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authorRickard Green <[email protected]>2010-08-16 19:38:33 +0200
committerRickard Green <[email protected]>2010-08-18 18:00:34 +0200
commit1b273b618002d65159453fdfb9520a9476e4423a (patch)
tree1bb787ea400e726e575237274e347bd928787e84 /erts/lib_src/common/erl_misc_utils.c
parentbdfd2aaa1d402b3dd393a7820432f8f76e248ee1 (diff)
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Make it possible to reread and update detected CPU information
Calling erlang:system_info/1 with the new argument 'update_cpu_info' will make the runtime system reread and update the internally stored CPU information. For more information see the documentation of erlang:system_info(update_cpu_info).
Diffstat (limited to 'erts/lib_src/common/erl_misc_utils.c')
-rw-r--r--erts/lib_src/common/erl_misc_utils.c212
1 files changed, 151 insertions, 61 deletions
diff --git a/erts/lib_src/common/erl_misc_utils.c b/erts/lib_src/common/erl_misc_utils.c
index d2ef7140a5..6346fe361d 100644
--- a/erts/lib_src/common/erl_misc_utils.c
+++ b/erts/lib_src/common/erl_misc_utils.c
@@ -62,10 +62,10 @@
#if defined(HAVE_SCHED_xETAFFINITY)
# include <sched.h>
# define ERTS_HAVE_MISC_UTIL_AFFINITY_MASK__
-#define ERTS_MU_GET_PROC_AFFINITY__(CPUINFOP) \
+#define ERTS_MU_GET_PROC_AFFINITY__(CPUINFOP, CPUSET) \
(sched_getaffinity((CPUINFOP)->pid, \
sizeof(cpu_set_t), \
- &(CPUINFOP)->cpuset) != 0 ? -errno : 0)
+ (CPUSET)) != 0 ? -errno : 0)
#define ERTS_MU_SET_THR_AFFINITY__(SETP) \
(sched_setaffinity(0, sizeof(cpu_set_t), (SETP)) != 0 ? -errno : 0)
#elif defined(__WIN32__)
@@ -99,6 +99,26 @@
static int read_topology(erts_cpu_info_t *cpuinfo);
+#if defined(ERTS_HAVE_MISC_UTIL_AFFINITY_MASK__)
+static int
+cpu_sets_are_eq(cpu_set_t *x, cpu_set_t *y)
+{
+ int i;
+ for (i = 0; i < CPU_SETSIZE; i++) {
+ if (CPU_ISSET(i, x)) {
+ if (!CPU_ISSET(i, y))
+ return 0;
+ }
+ else {
+ if (CPU_ISSET(i, y))
+ return 0;
+ }
+ }
+ return 1;
+}
+
+#endif
+
int
erts_milli_sleep(long ms)
{
@@ -137,15 +157,15 @@ struct erts_cpu_info_t_ {
#if defined(__WIN32__)
static __forceinline int
-get_proc_affinity(erts_cpu_info_t *cpuinfo)
+get_proc_affinity(erts_cpu_info_t *cpuinfo, cpu_set_t *cpuset)
{
DWORD pamask, samask;
if (GetProcessAffinityMask(GetCurrentProcess(), &pamask, &samask)) {
- cpuinfo->cpuset = (cpu_set_t) pamask;
+ *cpuset = (cpu_set_t) pamask;
return 0;
}
else {
- cpuinfo->cpuset = (cpu_set_t) 0;
+ *cpuset = (cpu_set_t) 0;
return -erts_get_last_win_errno();
}
}
@@ -179,6 +199,9 @@ erts_cpu_info_create(void)
#endif
cpuinfo->topology_size = 0;
cpuinfo->topology = NULL;
+ cpuinfo->configured = -1;
+ cpuinfo->online = -1;
+ cpuinfo->available = -1;
erts_cpu_info_update(cpuinfo);
return cpuinfo;
}
@@ -203,34 +226,40 @@ erts_cpu_info_destroy(erts_cpu_info_t *cpuinfo)
}
}
-void
+int
erts_cpu_info_update(erts_cpu_info_t *cpuinfo)
