During a mkdir, the entire limbo list is synchronously checked on each
package for free RMIDs by sending IPIs. With a large number of RMIDs (SKL
has 192) this creates a intolerable amount of work in IPIs.

Replace the IPI based checking of the limbo list with asynchronous worker
threads on each package which periodically scan the limbo list and move the
RMIDs that have:

	llc_occupancy < threshold_occupancy

on all packages to the free list.

mkdir now returns -ENOSPC if the free list and the limbo list ere empty or
returns -EBUSY if there are RMIDs on the limbo list and the free list is
empty.

Getting rid of the IPIs also simplifies the data structures and the
serialization required for handling the lists.

[ tglx: Rewrote changelog ... ]
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Link: http://lkml.kernel.org/r/1502845243-20454-3-git-send-email-vikas.shivappa@linux.intel.com

When a CPU is dying, the overflow worker is canceled and rescheduled on a
different CPU in the same domain. But if the timer is already about to
expire this essentially doubles the interval which might result in a non
detected overflow.

Cancel the overflow worker and reschedule it immediately on a different CPU
in same domain. The work could be flushed as well, but that would
reschedule it on the same CPU.

[ tglx: Rewrote changelog once again ]
Reported-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Link: http://lkml.kernel.org/r/1502845243-20454-2-git-send-email-vikas.shivappa@linux.intel.com

Currently we have pqr_state and rdt_default_state which store the cached
CLOSID/RMIDs and the user configured cpu default values respectively. We
touch both of these during context switch. Put all of them in one
structure so that we can spare a cache line.
Reported-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: sai.praneeth.prakhya@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Link: http://lkml.kernel.org/r/1502304395-7166-3-git-send-email-vikas.shivappa@linux.intel.com

The user configured per cpu default RMID is not cleared during cpu
hotplug. This may lead to incorrect RMID values after a cpu goes offline
and again comes back online. Clear the per cpu default RMID during cpu
offline and online handling.
Reported-by: NPrakyha Sai Praneeth <sai.praneeth.prakhya@intel.com>
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Link: http://lkml.kernel.org/r/1502304395-7166-2-git-send-email-vikas.shivappa@linux.intel.com

CPUID.(EAX=0x10, ECX=res#):EBX[31:0] reports a bit mask for a resource.
Each set bit within the length of the CBM indicates the corresponding
unit of the resource allocation may be used by other entities in the
platform (e.g. an integrated graphics engine or hardware units outside
the processor core and have direct access to the resource). Each
cleared bit within the length of the CBM indicates the corresponding
allocation unit can be configured to implement a priority-based
allocation scheme without interference with other hardware agents in
the system. Bits outside the length of the CBM are reserved.

More details on the bit mask are described in x86 Software Developer's
Manual.

The bitmask is shown in "info" directory for each resource. It's
up to user to decide how to use the bitmask within a CBM in a partition
to share or isolate a resource with other executing units.
Suggested-by: NReinette Chatre <reinette.chatre@intel.com>
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: vikas.shivappa@linux.intel.com
Link: http://lkml.kernel.org/r/20170725223904.12996-1-tony.luck@intel.com

Set up a delayed work queue for each domain that will read all
the MBM counters of active RMIDs once per second to make sure
that they don't wrap around between reads from users.

[Tony: Added the initializations for the work structure and completed
the patch]
Signed-off-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-29-git-send-email-vikas.shivappa@linux.intel.com

MBM counters are monotonically increasing counts representing the total
memory bytes at a particular time. In order to calculate total_bytes for
an rdtgroup, we store the value of the counter when we create an
rdtgroup or when a new domain comes online.

When the total_bytes(all memory controller bytes) or local_bytes(local
memory controller bytes) file in "mon_data" is read it shows the
total bytes for that rdtgroup since its creation. User can snapshot this
at different time intervals to obtain bytes/second.
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-28-git-send-email-vikas.shivappa@linux.intel.com

Check CPUID bits for whether each of the MBM events is supported.
Allocate space for each RMID for each counter in each domain to save
previous MSR counter value and running total of data.
Create files in each of the monitor directories.
Signed-off-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-27-git-send-email-vikas.shivappa@linux.intel.com

Resource groups have a per domain directory under "mon_data". Add or
remove these directories as and when domains come online and go offline.
Also update the per cpu rmids and cache upon onlining and offlining
cpus.
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-26-git-send-email-vikas.shivappa@linux.intel.com

OS associates an RMID/CLOSid to a task by writing the per CPU
IA32_PQR_ASSOC MSR when a task is scheduled in.

