diff options
author | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2013-05-15 10:26:50 -0400 |
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committer | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2013-05-15 10:26:50 -0400 |
commit | 12e04ffcd93b25dfd726d46338c2ee7d23de556e (patch) | |
tree | f91479a62805619168994fd3ee55e3ffa23fc24e /arch/arm/kernel/smp.c | |
parent | 9eff37a8713939f218ab8bf0dc93f1d67af7b8b4 (diff) | |
parent | f722406faae2d073cc1d01063d1123c35425939e (diff) |
Merge tag 'v3.10-rc1' into stable/for-linus-3.10
Linux 3.10-rc1
* tag 'v3.10-rc1': (12273 commits)
Linux 3.10-rc1
[SCSI] qla2xxx: Update firmware link in Kconfig file.
[SCSI] iscsi class, qla4xxx: fix sess/conn refcounting when find fns are used
[SCSI] sas: unify the pointlessly separated enums sas_dev_type and sas_device_type
[SCSI] pm80xx: thermal, sas controller config and error handling update
[SCSI] pm80xx: NCQ error handling changes
[SCSI] pm80xx: WWN Modification for PM8081/88/89 controllers
[SCSI] pm80xx: Changed module name and debug messages update
[SCSI] pm80xx: Firmware flash memory free fix, with addition of new memory region for it
[SCSI] pm80xx: SPC new firmware changes for device id 0x8081 alone
[SCSI] pm80xx: Added SPCv/ve specific hardware functionalities and relevant changes in common files
[SCSI] pm80xx: MSI-X implementation for using 64 interrupts
[SCSI] pm80xx: Updated common functions common for SPC and SPCv/ve
[SCSI] pm80xx: Multiple inbound/outbound queue configuration
[SCSI] pm80xx: Added SPCv/ve specific ids, variables and modify for SPC
[SCSI] lpfc: fix up Kconfig dependencies
[SCSI] Handle MLQUEUE busy response in scsi_send_eh_cmnd
dm cache: set config value
dm cache: move config fns
dm thin: generate event when metadata threshold passed
...
Diffstat (limited to 'arch/arm/kernel/smp.c')
-rw-r--r-- | arch/arm/kernel/smp.c | 44 |
1 files changed, 39 insertions, 5 deletions
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 1f2ccccaf00..47ab90563bf 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -211,6 +211,13 @@ void __cpuinit __cpu_die(unsigned int cpu) } printk(KERN_NOTICE "CPU%u: shutdown\n", cpu); + /* + * platform_cpu_kill() is generally expected to do the powering off + * and/or cutting of clocks to the dying CPU. Optionally, this may + * be done by the CPU which is dying in preference to supporting + * this call, but that means there is _no_ synchronisation between + * the requesting CPU and the dying CPU actually losing power. + */ if (!platform_cpu_kill(cpu)) printk("CPU%u: unable to kill\n", cpu); } @@ -230,14 +237,41 @@ void __ref cpu_die(void) idle_task_exit(); local_irq_disable(); - mb(); - /* Tell __cpu_die() that this CPU is now safe to dispose of */ + /* + * Flush the data out of the L1 cache for this CPU. This must be + * before the completion to ensure that data is safely written out + * before platform_cpu_kill() gets called - which may disable + * *this* CPU and power down its cache. + */ + flush_cache_louis(); + + /* + * Tell __cpu_die() that this CPU is now safe to dispose of. Once + * this returns, power and/or clocks can be removed at any point + * from this CPU and its cache by platform_cpu_kill(). + */ RCU_NONIDLE(complete(&cpu_died)); /* - * actual CPU shutdown procedure is at least platform (if not - * CPU) specific. + * Ensure that the cache lines associated with that completion are + * written out. This covers the case where _this_ CPU is doing the + * powering down, to ensure that the completion is visible to the + * CPU waiting for this one. + */ + flush_cache_louis(); + + /* + * The actual CPU shutdown procedure is at least platform (if not + * CPU) specific. This may remove power, or it may simply spin. + * + * Platforms are generally expected *NOT* to return from this call, + * although there are some which do because they have no way to + * power down the CPU. These platforms are the _only_ reason we + * have a return path which uses the fragment of assembly below. + * + * The return path should not be used for platforms which can + * power off the CPU. */ if (smp_ops.cpu_die) smp_ops.cpu_die(cpu); @@ -336,7 +370,7 @@ asmlinkage void __cpuinit secondary_start_kernel(void) /* * OK, it's off to the idle thread for us */ - cpu_idle(); + cpu_startup_entry(CPUHP_ONLINE); } void __init smp_cpus_done(unsigned int max_cpus) |