In ACPI processor drivers, we use direct comparisons of cpu logical id with -1 which are error prone in case logical cpuid is accidentally assinged an error code and prevents us from returning an error-encoding cpuid directly in some cases.
So introduce invalid_logical_cpuid() to identify cpu with invalid logical cpu num, then it will be used to replace the direct comparisons with -1.
Signed-off-by: Hanjun Guo hanjun.guo@linaro.org --- drivers/acpi/acpi_processor.c | 5 +++-- drivers/acpi/processor_pdc.c | 5 +---- include/linux/acpi.h | 5 +++++ 3 files changed, 9 insertions(+), 6 deletions(-)
diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c index 58f335c..ac6bda0 100644 --- a/drivers/acpi/acpi_processor.c +++ b/drivers/acpi/acpi_processor.c @@ -275,7 +275,8 @@ static int acpi_processor_get_info(struct acpi_device *device) * Handle UP system running SMP kernel, with no CPU * entry in MADT */ - if ((cpu_index == -1) && (num_online_cpus() == 1)) + if (invalid_logical_cpuid(cpu_index) + && (num_online_cpus() == 1)) cpu_index = 0; } pr->id = cpu_index; @@ -285,7 +286,7 @@ static int acpi_processor_get_info(struct acpi_device *device) * less than the max # of CPUs. They should be ignored _iff * they are physically not present. */ - if (pr->id == -1) { + if (invalid_logical_cpuid(pr->id)) { int ret = acpi_processor_hotadd_init(pr); if (ret) return ret; diff --git a/drivers/acpi/processor_pdc.c b/drivers/acpi/processor_pdc.c index e5dd808..7cfbda4 100644 --- a/drivers/acpi/processor_pdc.c +++ b/drivers/acpi/processor_pdc.c @@ -52,10 +52,7 @@ static bool __init processor_physically_present(acpi_handle handle) type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0; cpuid = acpi_get_cpuid(handle, type, acpi_id);
- if (cpuid == -1) - return false; - - return true; + return !invalid_logical_cpuid(cpuid); }
static void acpi_set_pdc_bits(u32 *buf) diff --git a/include/linux/acpi.h b/include/linux/acpi.h index e4da5e3..913b49f 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -158,6 +158,11 @@ typedef u32 phys_cpuid_t; #define PHYS_CPUID_INVALID (phys_cpuid_t)(-1) #endif
+static inline bool invalid_logical_cpuid(u32 cpuid) +{ + return (int)cpuid < 0; +} + #ifdef CONFIG_ACPI_HOTPLUG_CPU /* Arch dependent functions for cpu hotplug support */ int acpi_map_cpu(acpi_handle handle, phys_cpuid_t physid, int *pcpu);