{
- cpuinfo->configured = 0;
- cpuinfo->online = 0;
- cpuinfo->available = 0;
+ int changed = 0;
+ int configured = 0;
+ int online = 0;
+ int available = 0;
+ erts_cpu_topology_t *old_topology;
+ int old_topology_size;
+#if defined(ERTS_HAVE_MISC_UTIL_AFFINITY_MASK__)
+ cpu_set_t cpuset;
+#endif
#ifdef __WIN32__
{
int i;
SYSTEM_INFO sys_info;
GetSystemInfo(&sys_info);
- cpuinfo->configured = (int) sys_info.dwNumberOfProcessors;
+ configured = (int) sys_info.dwNumberOfProcessors;
for (i = 0; i < sizeof(DWORD)*8; i++)
if (sys_info.dwActiveProcessorMask & (((DWORD) 1) << i))
- cpuinfo->online++;
+ online++;
}
#elif !defined(NO_SYSCONF) && (defined(_SC_NPROCESSORS_CONF) \
|| defined(_SC_NPROCESSORS_ONLN))
#ifdef _SC_NPROCESSORS_CONF
- cpuinfo->configured = (int) sysconf(_SC_NPROCESSORS_CONF);
- if (cpuinfo->configured < 0)
- cpuinfo->configured = 0;
+ configured = (int) sysconf(_SC_NPROCESSORS_CONF);
+ if (configured < 0)
+ configured = 0;
#endif
#ifdef _SC_NPROCESSORS_ONLN
- cpuinfo->online = (int) sysconf(_SC_NPROCESSORS_ONLN);
- if (cpuinfo->online < 0)
- cpuinfo->online = 0;
+ online = (int) sysconf(_SC_NPROCESSORS_ONLN);
+ if (online < 0)
+ online = 0;
#endif
#elif defined(HAVE_SYS_SYSCTL_H) && defined(CTL_HW) && (defined(HW_NCPU) \
|| defined(HW_AVAILCPU))
@@ -242,71 +271,138 @@ erts_cpu_info_update(erts_cpu_info_t *cpuinfo)
len = sizeof(int);
mib[0] = CTL_HW;
mib[1] = HW_NCPU;
- if (sysctl(&mib[0], 2, &cpuinfo->configured, &len, NULL, 0) < 0)
- cpuinfo->configured = 0;
+ if (sysctl(&mib[0], 2, &configured, &len, NULL, 0) < 0)
+ configured = 0;
#endif
#ifdef HW_AVAILCPU
len = sizeof(int);
mib[0] = CTL_HW;
mib[1] = HW_AVAILCPU;
- if (sysctl(&mib[0], 2, &cpuinfo->online, &len, NULL, 0) < 0)
- cpuinfo->online = 0;
+ if (sysctl(&mib[0], 2, &online, &len, NULL, 0) < 0)
+ online = 0;
#endif
}
#endif
- if (cpuinfo->online > cpuinfo->configured)
- cpuinfo->online = cpuinfo->configured;
+ if (online > configured)
+ online = configured;
+
+ if (cpuinfo->configured != configured)
+ changed = 1;
+ if (cpuinfo->online != online)
+ changed = 1;
#if defined(ERTS_HAVE_MISC_UTIL_AFFINITY_MASK__)
- if (ERTS_MU_GET_PROC_AFFINITY__(cpuinfo) == 0) {
- int i, c, cn, si;
- c = cn = 0;
- si = sizeof(cpuinfo->affinity_str_buf) - 1;
- cpuinfo->affinity_str_buf[si] = '\0';
- for (i = 0; i < CPU_SETSIZE; i++) {
- if (CPU_ISSET(i, &cpuinfo->cpuset)) {
- c |= 1 << cn;
- cpuinfo->available++;
+ if (ERTS_MU_GET_PROC_AFFINITY__(cpuinfo, &cpuset) == 0) {
+ if (!changed && !cpu_sets_are_eq(&cpuset, &cpuinfo->cpuset))
+ changed = 1;
+
+ if (!changed)
+ available = cpuinfo->available;
+ else {
+ int i, c, cn, si;
+
+ memcpy((void *) &cpuinfo->cpuset,
+ (void *) &cpuset,
+ sizeof(cpu_set_t));
+
+ c = cn = 0;
+ si = sizeof(cpuinfo->affinity_str_buf) - 1;
+ cpuinfo->affinity_str_buf[si] = '\0';
+ for (i = 0; i < CPU_SETSIZE; i++) {
