linux/drivers/powercap, branch v3.15-rc1

Merge tag 'cpu-hotplug-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2014-04-07T21:55:46Z

Pull CPU hotplug notifiers registration fixes from Rafael Wysocki: "The purpose of this single series of commits from Srivatsa S Bhat (with a small piece from Gautham R Shenoy) touching multiple subsystems that use CPU hotplug notifiers is to provide a way to register them that will not lead to deadlocks with CPU online/offline operations as described in the changelog of commit 93ae4f978ca7f ("CPU hotplug: Provide lockless versions of callback registration functions"). The first three commits in the series introduce the API and document it and the rest simply goes through the users of CPU hotplug notifiers and converts them to using the new method" * tag 'cpu-hotplug-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (52 commits) net/iucv/iucv.c: Fix CPU hotplug callback registration net/core/flow.c: Fix CPU hotplug callback registration mm, zswap: Fix CPU hotplug callback registration mm, vmstat: Fix CPU hotplug callback registration profile: Fix CPU hotplug callback registration trace, ring-buffer: Fix CPU hotplug callback registration xen, balloon: Fix CPU hotplug callback registration hwmon, via-cputemp: Fix CPU hotplug callback registration hwmon, coretemp: Fix CPU hotplug callback registration thermal, x86-pkg-temp: Fix CPU hotplug callback registration octeon, watchdog: Fix CPU hotplug callback registration oprofile, nmi-timer: Fix CPU hotplug callback registration intel-idle: Fix CPU hotplug callback registration clocksource, dummy-timer: Fix CPU hotplug callback registration drivers/base/topology.c: Fix CPU hotplug callback registration acpi-cpufreq: Fix CPU hotplug callback registration zsmalloc: Fix CPU hotplug callback registration scsi, fcoe: Fix CPU hotplug callback registration scsi, bnx2fc: Fix CPU hotplug callback registration scsi, bnx2i: Fix CPU hotplug callback registration ...

powercap, intel-rapl: Fix CPU hotplug callback registration

2014-03-20T12:43:44Z

Subsystems that want to register CPU hotplug callbacks, as well as perform initialization for the CPUs that are already online, often do it as shown below: get_online_cpus(); for_each_online_cpu(cpu) init_cpu(cpu); register_cpu_notifier(&foobar_cpu_notifier); put_online_cpus(); This is wrong, since it is prone to ABBA deadlocks involving the cpu_add_remove_lock and the cpu_hotplug.lock (when running concurrently with CPU hotplug operations). Instead, the correct and race-free way of performing the callback registration is: cpu_notifier_register_begin(); for_each_online_cpu(cpu) init_cpu(cpu); /* Note the use of the double underscored version of the API */ __register_cpu_notifier(&foobar_cpu_notifier); cpu_notifier_register_done(); Fix the intel-rapl code in the powercap driver by using this latter form of callback registration. But retain the calls to get/put_online_cpus(), since they also protect the function rapl_cleanup_data(). By nesting get/put_online_cpus() *inside* cpu_notifier_register_begin/done(), we avoid the ABBA deadlock possibility mentioned above. Cc: Srinivas Pandruvada Cc: Ingo Molnar Tested-by: Jacob Pan Signed-off-by: Srivatsa S. Bhat Signed-off-by: Rafael J. Wysocki

powercap / intel_rapl: spell out SoC names

2014-02-13T23:49:34Z

Spell out names for supported SoCs. Signed-off-by: Jacob Pan Signed-off-by: Rafael J. Wysocki

powercap / intel_rapl: relax sanity check on energy counters

2014-02-13T23:49:33Z

Some RAPL domains may not be active at the time driver is being loaded. Checking energy counter increment may be too strict and time consuming. So relax the sanity check on energy counters of these domains. Otherwise, they may be ignored and become unavailable to the powercap framework. Signed-off-by: Jacob Pan Signed-off-by: Rafael J. Wysocki

powercap / RAPL: add support for ValleyView Soc

2013-12-22T00:27:51Z

This patch adds support for RAPL on Intel ValleyView based SoC platforms, such as Baytrail. Besides adding CPU ID, special energy unit encoding is handled for ValleyView. Signed-off-by: Jacob Pan Signed-off-by: Rafael J. Wysocki

PowerCap: Fix mode for energy counter

2013-12-05T01:05:48Z

As per the documentation of powercap sysfs, energy_uj field is read only, if it can't be reset. Currently it always allows write but will fail, if there is no reset callback. Changing mode field, to read only if there is no reset callback. Signed-off-by: Srinivas Pandruvada Reported-by: Dirk Brandewie Signed-off-by: Rafael J. Wysocki

PowerCap: Fix build error with option -Werror=format-security

2013-11-05T01:36:57Z

Fix compile error with gcc option: -Werror=format-security for dev_set_name(&control_type->dev, name). Changed to dev_set_name(&control_type->dev, "%s", name). Signed-off-by: Srinivas Pandruvada Acked-by: Kees Cook Signed-off-by: Rafael J. Wysocki

PowerCap: Convert class code to use dev_groups

2013-10-25T21:16:31Z

The newly added power capping framework uses the obsolete .dev_attrs field of struct class. However this field will be removed in 3.13, so convert the code to use the .dev_groups field instead. Signed-off-by: Thierry Reding Acked-by: Greg Kroah-Hartman Signed-off-by: Rafael J. Wysocki

PowerCap: Introduce Intel RAPL power capping driver

2013-10-18T11:29:52Z

The Intel Running Average Power Limit (RAPL) technology provides platform software with the ability to monitor, control, and get notifications on power usage. This feature is present in all Sandy Bridge and later Intel processors. Newer models allow more fine grained controls to be applied. In RAPL, power control is divided into domains, which include package, DRAM controller, CPU core (Power Plane 0), graphics uncore (power plane 1), etc. The purpose of this driver is to expose the RAPL settings to userspace. Overall, RAPL fits in the new powercap class driver in that platform level power capping controls are exposed via this generic interface. This driver is based on an earlier patch from Zhang Rui. However, while the previous work was mainly focused on thermal monitoring the focus here is on the usability from user space perspective. References: https://lkml.org/lkml/2011/5/26/93 Signed-off-by: Srinivas Pandruvada Signed-off-by: Jacob Pan Reviewed-by: Rafael J. Wysocki Signed-off-by: Rafael J. Wysocki

PowerCap: Add class driver

2013-10-16T22:36:06Z

The power capping framework providing a consistent interface between the kernel and user space that allows power capping drivers to expose their settings to user space in a uniform way. The overall design of the framework is described in the documentation added by the previous patch in this series. Signed-off-by: Srinivas Pandruvada Signed-off-by: Jacob Pan Reviewed-by: Rafael J. Wysocki Signed-off-by: Rafael J. Wysocki