From 1b273b618002d65159453fdfb9520a9476e4423a Mon Sep 17 00:00:00 2001 From: Rickard Green Date: Mon, 16 Aug 2010 19:38:33 +0200 Subject: 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). --- erts/doc/src/erlang.xml | 55 ++++++++- erts/emulator/beam/erl_bif_info.c | 24 +++- erts/emulator/beam/erl_process.c | 35 +++++- erts/emulator/beam/erl_process.h | 1 + erts/include/internal/erl_misc_utils.h | 4 +- erts/lib_src/common/erl_misc_utils.c | 212 +++++++++++++++++++++++---------- 6 files changed, 258 insertions(+), 73 deletions(-) diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml index 54a0a80536..cb3112acfe 100644 --- a/erts/doc/src/erlang.xml +++ b/erts/doc/src/erlang.xml @@ -5533,7 +5533,7 @@ true CpuTopology type to change.

- {cpu_topology, defined} + {cpu_topology, defined}

Returns the user defined CpuTopology. For more information see the documentation of @@ -5543,7 +5543,7 @@ true argument.

- {cpu_topology, detected} + {cpu_topology, detected}

Returns the automatically detected CpuTopology. The emulator currently only detects the CPU topology on some newer @@ -5727,11 +5727,34 @@ true information see the "How to interpret the Erlang crash dumps" chapter in the ERTS User's Guide.

 - logical_processors + logical_processors -

Returns the number of logical processors detected on the - system as an integer or the atom unknown if the - emulator wasn't able to detect any. +

Returns the detected number of logical processors configured + on the system. The return value is either an integer, or + the atom unknown if the emulator wasn't able to + detect logical processors configured. +

+ + logical_processors_available + +

Returns the detected number of logical processors available to + the Erlang runtime system. The return value is either an + integer, or the atom unknown if the emulator wasn't + able to detect logical processors available. The number + of logical processors available is less than or equal to + the number of logical + processors online. +

+ + logical_processors_online + +

Returns the detected number of logical processors online on + the system. The return value is either an integer, + or the atom unknown if the emulator wasn't able to + detect logical processors online. The number of logical + processors online is less than or equal to the number of + logical processors + configured.

machine @@ -5936,6 +5959,26 @@ true get_tcw in "Match Specifications in Erlang", ERTS User's Guide.

+ update_cpu_info + +

The runtime system rereads the CPU information available and + updates its internally stored information about the + detected CPU + topology and the amount of logical processors + configured, + online, and + available. + If the CPU information has changed since the last time it was read, + the atom changed is returned; otherwise, the atom + unchanged is returned. If the CPU information has changed + you probably want to + adjust the amount + of schedulers online. You typically want to have as + many schedulers online as + logical processors + available. +

