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linux/arch/powerpc/include/asm/idle.h
Michael Ellerman 18b5e7170a powerpc/pseries: Always inline functions called from cpuidle
Code in the idle path is not allowed to be instrumented because RCU is
disabled, see commit 0e985e9d22 ("cpuidle: Add comments about
noinstr/__cpuidle usage").

Force inlining of the inline functions called from cpuidle, to ensure
they are not emitted out-of-line and then available for tracing.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230406144535.3786008-4-mpe@ellerman.id.au
2023-04-20 13:21:49 +10:00

94 lines
2.4 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
#ifndef _ASM_POWERPC_IDLE_H
#define _ASM_POWERPC_IDLE_H
#include <asm/runlatch.h>
#include <asm/paca.h>
#ifdef CONFIG_PPC_PSERIES
DECLARE_PER_CPU(u64, idle_spurr_cycles);
DECLARE_PER_CPU(u64, idle_entry_purr_snap);
DECLARE_PER_CPU(u64, idle_entry_spurr_snap);
static __always_inline void snapshot_purr_idle_entry(void)
{
*this_cpu_ptr(&idle_entry_purr_snap) = mfspr(SPRN_PURR);
}
static __always_inline void snapshot_spurr_idle_entry(void)
{
*this_cpu_ptr(&idle_entry_spurr_snap) = mfspr(SPRN_SPURR);
}
static __always_inline void update_idle_purr_accounting(void)
{
u64 wait_cycles;
u64 in_purr = *this_cpu_ptr(&idle_entry_purr_snap);
wait_cycles = be64_to_cpu(get_lppaca()->wait_state_cycles);
wait_cycles += mfspr(SPRN_PURR) - in_purr;
get_lppaca()->wait_state_cycles = cpu_to_be64(wait_cycles);
}
static __always_inline void update_idle_spurr_accounting(void)
{
u64 *idle_spurr_cycles_ptr = this_cpu_ptr(&idle_spurr_cycles);
u64 in_spurr = *this_cpu_ptr(&idle_entry_spurr_snap);
*idle_spurr_cycles_ptr += mfspr(SPRN_SPURR) - in_spurr;
}
static __always_inline void pseries_idle_prolog(void)
{
ppc64_runlatch_off();
snapshot_purr_idle_entry();
snapshot_spurr_idle_entry();
/*
* Indicate to the HV that we are idle. Now would be
* a good time to find other work to dispatch.
*/
get_lppaca()->idle = 1;
}
static __always_inline void pseries_idle_epilog(void)
{
update_idle_purr_accounting();
update_idle_spurr_accounting();
get_lppaca()->idle = 0;
ppc64_runlatch_on();
}
static inline u64 read_this_idle_purr(void)
{
/*
* If we are reading from an idle context, update the
* idle-purr cycles corresponding to the last idle period.
* Since the idle context is not yet over, take a fresh
* snapshot of the idle-purr.
*/
if (unlikely(get_lppaca()->idle == 1)) {
update_idle_purr_accounting();
snapshot_purr_idle_entry();
}
return be64_to_cpu(get_lppaca()->wait_state_cycles);
}
static inline u64 read_this_idle_spurr(void)
{
/*
* If we are reading from an idle context, update the
* idle-spurr cycles corresponding to the last idle period.
* Since the idle context is not yet over, take a fresh
* snapshot of the idle-spurr.
*/
if (get_lppaca()->idle == 1) {
update_idle_spurr_accounting();
snapshot_spurr_idle_entry();
}
return *this_cpu_ptr(&idle_spurr_cycles);
}
#endif /* CONFIG_PPC_PSERIES */
#endif