diff options
Diffstat (limited to 'init')
| -rw-r--r-- | init/Kconfig | 111 | ||||
| -rw-r--r-- | init/do_mounts.c | 61 | ||||
| -rw-r--r-- | init/main.c | 4 |
3 files changed, 131 insertions, 45 deletions
diff --git a/init/Kconfig b/init/Kconfig index 38c1a1d0bf3..675d8a2326c 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -486,35 +486,35 @@ config PREEMPT_RCU This option enables preemptible-RCU code that is common between the TREE_PREEMPT_RCU and TINY_PREEMPT_RCU implementations. +config CONTEXT_TRACKING + bool + config RCU_USER_QS bool "Consider userspace as in RCU extended quiescent state" - depends on HAVE_RCU_USER_QS && SMP + depends on HAVE_CONTEXT_TRACKING && SMP + select CONTEXT_TRACKING help This option sets hooks on kernel / userspace boundaries and puts RCU in extended quiescent state when the CPU runs in userspace. It means that when a CPU runs in userspace, it is excluded from the global RCU state machine and thus doesn't - to keep the timer tick on for RCU. + try to keep the timer tick on for RCU. Unless you want to hack and help the development of the full - tickless feature, you shouldn't enable this option. It adds - unnecessary overhead. + dynticks mode, you shouldn't enable this option. It also + adds unnecessary overhead. If unsure say N -config RCU_USER_QS_FORCE - bool "Force userspace extended QS by default" - depends on RCU_USER_QS +config CONTEXT_TRACKING_FORCE + bool "Force context tracking" + depends on CONTEXT_TRACKING help - Set the hooks in user/kernel boundaries by default in order to - test this feature that treats userspace as an extended quiescent - state until we have a real user like a full adaptive nohz option. - - Unless you want to hack and help the development of the full - tickless feature, you shouldn't enable this option. It adds - unnecessary overhead. - - If unsure say N + Probe on user/kernel boundaries by default in order to + test the features that rely on it such as userspace RCU extended + quiescent states. + This test is there for debugging until we have a real user like the + full dynticks mode. config RCU_FANOUT int "Tree-based hierarchical RCU fanout value" @@ -582,14 +582,13 @@ config RCU_FAST_NO_HZ depends on NO_HZ && SMP default n help - This option causes RCU to attempt to accelerate grace periods - in order to allow CPUs to enter dynticks-idle state more - quickly. On the other hand, this option increases the overhead - of the dynticks-idle checking, particularly on systems with - large numbers of CPUs. + This option causes RCU to attempt to accelerate grace periods in + order to allow CPUs to enter dynticks-idle state more quickly. + On the other hand, this option increases the overhead of the + dynticks-idle checking, thus degrading scheduling latency. - Say Y if energy efficiency is critically important, particularly - if you have relatively few CPUs. + Say Y if energy efficiency is critically important, and you don't + care about real-time response. Say N if you are unsure. @@ -655,6 +654,28 @@ config RCU_BOOST_DELAY Accept the default if unsure. +config RCU_NOCB_CPU + bool "Offload RCU callback processing from boot-selected CPUs" + depends on TREE_RCU || TREE_PREEMPT_RCU + default n + help + Use this option to reduce OS jitter for aggressive HPC or + real-time workloads. It can also be used to offload RCU + callback invocation to energy-efficient CPUs in battery-powered + asymmetric multiprocessors. + + This option offloads callback invocation from the set of + CPUs specified at boot time by the rcu_nocbs parameter. + For each such CPU, a kthread ("rcuoN") will be created to + invoke callbacks, where the "N" is the CPU being offloaded. + Nothing prevents this kthread from running on the specified + CPUs, but (1) the kthreads may be preempted between each + callback, and (2) affinity or cgroups can be used to force + the kthreads to run on whatever set of CPUs is desired. + + Say Y here if you want reduced OS jitter on selected CPUs. + Say N here if you are unsure. + endmenu # "RCU Subsystem" config IKCONFIG @@ -696,6 +717,50 @@ config LOG_BUF_SHIFT config HAVE_UNSTABLE_SCHED_CLOCK bool +# +# For architectures that want to enable the support for NUMA-affine scheduler +# balancing logic: +# +config ARCH_SUPPORTS_NUMA_BALANCING + bool + +# For architectures that (ab)use NUMA to represent different memory regions +# all cpu-local but of different latencies, such as SuperH. +# +config ARCH_WANT_NUMA_VARIABLE_LOCALITY + bool + +# +# For architectures that are willing to define _PAGE_NUMA as _PAGE_PROTNONE +config ARCH_WANTS_PROT_NUMA_PROT_NONE + bool + +config ARCH_USES_NUMA_PROT_NONE + bool + default y + depends on ARCH_WANTS_PROT_NUMA_PROT_NONE + depends on NUMA_BALANCING + +config NUMA_BALANCING_DEFAULT_ENABLED + bool "Automatically enable NUMA aware memory/task placement" + default y + depends on NUMA_BALANCING + help + If set, autonumic NUMA balancing will be enabled if running on a NUMA + machine. + +config NUMA_BALANCING + bool "Memory placement aware NUMA scheduler" + depends on ARCH_SUPPORTS_NUMA_BALANCING + depends on !ARCH_WANT_NUMA_VARIABLE_LOCALITY + depends on SMP && NUMA && MIGRATION + help + This option adds support for automatic NUMA aware memory/task placement. + The mechanism is quite primitive and is based on migrating memory when + it is references to the node the task is running on. + + This system will be inactive on UMA systems. + menuconfig CGROUPS boolean "Control Group support" depends on EVENTFD diff --git a/init/do_mounts.c b/init/do_mounts.c index f8a66424360..1d1b6348f90 100644 --- a/init/do_mounts.c +++ b/init/do_mounts.c @@ -69,23 +69,28 @@ __setup("ro", readonly); __setup("rw", readwrite); #ifdef CONFIG_BLOCK +struct uuidcmp { + const char *uuid; + int len; +}; + /** * match_dev_by_uuid - callback for finding a partition using its uuid * @dev: device passed in by the caller - * @data: opaque pointer to a 36 byte char array with a UUID + * @data: opaque pointer to the desired struct uuidcmp to match * * Returns 1 if the device matches, and 0 otherwise. */ static int match_dev_by_uuid(struct device *dev, void *data) { - u8 *uuid = data; + struct uuidcmp *cmp = data; struct hd_struct *part = dev_to_part(dev); if (!part->info) goto no_match; - if (memcmp(uuid, part->info->uuid, sizeof(part->info->uuid))) - goto no_match; + if (strncasecmp(cmp->uuid, part->info->uuid, cmp->len)) + goto no_match; return 1; no_match: @@ -95,7 +100,7 @@ no_match: /** * devt_from_partuuid - looks up the dev_t of a partition by its UUID - * @uuid: min 36 byte char array containing a hex ascii UUID + * @uuid: char array containing ascii UUID * * The function will return the first partition which contains a matching * UUID value in its partition_meta_info struct. This does not search @@ -106,38 +111,41 @@ no_match: * * Returns the matching dev_t on success or 0 on failure. */ -static dev_t devt_from_partuuid(char *uuid_str) +static dev_t devt_from_partuuid(const char *uuid_str) { dev_t res = 0; + struct uuidcmp cmp; struct device *dev = NULL; - u8 uuid[16]; struct gendisk *disk; struct hd_struct *part; int offset = 0; + bool clear_root_wait = false; + char *slash; - if (strlen(uuid_str) < 36) - goto done; + cmp.uuid = uuid_str; + slash = strchr(uuid_str, '/'); /* Check for optional partition number offset attributes. */ - if (uuid_str[36]) { + if (slash) { char c = 0; /* Explicitly fail on poor PARTUUID syntax. */ - if (sscanf(&uuid_str[36], - "/PARTNROFF=%d%c", &offset, &c) != 1) { - printk(KERN_ERR "VFS: PARTUUID= is invalid.\n" - "Expected PARTUUID=<valid-uuid-id>[/PARTNROFF=%%d]\n"); - if (root_wait) - printk(KERN_ERR - "Disabling rootwait; root= is invalid.\n"); - root_wait = 0; + if (sscanf(slash + 1, + "PARTNROFF=%d%c", &offset, &c) != 1) { + clear_root_wait = true; goto done; } + cmp.len = slash - uuid_str; + } else { + cmp.len = strlen(uuid_str); } - /* Pack the requested UUID in the expected format. */ - part_pack_uuid(uuid_str, uuid); + if (!cmp.len) { + clear_root_wait = true; + goto done; + } - dev = class_find_device(&block_class, NULL, uuid, &match_dev_by_uuid); + dev = class_find_device(&block_class, NULL, &cmp, + &match_dev_by_uuid); if (!dev) goto done; @@ -158,6 +166,13 @@ static dev_t devt_from_partuuid(char *uuid_str) no_offset: put_device(dev); done: + if (clear_root_wait) { + pr_err("VFS: PARTUUID= is invalid.\n" + "Expected PARTUUID=<valid-uuid-id>[/PARTNROFF=%%d]\n"); + if (root_wait) + pr_err("Disabling rootwait; root= is invalid.\n"); + root_wait = 0; + } return res; } #endif @@ -174,6 +189,10 @@ done: * used when disk name of partitioned disk ends on a digit. * 6) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the * unique id of a partition if the partition table provides it. + * The UUID may be either an EFI/GPT UUID, or refer to an MSDOS + * partition using the format SSSSSSSS-PP, where SSSSSSSS is a zero- + * filled hex representation of the 32-bit "NT disk signature", and PP + * is a zero-filled hex representation of the 1-based partition number. * 7) PARTUUID=<UUID>/PARTNROFF=<int> to select a partition in relation to * a partition with a known unique id. * diff --git a/init/main.c b/init/main.c index 317750a18f7..baf1f0f5c46 100644 --- a/init/main.c +++ b/init/main.c @@ -442,9 +442,11 @@ void __init __weak smp_setup_processor_id(void) { } +# if THREAD_SIZE >= PAGE_SIZE void __init __weak thread_info_cache_init(void) { } +#endif /* * Set up kernel memory allocators @@ -854,7 +856,7 @@ static void __init kernel_init_freeable(void) /* * init can allocate pages on any node */ - set_mems_allowed(node_states[N_HIGH_MEMORY]); + set_mems_allowed(node_states[N_MEMORY]); /* * init can run on any cpu. */ |