From e4a884cc28fa3f5d8b81de46998ffe29b4ad169e Mon Sep 17 00:00:00 2001 From: "Gautham R. Shenoy" Date: Tue, 7 Apr 2020 14:17:39 +0530 Subject: [PATCH] powerpc: Move idle_loop_prolog()/epilog() functions to header file Currently prior to entering an idle state on a Linux Guest, the pseries cpuidle driver implement an idle_loop_prolog() and idle_loop_epilog() functions which ensure that idle_purr is correctly computed, and the hypervisor is informed that the CPU cycles have been donated. These prolog and epilog functions are also required in the default idle call, i.e pseries_lpar_idle(). Hence move these accessor functions to a common header file and call them from pseries_lpar_idle(). Since the existing header files such as asm/processor.h have enough clutter, create a new header file asm/idle.h. Finally rename idle_loop_prolog() and idle_loop_epilog() to pseries_idle_prolog() and pseries_idle_epilog() as they are only relavent for on pseries guests. Signed-off-by: Gautham R. Shenoy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/1586249263-14048-2-git-send-email-ego@linux.vnet.ibm.com --- arch/powerpc/include/asm/idle.h | 31 +++++++++++++++++++++++++++++ arch/powerpc/platforms/pseries/setup.c | 7 +++++-- drivers/cpuidle/cpuidle-pseries.c | 36 +++++++--------------------------- 3 files changed, 43 insertions(+), 31 deletions(-) create mode 100644 arch/powerpc/include/asm/idle.h diff --git a/arch/powerpc/include/asm/idle.h b/arch/powerpc/include/asm/idle.h new file mode 100644 index 000000000000..32064a4c0dd7 --- /dev/null +++ b/arch/powerpc/include/asm/idle.h @@ -0,0 +1,31 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef _ASM_POWERPC_IDLE_H +#define _ASM_POWERPC_IDLE_H +#include +#include + +#ifdef CONFIG_PPC_PSERIES +static inline void pseries_idle_prolog(unsigned long *in_purr) +{ + ppc64_runlatch_off(); + *in_purr = mfspr(SPRN_PURR); + /* + * 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 inline void pseries_idle_epilog(unsigned long in_purr) +{ + u64 wait_cycles; + + 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); + get_lppaca()->idle = 0; + + ppc64_runlatch_on(); +} +#endif /* CONFIG_PPC_PSERIES */ +#endif diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c index 0c8421dd01ab..2f53e6b031a7 100644 --- a/arch/powerpc/platforms/pseries/setup.c +++ b/arch/powerpc/platforms/pseries/setup.c @@ -68,6 +68,7 @@ #include #include #include +#include #include #include @@ -319,6 +320,8 @@ machine_early_initcall(pseries, alloc_dispatch_log_kmem_cache); static void pseries_lpar_idle(void) { + unsigned long in_purr; + /* * Default handler to go into low thread priority and possibly * low power mode by ceding processor to hypervisor @@ -328,7 +331,7 @@ static void pseries_lpar_idle(void) return; /* Indicate to hypervisor that we are idle. */ - get_lppaca()->idle = 1; + pseries_idle_prolog(&in_purr); /* * Yield the processor to the hypervisor. We return if @@ -339,7 +342,7 @@ static void pseries_lpar_idle(void) */ cede_processor(); - get_lppaca()->idle = 0; + pseries_idle_epilog(in_purr); } /* diff --git a/drivers/cpuidle/cpuidle-pseries.c b/drivers/cpuidle/cpuidle-pseries.c index 74c247972bb3..46d5e05fcf97 100644 --- a/drivers/cpuidle/cpuidle-pseries.c +++ b/drivers/cpuidle/cpuidle-pseries.c @@ -19,6 +19,7 @@ #include #include #include +#include #include struct cpuidle_driver pseries_idle_driver = { @@ -31,29 +32,6 @@ static struct cpuidle_state *cpuidle_state_table __read_mostly; static u64 snooze_timeout __read_mostly; static bool snooze_timeout_en __read_mostly; -static inline void idle_loop_prolog(unsigned long *in_purr) -{ - ppc64_runlatch_off(); - *in_purr = mfspr(SPRN_PURR); - /* - * 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 inline void idle_loop_epilog(unsigned long in_purr) -{ - u64 wait_cycles; - - 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); - get_lppaca()->idle = 0; - - ppc64_runlatch_on(); -} - static int snooze_loop(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index) @@ -63,7 +41,7 @@ static int snooze_loop(struct cpuidle_device *dev, set_thread_flag(TIF_POLLING_NRFLAG); - idle_loop_prolog(&in_purr); + pseries_idle_prolog(&in_purr); local_irq_enable(); snooze_exit_time = get_tb() + snooze_timeout; @@ -87,7 +65,7 @@ static int snooze_loop(struct cpuidle_device *dev, local_irq_disable(); - idle_loop_epilog(in_purr); + pseries_idle_epilog(in_purr); return index; } @@ -115,7 +93,7 @@ static int dedicated_cede_loop(struct cpuidle_device *dev, { unsigned long in_purr; - idle_loop_prolog(&in_purr); + pseries_idle_prolog(&in_purr); get_lppaca()->donate_dedicated_cpu = 1; HMT_medium(); @@ -124,7 +102,7 @@ static int dedicated_cede_loop(struct cpuidle_device *dev, local_irq_disable(); get_lppaca()->donate_dedicated_cpu = 0; - idle_loop_epilog(in_purr); + pseries_idle_epilog(in_purr); return index; } @@ -135,7 +113,7 @@ static int shared_cede_loop(struct cpuidle_device *dev, { unsigned long in_purr; - idle_loop_prolog(&in_purr); + pseries_idle_prolog(&in_purr); /* * Yield the processor to the hypervisor. We return if @@ -147,7 +125,7 @@ static int shared_cede_loop(struct cpuidle_device *dev, check_and_cede_processor(); local_irq_disable(); - idle_loop_epilog(in_purr); + pseries_idle_epilog(in_purr); return index; } -- 2.11.0