Re: [PATCH] fix stolen time for SMT without LPAR
From: Michael Neuling <hidden>
Date: 2007-05-25 05:08:31
For POWERPC, stolen time accounts for cycles lost to the hypervisor or PURR cycles attributed to the other SMT thread. Hence, when a PURR is available, we should still calculate stolen time, irrespective of being virtualised. Signed-off-by: Michael Neuling <redacted> --- Updated to fix link error when CONFIG_PPC_SPLPAR is off. arch/powerpc/kernel/time.c | 8 +++++--- include/asm-powerpc/time.h | 2 +- 2 files changed, 6 insertions(+), 4 deletions(-) Index: linux-2.6-ozlabs/arch/powerpc/kernel/time.c ===================================================================
--- linux-2.6-ozlabs.orig/arch/powerpc/kernel/time.c
+++ linux-2.6-ozlabs/arch/powerpc/kernel/time.c@@ -214,7 +214,6 @@ static void account_process_time(struct run_posix_cpu_timers(current); } -#ifdef CONFIG_PPC_SPLPAR /* * Stuff for accounting stolen time. */
@@ -244,7 +243,8 @@ void snapshot_timebases(void) { int cpu; - if (!cpu_has_feature(CPU_FTR_PURR)) + if (!cpu_has_feature(CPU_FTR_PURR) && + !firmware_has_feature(FW_FEATURE_SPLPAR)) return; for_each_possible_cpu(cpu) spin_lock_init(&per_cpu(cpu_purr_data, cpu).lock);
@@ -257,7 +257,8 @@ void calculate_steal_time(void) s64 stolen; struct cpu_purr_data *pme; - if (!cpu_has_feature(CPU_FTR_PURR)) + if (!cpu_has_feature(CPU_FTR_PURR) && + !firmware_has_feature(FW_FEATURE_SPLPAR)) return; pme = &per_cpu(cpu_purr_data, smp_processor_id()); if (!pme->initialized)
@@ -273,6 +274,7 @@ void calculate_steal_time(void) spin_unlock(&pme->lock); } +#ifdef CONFIG_PPC_SPLPAR /* * Must be called before the cpu is added to the online map when * a cpu is being brought up at runtime.
Index: linux-2.6-ozlabs/include/asm-powerpc/time.h ===================================================================
--- linux-2.6-ozlabs.orig/include/asm-powerpc/time.h
+++ linux-2.6-ozlabs/include/asm-powerpc/time.h@@ -232,7 +232,7 @@ extern void account_process_vtime(struct #define account_process_vtime(tsk) do { } while (0) #endif -#if defined(CONFIG_VIRT_CPU_ACCOUNTING) && defined(CONFIG_PPC_SPLPAR) +#if defined(CONFIG_VIRT_CPU_ACCOUNTING) extern void calculate_steal_time(void); extern void snapshot_timebases(void); #else