26 Commits

Author SHA1 Message Date
Linus Torvalds
42f6e869a0 - A first round of changes towards splitting the arch-specific bits from
the filesystem bits of resctrl, the ultimate goal being to support ARM's
 equivalent technology MPAM, with the same fs interface (James Morse)
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Merge tag 'x86_cache_for_v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 resource control updates from Borislav Petkov:
 "A first round of changes towards splitting the arch-specific bits from
  the filesystem bits of resctrl, the ultimate goal being to support
  ARM's equivalent technology MPAM, with the same fs interface (James
  Morse)"

* tag 'x86_cache_for_v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
  x86/resctrl: Make resctrl_arch_get_config() return its value
  x86/resctrl: Merge the CDP resources
  x86/resctrl: Expand resctrl_arch_update_domains()'s msr_param range
  x86/resctrl: Remove rdt_cdp_peer_get()
  x86/resctrl: Merge the ctrl_val arrays
  x86/resctrl: Calculate the index from the configuration type
  x86/resctrl: Apply offset correction when config is staged
  x86/resctrl: Make ctrlval arrays the same size
  x86/resctrl: Pass configuration type to resctrl_arch_get_config()
  x86/resctrl: Add a helper to read a closid's configuration
  x86/resctrl: Rename update_domains() to resctrl_arch_update_domains()
  x86/resctrl: Allow different CODE/DATA configurations to be staged
  x86/resctrl: Group staged configuration into a separate struct
  x86/resctrl: Move the schemata names into struct resctrl_schema
  x86/resctrl: Add a helper to read/set the CDP configuration
  x86/resctrl: Swizzle rdt_resource and resctrl_schema in pseudo_lock_region
  x86/resctrl: Pass the schema to resctrl filesystem functions
  x86/resctrl: Add resctrl_arch_get_num_closid()
  x86/resctrl: Store the effective num_closid in the schema
  x86/resctrl: Walk the resctrl schema list instead of an arch list
  ...
2021-08-30 13:31:36 -07:00
Babu Moger
527f721478 x86/resctrl: Fix a maybe-uninitialized build warning treated as error
The recent commit

  064855a69003 ("x86/resctrl: Fix default monitoring groups reporting")

caused a RHEL build failure with an uninitialized variable warning
treated as an error because it removed the default case snippet.

The RHEL Makefile uses '-Werror=maybe-uninitialized' to force possibly
uninitialized variable warnings to be treated as errors. This is also
reported by smatch via the 0day robot.

The error from the RHEL build is:

  arch/x86/kernel/cpu/resctrl/monitor.c: In function ‘__mon_event_count’:
  arch/x86/kernel/cpu/resctrl/monitor.c:261:12: error: ‘m’ may be used
  uninitialized in this function [-Werror=maybe-uninitialized]
    m->chunks += chunks;
              ^~

The upstream Makefile does not build using '-Werror=maybe-uninitialized'.
So, the problem is not seen there. Fix the problem by putting back the
default case snippet.

 [ bp: note that there's nothing wrong with the code and other compilers
   do not trigger this warning - this is being done just so the RHEL compiler
   is happy. ]

Fixes: 064855a69003 ("x86/resctrl: Fix default monitoring groups reporting")
Reported-by: Terry Bowman <Terry.Bowman@amd.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/162949631908.23903.17090272726012848523.stgit@bmoger-ubuntu
2021-08-22 09:11:29 +02:00
Babu Moger
064855a690 x86/resctrl: Fix default monitoring groups reporting
Creating a new sub monitoring group in the root /sys/fs/resctrl leads to
getting the "Unavailable" value for mbm_total_bytes and mbm_local_bytes
on the entire filesystem.

Steps to reproduce:

  1. mount -t resctrl resctrl /sys/fs/resctrl/

  2. cd /sys/fs/resctrl/

  3. cat mon_data/mon_L3_00/mbm_total_bytes
     23189832

  4. Create sub monitor group:
  mkdir mon_groups/test1

  5. cat mon_data/mon_L3_00/mbm_total_bytes
     Unavailable

When a new monitoring group is created, a new RMID is assigned to the
new group. But the RMID is not active yet. When the events are read on
the new RMID, it is expected to report the status as "Unavailable".

When the user reads the events on the default monitoring group with
multiple subgroups, the events on all subgroups are consolidated
together. Currently, if any of the RMID reads report as "Unavailable",
then everything will be reported as "Unavailable".

