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| author |   James Morse <james.morse@arm.com> | 2024-02-13 18:44:15 +0000 |
|---|---|---|
| committer |   Borislav Petkov (AMD) <bp@alien8.de> | 2024-02-16 19:18:31 +0100 |
| commit | 31a5c0b7c674977889ce721d69101bc35f25e041 (patch) | |
| tree | 5ddeafb18e893f63f92364bc10eacd26d7f53b6d /include/linux/tick.h | |
| parent | x86/resctrl: Remove redundant variable in mbm_config_write_domain() (diff) | |
| download | wireguard-linux-31a5c0b7c674977889ce721d69101bc35f25e041.tar.xz wireguard-linux-31a5c0b7c674977889ce721d69101bc35f25e041.zip | |
tick/nohz: Move tick_nohz_full_mask declaration outside the #ifdef
tick_nohz_full_mask lists the CPUs that are nohz_full. This is only needed when
CONFIG_NO_HZ_FULL is defined. tick_nohz_full_cpu() allows a specific CPU to be
tested against the mask, and evaluates to false when CONFIG_NO_HZ_FULL is not
defined.
The resctrl code needs to pick a CPU to run some work on, a new helper prefers
housekeeping CPUs by examining the tick_nohz_full_mask. Hiding the declaration
behind #ifdef CONFIG_NO_HZ_FULL forces all the users to be behind an #ifdef
too.
Move the tick_nohz_full_mask declaration, this lets callers drop the #ifdef,
and guard access to tick_nohz_full_mask with IS_ENABLED() or something like
tick_nohz_full_cpu().
The definition does not need to be moved as any callers should be removed at
compile time unless CONFIG_NO_HZ_FULL is defined.
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Reinette Chatre <reinette.chatre@intel.com> # for resctrl dependency
Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Link: https://lore.kernel.org/r/20240213184438.16675-2-james.morse@arm.com
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Diffstat (limited to 'include/linux/tick.h')
| -rw-r--r-- | include/linux/tick.h | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/include/linux/tick.h b/include/linux/tick.h index 716d17f31c45..0fb903838dfb 100644 --- a/include/linux/tick.h +++ b/include/linux/tick.h @@ -164,9 +164,16 @@ static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; } static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; } #endif /* !CONFIG_NO_HZ_COMMON */ +/* + * Mask of CPUs that are nohz_full. + * + * Users should be guarded by CONFIG_NO_HZ_FULL or a tick_nohz_full_cpu() + * check. + */ +extern cpumask_var_t tick_nohz_full_mask; + #ifdef CONFIG_NO_HZ_FULL extern bool tick_nohz_full_running; -extern cpumask_var_t tick_nohz_full_mask; static inline bool tick_nohz_full_enabled(void) { |