x86/itmt: Move the "sched_itmt_enabled" sysctl to debugfs

"sched_itmt_enabled" was only introduced as a debug toggle for any funky
ITMT behavior. Move the sysctl controlled from
"/proc/sys/kernel/sc

x86/itmt: Move the "sched_itmt_enabled" sysctl to debugfs

"sched_itmt_enabled" was only introduced as a debug toggle for any funky
ITMT behavior. Move the sysctl controlled from
"/proc/sys/kernel/sched_itmt_enabled" to debugfs at
"/sys/kernel/debug/x86/sched_itmt_enabled" with a notable change that a
cat on the file will return "Y" or "N" instead of "1" or "0" to
indicate that feature is enabled or disabled respectively. Either "0" or
"N" (or any string that kstrtobool() interprets as false) can be written
to the file will disable the feature, and writing either "1" or "Y" (or
any string that kstrtobool() interprets as true) will enable it back
when the platform supports ITMT ranking.

Since ITMT is x86 specific (and PowerPC uses SD_ASYM_PACKING too), the
toggle was moved to "/sys/kernel/debug/x86/" as opposed to
"/sys/kernel/debug/sched/"

Suggested-by: Peter Zijlstra <[email protected]>
Signed-off-by: K Prateek Nayak <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Tim Chen <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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x86/itmt: Use guard() for itmt_update_mutex

Use guard() for itmt_update_mutex which avoids the extra mutex_unlock()
in the bailout and return paths.

Signed-off-by: K Prateek Nayak <kprateek.nayak@a

x86/itmt: Use guard() for itmt_update_mutex

Use guard() for itmt_update_mutex which avoids the extra mutex_unlock()
in the bailout and return paths.

Signed-off-by: K Prateek Nayak <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Tim Chen <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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x86/itmt: Convert "sysctl_sched_itmt_enabled" to boolean

In preparation to move "sysctl_sched_itmt_enabled" to debugfs, convert
the unsigned int to bool since debugfs readily exposes boolean fops
pr

x86/itmt: Convert "sysctl_sched_itmt_enabled" to boolean

In preparation to move "sysctl_sched_itmt_enabled" to debugfs, convert
the unsigned int to bool since debugfs readily exposes boolean fops
primitives (debugfs_read_file_bool, debugfs_write_file_bool) which can
streamline the conversion.

Since the current ctl_table initializes extra1 and extra2 to SYSCTL_ZERO
and SYSCTL_ONE respectively, the value of "sysctl_sched_itmt_enabled"
can only be 0 or 1 and this datatype conversion should not cause any
functional changes.

Signed-off-by: K Prateek Nayak <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Tim Chen <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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sysctl: treewide: constify the ctl_table argument of proc_handlers

const qualify the struct ctl_table argument in the proc_handler function
signatures. This is a prerequisite to moving the static ct

sysctl: treewide: constify the ctl_table argument of proc_handlers

const qualify the struct ctl_table argument in the proc_handler function
signatures. This is a prerequisite to moving the static ctl_table
structs into .rodata data which will ensure that proc_handler function
pointers cannot be modified.

This patch has been generated by the following coccinelle script:

```
virtual patch

@r1@
identifier ctl, write, buffer, lenp, ppos;
identifier func !~ "appldata_(timer|interval)_handler|sched_(rt|rr)_handler|rds_tcp_skbuf_handler|proc_sctp_do_(hmac_alg|rto_min|rto_max|udp_port|alpha_beta|auth|probe_interval)";
@@

int func(
- struct ctl_table *ctl
+ const struct ctl_table *ctl
,int write, void *buffer, size_t *lenp, loff_t *ppos);

@r2@
identifier func, ctl, write, buffer, lenp, ppos;
@@

int func(
- struct ctl_table *ctl
+ const struct ctl_table *ctl
,int write, void *buffer, size_t *lenp, loff_t *ppos)
{ ... }

@r3@
identifier func;
@@

int func(
- struct ctl_table *
+ const struct ctl_table *
,int , void *, size_t *, loff_t *);

@r4@
identifier func, ctl;
@@

int func(
- struct ctl_table *ctl
+ const struct ctl_table *ctl
,int , void *, size_t *, loff_t *);

@r5@
identifier func, write, buffer, lenp, ppos;
@@

int func(
- struct ctl_table *
+ const struct ctl_table *
,int write, void *buffer, size_t *lenp, loff_t *ppos);