The sched_in code will stay as no-op unless we are running on Intel SKU
which supports either resource control or monitoring and we also enable
them by mounting the resctrl fs.  The per cpu CLOSid/RMID values are
cached and the write is performed only when a task with a different
CLOSid/RMID is scheduled in.
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-25-git-send-email-vikas.shivappa@linux.intel.com

Introduce the usage of rdt_enable_key in sched_in code as a preparation
to add RDT monitoring support for sched_in.
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-24-git-send-email-vikas.shivappa@linux.intel.com

Add monitoring support during mount and unmount. Since root directory is
a "ctrl_mon" directory which can control and monitor resources create
the "mon_groups" directory which can hold monitor groups and a
"mon_data" directory which would hold all monitoring data like the rest
of resource groups.

The mount succeeds if either of monitoring or control/allocation is
enabled. If only monitoring is enabled user can still create monitor
groups under the "/sys/fs/resctrl/mon_groups/" and any mkdir under root
would fail. If only control/allocation is enabled all of the monitoring
related directories/files would not exist and resctrl would work in
legacy mode.
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-23-git-send-email-vikas.shivappa@linux.intel.com

Resource groups (ctrl_mon and monitor groups) are represented by
directories in resctrl fs. Add support to remove the directories.

When a ctrl_mon directory is removed all the cpus and tasks are assigned
back to the root rdtgroup. When a monitor group is removed the cpus and
tasks are returned to the parent control group.
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-22-git-send-email-vikas.shivappa@linux.intel.com

Re-factor the code to separate the ctrl group removal from the rmdir to
prepare to add RDT monitoring group removal.
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-21-git-send-email-vikas.shivappa@linux.intel.com

Add a mon_data directory for the root rdtgroup and all other rdtgroups.
The directory holds all of the monitored data for all domains and events
of all resources being monitored.

The mon_data itself has a list of directories in the format
mon_<domain_name>_<domain_id>. Each of these subdirectories contain one
file per event in the mode "0444". Reading the file displays a snapshot
of the monitored data for the event the file represents.

For ex, on a 2 socket Broadwell with llc_occupancy being
monitored the mon_data contents look as below:

$ ls /sys/fs/resctrl/p1/mon_data/
mon_L3_00
mon_L3_01

Each domain directory has one file per event:
$ ls /sys/fs/resctrl/p1/mon_data/mon_L3_00/
llc_occupancy

To read current llc_occupancy of ctrl_mon group p1
$ cat /sys/fs/resctrl/p1/mon_data/mon_L3_00/llc_occupancy
33789096

[This patch idea is based on Tony's sample patches to organise data in a
per domain directory and have one file per event (and use the fp->priv to
store mon data bits)]
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-20-git-send-email-vikas.shivappa@linux.intel.com

Rename the intel_rdt_schemata file to intel_rdt_ctrlmondata as we now
want to add support for RDT monitoring data for the events that are
supported in later patches.
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-19-git-send-email-vikas.shivappa@linux.intel.com

The cpus file is extended to support resource monitoring. This is used
to over-ride the RMID of the default group when running on specific
CPUs. It works similar to the resource control. The "cpus" and
"cpus_list" file is present in default group, ctrl_mon groups and
monitor groups.

Each "cpus" file or cpu_list file reads a cpumask or list showing which
CPUs belong to the resource group. By default all online cpus belong to
the default root group. A CPU can be present in one "ctrl_mon" and one
"monitor" group simultaneously. They can be added to a resource group by
writing the CPU to the file. When a CPU is added to a ctrl_mon group it
is automatically removed from the previous ctrl_mon group. A CPU can be
added to a monitor group only if it is present in the parent ctrl_mon
group and when a CPU is added to a monitor group, it is automatically
removed from the previous monitor group. When CPUs go offline, they are
automatically removed from the ctrl_mon and monitor groups.
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-18-git-send-email-vikas.shivappa@linux.intel.com

Separate the ctrl cpus file handling from the generic cpus file handling
and convert the per cpu closid from u32 to a struct which will be used
later to add rmid to the same struct. Also cleanup some name space.
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-17-git-send-email-vikas.shivappa@linux.intel.com

The root directory, ctrl_mon and monitor groups are populated
with a read/write file named "tasks". When read, it shows all the task
IDs assigned to the resource group.

