Linus Torvalds
8053871d0f
smp: Fix smp_call_function_single_async() locking ...
The current smp_function_call code suffers a number of problems, most
notably smp_call_function_single_async() is broken.
The problem is that flush_smp_call_function_queue() does csd_unlock()
_after_ calling csd->func(). This means that a caller cannot properly
synchronize the csd usage as it has to.
Change the code to release the csd before calling ->func() for the
async case, and put a WARN_ON_ONCE(csd->flags & CSD_FLAG_LOCK) in
smp_call_function_single_async() to warn us of improper serialization,
because any waiting there can results in deadlocks when called with
IRQs disabled.
Rename the (currently) unused WAIT flag to SYNCHRONOUS and (re)use it
such that we know what to do in flush_smp_call_function_queue().
Rework csd_{,un}lock() to use smp_load_acquire() / smp_store_release()
to avoid some full barriers while more clearly providing lock
semantics.
Finally move the csd maintenance out of generic_exec_single() into its
callers for clearer code.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[ Added changelog. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Rafael David Tinoco <inaddy@ubuntu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/CA+55aFz492bzLFhdbKN-Hygjcreup7CjMEYk3nTSfRWjppz-OA@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-17 09:57:52 +02:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
2015-01-27 13:55:36 -08:00
x86: Add "make tinyconfig" to configure the tiniest possible kernel
2014-08-08 16:30:24 -07:00
debug: prevent entering debug mode on panic/exception.
2015-02-19 12:39:03 -06:00
perf: Fix irq_work 'tail' recursion
2015-03-23 10:46:32 +01:00
kbuild,gcov: simplify kernel/gcov/Makefile more
2015-01-09 17:25:44 +01:00
genirq / PM: Add flag for shared NO_SUSPEND interrupt lines
2015-03-04 21:42:19 +01:00
livepatch: Fix subtle race with coming and going modules
2015-03-17 10:31:54 +01:00
lockdep: Make print_lock() robust against concurrent release
2015-04-17 09:42:14 +02:00
Revert "PM / hibernate: avoid unsafe pages in e820 reserved regions"
2015-04-07 01:13:23 +02:00
console: Fix console name size mismatch
2015-03-07 03:39:55 +01:00
Merge branches 'core-urgent-for-linus' and 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2015-02-21 10:36:06 -08:00
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2015-04-13 11:08:28 -07:00
timers/PM: Drop unnecessary braces from tick_freeze()
2015-04-03 15:15:52 +02:00
ftrace: Fix ftrace enable ordering of sysctl ftrace_enabled
2015-03-09 10:55:34 -04:00
new fs_pin killing logics
2015-01-25 23:17:28 -05:00
kernel/async.c: switch to pr_foo()
2014-10-09 22:26:04 -04:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
2014-12-30 10:45:47 -08:00
audit: replace getname()/putname() hacks with reference counters
2015-01-23 00:23:58 -05:00
fsnotify: unify inode and mount marks handling
2014-12-13 12:42:53 -08:00
audit: invalid op= values for rules
2014-09-23 16:37:53 -04:00
Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit
2015-02-11 20:07:47 -08:00
Merge branch 'getname2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2015-02-17 15:27:47 -08:00
page-cgroup: get rid of NR_PCG_FLAGS
2014-08-08 15:57:18 -07:00
kernfs: remove KERNFS_STATIC_NAME
2015-02-13 21:21:36 -08:00
all arches, signal: move restart_block to struct task_struct
2015-02-12 18:54:12 -08:00
sched: stop the unbound recursion in preempt_schedule_context()
2014-10-28 10:46:05 +01:00
clockevents: Cleanup dead cpu explicitely
2015-04-03 08:44:37 +02:00
cpuset: Fix cpuset sched_relax_domain_level
2015-03-02 11:55:04 -05:00
crash_dump: Make is_kdump_kernel() accessible from modules
2014-08-25 15:42:19 -07:00
oom, PM: make OOM detection in the freezer path raceless
2015-02-11 17:06:03 -08:00
ftrace/x86/extable: Add is_ftrace_trampoline() function
2014-11-19 15:25:26 -05:00
mm: do not use mm->nr_pmds on !MMU configurations
2015-02-12 18:54:10 -08:00
freezer: remove obsolete comments in __thaw_task()
2014-10-21 23:44:20 +02:00
Linux 34.0-rc1
2015-02-24 08:41:07 +01:00
userns: Don't allow setgroups until a gid mapping has been setablished
2014-12-09 16:58:40 -06:00
percpu: Convert remaining __get_cpu_var uses in 3.18-rcX
2014-10-29 11:18:18 -04:00
kernel/kallsyms.c: use __seq_open_private()
2014-10-14 02:18:16 +02:00
kcmp: fix standard comparison bug
2014-09-10 15:42:12 -07:00
locking/mcs: Better differentiate between MCS variants
2015-01-14 15:07:32 +01:00
kexec: simplify conditional
2015-02-17 14:34:51 -08:00
usermodehelper: kill the kmod_thread_locker logic
2014-12-10 17:41:17 -08:00
kprobes: makes kprobes/enabled works correctly for optimized kprobes.
