3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Peter Zijlstra <peterz@xxxxxxxxxxxxx> commit 1b45adcd9a503428e6de6b39bc6892d86c9c1d41 upstream. Josh reported that his QEMU is a bad hardware emulator and trips a WARN in the AMD PMU init code. He requested the WARN be turned into a pr_err() or similar. While there, rework the code a little. Reported-by: Josh Boyer <jwboyer@xxxxxxxxxx> Acked-by: Robert Richter <rric@xxxxxxxxxx> Acked-by: Jacob Shin <jacob.shin@xxxxxxx> Cc: Stephane Eranian <eranian@xxxxxxxxxx> Signed-off-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/20130521110537.GG26912@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Guenter Roeck <linux@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/kernel/cpu/perf_event_amd.c | 34 +++++++++++++++++----------------- 1 file changed, 17 insertions(+), 17 deletions(-) --- a/arch/x86/kernel/cpu/perf_event_amd.c +++ b/arch/x86/kernel/cpu/perf_event_amd.c @@ -648,48 +648,48 @@ static __initconst const struct x86_pmu .cpu_dead = amd_pmu_cpu_dead, }; -static int setup_event_constraints(void) +static int __init amd_core_pmu_init(void) { - if (boot_cpu_data.x86 == 0x15) + if (!cpu_has_perfctr_core) + return 0; + + switch (boot_cpu_data.x86) { + case 0x15: + pr_cont("Fam15h "); x86_pmu.get_event_constraints = amd_get_event_constraints_f15h; - return 0; -} + break; -static int setup_perfctr_core(void) -{ - if (!cpu_has_perfctr_core) { - WARN(x86_pmu.get_event_constraints == amd_get_event_constraints_f15h, - KERN_ERR "Odd, counter constraints enabled but no core perfctrs detected!"); + default: + pr_err("core perfctr but no constraints; unknown hardware!\n"); return -ENODEV; } - WARN(x86_pmu.get_event_constraints == amd_get_event_constraints, - KERN_ERR "hw perf events core counters need constraints handler!"); - /* * If core performance counter extensions exists, we must use * MSR_F15H_PERF_CTL/MSR_F15H_PERF_CTR msrs. See also - * x86_pmu_addr_offset(). + * amd_pmu_addr_offset(). */ x86_pmu.eventsel = MSR_F15H_PERF_CTL; x86_pmu.perfctr = MSR_F15H_PERF_CTR; x86_pmu.num_counters = AMD64_NUM_COUNTERS_CORE; - printk(KERN_INFO "perf: AMD core performance counters detected\n"); - + pr_cont("core perfctr, "); return 0; } __init int amd_pmu_init(void) { + int ret; + /* Performance-monitoring supported from K7 and later: */ if (boot_cpu_data.x86 < 6) return -ENODEV; x86_pmu = amd_pmu; - setup_event_constraints(); - setup_perfctr_core(); + ret = amd_core_pmu_init(); + if (ret) + return ret; /* Events are common for all AMDs */ memcpy(hw_cache_event_ids, amd_hw_cache_event_ids, -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html