Fix the issue by discarding the "Unavailable" reads and reporting all
the successful RMID reads. This is not a problem on Intel systems as
Intel reports 0 on Inactive RMIDs.

Fixes: d89b7379015f ("x86/intel_rdt/cqm: Add mon_data")
Reported-by: Paweł Szulik <pawel.szulik@intel.com>
Signed-off-by: Babu Moger <Babu.Moger@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Reinette Chatre <reinette.chatre@intel.com>
Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=213311
Link: https://lkml.kernel.org/r/162793309296.9224.15871659871696482080.stgit@bmoger-ubuntu
2021-08-12 20:12:20 +02:00
James Morse
111136e69c x86/resctrl: Make resctrl_arch_get_config() return its value
resctrl_arch_get_config() has no return, but does pass a single value
back via one of its arguments.

Return the value instead.

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210811163831.14917-1-james.morse@arm.com
2021-08-11 18:42:53 +02:00
James Morse
fa8f711d2f x86/resctrl: Pass configuration type to resctrl_arch_get_config()
The ctrl_val[] array for a struct rdt_hw_resource only holds
configurations of one type. The type is implicit.

Once the CDP resources are merged, the ctrl_val[] array will hold all
the configurations for the hardware resource. When a particular type of
configuration is needed, it must be specified explicitly.

Pass the expected type from the schema into resctrl_arch_get_config().
Nothing uses this yet, but once a single ctrl_val[] array is used for
the three struct rdt_hw_resources that share hardware, the type will be
used to return the correct configuration value from the shared array.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jamie Iles <jamie@nuviainc.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lkml.kernel.org/r/20210728170637.25610-18-james.morse@arm.com
2021-08-11 17:53:53 +02:00
James Morse
f07e9d0250 x86/resctrl: Add a helper to read a closid's configuration
Functions like show_doms() reach into the architecture's private
structure to retrieve the configuration from the struct rdt_hw_resource.

The hardware configuration may look completely different to the
values resctrl gets from user-space. The staged configuration and
resctrl_arch_update_domains() allow the architecture to convert or
translate these values.

Resctrl shouldn't read or write the ctrl_val[] values directly. Add
a helper to read the current configuration. This will allow another
architecture to scale the bitmaps if necessary, and possibly use
controls that don't take the user-space control format at all.

Of the remaining functions that access ctrl_val[] directly,
apply_config() is part of the architecture-specific code, and is
called via resctrl_arch_update_domains(). reset_all_ctrls() will be an
architecture specific helper.

update_mba_bw() manipulates both ctrl_val[], mbps_val[] and the
hardware. The mbps_val[] that matches the mba_sc state of the resource
is changed, but the other is left unchanged. Abstracting this is the
subject of later patches that affect set_mba_sc() too.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jamie Iles <jamie@nuviainc.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lkml.kernel.org/r/20210728170637.25610-17-james.morse@arm.com
2021-08-11 17:46:34 +02:00
James Morse
792e0f6f78 x86/resctrl: Split struct rdt_domain
resctrl is the defacto Linux ABI for SoC resource partitioning features.

To support it on another architecture, it needs to be abstracted from
the features provided by Intel RDT and AMD PQoS, and moved to /fs/.
struct rdt_domain contains a mix of architecture private details and
properties of the filesystem interface user-space uses.

Continue by splitting struct rdt_domain, into an architecture private
'hw' struct, which contains the common resctrl structure that would be
used by any architecture. The hardware values in ctrl_val and mbps_val
need to be accessed via helpers to allow another architecture to convert
these into a different format if necessary. After this split, filesystem
code paths touching a 'hw' struct indicates where an abstraction is
needed.

Splitting this structure only moves types around, and should not lead
to any change in behaviour.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jamie Iles <jamie@nuviainc.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lkml.kernel.org/r/20210728170637.25610-3-james.morse@arm.com
2021-08-11 12:00:43 +02:00
James Morse
63c8b12319 x86/resctrl: Split struct rdt_resource
resctrl is the defacto Linux ABI for SoC resource partitioning features.

To support it on another architecture, it needs to be abstracted from
the features provided by Intel RDT and AMD PQoS, and moved to /fs/.
struct rdt_resource contains a mix of architecture private details
and properties of the filesystem interface user-space uses.