```

* Code formatting was adjusted in xfs_sysctl.c to comply with code
conventions. The xfs_stats_clear_proc_handler,
xfs_panic_mask_proc_handler and xfs_deprecated_dointvec_minmax where
adjusted.

* The ctl_table argument in proc_watchdog_common was const qualified.
This is called from a proc_handler itself and is calling back into
another proc_handler, making it necessary to change it as part of the
proc_handler migration.

Co-developed-by: Thomas Weißschuh <[email protected]>
Signed-off-by: Thomas Weißschuh <[email protected]>
Co-developed-by: Joel Granados <[email protected]>
Signed-off-by: Joel Granados <[email protected]>

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arch/x86: Remove now superfluous sentinel elem from ctl_table arrays

This commit comes at the tail end of a greater effort to remove the
empty elements at the end of the ctl_table arrays (sentinels)

arch/x86: Remove now superfluous sentinel elem from ctl_table arrays

This commit comes at the tail end of a greater effort to remove the
empty elements at the end of the ctl_table arrays (sentinels) which
will reduce the overall build time size of the kernel and run time
memory bloat by ~64 bytes per sentinel (further information Link :
https://lore.kernel.org/all/ZO5Yx5JFogGi%[email protected]/)

Remove sentinel element from sld_sysctl and itmt_kern_table. This
removal is safe because register_sysctl_init and register_sysctl
implicitly use the array size in addition to checking for the sentinel.

Reviewed-by: Ingo Molnar <[email protected]>
Acked-by: Dave Hansen <[email protected]> # for x86
Signed-off-by: Joel Granados <[email protected]>
Signed-off-by: Luis Chamberlain <[email protected]>

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x86/sched/itmt: Give all SMT siblings of a core the same priority

X86 does not have the SD_ASYM_PACKING flag in the SMT domain. The scheduler
knows how to handle SMT and non-SMT cores of different p

x86/sched/itmt: Give all SMT siblings of a core the same priority

X86 does not have the SD_ASYM_PACKING flag in the SMT domain. The scheduler
knows how to handle SMT and non-SMT cores of different priority. There is
no reason for SMT siblings of a core to have different priorities.

Signed-off-by: Ricardo Neri <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Len Brown <[email protected]>
Tested-by: Zhang Rui <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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x86: Simplify one-level sysctl registration for itmt_kern_table

There is no need to declare an extra tables to just create directory,
this can be easily be done with a prefix path with register_sysc

x86: Simplify one-level sysctl registration for itmt_kern_table

There is no need to declare an extra tables to just create directory,
this can be easily be done with a prefix path with register_sysctl().

Simplify this registration.

Signed-off-by: Luis Chamberlain <[email protected]>
Signed-off-by: Dave Hansen <[email protected]>
Link: https://lore.kernel.org/all/20230310233248.3965389-3-mcgrof%40kernel.org

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x86/sched: Decrease further the priorities of SMT siblings

When scheduling, it is better to prefer a separate physical core rather
than the SMT sibling of a high priority core. The existing formula

x86/sched: Decrease further the priorities of SMT siblings

When scheduling, it is better to prefer a separate physical core rather
than the SMT sibling of a high priority core. The existing formula to
compute priorities takes such fact in consideration. There may exist,
however, combinations of priorities (i.e., maximum frequencies) in which
the priority of high-numbered SMT siblings of high-priority cores collides
with the priority of low-numbered SMT siblings of low-priority cores.

