linux/kernel
Paul E. McKenney 04f34650ca rcu: Fix CONFIG_RCU_FANOUT_EXACT for odd fanout/leaf values
Each element of the rcu_state structure's ->levelspread[] array
is intended to contain the per-level fanout, where the zero-th
element corresponds to the root of the rcu_node tree, and the last
element corresponds to the leaves.  In the CONFIG_RCU_FANOUT_EXACT
case, this means that the last element should be filled in
from CONFIG_RCU_FANOUT_LEAF (or from the rcu_fanout_leaf boot
parameter, if provided) and that the remaining elements should
be filled in from CONFIG_RCU_FANOUT.  Unfortunately, the current
code in rcu_init_levelspread() takes the opposite approach, placing
CONFIG_RCU_FANOUT_LEAF in the zero-th element and CONFIG_RCU_FANOUT in
the remaining elements.

For typical power-of-two values, this generates odd but functional
rcu_node trees.  However, other values, for example CONFIG_RCU_FANOUT=3
and CONFIG_RCU_FANOUT_LEAF=2, generate trees that can leave some CPUs
out of the grace-period computation, resulting in too-short grace periods
and therefore a broken RCU implementation.

This commit therefore fixes rcu_init_levelspread() to set the last
->levelspread[] array element from CONFIG_RCU_FANOUT_LEAF and the
remaining elements from CONFIG_RCU_FANOUT, thus generating the
intended rcu_node trees.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2013-12-09 15:12:38 -08:00
..
cpu sched: Add NEED_RESCHED to the preempt_count 2013-09-25 14:07:49 +02:00
debug kdb: Add support for external NMI handler to call KGDB/KDB 2013-10-03 18:47:54 +02:00
events list: introduce list_next_entry() and list_prev_entry() 2013-11-13 12:09:23 +09:00
gcov gcov: reuse kbasename helper 2013-11-13 12:09:34 +09:00
irq Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-11-19 10:40:00 -08:00
locking locking/lockdep: Mark __lockdep_count_forward_deps() as static 2013-11-13 13:50:17 +01:00
power Merge branch 'pm-sleep' 2013-11-19 01:07:08 +01:00
printk printk.c: comments should refer to /proc/vmcore instead of /proc/vmcoreinfo 2013-11-13 12:09:14 +09:00
rcu rcu: Fix CONFIG_RCU_FANOUT_EXACT for odd fanout/leaf values 2013-12-09 15:12:38 -08:00
sched sched/fair: Avoid integer overflow 2013-11-13 13:33:55 +01:00
time Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-11-12 10:36:00 +09:00
trace ftrace: Fix function graph with loading of modules 2013-11-26 10:36:50 -05:00
.gitignore kernel/hz.bc: ignore. 2013-04-22 07:09:06 -07:00
acct.c fs: Fix hang with BSD accounting on frozen filesystem 2013-05-04 14:57:58 -04:00
async.c
audit_tree.c kernel/audit_tree.c:audit_add_tree_rule(): protect `rule' from kill_rules() 2013-06-12 16:29:46 -07:00
audit_watch.c
audit.c Merge git://git.infradead.org/users/eparis/audit 2013-11-21 19:18:14 -08:00
audit.h audit: call audit_bprm() only once to add AUDIT_EXECVE information 2013-11-05 11:15:03 -05:00
auditfilter.c audit: do not reject all AUDIT_INODE filter types 2013-11-05 11:09:16 -05:00
auditsc.c audit: fix type of sessionid in audit_set_loginuid() 2013-11-06 11:47:24 -05:00
backtracetest.c
bounds.c kernel/bounds: avoid circular dependencies in generated headers 2013-11-19 14:20:12 -08:00
capability.c xfs: update for v3.12-rc1 2013-09-09 11:19:09 -07:00
cgroup_freezer.c cgroup: make css_for_each_descendant() and friends include the origin css in the iteration 2013-08-08 20:11:27 -04:00
