCount
- = (GetItemCountProc)(void*)
- GetProcAddress(kernel, "GetActiveProcessorCount");
- if (GetActiveProcessorCount && !nproc)
+ if (!nproc)
{
nproc = GetActiveProcessorCount(ALL_PROCESSOR_GROUPS);
@@ -517,21 +481,11 @@ setThreadAffinity (uint32_t n, uint32_t m) // cap N of M
mask[group] |= 1 << ix;
}
-#if defined(x86_64_HOST_ARCH)
- /* We still support Windows Vista. Which means we can't rely
- on the API being available. So we'll have to resolve manually. */
- HMODULE kernel = GetModuleHandleW(L"kernel32");
-
- SetThreadGroupAffinityProc SetThreadGroupAffinity
- = (SetThreadGroupAffinityProc)(void*)
- GetProcAddress(kernel, "SetThreadGroupAffinity");
-#endif
-
for (i = 0; i < n_groups; i++)
{
#if defined(x86_64_HOST_ARCH)
// If we support the new API, use it.
- if (mask[i] > 0 && SetThreadGroupAffinity)
+ if (mask[i] > 0)
{
GROUP_AFFINITY hGroup;
ZeroMemory(&hGroup, sizeof(hGroup));
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/aac19e6caa0c94e159610f124114186ee20bcdd1...3d96016926cc88506db416f87b6e4b68a3a0d25f
--
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/aac19e6caa0c94e159610f124114186ee20bcdd1...3d96016926cc88506db416f87b6e4b68a3a0d25f
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