Re: CPU Hotplugging disabled, still cpuhp/%d threads running in my 32-bit system
Thank you very much Thomas, really. Enrico Enrico Mioso Mobile Phone Number: +393807096934 ( +Telegram :) ) My Tox ID is: 7C593F402A3C8632D87AB4B948D492294C39A6A614464ECF843CA3429FB023284180472C7475 I like / recommend the usage of open messaging standards. On Wed, 11 Jan 2017, Thomas Gleixner wrote: Date: Wed, 11 Jan 2017 10:16:10 From: Thomas Gleixner <t...@linutronix.de> To: Enrico Mioso <mrkiko...@gmail.com> Cc: linux-kernel@vger.kernel.org, Boris Ostrovsky <boris.ostrov...@oracle.com>, Rasmus Villemoes <li...@rasmusvillemoes.dk>, Peter Zijlstra <pet...@infradead.org>, Anna-Maria Gleixner <anna-ma...@linutronix.de>, Ingo Molnar <mi...@kernel.org>, Sebastian Andrzej Siewior <bige...@linutronix.de> Subject: Re: CPU Hotplugging disabled, still cpuhp/%d threads running in my 32-bit system On Tue, 10 Jan 2017, Enrico Mioso wrote: Hello guys. I disabled CPU hotplugging in my .config: still I can see what follows in the process list. 11 ?S 0:00 [cpuhp/0] 12 ?S 0:00 [cpuhp/1] And from what I can see in kernel/cpu.c:574, this is related to CPU hotplugging. Is this normal? And, out of curiosity, why? Yes. We need the threads for bringing up the CPUs and for modules and other functionality to set up per cpu related things. The thread makes sure that the code runs on the CPUs and handles the functionality related to install/remove of hotplug callbacks. Thanks, tglx
Re: CPU Hotplugging disabled, still cpuhp/%d threads running in my 32-bit system
Thank you very much Thomas, really. Enrico Enrico Mioso Mobile Phone Number: +393807096934 ( +Telegram :) ) My Tox ID is: 7C593F402A3C8632D87AB4B948D492294C39A6A614464ECF843CA3429FB023284180472C7475 I like / recommend the usage of open messaging standards. On Wed, 11 Jan 2017, Thomas Gleixner wrote: Date: Wed, 11 Jan 2017 10:16:10 From: Thomas Gleixner To: Enrico Mioso Cc: linux-kernel@vger.kernel.org, Boris Ostrovsky , Rasmus Villemoes , Peter Zijlstra , Anna-Maria Gleixner , Ingo Molnar , Sebastian Andrzej Siewior Subject: Re: CPU Hotplugging disabled, still cpuhp/%d threads running in my 32-bit system On Tue, 10 Jan 2017, Enrico Mioso wrote: Hello guys. I disabled CPU hotplugging in my .config: still I can see what follows in the process list. 11 ?S 0:00 [cpuhp/0] 12 ?S 0:00 [cpuhp/1] And from what I can see in kernel/cpu.c:574, this is related to CPU hotplugging. Is this normal? And, out of curiosity, why? Yes. We need the threads for bringing up the CPUs and for modules and other functionality to set up per cpu related things. The thread makes sure that the code runs on the CPUs and handles the functionality related to install/remove of hotplug callbacks. Thanks, tglx
Re: CPU Hotplugging disabled, still cpuhp/%d threads running in my 32-bit system