Consider for instance an SMT2 system with CPUs [0, 1] with priority 60 and
[2, 3] with priority 30(CPUs in brackets are SMT siblings. In such a case,
the resulting priorities would be [120, 60], [60, 30]. Thus, to ensure
that CPU2 has higher priority than CPU1, divide the raw priority by the
squared SMT iterator. The resulting priorities are [120, 30]. [60, 15].

Originally-by: Len Brown <[email protected]>
Signed-off-by: Len Brown <[email protected]>
Signed-off-by: Ricardo Neri <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

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sysctl: pass kernel pointers to ->proc_handler

Instead of having all the sysctl handlers deal with user pointers, which
is rather hairy in terms of the BPF interaction, copy the input to and
from u

sysctl: pass kernel pointers to ->proc_handler

Instead of having all the sysctl handlers deal with user pointers, which
is rather hairy in terms of the BPF interaction, copy the input to and
from userspace in common code. This also means that the strings are
always NUL-terminated by the common code, making the API a little bit
safer.

As most handler just pass through the data to one of the common handlers
a lot of the changes are mechnical.

Signed-off-by: Christoph Hellwig <[email protected]>
Acked-by: Andrey Ignatov <[email protected]>
Signed-off-by: Al Viro <[email protected]>

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proc/sysctl: add shared variables for range check

In the sysctl code the proc_dointvec_minmax() function is often used to
validate the user supplied value between an allowed range. This
function us

proc/sysctl: add shared variables for range check

In the sysctl code the proc_dointvec_minmax() function is often used to
validate the user supplied value between an allowed range. This
function uses the extra1 and extra2 members from struct ctl_table as
minimum and maximum allowed value.

On sysctl handler declaration, in every source file there are some
readonly variables containing just an integer which address is assigned
to the extra1 and extra2 members, so the sysctl range is enforced.

The special values 0, 1 and INT_MAX are very often used as range
boundary, leading duplication of variables like zero=0, one=1,
int_max=INT_MAX in different source files:

$ git grep -E '\.extra[12].*&(zero|one|int_max)' |wc -l
248

Add a const int array containing the most commonly used values, some
macros to refer more easily to the correct array member, and use them
instead of creating a local one for every object file.

This is the bloat-o-meter output comparing the old and new binary
compiled with the default Fedora config:

# scripts/bloat-o-meter -d vmlinux.o.old vmlinux.o
add/remove: 2/2 grow/shrink: 0/2 up/down: 24/-188 (-164)
Data old new delta
sysctl_vals - 12 +12
__kstrtab_sysctl_vals - 12 +12
max 14 10 -4
int_max 16 - -16
one 68 - -68
zero 128 28 -100
Total: Before=20583249, After=20583085, chg -0.00%

[[email protected]: tipc: remove two unused variables]
Link: http://lkml.kernel.org/r/[email protected]
[[email protected]: fix net/ipv6/sysctl_net_ipv6.c]
[[email protected]: proc/sysctl: make firmware loader table conditional]
Link: http://lkml.kernel.org/r/[email protected]
[[email protected]: fix fs/eventpoll.c]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Matteo Croce <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>
Acked-by: Kees Cook <[email protected]>
Reviewed-by: Aaron Tomlin <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Stephen Rothwell <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of th

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation version 2 of the license

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 315 file(s).

Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Allison Randal <[email protected]>
Reviewed-by: Armijn Hemel <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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x86/headers: Remove duplicate #includes

These duplicate includes have been found with scripts/checkincludes.pl but
they have been removed manually to avoid removing false positives.

Signed-off-by:

x86/headers: Remove duplicate #includes

These duplicate includes have been found with scripts/checkincludes.pl but
they have been removed manually to avoid removing false positives.

Signed-off-by: Pravin Shedge <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

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sched/x86: Remove unnecessary TBM3 check to update topology

Scheduling to the max performance core is enabled by
default for Turbo Boost Maxt Technology 3.0 capable platforms.

