Peter Zijlstra (Intel)
c1fb159db9
locking/qspinlock: Add pending bit ...
Because the qspinlock needs to touch a second cacheline (the per-cpu
mcs_nodes[]); add a pending bit and allow a single in-word spinner
before we punt to the second cacheline.
It is possible so observe the pending bit without the locked bit when
the last owner has just released but the pending owner has not yet
taken ownership.
In this case we would normally queue -- because the pending bit is
already taken. However, in this case the pending bit is guaranteed
to be released 'soon', therefore wait for it and avoid queueing.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel J Blueman <daniel@numascale.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <paolo.bonzini@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1429901803-29771-4-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 12:36:32 +02:00
bpf: fix 64-bit divide
2015-04-27 23:11:49 -04:00
debug: prevent entering debug mode on panic/exception.
2015-02-19 12:39:03 -06:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
2015-04-15 09:00:47 -07:00
gcov: fix softlockups
2015-04-17 09:04:08 -04:00
irqchip core change for v4.1 (round 3)
2015-04-11 11:17:28 +02:00
Merge branch 'for-4.1/core-noarch' into for-linus
2015-04-13 23:57:20 +02:00
locking/qspinlock: Add pending bit
2015-05-08 12:36:32 +02:00
Merge back earlier suspend/hibernate material for v4.1.
2015-04-10 12:01:59 +02:00
TTY/Serial patches for 4.1-rc1
2015-04-21 09:33:10 -07:00
rcu: Control grace-period delays directly from value
2015-04-14 19:33:59 -07:00
Power management and ACPI fixes for v4.1-rc2
2015-04-30 14:23:31 -07:00
Char/Misc driver patches for 4.1-rc1
2015-04-21 09:42:58 -07:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2015-04-26 17:22:07 -07:00
acct: check FMODE_CAN_WRITE
2015-04-11 22:27:55 -04:00
kernel/async.c: switch to pr_foo()
2014-10-09 22:26:04 -04:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2015-04-26 17:22:07 -07:00
Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit
2015-04-22 14:49:23 -07:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2015-04-26 17:22:07 -07:00
VFS: audit: d_backing_inode() annotations
2015-04-15 15:06:55 -04:00
Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit
2015-02-11 20:07:47 -08:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2015-04-26 17:22:07 -07:00
kernel: conditionally support non-root users, groups and capabilities
2015-04-15 16:35:22 -07:00
cgroup: remove use of seq_printf return value
2015-04-15 16:35:25 -07:00
all arches, signal: move restart_block to struct task_struct
2015-02-12 18:54:12 -08:00
context_tracking: Export context_tracking_user_enter/exit
2015-03-09 15:43:00 +01:00
Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2015-04-14 13:36:04 -07:00
kernel, cpuset: remove exception for __GFP_THISNODE
2015-04-14 16:49:03 -07:00
kernel: conditionally support non-root users, groups and capabilities
2015-04-15 16:35:22 -07:00
Remove rest of exec domains.
2015-04-12 21:03:31 +02:00
Remove execution domain support
2015-04-12 20:58:24 +02:00
ftrace/x86/extable: Add is_ftrace_trampoline() function
2014-11-19 15:25:26 -05:00
oprofile: reduce mmap_sem hold for mm->exe_file
2015-04-17 09:04:11 -04:00
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
kernel: conditionally support non-root users, groups and capabilities
2015-04-15 16:35:22 -07:00
kernel/hung_task.c: change hung_task.c to use for_each_process_thread()
2015-04-15 16:35:22 -07:00
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
locking/qspinlock: Introduce a simple generic 4-byte queued spinlock
2015-05-08 12:36:25 +02:00
kexec: allocate the kexec control page with KEXEC_CONTROL_MEMORY_GFP
2015-04-23 16:52:01 +02:00
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
modsign: change default key details
2015-04-30 09:35:41 -07:00
Quentin opened a can of worms by adding extable entry checking to modpost,
2015-04-22 09:49:24 -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
params: handle quotes properly for values not of form foo="bar".
2015-04-15 13:31:23 +09:30
fork: report pid reservation failure properly
2015-04-17 09:04:06 -04:00
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: ptrace_detach() can no longer race with SIGKILL
2015-04-17 09:04:06 -04:00
kernel: avoid overflow in cmp_range
2015-01-17 10:02:23 +13:00
kernel/reboot.c: add orderly_reboot for graceful reboot
2015-04-15 16:35:23 -07:00
VFS: kernel/: d_inode() annotations
2015-04-15 15:06:55 -04:00
kernel/resource.c: remove deprecated __check_region() and friends
2015-04-15 16:35:22 -07:00
seccomp: cap SECCOMP_RET_ERRNO data to MAX_ERRNO
2015-02-17 14:34:55 -08:00
signal: remove warning about using SI_TKILL in rt_[tg]sigqueueinfo
2015-04-17 09:04:06 -04:00
smp: Fix error case handling in smp_call_function_*()
2015-04-19 13:19:23 -07:00
smpboot: Add common code for notification from dying CPU
2015-03-11 13:20:25 -07:00
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
prctl: avoid using mmap_sem for exe_file serialization
2015-04-17 09:04:07 -04:00
kernel: conditionally support non-root users, groups and capabilities
2015-04-15 16:35:22 -07:00
kernel/sysctl.c: detect overflows when converting to int
2015-04-17 09:04:08 -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
groups: Consolidate the setgroups permission checks
2014-12-05 17:19:27 -06:00
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
Merge branch 'akpm' (patches from Andrew)
2015-04-14 16:49:17 -07:00
workqueue: Reorder sysfs code
2015-04-06 11:16:04 -04:00
c1fb159db9