Tim Chen
3cf2f34e1a
rwsem: Add comments to explain the meaning of the rwsem's count field
...
It took me quite a while to understand how rwsem's count field
mainifested itself in different scenarios.
Add comments to provide a quick reference to the the rwsem's count
field for each scenario where readers and writers are contending
for the lock.
Hopefully it will be useful for future maintenance of the code and
for people to get up to speed on how the logic in the code works.
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Davidlohr Bueso <davidlohr@hp.com>
Cc: Alex Shi <alex.shi@linaro.org>
Cc: Michel Lespinasse <walken@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Paul E.McKenney <paulmck@linux.vnet.ibm.com>
Cc: Jason Low <jason.low2@hp.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1399060437.2970.146.camel@schen9-DESK
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-04 20:34:26 +02:00
..
debug
arch: Mass conversion of smp_mb__*()
2014-04-18 14:20:48 +02:00
events
Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
2014-04-05 13:20:43 -07:00
gcov
irq
genirq: Export symbol no_action()
2014-03-22 11:33:09 +01:00
locking
rwsem: Add comments to explain the meaning of the rwsem's count field
2014-05-04 20:34:26 +02:00
power
kernel: use macros from compiler.h instead of __attribute__((...))
2014-04-07 16:36:11 -07:00
printk
printk: fix one circular lockdep warning about console_lock
2014-04-03 16:21:08 -07:00
rcu
arch: Mass conversion of smp_mb__*()
2014-04-18 14:20:48 +02:00
sched
arch: Mass conversion of smp_mb__*()
2014-04-18 14:20:48 +02:00
time
kernel: use macros from compiler.h instead of __attribute__((...))
2014-04-07 16:36:11 -07:00
trace
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2014-04-12 14:49:50 -07:00
.gitignore
acct.c
async.c
audit.c
Merge git://git.infradead.org/users/eparis/audit
2014-04-12 12:38:53 -07:00
audit.h
audit: Use struct net not pid_t to remember the network namespce to reply in
2014-03-20 10:10:53 -04:00
audit_tree.c
inotify: Fix reporting of cookies for inotify events
2014-02-18 11:17:17 +01:00
audit_watch.c
inotify: Fix reporting of cookies for inotify events
2014-02-18 11:17:17 +01:00
auditfilter.c
Merge git://git.infradead.org/users/eparis/audit
2014-04-12 12:38:53 -07:00
auditsc.c
Merge git://git.infradead.org/users/eparis/audit
2014-04-12 12:38:53 -07:00
backtracetest.c
bounds.c
mm: do not allocate page->ptl dynamically, if spinlock_t fits to long
2013-12-20 12:25:45 -08:00
capability.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
2014-04-03 09:26:18 -07:00
cgroup.c
cgroup: newly created dirs and files should be owned by the creator
2014-04-07 16:44:47 -04:00
cgroup_freezer.c
cgroup: drop const from @buffer of cftype->write_string()
2014-03-19 10:23:54 -04:00
compat.c
Merge branch 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2014-04-02 12:51:41 -07:00
configs.c
context_tracking.c
cpu.c
CPU hotplug: Provide lockless versions of callback registration functions
2014-03-20 13:43:40 +01:00
cpu_pm.c
cpuset.c
Merge branch 'akpm' (incoming from Andrew)
2014-04-03 16:22:16 -07:00
crash_dump.c
cred.c
delayacct.c
dma.c
elfcore.c
exec_domain.c
exit.c
wait: WSTOPPED|WCONTINUED doesn't work if a zombie leader is traced by another process
2014-04-07 16:36:06 -07:00
extable.c
asmlinkage: Make main_extable_sort_needed visible
2014-02-13 18:13:22 -08:00
fork.c
kernel: use macros from compiler.h instead of __attribute__((...))
2014-04-07 16:36:11 -07:00
freezer.c
libata, freezer: avoid block device removal while system is frozen
2013-12-19 13:50:32 -05:00
futex.c
arch: Mass conversion of smp_mb__*()
2014-04-18 14:20:48 +02:00
futex_compat.c
compat: Get rid of (get|put)_compat_time(val|spec)
2014-02-02 14:09:12 -08:00
groups.c
kernel/groups.c: remove return value of set_groups
2014-04-03 16:21:05 -07:00
hrtimer.c
timer: Remove code redundancy while calling get_nohz_timer_target()
2014-03-20 12:35:46 +01:00
hung_task.c
kernel: audit/fix non-modular users of module_init in core code
2014-04-03 16:21:07 -07:00
irq_work.c
perf/x86: Warn to early_printk() in case irq_work is too slow
2014-02-21 21:49:07 +01:00
itimer.c
jump_label.c
kallsyms.c
kernel: use macros from compiler.h instead of __attribute__((...))
