linux-sg2042/arch/arm/kernel
Joonsoo Kim 7c4e9ced42 ARM: 7643/1: sched: correct update_sched_clock()
If we want load epoch_cyc and epoch_ns atomically,
we should update epoch_cyc_copy first of all.
This notify reader that updating is in progress.

If we update epoch_cyc first like as current implementation,
there is subtle error case.
Look at the below example.

<Initial Condition>
cyc = 9
ns = 900
cyc_copy = 9

== CASE 1 ==
<CPU A = reader>           <CPU B = updater>
                           write cyc = 10
read cyc = 10
read ns = 900
                           write ns = 1000
                           write cyc_copy = 10
read cyc_copy = 10

output = (10, 900)

== CASE 2 ==
<CPU A = reader>           <CPU B = updater>
read cyc = 9
                           write cyc = 10
                           write ns = 1000
read ns = 1000
read cyc_copy = 9
                           write cyc_copy = 10
output = (9, 1000)

If atomic read is ensured, output should be (9, 900) or (10, 1000).
But, output in example case are not.

So, change updating sequence in order to correct this problem.

Cc: <stable@vger.kernel.org>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-02-11 17:33:08 +00:00
..
.gitignore
Makefile Merge branch 'fixes' into for-linus 2012-10-11 10:55:04 +01:00
arch_timer.c ARM: 7538/1: delay: add registration mechanism for delay timer sources 2012-09-26 22:57:52 +01:00
armksyms.c Merge branches 'audit', 'delay', 'fixes', 'misc' and 'sta2x11' into for-linus 2012-07-27 23:06:32 +01:00
arthur.c
asm-offsets.c ARM: Don't unconditionally bloat thread_info 2012-08-29 11:18:17 +01:00
atags.h ARM: 7506/1: allow for ATAGS to be configured out when DT support is selected 2012-09-03 22:56:15 +01:00
atags_compat.c ARM: 7505/1: split out ATAGS parsing 2012-09-03 22:55:56 +01:00
atags_parse.c ARM: 7505/1: split out ATAGS parsing 2012-09-03 22:55:56 +01:00
atags_proc.c ARM: 7505/1: split out ATAGS parsing 2012-09-03 22:55:56 +01:00
bios32.c ARM: drivers: remove __dev* attributes. 2013-01-03 15:57:04 -08:00
calls.S Nothing all that exciting; a new module-from-fd syscall for those who want 2012-12-19 07:55:08 -08:00
cpuidle.c cpuidle: Add common time keeping and irq enabling 2012-03-21 01:59:40 -04:00
crash_dump.c crash_dump: export is_kdump_kernel to modules, consolidate elfcorehdr_addr, setup_elfcorehdr and saved_max_pfn 2011-03-23 19:47:19 -07:00
debug.S ARM: compile fix for DEBUG_LL=y && MMU=n 2013-01-16 14:30:06 -08:00
devtree.c ARM: 7585/1: kernel: fix nr_cpu_ids check in DT logical map init 2012-11-23 13:01:31 +00:00
dma-isa.c ARM: dma-isa: request cascade channel after registering it 2009-12-24 18:34:08 +00:00
dma.c locking, ARM: Annotate low level hw locks as raw 2011-09-13 11:12:14 +02:00
early_printk.c ARM: Add an earlyprintk debug console 2009-12-09 10:02:18 +00:00
elf.c Disintegrate asm/system.h for ARM 2012-03-28 18:30:01 +01:00
entry-armv.S ARM: Fix undefined instruction exception handling 2012-07-31 12:04:30 +01:00
entry-common.S Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2012-12-12 12:22:13 -08:00
entry-header.S Merge branch 'devel-stable' into for-next 2011-07-22 23:09:07 +01:00
etm.c ARM: drivers: remove __dev* attributes. 2013-01-03 15:57:04 -08:00
fiq.c ARM: fiq: change FIQ_START to a variable 2012-07-01 21:59:19 +08:00
fiqasm.S ARM: 6938/1: fiq: Refactor {get,set}_fiq_regs() for Thumb-2 2011-05-26 10:31:06 +01:00
ftrace.c ARM: 7468/1: ftrace: Trace function entry before updating index 2012-07-31 10:30:42 +01:00
head-common.S arm/dt: Make __vet_atags also accept a dtb image 2011-05-11 15:12:32 +02:00
head-nommu.S ARM: 7591/1: nommu: Enable the strict alignment (CR_A) bit only if ARCH < v6 2012-12-07 11:48:57 +00:00
head.S Merge branch 'for-rmk/virt/hyp-boot/fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into fixes 2013-01-19 15:27:30 +00:00
hw_breakpoint.c ARM: hw_breakpoint: kill WARN_ONCE usage 2012-11-09 11:47:06 +00:00
hyp-stub.S ARM: virt: simplify __hyp_stub_install epilog 2013-01-10 21:08:55 +00:00
insn.c ARM: fix missing bug.h include in arch/arm/kernel/insn.c 2012-03-30 11:51:46 +01:00
insn.h ARM: 7334/1: add jump label support 2012-03-24 09:38:56 +00:00
io.c arm: convert core files from module.h to export.h 2011-10-31 19:30:49 -04:00
irq.c ARM: export set_irq_flags 2012-10-09 20:24:24 +02:00
isa.c
iwmmxt.S ARM: pxa: fix logic error in PJ4 iWMMXt handling 2011-08-11 10:10:26 +08:00