Tasks can be added to groups by writing the PID to the file. A task can
be present in one "ctrl_mon" group "and" one "monitor" group. IOW a
PID_x can be seen in a ctrl_mon group and a monitor group at the same
time. When a task is added to a ctrl_mon group, it is automatically
removed from the previous ctrl_mon group where it belonged. Similarly if
a task is moved to a monitor group it is removed from the previous
monitor group . Also since the monitor groups can only have subset of
tasks of parent ctrl_mon group, a task can be moved to a monitor group
only if its already present in the parent ctrl_mon group.

Task membership is indicated by a new field in the task_struct "u32
rmid" which holds the RMID for the task. RMID=0 is reserved for the
default root group where the tasks belong to at mount.

[tony: zero the rmid if rdtgroup was deleted when task was being moved]
Signed-off-by: NTony Luck <tony.luck@linux.intel.com>
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-16-git-send-email-vikas.shivappa@linux.intel.com

OS associates a CLOSid(Class of service id) to a task by writing the
high 32 bits of per CPU IA32_PQR_ASSOC MSR when a task is scheduled in.
CPUID.(EAX=10H, ECX=1):EDX[15:0] enumerates the max CLOSID supported and
it is zero indexed. Hence change the type to u32 from int.
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-15-git-send-email-vikas.shivappa@linux.intel.com

Resource control groups can be created using mkdir in resctrl
fs(rdtgroup). In order to extend the resctrl interface to support
monitoring the control groups, extend the current mkdir to support
resource monitoring also.

This allows the rdtgroup created under the root directory to be able to
both control and monitor resources (ctrl_mon group). The ctrl_mon groups
are associated with one CLOSID like the legacy rdtgroups and one
RMID(Resource monitoring ID) as well. Hardware uses RMID to track the
resource usage. Once either of the CLOSID or RMID are exhausted, the
mkdir fails with -ENOSPC. If there are RMIDs in limbo list but not free
an -EBUSY is returned. User can also monitor a subset of the ctrl_mon
rdtgroup's tasks/cpus using the monitor groups. The monitor groups are
created using mkdir under the "mon_groups" directory in every ctrl_mon
group.

[Merged Tony's code: Removed a lot of common mkdir code, a fix to handling
of the list of the child rdtgroups and some cleanups in list
traversal. Also the changes to have similar alloc and free for CLOS/RMID
and return -EBUSY when RMIDs are in limbo and not free]
Signed-off-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-14-git-send-email-vikas.shivappa@linux.intel.com

Separate the ctrl mkdir code from the rest in order to prepare for
adding support for RDT monitoring mkdir support as well.
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-13-git-send-email-vikas.shivappa@linux.intel.com

Add info directory files specific to RDT monitoring.

 num_rmids:
    The number of RMIDs which are valid for the resource.

 mon_features:
    Lists the monitoring events if monitoring is enabled for the
    resource.

 max_threshold_occupancy:
    This is specific to llc_occupancy monitoring and is used to
    determine if an RMID can be reused. Provides an upper bound on the
    threshold and is shown to the user in bytes though the internal
    value will be rounded to the scaling factor supported by the h/w.
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-12-git-send-email-vikas.shivappa@linux.intel.com

The info directory files and base files need to be different for each
resource like cache and Memory bandwidth. With in each resource, the
files would be further different for monitoring and ctrl. This leads to
a lot of different static array declarations given that we are adding
resctrl monitoring.

Simplify this to one common list of files and then declare a set of
flags to choose the files based on the resource, whether it is info or
base and if it is control type file. This is as a preparation to include
monitoring based info and base files.

No functional change.