cgroup.c cgroup: fix cgroup_subsys_state leak for seq_files 2013-11-27 18:16:21 -05:00
compat.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2013-05-01 07:21:43 -07:00
configs.c proc: Supply PDE attribute setting accessor functions 2013-05-01 17:29:18 -04:00
context_tracking.c Linux 3.12-rc4 2013-10-09 12:36:13 +02:00
cpu_pm.c
cpu.c Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-11-14 16:55:11 +09:00
cpuset.c cpuset: Fix memory allocator deadlock 2013-11-27 13:52:47 -05:00
crash_dump.c
cred.c
delayacct.c kernel/delayacct.c: remove redundant checking in __delayacct_add_tsk() 2013-11-13 12:09:12 +09:00
dma.c
elfcore.c switch elf_core_write_extra_phdrs() to dump_emit() 2013-11-09 00:16:23 -05:00
exec_domain.c
exit.c ptrace: revert "Prepare to fix racy accesses on task breakpoints" 2013-07-09 10:33:26 -07:00
extable.c kernel/extable: fix address-checks for core_kernel and init areas 2013-11-28 09:49:41 -08:00
fork.c mm: implement split page table lock for PMD level 2013-11-15 09:32:15 +09:00
freezer.c freezer: set PF_SUSPEND_TASK flag on tasks that call freeze_processes 2013-07-30 14:05:06 +02:00
futex_compat.c
futex.c locking: Move the rtmutex code to kernel/locking/ 2013-11-06 09:23:59 +01:00
groups.c userns: Kill nsown_capable it makes the wrong thing easy 2013-08-30 23:44:11 -07:00
hrtimer.c kernel: delete __cpuinit usage from all core kernel files 2013-07-14 19:36:59 -04:00
hung_task.c Here are the 3.13 KVM changes. There was a lot of work on the PPC 2013-11-15 13:51:36 +09:00
irq_work.c
itimer.c
jump_label.c static_key: WARN on usage before jump_label_init was called 2013-10-19 19:45:35 -04:00
kallsyms.c kernel: kallsyms: memory override issue, need check destination buffer length 2013-04-15 15:17:26 +09:30
kcmp.c
Kconfig.freezer
Kconfig.hz kernel: remove CONFIG_USE_GENERIC_SMP_HELPERS 2013-11-15 09:32:22 +09:00
Kconfig.locks locking: Fix copy/paste errors of "ARCH_INLINE_*_UNLOCK_BH" 2013-05-28 08:50:00 +02:00
Kconfig.preempt
kexec.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2013-11-15 16:47:22 -08:00
kmod.c kernel/kmod.c: check for NULL in call_usermodehelper_exec() 2013-09-30 14:31:02 -07:00
kprobes.c kprobes: use KSYM_NAME_LEN to size identifier buffers 2013-11-13 12:09:26 +09:00
ksysfs.c kernel: replace strict_strto*() with kstrto*() 2013-09-12 15:38:03 -07:00
kthread.c kthread: make kthread_create() killable 2013-11-13 12:08:59 +09:00
latencytop.c
Makefile Merge branch 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2013-11-21 19:46:00 -08:00
module_signing.c keys: change asymmetric keys to use common hash definitions 2013-10-25 17:15:18 -04:00
module-internal.h KEYS: Separate the kernel signature checking keyring from module signing 2013-09-25 17:17:01 +01:00
module.c Mainly boring here, too. rmmod --wait finally removed, though. 2013-11-15 13:27:50 +09:00
notifier.c
nsproxy.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2013-09-07 14:35:32 -07:00
padata.c padata: make the sequence counter an atomic_t 2013-10-30 12:02:58 +08:00
panic.c kernel/panic.c: reduce 1 byte usage for print tainted buffer 2013-11-13 12:09:35 +09:00
params.c kernel/params: fix handling of signed integer types 2013-09-28 12:35:52 -07:00
pid_namespace.c pid_namespace: make freeing struct pid_namespace rcu-delayed 2013-10-24 23:43:29 -04:00
pid.c pidns: fix free_pid() to handle the first fork failure 2013-09-30 14:31:03 -07:00