Start by splitting struct rdt_resource, into an architecture private
'hw' struct, which contains the common resctrl structure that would be
used by any architecture. The foreach helpers are most commonly used by
the filesystem code, and should return the common resctrl structure.
for_each_rdt_resource() is changed to walk the common structure in its
parent arch private structure.

Move as much of the structure as possible into the common structure
in the core code's header file. The x86 hardware accessors remain
part of the architecture private code, as do num_closid, mon_scale
and mbm_width.

mon_scale and mbm_width are used to detect overflow of the hardware
counters, and convert them from their native size to bytes. Any
cross-architecture abstraction should be in terms of bytes, making
these properties private.

The hardware's num_closid is kept in the private structure to force the
filesystem code to use a helper to access it. MPAM would return a single
value for the system, regardless of the resource. Using the helper
prevents this field from being confused with the version of num_closid
that is being exposed to user-space (added in a later patch).

After this split, filesystem code touching a 'hw' struct indicates
where an abstraction is needed.

Splitting this structure only moves types around, and should not lead
to any change in behaviour.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jamie Iles <jamie@nuviainc.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lkml.kernel.org/r/20210728170637.25610-2-james.morse@arm.com
2021-08-11 11:51:34 +02:00
Andi Kleen
4029b9706d x86/resctrl: Fix init const confusion
const variable must be initconst, not initdata.

Signed-off-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210425211229.3157674-1-ak@linux.intel.com
2021-05-05 21:50:14 +02:00
Ingo Molnar
163b099146 x86: Fix various typos in comments, take #2
Fix another ~42 single-word typos in arch/x86/ code comments,
missed a few in the first pass, in particular in .S files.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-kernel@vger.kernel.org
2021-03-21 23:50:28 +01:00
Ingo Molnar
d9f6e12fb0 x86: Fix various typos in comments
Fix ~144 single-word typos in arch/x86/ code comments.

Doing this in a single commit should reduce the churn.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-kernel@vger.kernel.org
2021-03-18 15:31:53 +01:00
Linus Torvalds
8ba27ae36b - Add logic to correct MBM total and local values fixing errata SKX99 and BDF102
(Fenghua Yu)
 
 - Cleanups.
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Merge tag 'x86_cache_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 cache resource control updates from Borislav Petkov:

 - add logic to correct MBM total and local values fixing errata SKX99
   and BDF102 (Fenghua Yu)

 - cleanups

* tag 'x86_cache_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/resctrl: Clean up unused function parameter in rmdir path
  x86/resctrl: Constify kernfs_ops
  x86/resctrl: Correct MBM total and local values
  Documentation/x86: Rename resctrl_ui.rst and add two errata to the file
2020-12-14 13:53:17 -08:00
Xiaochen Shen
06c5fe9b12 x86/resctrl: Fix incorrect local bandwidth when mba_sc is enabled
The MBA software controller (mba_sc) is a feedback loop which
periodically reads MBM counters and tries to restrict the bandwidth
below a user-specified value. It tags along the MBM counter overflow
handler to do the updates with 1s interval in mbm_update() and
update_mba_bw().

The purpose of mbm_update() is to periodically read the MBM counters to
make sure that the hardware counter doesn't wrap around more than once
between user samplings. mbm_update() calls __mon_event_count() for local
bandwidth updating when mba_sc is not enabled, but calls mbm_bw_count()
instead when mba_sc is enabled. __mon_event_count() will not be called
for local bandwidth updating in MBM counter overflow handler, but it is
still called when reading MBM local bandwidth counter file
'mbm_local_bytes', the call path is as below:

  rdtgroup_mondata_show()
    mon_event_read()
      mon_event_count()
        __mon_event_count()

In __mon_event_count(), m->chunks is updated by delta chunks which is
calculated from previous MSR value (m->prev_msr) and current MSR value.
When mba_sc is enabled, m->chunks is also updated in mbm_update() by
mistake by the delta chunks which is calculated from m->prev_bw_msr
instead of m->prev_msr. But m->chunks is not used in update_mba_bw() in
the mba_sc feedback loop.

When reading MBM local bandwidth counter file, m->chunks was changed
unexpectedly by mbm_bw_count(). As a result, the incorrect local
bandwidth counter which calculated from incorrect m->chunks is shown to
the user.

Fix this by removing incorrect m->chunks updating in mbm_bw_count() in
MBM counter overflow handler, and always calling __mon_event_count() in
mbm_update() to make sure that the hardware local bandwidth counter
doesn't wrap around.