2014-04-07 16:36:11 -07:00
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kexec.c
kernel: use macros from compiler.h instead of __attribute__((...))
2014-04-07 16:36:11 -07:00
kmod.c
arch: Mass conversion of smp_mb__*()
2014-04-18 14:20:48 +02:00
kprobes.c
ksysfs.c
kernel: use macros from compiler.h instead of __attribute__((...))
2014-04-07 16:36:11 -07:00
kthread.c
kthread: ensure locality of task_struct allocations
2014-04-03 16:20:49 -07:00
latencytop.c
Makefile
Merge branch 'x86-asmlinkage-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2014-03-31 14:13:25 -07:00
module-internal.h
module.c
modules: use raw_cpu_write for initialization of per cpu refcount.
2014-04-07 16:36:14 -07:00
module_signing.c
notifier.c
notifier: Substitute rcu_access_pointer() for rcu_dereference_raw()
2014-02-26 06:35:13 -08:00
nsproxy.c
padata.c
panic.c
kernel/panic.c: display reason at end + pr_emerg
2014-04-07 16:36:08 -07:00
params.c
pid.c
pid_namespace.c
pid_namespace: pidns_get() should check task_active_pid_ns() != NULL
2014-04-02 16:20:21 -07:00
posix-cpu-timers.c
posix-timers.c
profile.c
CPU hotplug notifiers registration fixes for 3.15-rc1
2014-04-07 14:55:46 -07:00
ptrace.c
kernel/compat: convert to COMPAT_SYSCALL_DEFINE
2014-03-06 15:35:10 +01:00
range.c
reboot.c
relay.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2014-04-12 14:49:50 -07:00
res_counter.c
res_counter: remove interface for locked charging and uncharging
2014-04-07 16:35:54 -07:00
resource.c
kernel/resource.c: make reallocate_resource() static
2014-04-03 16:21:07 -07:00
seccomp.c
seccomp: fix populating a0-a5 syscall args in 32-bit x86 BPF
2014-04-14 16:26:47 -04:00
signal.c
kernel: use macros from compiler.h instead of __attribute__((...))
2014-04-07 16:36:11 -07:00
smp.c
smp: Rename __smp_call_function_single() to smp_call_function_single_async()
2014-02-24 14:47:15 -08:00
smpboot.c
smpboot.h
softirq.c
softirq: Add linux/irq.h to make it compile again
2014-03-19 11:28:14 +01:00
stacktrace.c
stop_machine.c
stop_machine: Fix^2 race between stop_two_cpus() and stop_cpus()
2014-03-11 11:33:47 +01:00
sys.c
mm, thp: add VM_INIT_DEF_MASK and PRCTL_THP_DISABLE
2014-04-07 16:35:52 -07:00
sys_ni.c
fs, kernel: permit disabling the uselib syscall
2014-04-03 16:21:05 -07:00
sysctl.c
hung_task: check the value of "sysctl_hung_task_timeout_sec"
2014-04-07 16:36:07 -07:00
sysctl_binary.c
system_certificates.S
system_keyring.c
task_work.c
taskstats.c
test_kprobes.c
time.c
timeconst.bc
timer.c
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2014-04-01 11:00:07 -07:00
torture.c
rcutorture: Gracefully handle NULL cleanup hooks
2014-02-23 09:04:39 -08:00
tracepoint.c
This includes the final patch to clean up and fix the issue with the
2014-04-12 13:06:10 -07:00
tsacct.c
uid16.c
up.c
smp: Rename __smp_call_function_single() to smp_call_function_single_async()
2014-02-24 14:47:15 -08:00
user-return-notifier.c
user.c
kernel: audit/fix non-modular users of module_init in core code
2014-04-03 16:21:07 -07:00
user_namespace.c
user namespace: fix incorrect memory barriers
2014-04-14 16:03:02 -07:00
utsname.c
utsname_sysctl.c
watchdog.c
kernel/watchdog.c: touch_nmi_watchdog should only touch local cpu not every one
2014-04-03 16:20:58 -07:00
workqueue.c
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2014-04-01 11:00:07 -07:00
workqueue_internal.h