On Tue, 10 Jan 2017, Enrico Mioso wrote: > Hello guys. > I disabled CPU hotplugging in my .config: still I can see what follows in the > process list. > >11 ?S 0:00 [cpuhp/0] >12 ?S 0:00 [cpuhp/1] > > And from what I can see in kernel/cpu.c:574, this is related to CPU > hotplugging. > Is this normal? And, out of curiosity, why? Yes. We need the threads for bringing up the CPUs and for modules and other functionality to set up per cpu related things. The thread makes sure that the code runs on the CPUs and handles the functionality related to install/remove of hotplug callbacks. Thanks, tglx
Re: CPU Hotplugging disabled, still cpuhp/%d threads running in my 32-bit system
On Tue, 10 Jan 2017, Enrico Mioso wrote: > Hello guys. > I disabled CPU hotplugging in my .config: still I can see what follows in the > process list. > >11 ?S 0:00 [cpuhp/0] >12 ?S 0:00 [cpuhp/1] > > And from what I can see in kernel/cpu.c:574, this is related to CPU > hotplugging. > Is this normal? And, out of curiosity, why? Yes. We need the threads for bringing up the CPUs and for modules and other functionality to set up per cpu related things. The thread makes sure that the code runs on the CPUs and handles the functionality related to install/remove of hotplug callbacks. Thanks, tglx
CPU Hotplugging disabled, still cpuhp/%d threads running in my 32-bit system
Hello guys. I disabled CPU hotplugging in my .config: still I can see what follows in the process list. 11 ?S 0:00 [cpuhp/0] 12 ?S 0:00 [cpuhp/1] And from what I can see in kernel/cpu.c:574, this is related to CPU hotplugging. Is this normal? And, out of curiosity, why? Running current branch (git) kernel, commit 2cfe8f8290bd28cf1ee67db914a6e76cf8e6437b . Thank you all guys, for your replies and everything, in advance. Enrico My .config: # # Automatically generated file; DO NOT EDIT. # Linux/x86 4.10.0-rc3 Kernel Configuration # # CONFIG_64BIT is not set CONFIG_X86_32=y CONFIG_X86=y CONFIG_INSTRUCTION_DECODER=y CONFIG_OUTPUT_FORMAT="elf32-i386" CONFIG_ARCH_DEFCONFIG="arch/x86/configs/i386_defconfig" CONFIG_LOCKDEP_SUPPORT=y CONFIG_STACKTRACE_SUPPORT=y CONFIG_MMU=y CONFIG_ARCH_MMAP_RND_BITS_MIN=8 CONFIG_ARCH_MMAP_RND_BITS_MAX=16 CONFIG_ARCH_MMAP_RND_COMPAT_BITS_MIN=8 CONFIG_ARCH_MMAP_RND_COMPAT_BITS_MAX=16 CONFIG_NEED_SG_DMA_LENGTH=y CONFIG_GENERIC_ISA_DMA=y CONFIG_GENERIC_BUG=y CONFIG_GENERIC_HWEIGHT=y CONFIG_ARCH_MAY_HAVE_PC_FDC=y CONFIG_RWSEM_XCHGADD_ALGORITHM=y CONFIG_GENERIC_CALIBRATE_DELAY=y CONFIG_ARCH_HAS_CPU_RELAX=y CONFIG_ARCH_HAS_CACHE_LINE_SIZE=y CONFIG_HAVE_SETUP_PER_CPU_AREA=y CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK=y CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK=y CONFIG_ARCH_HIBERNATION_POSSIBLE=y CONFIG_ARCH_SUSPEND_POSSIBLE=y CONFIG_ARCH_WANT_HUGE_PMD_SHARE=y CONFIG_ARCH_WANT_GENERAL_HUGETLB=y CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING=y CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC=y