Test steps:
  # Run workload with aggressive memory bandwidth (e.g., 10 GB/s)
  git clone https://github.com/intel/intel-cmt-cat && cd intel-cmt-cat
  && make
  ./tools/membw/membw -c 0 -b 10000 --read

  # Enable MBA software controller
  mount -t resctrl resctrl -o mba_MBps /sys/fs/resctrl

  # Create control group c1
  mkdir /sys/fs/resctrl/c1

  # Set MB throttle to 6 GB/s
  echo "MB:0=6000;1=6000" > /sys/fs/resctrl/c1/schemata

  # Write PID of the workload to tasks file
  echo `pidof membw` > /sys/fs/resctrl/c1/tasks

  # Read local bytes counters twice with 1s interval, the calculated
  # local bandwidth is not as expected (approaching to 6 GB/s):
  local_1=`cat /sys/fs/resctrl/c1/mon_data/mon_L3_00/mbm_local_bytes`
  sleep 1
  local_2=`cat /sys/fs/resctrl/c1/mon_data/mon_L3_00/mbm_local_bytes`
  echo "local b/w (bytes/s):" `expr $local_2 - $local_1`

Before fix:
  local b/w (bytes/s): 11076796416

After fix:
  local b/w (bytes/s): 5465014272

Fixes: ba0f26d8529c (x86/intel_rdt/mba_sc: Prepare for feedback loop)
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/1607063279-19437-1-git-send-email-xiaochen.shen@intel.com
2020-12-10 17:52:37 +01:00
Fenghua Yu
4868a61d49 x86/resctrl: Correct MBM total and local values
Intel Memory Bandwidth Monitoring (MBM) counters may report system
memory bandwidth incorrectly on some Intel processors. The errata SKX99
for Skylake server, BDF102 for Broadwell server, and the correction
factor table are documented in Documentation/x86/resctrl.rst.

Intel MBM counters track metrics according to the assigned Resource
Monitor ID (RMID) for that logical core. The IA32_QM_CTR register
(MSR 0xC8E) used to report these metrics, may report incorrect system
bandwidth for certain RMID values.

Due to the errata, system memory bandwidth may not match what is
reported.

To work around the errata, correct MBM total and local readings using a
correction factor table. If rmid > rmid threshold, MBM total and local
values should be multiplied by the correction factor.

 [ bp: Mark mbm_cf_table[] __initdata. ]

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20201014004927.1839452-3-fenghua.yu@intel.com
2020-10-27 18:57:22 +01:00
James Morse
f995801ba3 x86/resctrl: Use container_of() in delayed_work handlers
mbm_handle_overflow() and cqm_handle_limbo() are both provided with
the domain's work_struct when called, but use get_domain_from_cpu()
to find the domain, along with the appropriate error handling.

container_of() saves some list walking and bitmap testing, use that
instead.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Link: https://lkml.kernel.org/r/20200708163929.2783-5-james.morse@arm.com
2020-08-18 17:05:08 +02:00
James Morse
abe8f12b44 x86/resctrl: Remove unused struct mbm_state::chunks_bw
Nothing reads struct mbm_states's chunks_bw value, its a copy of
chunks. Remove it.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Link: https://lkml.kernel.org/r/20200708163929.2783-2-james.morse@arm.com
2020-08-18 16:51:55 +02:00
Reinette Chatre
0c4d5ba1b9 x86/resctrl: Support wider MBM counters
The original Memory Bandwidth Monitoring (MBM) architectural
definition defines counters of up to 62 bits in the
IA32_QM_CTR MSR while the first-generation MBM implementation
uses statically defined 24 bit counters.

The MBM CPUID enumeration properties have been expanded to include
the MBM counter width, encoded as an offset from 24 bits.

While eight bits are available for the counter width offset IA32_QM_CTR
MSR only supports 62 bit counters. Add a sanity check, with warning
printed when encountered, to ensure counters cannot exceed the 62 bit
limit.

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/69d52abd5b14794d3a0f05ba7c755ed1f4c0d5ed.1588715690.git.reinette.chatre@intel.com
2020-05-06 18:08:32 +02:00
Reinette Chatre
46637d4570 x86/resctrl: Maintain MBM counter width per resource
The original Memory Bandwidth Monitoring (MBM) architectural
definition defines counters of up to 62 bits in the IA32_QM_CTR MSR,
and the first-generation MBM implementation uses 24 bit counters.
Software is required to poll at 1 second or faster to ensure that
data is retrieved before a counter rollover occurs more than once
under worst conditions.