[Vikas: Extended the flags to have few bits per category like resource,
	info/base etc]
Signed-off-by: NTony luck <tony.luck@intel.com>
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-11-git-send-email-vikas.shivappa@linux.intel.com

Hardware uses RMID(Resource monitoring ID) to keep track of each of the
RDT events associated with tasks. The number of RMIDs is dependent on
the SKU and is enumerated via CPUID. We add support to manage the RMIDs
which include managing the RMID allocation and reading LLC occupancy
for an RMID.

RMID allocation is managed by keeping a free list which is initialized
to all available RMIDs except for RMID 0 which is always reserved for
root group. RMIDs goto a limbo list once they are
freed since the RMIDs are still tagged to cache lines of the tasks which
were using them - thereby still having some occupancy. They continue to
be in limbo list until the occupancy < threshold_occupancy. The
threshold_occupancy is a user configurable value.
OS uses IA32_QM_CTR MSR to read the occupancy associated with an RMID
after programming the IA32_EVENTSEL MSR with the RMID.

[Tony: Improved limbo search]
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-10-git-send-email-vikas.shivappa@linux.intel.com

Add common data structures for RDT resource monitoring and perform RDT
monitoring related data structure initializations which include setting
up the RMID(Resource monitoring ID) lists and event list which the
resource supports.

[ tony: some cleanup to make adding MBM easier later, remove "cqm" from
  	some names, make some data structure local to intel_rdt_monitor.c
  	static. Add copyright header]

[ tglx: Made it readable ]
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-9-git-send-email-vikas.shivappa@linux.intel.com

Change the format of the global rdt_resources_all. This holds all the
RDT resource structure initialization values. Make this more readable by
using the format:

rdt_resources_all[] = {
	[<resource_index>] =
            {...
	    }
	...
}
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-8-git-send-email-vikas.shivappa@linux.intel.com

Few of the data-structures have generic names although they are RDT
allocation specific. Rename them to be allocation specific to
accommodate RDT monitoring. E.g. s/enabled/alloc_enabled/

No functional change.
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-7-git-send-email-vikas.shivappa@linux.intel.com

Sparse reports that both of these can be static.

Make it so.
Signed-off-by: NReinette Chatre <reinette.chatre@intel.com>
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Link: http://lkml.kernel.org/r/1501017287-28083-6-git-send-email-vikas.shivappa@linux.intel.com

Because the "perf cqm" and resctrl code were separately added and
indivdually configurable, there seem to be separate context switch code
and also things on global .h which are not really needed.

Move only the scheduling specific code and definitions to
<asm/intel_rdt_sched.h> and the put all the other declarations to a
local intel_rdt.h.

h/t to Reinette Chatre for pointing out that we should separate the
public interfaces used by other parts of the kernel from private
objects shared between the various files comprising RDT.

No functional change.
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-5-git-send-email-vikas.shivappa@linux.intel.com

We currently have a CONFIG_RDT_A which is for RDT(Resource directory
technology) allocation based resctrl filesystem interface. As a
preparation to add support for RDT monitoring as well into the same
resctrl filesystem, change the config option to be CONFIG_RDT which
would include both RDT allocation and monitoring code.

No functional change.
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-4-git-send-email-vikas.shivappa@linux.intel.com

Add a description of resctrl based RDT(resource director technology)
monitoring extension and its usage.

[Tony: Added descriptions for how monitoring and allocation are measured
and some cleanups]
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-3-git-send-email-vikas.shivappa@linux.intel.com

'perf cqm' never worked due to the incompatibility between perf
infrastructure and cqm hardware support.  The hardware uses RMIDs to
track the llc occupancy of tasks and these RMIDs are per package. This
makes monitoring a hierarchy like cgroup along with monitoring of tasks
separately difficult and several patches sent to lkml to fix them were
NACKed. Further more, the following issues in the current perf cqm make
it almost unusable:

    1. No support to monitor the same group of tasks for which we do
    allocation using resctrl.

    2. It gives random and inaccurate data (mostly 0s) once we run out
    of RMIDs due to issues in Recycling.

    3. Recycling results in inaccuracy of data because we cannot
    guarantee that the RMID was stolen from a task when it was not
    pulling data into cache or even when it pulled the least data. Also
    for monitoring llc_occupancy, if we stop using an RMID_x and then
    start using an RMID_y after we reclaim an RMID from an other event,
    we miss accounting all the occupancy that was tagged to RMID_x at a
    later perf_count.

