When cpumask_next() the return value is greater than or equal to
nr_cpu_ids, it indicates invalid.
Before commit 596ff4a09b89 ("cpumask: re-introduce constant-sized cpumask
optimizations"), when cpumask_next() returned an invalid cpu, the driver
used the judgment equal to nr_cpu_ids to indicate the invalid cpu, so it
happened to work normally, but this is the wrong approach.
After commit 596ff4a09b89 ("cpumask: re-introduce constant-sized cpumask
optimizations"), these incorrect practices actively buggy, so fix it to
correctly.
Signed-off-by: Vernon Yang <vernon2gm@xxxxxxxxx>
---
drivers/scsi/lpfc/lpfc_init.c | 43 ++++++++++++++++-------------------
1 file changed, 20 insertions(+), 23 deletions(-)
diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c
index 61958a24a43d..acfffdbe9ba1 100644
--- a/drivers/scsi/lpfc/lpfc_init.c
+++ b/drivers/scsi/lpfc/lpfc_init.c
@@ -12473,6 +12473,16 @@ lpfc_hba_eq_hdl_array_init(struct lpfc_hba *phba)
}
}
+static inline int lpfc_next_present_cpu(int n, int first_cpu)
+{
+ n = cpumask_next(n, cpu_present_mask);
+
+ if (n >= nr_cpu_ids)
+ n = first_cpu;
+
+ return n;
+}
+
/**
* lpfc_cpu_affinity_check - Check vector CPU affinity mappings
* @phba: pointer to lpfc hba data structure.
@@ -12561,10 +12571,8 @@ lpfc_cpu_affinity_check(struct lpfc_hba *phba, int vectors)
(new_cpup->eq != LPFC_VECTOR_MAP_EMPTY) &&
(new_cpup->phys_id == cpup->phys_id))
goto found_same;
- new_cpu = cpumask_next(
- new_cpu, cpu_present_mask);
- if (new_cpu == nr_cpumask_bits)
- new_cpu = first_cpu;
+
+ new_cpu = lpfc_next_present_cpu(new_cpu, first_cpu);
}
/* At this point, we leave the CPU as unassigned */
continue;
@@ -12576,9 +12584,7 @@ lpfc_cpu_affinity_check(struct lpfc_hba *phba, int vectors)
* chance of having multiple unassigned CPU entries
* selecting the same IRQ.
*/
- start_cpu = cpumask_next(new_cpu, cpu_present_mask);
- if (start_cpu == nr_cpumask_bits)
- start_cpu = first_cpu;
+ start_cpu = lpfc_next_present_cpu(new_cpu, first_cpu);
lpfc_printf_log(phba, KERN_INFO, LOG_INIT,
"3337 Set Affinity: CPU %d "
@@ -12611,10 +12617,8 @@ lpfc_cpu_affinity_check(struct lpfc_hba *phba, int vectors)
if (!(new_cpup->flag & LPFC_CPU_MAP_UNASSIGN) &&
(new_cpup->eq != LPFC_VECTOR_MAP_EMPTY))
goto found_any;
- new_cpu = cpumask_next(
- new_cpu, cpu_present_mask);
- if (new_cpu == nr_cpumask_bits)
- new_cpu = first_cpu;
+
+ new_cpu = lpfc_next_present_cpu(new_cpu, first_cpu);
}
/* We should never leave an entry unassigned */
lpfc_printf_log(phba, KERN_ERR, LOG_INIT,
@@ -12630,9 +12634,7 @@ lpfc_cpu_affinity_check(struct lpfc_hba *phba, int vectors)
* chance of having multiple unassigned CPU entries
* selecting the same IRQ.
*/
- start_cpu = cpumask_next(new_cpu, cpu_present_mask);
- if (start_cpu == nr_cpumask_bits)
- start_cpu = first_cpu;
+ start_cpu = lpfc_next_present_cpu(new_cpu, first_cpu);
lpfc_printf_log(phba, KERN_INFO, LOG_INIT,
"3338 Set Affinity: CPU %d "
@@ -12703,9 +12705,8 @@ lpfc_cpu_affinity_check(struct lpfc_hba *phba, int vectors)
new_cpup->core_id == cpup->core_id) {
goto found_hdwq;
}
- new_cpu = cpumask_next(new_cpu, cpu_present_mask);
- if (new_cpu == nr_cpumask_bits)
- new_cpu = first_cpu;
+
+ new_cpu = lpfc_next_present_cpu(new_cpu, first_cpu);
}
/* If we can't match both phys_id and core_id,
@@ -12718,9 +12719,7 @@ lpfc_cpu_affinity_check(struct lpfc_hba *phba, int vectors)
new_cpup->phys_id == cpup->phys_id)
goto found_hdwq;
- new_cpu = cpumask_next(new_cpu, cpu_present_mask);
- if (new_cpu == nr_cpumask_bits)
- new_cpu = first_cpu;
+ new_cpu = lpfc_next_present_cpu(new_cpu, first_cpu);
}
/* Otherwise just round robin on cfg_hdw_queue */
@@ -12729,9 +12728,7 @@ lpfc_cpu_affinity_check(struct lpfc_hba *phba, int vectors)
goto logit;
found_hdwq:
/* We found an available entry, copy the IRQ info */
- start_cpu = cpumask_next(new_cpu, cpu_present_mask);
- if (start_cpu == nr_cpumask_bits)
- start_cpu = first_cpu;
+ start_cpu = lpfc_next_present_cpu(new_cpu, first_cpu);
cpup->hdwq = new_cpup->hdwq;
logit:
lpfc_printf_log(phba, KERN_INFO, LOG_INIT,
--
2.34.1