As system bandwidths scale the software requirement is maintained with
the introduction of a per-resource enumerable MBM counter width.

In preparation for supporting hardware with an enumerable MBM counter
width the current globally static MBM counter width is moved to a
per-resource MBM counter width. Currently initialized to 24 always
to result in no functional change.

In essence there is one function, mbm_overflow_count() that needs to
know the counter width to handle rollovers. The static value
used within mbm_overflow_count() will be replaced with a value
discovered from the hardware. Support for learning the MBM counter
width from hardware is added in the change that follows.

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/e36743b9800f16ce600f86b89127391f61261f23.1588715690.git.reinette.chatre@intel.com
2020-05-06 18:00:35 +02:00
Xiaochen Shen
536a0d8e79 x86/resctrl: Check monitoring static key in the MBM overflow handler
Currently, there are three static keys in the resctrl file system:
rdt_mon_enable_key and rdt_alloc_enable_key indicate if the monitoring
feature and the allocation feature are enabled, respectively. The
rdt_enable_key is enabled when either the monitoring feature or the
allocation feature is enabled.

If no monitoring feature is present (either hardware doesn't support a
monitoring feature or the feature is disabled by the kernel command line
option "rdt="), rdt_enable_key is still enabled but rdt_mon_enable_key
is disabled.

MBM is a monitoring feature. The MBM overflow handler intends to
check if the monitoring feature is not enabled for fast return.

So check the rdt_mon_enable_key in it instead of the rdt_enable_key as
former is the more accurate check.

 [ bp: Massage commit message. ]

Fixes: e33026831bdb ("x86/intel_rdt/mbm: Handle counter overflow")
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/1576094705-13660-1-git-send-email-xiaochen.shen@intel.com
2020-01-17 19:32:32 +01:00
Linus Torvalds
963172d9c7 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
 "The accumulated fixes from this and last week:

   - Fix vmalloc TLB flush and map range calculations which lead to
     stale TLBs, spurious faults and other hard to diagnose issues.

   - Use fault_in_pages_writable() for prefaulting the user stack in the
     FPU code as it's less fragile than the current solution

   - Use the PF_KTHREAD flag when checking for a kernel thread instead
     of current->mm as the latter can give the wrong answer due to
     use_mm()

   - Compute the vmemmap size correctly for KASLR and 5-Level paging.
     Otherwise this can end up with a way too small vmemmap area.

   - Make KASAN and 5-level paging work again by making sure that all
     invalid bits are masked out when computing the P4D offset. This
     worked before but got broken recently when the LDT remap area was
     moved.

   - Prevent a NULL pointer dereference in the resource control code
     which can be triggered with certain mount options when the
     requested resource is not available.

   - Enforce ordering of microcode loading vs. perf initialization on
     secondary CPUs. Otherwise perf tries to access a non-existing MSR
     as the boot CPU marked it as available.

   - Don't stop the resource control group walk early otherwise the
     control bitmaps are not updated correctly and become inconsistent.

   - Unbreak kgdb by returning 0 on success from
     kgdb_arch_set_breakpoint() instead of an error code.

   - Add more Icelake CPU model defines so depending changes can be
     queued in other trees"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/microcode, cpuhotplug: Add a microcode loader CPU hotplug callback
  x86/kasan: Fix boot with 5-level paging and KASAN
  x86/fpu: Don't use current->mm to check for a kthread
  x86/kgdb: Return 0 from kgdb_arch_set_breakpoint()
  x86/resctrl: Prevent NULL pointer dereference when local MBM is disabled
  x86/resctrl: Don't stop walking closids when a locksetup group is found
  x86/fpu: Update kernel's FPU state before using for the fsave header
  x86/mm/KASLR: Compute the size of the vmemmap section properly
  x86/fpu: Use fault_in_pages_writeable() for pre-faulting
  x86/CPU: Add more Icelake model numbers
  mm/vmalloc: Avoid rare case of flushing TLB with weird arguments
  mm/vmalloc: Fix calculation of direct map addr range
2019-06-16 07:28:14 -10:00
Prarit Bhargava
c7563e62a6 x86/resctrl: Prevent NULL pointer dereference when local MBM is disabled
Booting with kernel parameter "rdt=cmt,mbmtotal,memlocal,l3cat,mba" and
executing "mount -t resctrl resctrl -o mba_MBps /sys/fs/resctrl" results in
a NULL pointer dereference on systems which do not have local MBM support
enabled..