    2. Recycling code makes the monitoring code complex including
    scheduling because the event can lose RMID any time. Since MBM
    counters count bandwidth for a period of time by taking snap shot of
    total bytes at two different times, recycling complicates the way we
    count MBM in a hierarchy. Also we need a spin lock while we do the
    processing to account for MBM counter overflow. We also currently
    use a spin lock in scheduling to prevent the RMID from being taken
    away.

    4. Lack of support when we run different kind of event like task,
    system-wide and cgroup events together. Data mostly prints 0s. This
    is also because we can have only one RMID tied to a cpu as defined
    by the cqm hardware but a perf can at the same time tie multiple
    events during one sched_in.

    5. No support of monitoring a group of tasks. There is partial support
    for cgroup but it does not work once there is a hierarchy of cgroups
    or if we want to monitor a task in a cgroup and the cgroup itself.

    6. No support for monitoring tasks for the lifetime without perf
    overhead.

    7. It reported the aggregate cache occupancy or memory bandwidth over
    all sockets. But most cloud and VMM based use cases want to know the
    individual per-socket usage.
Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-2-git-send-email-vikas.shivappa@linux.intel.com

Pull x86 fixes from Thomas Gleixner:
 "A small set of x86 fixes:

   - prevent the kernel from using the EFI reboot method when EFI is
     disabled.

   - two patches addressing clang issues"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot: Disable the address-of-packed-member compiler warning
  x86/efi: Fix reboot_mode when EFI runtime services are disabled
  x86/boot: #undef memcpy() et al in string.c

Pull scheduler fixes from Thomas Gleixner:
 "Two patches addressing build warnings caused by inconsistent kernel
  doc comments"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/wait: Clean up some documentation warnings
  sched/core: Fix some documentation build warnings

Pull perf fixes from Thomas Gleixner:
 "A couple of fixes for performance counters and kprobes:

   - a series of small patches which make the uncore performance
     counters on Skylake server systems work correctly

   - add a missing instruction slot release to the failure path of
     kprobes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  kprobes/x86: Release insn_slot in failure path
  perf/x86/intel/uncore: Fix missing marker for skx_uncore_cha_extra_regs
  perf/x86/intel/uncore: Fix SKX CHA event extra regs
  perf/x86/intel/uncore: Remove invalid Skylake server CHA filter field
  perf/x86/intel/uncore: Fix Skylake server CHA LLC_LOOKUP event umask
  perf/x86/intel/uncore: Fix Skylake server PCU PMU event format
  perf/x86/intel/uncore: Fix Skylake UPI PMU event masks

Pull irq fix from Thomas Gleixner:
 "Fix for a regression caused by the conversion of x86 to the generic
  hotplug code.

  Instead of doing a plain single line revert, this adds a pile of
  comments so the semantics of the force argument are clear"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/cpuhotplug: Revert "Set force affinity flag on hotplug migration"

Pull DeviceTree fixes from Rob Herring:
 "Two small DT fixes:

   - Fix error handling in of_irq_to_resource_table() due to
     of_irq_to_resource() error return changes.

   - Fix dtx_diff script due to dts include path changes"

* tag 'devicetree-fixes-for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  of: irq: fix of_irq_to_resource() error check
  scripts/dtc: dtx_diff - update include dts paths to match build

Pull NFS client fixes from Anna Schumaker:
 "More NFS client bugfixes for 4.13.

  Most of these fix locking bugs that Ben and Neil noticed, but I also
  have a patch to fix one more access bug that was reported after last
  week.

  Stable fixes:
   - Fix a race where CB_NOTIFY_LOCK fails to wake a waiter
   - Invalidate file size when taking a lock to prevent corruption

  Other fixes:
   - Don't excessively generate tiny writes with fallocate
   - Use the raw NFS access mask in nfs4_opendata_access()"

* tag 'nfs-for-4.13-3' of git://git.linux-nfs.org/projects/anna/linux-nfs:
  NFSv4.1: Fix a race where CB_NOTIFY_LOCK fails to wake a waiter
  NFS: Optimize fallocate by refreshing mapping when needed.
  NFS: invalidate file size when taking a lock.
  NFS: Use raw NFS access mask in nfs4_opendata_access()