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| author | Nicholas Piggin <npiggin@gmail.com> | 2018-05-05 03:19:30 +1000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2018-06-03 20:40:27 +1000 |
| commit | 3d3a6021ddcbe9c31520e4e7b65e5ce5dc58274d (patch) | |
| tree | 10d300ac9f4f3b8354b9e35075d3d5a776739e7e /arch/powerpc/kernel/process.c | |
| parent | 36d632ea831fd2fa3cb62599a465825f59076f64 (diff) | |
| download | linux-3d3a6021ddcbe9c31520e4e7b65e5ce5dc58274d.tar.gz | |
powerpc/pseries: lparcfg calculate PURR on demand
For SPLPAR, lparcfg provides a sum of PURR registers for all CPUs.
Currently this is done by reading PURR in context switch and timer
interrupt, and storing that into a per-CPU variable. These are summed
to provide the value.
This does not work with all timer schemes (e.g., NO_HZ_FULL), and it
is sub-optimal for performance because it reads the PURR register on
every context switch, although that's been difficult to distinguish
from noise in the contxt_switch microbenchmark.
This patch implements the sum by calling a function on each CPU, to
read and add PURR values of each CPU.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/kernel/process.c')
| -rw-r--r-- | arch/powerpc/kernel/process.c | 14 |
1 files changed, 0 insertions, 14 deletions
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index f4e5291584c55..2a7fa5000ccec 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -846,10 +846,6 @@ bool ppc_breakpoint_available(void) } EXPORT_SYMBOL_GPL(ppc_breakpoint_available); -#ifdef CONFIG_PPC64 -DEFINE_PER_CPU(struct cpu_usage, cpu_usage_array); -#endif - static inline bool hw_brk_match(struct arch_hw_breakpoint *a, struct arch_hw_breakpoint *b) { @@ -1182,16 +1178,6 @@ struct task_struct *__switch_to(struct task_struct *prev, WARN_ON(!irqs_disabled()); -#ifdef CONFIG_PPC64 - /* - * Collect processor utilization data per process - */ - if (firmware_has_feature(FW_FEATURE_SPLPAR)) { - struct cpu_usage *cu = this_cpu_ptr(&cpu_usage_array); - cu->current_tb = mfspr(SPRN_PURR); - } -#endif /* CONFIG_PPC64 */ - #ifdef CONFIG_PPC_BOOK3S_64 batch = this_cpu_ptr(&ppc64_tlb_batch); if (batch->active) { |