BUG: kernel NULL pointer dereference, address: 0000000000000020
PGD 0 P4D 0
Oops: 0000 [#1] SMP PTI
CPU: 0 PID: 722 Comm: kworker/0:3 Not tainted 5.2.0-0.rc3.git0.1.el7_UNSUPPORTED.x86_64 #2
Workqueue: events mbm_handle_overflow
RIP: 0010:mbm_handle_overflow+0x150/0x2b0

Only enter the bandwith update loop if the system has local MBM enabled.

Fixes: de73f38f7680 ("x86/intel_rdt/mba_sc: Feedback loop to dynamically update mem bandwidth")
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190610171544.13474-1-prarit@redhat.com
2019-06-12 10:31:50 +02:00
Thomas Gleixner
2025cf9e19 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms and conditions of the gnu general public license
  version 2 as published by the free software foundation this program
  is distributed in the hope it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 263 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141901.208660670@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:36:37 +02:00
Peng Hao
7f2daa9675 x86/resctrl: Remove unused variable
Variable "struct rdt_resource *r" is set but not used. So remove it.

Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1552152584-26087-1-git-send-email-peng.hao2@zte.com.cn
2019-03-24 22:09:27 +01:00
Babu Moger
aa50453a44 x86/resctrl: Move all the macros to resctrl/internal.h
Move all the macros to resctrl/internal.h and rename the registers with
MSR_ prefix for consistency.

 [bp: align MSR definitions vertically ]

Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: "Chang S. Bae" <chang.seok.bae@intel.com>
Cc: David Miller <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dmitry Safonov <dima@arista.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: <linux-doc@vger.kernel.org>
Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Pu Wen <puwen@hygon.cn>
Cc: <qianyue.zj@alibaba-inc.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Rian Hunter <rian@alum.mit.edu>
Cc: Sherry Hurwitz <sherry.hurwitz@amd.com>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Lendacky <Thomas.Lendacky@amd.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: <xiaochen.shen@intel.com>
Link: https://lkml.kernel.org/r/20181121202811.4492-5-babu.moger@amd.com
2018-11-22 20:16:19 +01:00
Babu Moger
352940ecec x86/resctrl: Rename the RDT functions and definitions
As AMD is starting to support RESCTRL features, rename the RDT functions
and definitions to more generic names.

Replace "intel_rdt" with "resctrl" where applicable.

Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: "Chang S. Bae" <chang.seok.bae@intel.com>
Cc: David Miller <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dmitry Safonov <dima@arista.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: <linux-doc@vger.kernel.org>
Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Pu Wen <puwen@hygon.cn>
Cc: <qianyue.zj@alibaba-inc.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Rian Hunter <rian@alum.mit.edu>
Cc: Sherry Hurwitz <sherry.hurwitz@amd.com>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Lendacky <Thomas.Lendacky@amd.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: <xiaochen.shen@intel.com>
Link: https://lkml.kernel.org/r/20181121202811.4492-3-babu.moger@amd.com
2018-11-22 20:16:18 +01:00
Babu Moger
fa7d949337 x86/resctrl: Rename and move rdt files to a separate directory
New generation of AMD processors add support for RDT (or QOS) features.
Together, these features will be called RESCTRL. With more than one
vendors supporting these features, it seems more appropriate to rename
these files.

Create a new directory with the name 'resctrl' and move all the
intel_rdt files to the new directory. This way all the resctrl related
code resides inside one directory.

 [ bp: Add SPDX identifier to the Makefile ]

Suggested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: "Chang S. Bae" <chang.seok.bae@intel.com>
Cc: David Miller <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dmitry Safonov <dima@arista.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: <linux-doc@vger.kernel.org>
Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Pu Wen <puwen@hygon.cn>
Cc: <qianyue.zj@alibaba-inc.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Rian Hunter <rian@alum.mit.edu>
Cc: Sherry Hurwitz <sherry.hurwitz@amd.com>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Lendacky <Thomas.Lendacky@amd.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: <xiaochen.shen@intel.com>
Link: https://lkml.kernel.org/r/20181121202811.4492-2-babu.moger@amd.com
2018-11-22 20:16:18 +01:00