+ version

Returns a string containing the version number of the diff --git a/erts/emulator/beam/erl_bif_info.c b/erts/emulator/beam/erl_bif_info.c index 5128776c47..d5ae3d2174 100644 --- a/erts/emulator/beam/erl_bif_info.c +++ b/erts/emulator/beam/erl_bif_info.c @@ -2316,6 +2316,15 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1) } else if (ERTS_IS_ATOM_STR("cpu_topology", BIF_ARG_1)) { res = erts_get_cpu_topology_term(BIF_P, am_used); BIF_TRAP1(erts_format_cpu_topology_trap, BIF_P, res); + } else if (ERTS_IS_ATOM_STR("update_cpu_info", BIF_ARG_1)) { + if (erts_update_cpu_info()) { + ERTS_DECL_AM(changed); + BIF_RET(AM_changed); + } + else { + ERTS_DECL_AM(unchanged); + BIF_RET(AM_unchanged); + } #if defined(__GNUC__) && defined(HAVE_SOLARIS_SPARC_PERFMON) } else if (ERTS_IS_ATOM_STR("ultrasparc_read_tick1", BIF_ARG_1)) { register unsigned high asm("%l0"); @@ -2387,7 +2396,10 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1) } /* Arguments that are unusual follow ... */ else if (ERTS_IS_ATOM_STR("logical_processors", BIF_ARG_1)) { - int no = erts_get_cpu_configured(erts_cpuinfo); + int no; + erts_smp_rwmtx_rlock(&erts_cpu_bind_rwmtx); + no = erts_get_cpu_configured(erts_cpuinfo); + erts_smp_rwmtx_runlock(&erts_cpu_bind_rwmtx); if (no > 0) BIF_RET(make_small((Uint) no)); else { @@ -2396,7 +2408,10 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1) } } else if (ERTS_IS_ATOM_STR("logical_processors_online", BIF_ARG_1)) { - int no = erts_get_cpu_online(erts_cpuinfo); + int no; + erts_smp_rwmtx_rlock(&erts_cpu_bind_rwmtx); + no = erts_get_cpu_online(erts_cpuinfo); + erts_smp_rwmtx_runlock(&erts_cpu_bind_rwmtx); if (no > 0) BIF_RET(make_small((Uint) no)); else { @@ -2405,7 +2420,10 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1) } } else if (ERTS_IS_ATOM_STR("logical_processors_available", BIF_ARG_1)) { - int no = erts_get_cpu_available(erts_cpuinfo); + int no; + erts_smp_rwmtx_rlock(&erts_cpu_bind_rwmtx); + no = erts_get_cpu_available(erts_cpuinfo); + erts_smp_rwmtx_runlock(&erts_cpu_bind_rwmtx); if (no > 0) BIF_RET(make_small((Uint) no)); else { diff --git a/erts/emulator/beam/erl_process.c b/erts/emulator/beam/erl_process.c index a644520442..457e283034 100644 --- a/erts/emulator/beam/erl_process.c +++ b/erts/emulator/beam/erl_process.c @@ -3962,7 +3962,7 @@ check_cpu_bind(ErtsSchedulerData *esdp) goto unbind; } } - else if (cpu_id < 0 && scheduler2cpu_map[esdp->no].bound_id >= 0) { + else if (cpu_id < 0) /* && scheduler2cpu_map[esdp->no].bound_id >= 0) */ { unbind: /* Get rid of old binding */ res = erts_unbind_from_cpu(erts_cpuinfo); @@ -5521,6 +5521,39 @@ late_cpu_bind_init(void) } } +int +erts_update_cpu_info(void) +{ + int changed; + erts_smp_rwmtx_rwlock(&erts_cpu_bind_rwmtx); + changed = erts_cpu_info_update(erts_cpuinfo); + if (changed) { + erts_cpu_topology_t *cpudata; + int cpudata_size; + erts_free(ERTS_ALC_T_CPUDATA, system_cpudata); + + system_cpudata_size = erts_get_cpu_topology_size(erts_cpuinfo); + system_cpudata = erts_alloc(ERTS_ALC_T_CPUDATA, + (sizeof(erts_cpu_topology_t) + * system_cpudata_size)); + + if (!erts_get_cpu_topology(erts_cpuinfo, system_cpudata) + || ERTS_INIT_CPU_TOPOLOGY_OK != verify_topology(system_cpudata, + system_cpudata_size)) { + erts_free(ERTS_ALC_T_CPUDATA, system_cpudata); + system_cpudata = NULL; + system_cpudata_size = 0; + } + + create_tmp_cpu_topology_copy(&cpudata, &cpudata_size); + ASSERT(cpudata); + signal_schedulers_bind_change(cpudata, cpudata_size); + destroy_tmp_cpu_topology_copy(cpudata); + } + erts_smp_rwmtx_rwunlock(&erts_cpu_bind_rwmtx); + return changed; +} + #ifdef ERTS_SMP static void diff --git a/erts/emulator/beam/erl_process.h b/erts/emulator/beam/erl_process.h index c3fef6d38e..0cc4a715ad 100644 --- a/erts/emulator/beam/erl_process.h +++ b/erts/emulator/beam/erl_process.h @@ -1025,6 +1025,7 @@ int erts_init_scheduler_bind_type(char *how); #define ERTS_INIT_CPU_TOPOLOGY_MISSING 9 int erts_init_cpu_topology(char *topology_str); +int erts_update_cpu_info(void); void erts_pre_init_process(void); void erts_late_init_process(void); diff --git a/erts/include/internal/erl_misc_utils.h b/erts/include/internal/erl_misc_utils.h index 6b875ff824..dda2cab5c6 100644 --- a/erts/include/internal/erl_misc_utils.h +++ b/erts/include/internal/erl_misc_utils.h @@ -1,7 +1,7 @@ /* * %CopyrightBegin% * - * Copyright Ericsson AB 2006-2009. All Rights Reserved. + * Copyright Ericsson AB 2006-2010. All Rights Reserved. * * The contents of this file are subject to the Erlang Public License, * Version 1.1, (the "License"); you may not use this file except in @@ -34,7 +34,7 @@ typedef struct { erts_cpu_info_t *erts_cpu_info_create(void); void erts_cpu_info_destroy(erts_cpu_info_t *cpuinfo); -void erts_cpu_info_update(erts_cpu_info_t *cpuinfo); +int erts_cpu_info_update(erts_cpu_info_t *cpuinfo); int erts_get_cpu_configured(erts_cpu_info_t *cpuinfo); int erts_get_cpu_online(erts_cpu_info_t *cpuinfo); int erts_get_cpu_available(erts_cpu_info_t *cpuinfo); 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 # 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; -- cgit v1.2.3