2015-02-13 21:21:42 -08:00
kernel/kthread.c: partial revert of 81c98869fa ("kthread: ensure locality of task_struct allocations")
2014-10-09 22:25:51 -04:00
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
2015-02-11 20:25:11 -08:00
Copy the kernel module data from user space in chunks
2015-04-08 14:35:48 -07:00
rcu: Make SRCU optional by using CONFIG_SRCU
2015-01-06 11:04:29 -08:00
bury struct proc_ns in fs/proc
2014-12-04 14:34:54 -05:00
padata: use %*pb[l] to print bitmaps including cpumasks and nodemasks
2015-02-13 21:21:38 -08:00
livepatch: kernel: add TAINT_LIVEPATCH
2014-12-22 15:40:48 +01:00
param: fix uninitialized read with CONFIG_DEBUG_LOCK_ALLOC
2015-01-20 11:38:31 +10:30
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2014-12-16 15:53:03 -08:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2014-12-16 15:53:03 -08:00
profile: use %*pb[l] to print bitmaps including cpumasks and nodemasks
2015-02-13 21:21:38 -08:00
ptrace: remove linux/compat.h inclusion under CONFIG_COMPAT
2015-02-17 14:34:51 -08:00
kernel: avoid overflow in cmp_range
2015-01-17 10:02:23 +13:00
kernel: add support for kernel restart handler call chain
2014-09-26 00:00:06 -07:00
resources: Move struct resource_list_entry from ACPI into resource core
2015-02-05 15:09:25 +01:00
seccomp: cap SECCOMP_RET_ERRNO data to MAX_ERRNO
2015-02-17 14:34:55 -08:00
signal: use current->state helpers
2015-02-17 14:34:51 -08:00
smp: Fix smp_call_function_single_async() locking
2015-04-17 09:57:52 +02:00
smpboot: Add missing get_online_cpus() in smpboot_register_percpu_thread()
2015-01-23 11:33:51 +01:00
Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2015-02-09 15:24:03 -08:00
stacktrace: introduce snprint_stack_trace for buffer output
2014-12-13 12:42:48 -08:00
kernel/sys.c: fix UNAME26 for 4.0
2015-02-28 09:57:51 -08:00
syscalls: implement execveat() system call
2014-12-13 12:42:51 -08:00
fs: add dirtytime_expire_seconds sysctl
2015-03-17 12:23:32 -04:00
kernel: add panic_on_warn
2014-12-10 17:41:10 -08:00
netlink: make nlmsg_end() and genlmsg_end() void
2015-01-18 01:03:45 -05:00
kernel/test_kprobes.c: use current logging functions
2014-08-08 15:57:18 -07:00
torture: Address race in module cleanup
2014-09-16 13:41:06 -07:00
groups: Consolidate the setgroups permission checks
2014-12-05 17:19:27 -06:00
scheduler: Replace __get_cpu_var with this_cpu_ptr
2014-08-26 13:45:45 -04:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
2014-12-17 12:31:40 -08:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
2014-12-17 12:31:40 -08:00
copy address of proc_ns_ops into ns_common
2014-12-04 14:34:47 -05:00
kernel/sched/clock.c: add another clock for use with the soft lockup watchdog
2015-02-12 18:54:13 -08:00
workqueue: fix hang involving racing cancel[_delayed]_work_sync()'s for PREEMPT_NONE
2015-03-05 08:04:13 -05:00
8053871d0f