jump_label.c ARM: 7334/1: add jump label support 2012-03-24 09:38:56 +00:00
kgdb.c kgdb,arm: fix register dump 2010-10-29 13:14:40 -05:00
kprobes-arm.c ARM: 7181/1: Restrict kprobes probing SWP instructions to ARMv5 and below 2011-11-30 23:54:54 +00:00
kprobes-common.c Disintegrate asm/system.h for ARM 2012-03-28 18:30:01 +01:00
kprobes-test-arm.c ARM: kprobes: make more tests conditional 2012-10-09 17:07:43 +02:00
kprobes-test-thumb.c ARM: 7174/1: Fix build error in kprobes test code on Thumb2 kernels 2011-11-26 21:58:53 +00:00
kprobes-test.c treewide: fix printk typo in multiple drivers 2012-11-19 11:08:17 +01:00
kprobes-test.h ARM: 7174/1: Fix build error in kprobes test code on Thumb2 kernels 2011-11-26 21:58:53 +00:00
kprobes-thumb.c ARM: 7423/1: kprobes: run t32_simulate_ldr_literal() without insn slot 2012-06-14 15:11:44 +01:00
kprobes.c Autogenerated GPG tag for Rusty D1ADB8F1: 15EE 8D6C AB0E 7F0C F999 BFCB D920 0E6C D1AD B8F1 2012-04-02 08:53:24 -07:00
kprobes.h ARM: kprobes: Add exports for test code 2011-09-20 18:17:43 +00:00
machine_kexec.c ARM: 7555/1: kexec: fix segment memory addresses check 2012-10-18 11:05:19 +01:00
module.c ARM: 7059/1: LPAE: Use PMD_(SHIFT|SIZE|MASK) instead of PGDIR_* 2011-08-23 15:30:33 +01:00
opcodes.c ARM: 7206/1: Add generic ARM instruction set condition code checks. 2011-12-13 08:52:02 +00:00
patch.c ARM: 7332/1: extract out code patch function from kprobes 2012-03-24 09:38:55 +00:00
patch.h ARM: 7332/1: extract out code patch function from kprobes 2012-03-24 09:38:55 +00:00
perf_event.c ARM: PMU: fix runtime PM enable 2012-11-09 11:37:26 +00:00
perf_event_cpu.c ARM: drivers: remove __dev* attributes. 2013-01-03 15:57:04 -08:00
perf_event_v6.c ARM: drivers: remove __dev* attributes. 2013-01-03 15:57:04 -08:00
perf_event_v7.c ARM: drivers: remove __dev* attributes. 2013-01-03 15:57:04 -08:00
perf_event_xscale.c ARM: drivers: remove __dev* attributes. 2013-01-03 15:57:04 -08:00
pj4-cp0.c arm: remove several unnecessary module.h include instances 2011-10-31 19:30:48 -04:00
process.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2012-12-12 12:22:13 -08:00
ptrace.c ARM: 7595/1: syscall: rework ordering in syscall_trace_exit 2012-12-11 00:18:26 +00:00
relocate_kernel.S ARM: 7065/1: kexec: ensure new kernel is entered in ARM state 2011-08-28 10:39:41 +01:00
return_address.c arm: convert core files from module.h to export.h 2011-10-31 19:30:49 -04:00
sched_clock.c ARM: 7643/1: sched: correct update_sched_clock() 2013-02-11 17:33:08 +00:00
setup.c ARM: 7602/1: Pass real "__machine_arch_type" variable to setup_machine_tags() procedure 2012-12-16 10:04:24 +00:00
signal.c Uninclude linux/freezer.h 2012-10-01 09:58:18 -04:00
signal.h ARM: 7471/1: Revert "7442/1: Revert "remove unused restart trampoline"" 2012-07-28 11:11:51 +01:00
sleep.S Disintegrate asm/system.h for ARM 2012-03-28 18:30:01 +01:00
smp.c Merge branch 'devel-stable' into for-linus 2012-12-11 10:01:53 +00:00
smp_scu.c ARM: 7347/1: SCU: use cpu_logical_map for per-CPU low power mode 2012-04-28 17:31:37 +01:00
smp_tlb.c smp: introduce a generic on_each_cpu_mask() function 2012-03-28 17:14:35 -07:00
smp_twd.c ARM: arm-soc: SoC updates for 3.8 2012-12-12 12:05:15 -08:00
stacktrace.c arm: convert core files from module.h to export.h 2011-10-31 19:30:49 -04:00
suspend.c ARM: kernel: update cpu_suspend code to use cache LoUIS operations 2012-09-25 11:20:26 +01:00
swp_emulate.c ARM: missing ->mmap_sem around find_vma() in swp_emulate.c 2012-12-20 10:40:24 +00:00
sys_arm.c arm: switch to generic fork/vfork/clone 2012-11-28 22:13:54 -05:00
sys_oabi-compat.c userns: Convert stat to return values mapped from kuids and kgids 2012-05-15 14:08:35 -07:00
tcm.c Disintegrate asm/system.h for ARM 2012-03-28 18:30:01 +01:00
tcm.h
thumbee.c ARM: 7385/1: ThumbEE: Use cpuid macros to read ID_PFR0 for ThumbEE 2012-04-25 19:49:26 +01:00
time.c ARM: use new LEDS CPU trigger stub to replace old one 2012-08-01 11:22:14 +08:00
topology.c ARM: kernel: update topology to use new MPIDR macros 2012-11-19 15:44:33 +00:00
traps.c ARM: 7526/1: traps: send SIGILL if get_user fails on undef handling path 2012-09-07 20:40:44 +01:00
unwind.c ARM: unwinder: fix bisection to find origin in .idx section 2011-12-15 14:02:19 -08:00
vmlinux.lds.S ARM: 7605/1: vmlinux.lds: Move .notes section next to the rodata 2012-12-16 10:04:24 +00:00
xscale-cp0.c arm: remove several unnecessary module.h include instances 2011-10-31 19:30:48 -04:00