CONFIG_X86_32_SMP=y CONFIG_ARCH_SUPPORTS_UPROBES=y CONFIG_FIX_EARLYCON_MEM=y CONFIG_DEBUG_RODATA=y CONFIG_PGTABLE_LEVELS=2 CONFIG_DEFCONFIG_LIST="/lib/modules/$UNAME_RELEASE/.config" CONFIG_IRQ_WORK=y CONFIG_BUILDTIME_EXTABLE_SORT=y CONFIG_THREAD_INFO_IN_TASK=y # # General setup # CONFIG_INIT_ENV_ARG_LIMIT=32 CONFIG_CROSS_COMPILE="" # CONFIG_COMPILE_TEST is not set CONFIG_LOCALVERSION="ho" # CONFIG_LOCALVERSION_AUTO is not set CONFIG_HAVE_KERNEL_GZIP=y CONFIG_HAVE_KERNEL_BZIP2=y CONFIG_HAVE_KERNEL_LZMA=y CONFIG_HAVE_KERNEL_XZ=y CONFIG_HAVE_KERNEL_LZO=y CONFIG_HAVE_KERNEL_LZ4=y # CONFIG_KERNEL_GZIP is not set # CONFIG_KERNEL_BZIP2 is not set # CONFIG_KERNEL_LZMA is not set CONFIG_KERNEL_XZ=y # CONFIG_KERNEL_LZO is not set # CONFIG_KERNEL_LZ4 is not set CONFIG_DEFAULT_HOSTNAME="(gato-saldo)" CONFIG_SWAP=y CONFIG_SYSVIPC=y CONFIG_SYSVIPC_SYSCTL=y # CONFIG_POSIX_MQUEUE is not set CONFIG_CROSS_MEMORY_ATTACH=y CONFIG_FHANDLE=y # CONFIG_USELIB is not set # CONFIG_AUDIT is not set CONFIG_HAVE_ARCH_AUDITSYSCALL=y # # IRQ subsystem # CONFIG_GENERIC_IRQ_PROBE=y CONFIG_GENERIC_IRQ_SHOW=y CONFIG_GENERIC_PENDING_IRQ=y CONFIG_IRQ_DOMAIN=y CONFIG_IRQ_DOMAIN_HIERARCHY=y CONFIG_GENERIC_MSI_IRQ=y CONFIG_GENERIC_MSI_IRQ_DOMAIN=y # CONFIG_IRQ_DOMAIN_DEBUG is not set CONFIG_IRQ_FORCED_THREADING=y CONFIG_SPARSE_IRQ=y CONFIG_CLOCKSOURCE_WATCHDOG=y CONFIG_ARCH_CLOCKSOURCE_DATA=y CONFIG_CLOCKSOURCE_VALIDATE_LAST_CYCLE=y CONFIG_GENERIC_TIME_VSYSCALL=y CONFIG_GENERIC_CLOCKEVENTS=y CONFIG_GENERIC_CLOCKEVENTS_BROADCAST=y CONFIG_GENERIC_CLOCKEVENTS_MIN_ADJUST=y CONFIG_GENERIC_CMOS_UPDATE=y # # Timers subsystem # CONFIG_TICK_ONESHOT=y CONFIG_NO_HZ_COMMON=y # CONFIG_HZ_PERIODIC is not set CONFIG_NO_HZ_IDLE=y # CONFIG_NO_HZ is not set CONFIG_HIGH_RES_TIMERS=y # # CPU/Task time and stats accounting # CONFIG_TICK_CPU_ACCOUNTING=y # CONFIG_IRQ_TIME_ACCOUNTING is not set CONFIG_BSD_PROCESS_ACCT=y CONFIG_BSD_PROCESS_ACCT_V3=y CONFIG_TASKSTATS=y CONFIG_TASK_DELAY_ACCT=y # CONFIG_TASK_XACCT is not set # # RCU Subsystem # CONFIG_TREE_RCU=y # CONFIG_RCU_EXPERT is not set CONFIG_SRCU=y # CONFIG_TASKS_RCU is not set CONFIG_RCU_STALL_COMMON=y CONFIG_TREE_RCU_TRACE=y # CONFIG_RCU_EXPEDITE_BOOT is not set CONFIG_BUILD_BIN2C=y CONFIG_IKCONFIG=m CONFIG_IKCONFIG_PROC=y CONFIG_LOG_BUF_SHIFT=18 CONFIG_LOG_CPU_MAX_BUF_SHIFT=12 CONFIG_NMI_LOG_BUF_SHIFT=13 CONFIG_HAVE_UNSTABLE_SCHED_CLOCK=y CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH=y CONFIG_CGROUPS=y CONFIG_PAGE_COUNTER=y CONFIG_MEMCG=y CONFIG_MEMCG_SWAP=y # CONFIG_MEMCG_SWAP_ENABLED is not set # CONFIG_BLK_CGROUP is not set # CONFIG_CGROUP_SCHED is not set CONFIG_CGROUP_PIDS=y # CONFIG_CGROUP_FREEZER is not set CONFIG_CGROUP_HUGETLB=y # CONFIG_CPUSETS is not set # CONFIG_CGROUP_DEVICE is not set CONFIG_CGROUP_CPUACCT=y # CONFIG_CGROUP_PERF is not set CONFIG_CGROUP_BPF=y # CONFIG_CGROUP_DEBUG is not set # CONFIG_CHECKPOINT_RESTORE is not set CONFIG_NAMESPACES=y CONFIG_UTS_NS=y CONFIG_IPC_NS=y CONFIG_USER_NS=y CONFIG_PID_NS=y CONFIG_NET_NS=y # CONFIG_SCHED_AUTOGROUP is not set # CONFIG_SYSFS_DEPRECATED is not set CONFIG_RELAY=y # CONFIG_BLK_DEV_INITRD is not set CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE=y # CONFIG_CC_OPTIMIZE_FOR_SIZE is not set CONFIG_SYSCTL=y CONFIG_ANON_INODES=y CONFIG_HAVE_UID16=y CONFIG_SYSCTL_EXCEPTION_TRACE=y CONFIG_HAVE_PCSPKR_PLATFORM=y CONFIG_BPF=y CONFIG_EXPERT=y # CONFIG_UID16 is not set CONFIG_MULTIUSER=y # CONFIG_SGETMASK_SYSCALL is not set # CONFIG_SYSFS_SYSCALL is not
CPU Hotplugging disabled, still cpuhp/%d threads running in my 32-bit system
Hello guys. I disabled CPU hotplugging in my .config: still I can see what follows in the process list. 11 ?S 0:00 [cpuhp/0] 12 ?S 0:00 [cpuhp/1] And from what I can see in kernel/cpu.c:574, this is related to CPU hotplugging. Is this normal? And, out of curiosity, why? Running current branch (git) kernel, commit 2cfe8f8290bd28cf1ee67db914a6e76cf8e6437b . Thank you all guys, for your replies and everything, in advance. Enrico My .config: # # Automatically generated file; DO NOT EDIT. # Linux/x86 4.10.0-rc3 Kernel Configuration # # CONFIG_64BIT is not set CONFIG_X86_32=y CONFIG_X86=y CONFIG_INSTRUCTION_DECODER=y CONFIG_OUTPUT_FORMAT="elf32-i386" CONFIG_ARCH_DEFCONFIG="arch/x86/configs/i386_defconfig" CONFIG_LOCKDEP_SUPPORT=y CONFIG_STACKTRACE_SUPPORT=y CONFIG_MMU=y CONFIG_ARCH_MMAP_RND_BITS_MIN=8 CONFIG_ARCH_MMAP_RND_BITS_MAX=16 CONFIG_ARCH_MMAP_RND_COMPAT_BITS_MIN=8 CONFIG_ARCH_MMAP_RND_COMPAT_BITS_MAX=16 CONFIG_NEED_SG_DMA_LENGTH=y CONFIG_GENERIC_ISA_DMA=y CONFIG_GENERIC_BUG=y CONFIG_GENERIC_HWEIGHT=y CONFIG_ARCH_MAY_HAVE_PC_FDC=y CONFIG_RWSEM_XCHGADD_ALGORITHM=y CONFIG_GENERIC_CALIBRATE_DELAY=y CONFIG_ARCH_HAS_CPU_RELAX=y CONFIG_ARCH_HAS_CACHE_LINE_SIZE=y CONFIG_HAVE_SETUP_PER_CPU_AREA=y CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK=y CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK=y CONFIG_ARCH_HIBERNATION_POSSIBLE=y CONFIG_ARCH_SUSPEND_POSSIBLE=y CONFIG_ARCH_WANT_HUGE_PMD_SHARE=y CONFIG_ARCH_WANT_GENERAL_HUGETLB=y CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING=y CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC=y CONFIG_X86_32_SMP=y CONFIG_ARCH_SUPPORTS_UPROBES=y CONFIG_FIX_EARLYCON_MEM=y CONFIG_DEBUG_RODATA=y CONFIG_PGTABLE_LEVELS=2 CONFIG_DEFCONFIG_LIST="/lib/modules/$UNAME_RELEASE/.config" CONFIG_IRQ_WORK=y CONFIG_BUILDTIME_EXTABLE_SORT=y CONFIG_THREAD_INFO_IN_TASK=y # # General setup # CONFIG_INIT_ENV_ARG_LIMIT=32 CONFIG_CROSS_COMPILE="" # CONFIG_COMPILE_TEST is not set CONFIG_LOCALVERSION="ho" # CONFIG_LOCALVERSION_AUTO is not set CONFIG_HAVE_KERNEL_GZIP=y CONFIG_HAVE_KERNEL_BZIP2=y CONFIG_HAVE_KERNEL_LZMA=y CONFIG_HAVE_KERNEL_XZ=y CONFIG_HAVE_KERNEL_LZO=y CONFIG_HAVE_KERNEL_LZ4=y # CONFIG_KERNEL_GZIP is not