+ if (CPU_ISSET(i, &cpuinfo->cpuset)) {
+ c |= 1 << cn;
+ available++;
+ }
+ cn++;
+ if (cn == 4) {
+ cpuinfo->affinity_str_buf[--si] = (c < 10
+ ? '0' + c
+ : 'A' + c - 10);
+ c = cn = 0;
+ }
}
- cn++;
- if (cn == 4) {
+ if (c)
cpuinfo->affinity_str_buf[--si] = (c < 10
? '0' + c
: 'A' + c - 10);
- c = cn = 0;
- }
+ while (cpuinfo->affinity_str_buf[si] == '0')
+ si++;
+ cpuinfo->affinity_str = &cpuinfo->affinity_str_buf[si];
}
- if (c)
- cpuinfo->affinity_str_buf[--si] = (c < 10
- ? '0' + c
- : 'A' + c - 10);
- while (cpuinfo->affinity_str_buf[si] == '0')
- si++;
- cpuinfo->affinity_str = &cpuinfo->affinity_str_buf[si];
}
#elif defined(HAVE_PSET_INFO)
{
- uint_t numcpus = cpuinfo->configured;
- if (cpuinfo->cpuids)
- free(cpuinfo->cpuids);
- cpuinfo->cpuids = malloc(sizeof(processorid_t)*numcpus);
- if (cpuinfo->cpuids) {
- if (pset_info(PS_MYID, NULL, &numcpus, &cpuinfo->cpuids) == 0)
- cpuinfo->available = (int) numcpus;
- if (cpuinfo->available < 0) {
- free(cpuinfo->cpuid);
- cpuinfo->available = 0;
+ processorid_t *cpuids;
+ uint_t numcpus = configured;
+ cpuids = malloc(sizeof(processorid_t)*numcpus);
+ if (cpuids) {
+ if (pset_info(PS_MYID, NULL, &numcpus, &cpuids) == 0)
+ available = (int) numcpus;
+ if (available < 0) {
+ free(cpuids);
+ cpuids = NULL;
+ available = 0;
}
}
+ if (!cpuids) {
+ if (cpuinfo->cpuids)
+ changed = 1;
+ }
+ else {
+ if (cpuinfo->cpuids)
+ changed = 1;
+ if (memcmp((void *) cpuinfo->cpuids,
+ (void *) cpuids,
+ sizeof(processorid_t)*numcpus) != 0)
+ changed = 1;
+
+ }
+ if (!changed) {
+ if (cpuids)
+ free(cpuids);
+ }
+ else {
+ if (cpuinfo->cpuids)
+ free(cpuinfo->cpuids);
+ cpuinfo->cpuids = cpuids;
+ }
}
#endif
- if (cpuinfo->available > cpuinfo->online)
- cpuinfo->available = cpuinfo->online;
+ if (available > online)
+ available = online;
+
+ if (cpuinfo->available != available)
+ changed = 1;
+
+ cpuinfo->configured = configured;
+ cpuinfo->online = online;
+ cpuinfo->available = available;
+
+ old_topology = cpuinfo->topology;
+ old_topology_size = cpuinfo->topology_size;
+ cpuinfo->topology = NULL;
read_topology(cpuinfo);
+ if (cpuinfo->topology_size != old_topology_size
+ || (old_topology_size != 0
+ && memcmp((void *) cpuinfo->topology,
+ (void *) old_topology,
+ (sizeof(erts_cpu_topology_t)
+ * old_topology_size)) != 0)) {
+ changed = 1;
+ if (old_topology)
+ free(old_topology);
+ }
+ else {
+ if (cpuinfo->topology)
+ free(cpuinfo->topology);
+ cpuinfo->topology = old_topology;
+ }
+
+ return changed;
}
int
@@ -641,9 +737,6 @@ read_topology(erts_cpu_info_t *cpuinfo)
errno = 0;
- if (cpuinfo->topology)
- free(cpuinfo->topology);
-
if (cpuinfo->configured < 1)
goto error;
@@ -896,9 +989,6 @@ read_topology(erts_cpu_info_t *cpuinfo)
errno = 0;
- if (cpuinfo->topology)
- free(cpuinfo->topology);
-
if (cpuinfo->configured < 1)
goto error;