posix-cpu-timers.c posix_timers: fix racy timer delta caching on task exit 2013-07-03 16:54:42 +02:00
posix-timers.c posix-timers: Remove unused variable 2013-04-18 12:51:19 +02:00
profile.c kernel: delete __cpuinit usage from all core kernel files 2013-07-14 19:36:59 -04:00
ptrace.c exec/ptrace: fix get_dumpable() incorrect tests 2013-11-13 12:09:33 +09:00
range.c range: Do not add new blank slot with add_range_with_merge 2013-06-18 11:32:10 -05:00
reboot.c kernel/reboot.c: re-enable the function of variable reboot_default 2013-09-24 17:00:26 -07:00
relay.c kernel: delete __cpuinit usage from all core kernel files 2013-07-14 19:36:59 -04:00
res_counter.c memcg: reduce function dereference 2013-09-12 15:38:02 -07:00
resource.c kernel/resource.c: remove the unneeded assignment in function __find_resource 2013-07-03 16:08:06 -07:00
seccomp.c
signal.c constify copy_siginfo_to_user{,32}() 2013-11-09 00:16:29 -05:00
smp.c kernel: fix generic_exec_single indentation 2013-11-15 09:32:22 +09:00
smpboot.c kernel: delete __cpuinit usage from all core kernel files 2013-07-14 19:36:59 -04:00
smpboot.h
softirq.c revert "softirq: Add support for triggering softirq work on softirqs" 2013-11-15 09:32:22 +09:00
stacktrace.c
stop_machine.c stop_machine: Fix race between stop_two_cpus() and stop_cpus() 2013-11-11 12:43:38 +01:00
sys_ni.c unify compat fanotify_mark(2), switch to COMPAT_SYSCALL_DEFINE 2013-05-09 13:46:38 -04:00
sys.c kernel/sys.c: remove obsolete #include <linux/kexec.h> 2013-11-13 12:09:13 +09:00
sysctl_binary.c kernel/sysctl_binary.c: use scnprintf() instead of snprintf() 2013-11-13 12:09:33 +09:00
sysctl.c Merge branch 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-11-14 16:30:30 +09:00
system_certificates.S kernel/system_certificate.S: use real contents instead of macro GLOBAL() 2013-10-30 12:58:00 +00:00
system_keyring.c KEYS: Make the system 'trusted' keyring viewable by userspace 2013-09-25 17:17:01 +01:00
task_work.c task_work: documentation 2013-09-11 15:58:27 -07:00
taskstats.c genetlink: only pass array to genl_register_family_with_ops() 2013-11-19 16:39:05 -05:00
test_kprobes.c kernel/: rename random32() to prandom_u32() 2013-04-29 18:28:42 -07:00
time.c sched: Rename sched.c as sched/core.c in comments and Documentation 2013-06-19 12:58:42 +02:00
timeconst.bc
timer.c sched: Introduce preempt_count accessor functions 2013-09-25 14:07:32 +02:00
tracepoint.c Tracing updates for Linux 3.10 2013-04-29 13:55:38 -07:00
tsacct.c
uid16.c userns: Kill nsown_capable it makes the wrong thing easy 2013-08-30 23:44:11 -07:00
up.c kernel: provide a __smp_call_function_single stub for !CONFIG_SMP 2013-11-15 09:32:22 +09:00
user_namespace.c KEYS: Add per-user_namespace registers for persistent per-UID kerberos caches 2013-09-24 10:35:19 +01:00
user-return-notifier.c
user.c KEYS: Add per-user_namespace registers for persistent per-UID kerberos caches 2013-09-24 10:35:19 +01:00
utsname_sysctl.c
utsname.c userns: Kill nsown_capable it makes the wrong thing easy 2013-08-30 23:44:11 -07:00
watchdog.c watchdog: update watchdog_thresh properly 2013-09-24 17:00:25 -07:00
workqueue_internal.h sched: Rename sched.c as sched/core.c in comments and Documentation 2013-06-19 12:58:42 +02:00
workqueue.c workqueue: fix pool ID allocation leakage and remove BUILD_BUG_ON() in init_workqueues 2013-11-22 18:14:47 -05:00