set # CONFIG_KERNEL_BZIP2 is not set # CONFIG_KERNEL_LZMA is not set CONFIG_KERNEL_XZ=y # CONFIG_KERNEL_LZO is not set # CONFIG_KERNEL_LZ4 is not set CONFIG_DEFAULT_HOSTNAME="(gato-saldo)" CONFIG_SWAP=y CONFIG_SYSVIPC=y CONFIG_SYSVIPC_SYSCTL=y # CONFIG_POSIX_MQUEUE is not set CONFIG_CROSS_MEMORY_ATTACH=y CONFIG_FHANDLE=y # CONFIG_USELIB is not set # CONFIG_AUDIT is not set CONFIG_HAVE_ARCH_AUDITSYSCALL=y # # IRQ subsystem # CONFIG_GENERIC_IRQ_PROBE=y CONFIG_GENERIC_IRQ_SHOW=y CONFIG_GENERIC_PENDING_IRQ=y CONFIG_IRQ_DOMAIN=y CONFIG_IRQ_DOMAIN_HIERARCHY=y CONFIG_GENERIC_MSI_IRQ=y CONFIG_GENERIC_MSI_IRQ_DOMAIN=y # CONFIG_IRQ_DOMAIN_DEBUG is not set CONFIG_IRQ_FORCED_THREADING=y CONFIG_SPARSE_IRQ=y CONFIG_CLOCKSOURCE_WATCHDOG=y CONFIG_ARCH_CLOCKSOURCE_DATA=y CONFIG_CLOCKSOURCE_VALIDATE_LAST_CYCLE=y CONFIG_GENERIC_TIME_VSYSCALL=y CONFIG_GENERIC_CLOCKEVENTS=y CONFIG_GENERIC_CLOCKEVENTS_BROADCAST=y CONFIG_GENERIC_CLOCKEVENTS_MIN_ADJUST=y CONFIG_GENERIC_CMOS_UPDATE=y # # Timers subsystem # CONFIG_TICK_ONESHOT=y CONFIG_NO_HZ_COMMON=y # CONFIG_HZ_PERIODIC is not set CONFIG_NO_HZ_IDLE=y # CONFIG_NO_HZ is not set CONFIG_HIGH_RES_TIMERS=y # # CPU/Task time and stats accounting # CONFIG_TICK_CPU_ACCOUNTING=y # CONFIG_IRQ_TIME_ACCOUNTING is not set CONFIG_BSD_PROCESS_ACCT=y CONFIG_BSD_PROCESS_ACCT_V3=y CONFIG_TASKSTATS=y CONFIG_TASK_DELAY_ACCT=y # CONFIG_TASK_XACCT is not set # # RCU Subsystem # CONFIG_TREE_RCU=y # CONFIG_RCU_EXPERT is not set CONFIG_SRCU=y # CONFIG_TASKS_RCU is not set CONFIG_RCU_STALL_COMMON=y CONFIG_TREE_RCU_TRACE=y # CONFIG_RCU_EXPEDITE_BOOT is not set CONFIG_BUILD_BIN2C=y CONFIG_IKCONFIG=m CONFIG_IKCONFIG_PROC=y CONFIG_LOG_BUF_SHIFT=18 CONFIG_LOG_CPU_MAX_BUF_SHIFT=12 CONFIG_NMI_LOG_BUF_SHIFT=13 CONFIG_HAVE_UNSTABLE_SCHED_CLOCK=y CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH=y CONFIG_CGROUPS=y CONFIG_PAGE_COUNTER=y CONFIG_MEMCG=y CONFIG_MEMCG_SWAP=y # CONFIG_MEMCG_SWAP_ENABLED is not set # CONFIG_BLK_CGROUP is not set # CONFIG_CGROUP_SCHED is not set CONFIG_CGROUP_PIDS=y # CONFIG_CGROUP_FREEZER is not set CONFIG_CGROUP_HUGETLB=y # CONFIG_CPUSETS is not set # CONFIG_CGROUP_DEVICE is not set CONFIG_CGROUP_CPUACCT=y # CONFIG_CGROUP_PERF is not set CONFIG_CGROUP_BPF=y # CONFIG_CGROUP_DEBUG is not set # CONFIG_CHECKPOINT_RESTORE is not set CONFIG_NAMESPACES=y CONFIG_UTS_NS=y CONFIG_IPC_NS=y CONFIG_USER_NS=y CONFIG_PID_NS=y CONFIG_NET_NS=y # CONFIG_SCHED_AUTOGROUP is not set # CONFIG_SYSFS_DEPRECATED is not set CONFIG_RELAY=y # CONFIG_BLK_DEV_INITRD is not set CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE=y # CONFIG_CC_OPTIMIZE_FOR_SIZE is not set CONFIG_SYSCTL=y CONFIG_ANON_INODES=y CONFIG_HAVE_UID16=y CONFIG_SYSCTL_EXCEPTION_TRACE=y CONFIG_HAVE_PCSPKR_PLATFORM=y CONFIG_BPF=y CONFIG_EXPERT=y # CONFIG_UID16 is not set CONFIG_MULTIUSER=y # CONFIG_SGETMASK_SYSCALL is not set # CONFIG_SYSFS_SYSCALL is not