Remove the useless sy

sched/x86: Remove unnecessary TBM3 check to update topology

Scheduling to the max performance core is enabled by
default for Turbo Boost Maxt Technology 3.0 capable platforms.

Remove the useless sysctl_sched_itmt_enabled check to
update sched topology for adding the prioritized core scheduling
flag.

Signed-off-by: Tim Chen <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Srinivas Pandruvada <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

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x86/sched: Use #include <linux/mutex.h> instead of #include <asm/mutex.h>

asm/mutex.h is gone from the locking tree, which makes sched/core break the build.

Use linux/mutex.h instead, which is the

x86/sched: Use #include <linux/mutex.h> instead of #include <asm/mutex.h>

asm/mutex.h is gone from the locking tree, which makes sched/core break the build.

Use linux/mutex.h instead, which is the canonical method.

Cc: Srinivas Pandruvada <[email protected]>
Cc: Rafael J. Wysocki <[email protected]>
Cc: Tim Chen <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: Thomas Gleixner <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>

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x86/sysctl: Add sysctl for ITMT scheduling feature

Intel Turbo Boost Max Technology 3.0 (ITMT) feature
allows some cores to be boosted to higher turbo
frequency than others.

Add /proc/sys/kernel/sc

x86/sysctl: Add sysctl for ITMT scheduling feature

Intel Turbo Boost Max Technology 3.0 (ITMT) feature
allows some cores to be boosted to higher turbo
frequency than others.

Add /proc/sys/kernel/sched_itmt_enabled so operator
can enable/disable scheduling of tasks that favor cores
with higher turbo boost frequency potential.

By default, system that is ITMT capable and single
socket has this feature turned on. It is more likely
to be lightly loaded and operates in Turbo range.

When there is a change in the ITMT scheduling operation
desired, a rebuild of the sched domain is initiated
so the scheduler can set up sched domains with appropriate
flag to enable/disable ITMT scheduling operations.

Co-developed-by: Peter Zijlstra (Intel) <[email protected]>
Co-developed-by: Srinivas Pandruvada <[email protected]>
Signed-off-by: Tim Chen <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: Srinivas Pandruvada <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/07cc62426a28bad57b01ab16bb903a9c84fa5421.1479844244.git.tim.c.chen@linux.intel.com
Signed-off-by: Thomas Gleixner <[email protected]>

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x86: Enable Intel Turbo Boost Max Technology 3.0

On platforms supporting Intel Turbo Boost Max Technology 3.0, the maximum
turbo frequencies of some cores in a CPU package may be higher than for
the

x86: Enable Intel Turbo Boost Max Technology 3.0

On platforms supporting Intel Turbo Boost Max Technology 3.0, the maximum
turbo frequencies of some cores in a CPU package may be higher than for
the other cores in the same package. In that case, better performance
(and possibly lower energy consumption as well) can be achieved by
making the scheduler prefer to run tasks on the CPUs with higher max
turbo frequencies.

To that end, set up a core priority metric to abstract the core
preferences based on the maximum turbo frequency. In that metric,
the cores with higher maximum turbo frequencies are higher-priority
than the other cores in the same package and that causes the scheduler
to favor them when making load-balancing decisions using the asymmertic
packing approach. At the same time, the priority of SMT threads with a
higher CPU number is reduced so as to avoid scheduling tasks on all of
the threads that belong to a favored core before all of the other cores
have been given a task to run.

The priority metric will be initialized by the P-state driver with the
help of the sched_set_itmt_core_prio() function. The P-state driver
will also determine whether or not ITMT is supported by the platform
and will call sched_set_itmt_support() to indicate that.

Co-developed-by: Peter Zijlstra (Intel) <[email protected]>
Co-developed-by: Srinivas Pandruvada <[email protected]>
Signed-off-by: Tim Chen <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: Srinivas Pandruvada <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/cd401ccdff88f88c8349314febdc25d51f7c48f7.1479844244.git.tim.c.chen@linux.intel.com
Signed-off-by: Thomas Gleixner <[email protected]>

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