[OpenPower-Firmware] [PATCH 1/2] scsi: lpfc: Fix oops when fewer hdwqs than cpus
klaus at linux.vnet.ibm.com
klaus at linux.vnet.ibm.com
Tue Oct 22 11:54:38 AEDT 2019
From: James Smart <jsmart2021 at gmail.com>
When tearing down the adapter for a reset, online/offline, or driver
unload, the queue free routine would hit a GPF oops. This only occurs on
conditions where the number of hardware queues created is fewer than the
number of cpus in the system. In this condition cpus share a hardware
queue. And of course, it's the 2nd cpu that shares a hardware that
attempted to free it a second time and hit the oops.
Fix by reworking the cpu to hardware queue mapping such that:
Assignment of hardware queues to cpus occur in two passes:
first pass: is first time assignment of a hardware queue to a cpu.
This will set the LPFC_CPU_FIRST_IRQ flag for the cpu.
second pass: for cpus that did not get a hardware queue they will
be assigned one from a primary cpu (one set in first pass).
Deletion of hardware queues is driven by cpu itteration, and queues
will only be deleted if the LPFC_CPU_FIRST_IRQ flag is set.
Also contains a few small cleanup fixes and a little better logging.
Signed-off-by: Dick Kennedy <dick.kennedy at broadcom.com>
Signed-off-by: James Smart <jsmart2021 at gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen at oracle.com>
---
drivers/scsi/lpfc/lpfc_init.c | 144 +++++++++++++++++++++-------------
1 file changed, 89 insertions(+), 55 deletions(-)
diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c
index 1ac98becb5ba..a5b515fdda2e 100644
--- a/drivers/scsi/lpfc/lpfc_init.c
+++ b/drivers/scsi/lpfc/lpfc_init.c
@@ -8864,7 +8864,7 @@ lpfc_sli4_queue_create(struct lpfc_hba *phba)
}
qdesc->qe_valid = 1;
qdesc->hdwq = cpup->hdwq;
- qdesc->chann = cpu; /* First CPU this EQ is affinitised to */
+ qdesc->chann = cpu; /* First CPU this EQ is affinitized to */
qdesc->last_cpu = qdesc->chann;
/* Save the allocated EQ in the Hardware Queue */
@@ -10711,7 +10711,7 @@ lpfc_find_hyper(struct lpfc_hba *phba, int cpu,
static void
lpfc_cpu_affinity_check(struct lpfc_hba *phba, int vectors)
{
- int i, cpu, idx, new_cpu, start_cpu, first_cpu;
+ int i, cpu, idx, next_idx, new_cpu, start_cpu, first_cpu;
int max_phys_id, min_phys_id;
int max_core_id, min_core_id;
struct lpfc_vector_map_info *cpup;
@@ -10753,8 +10753,8 @@ lpfc_cpu_affinity_check(struct lpfc_hba *phba, int vectors)
#endif
lpfc_printf_log(phba, KERN_INFO, LOG_INIT,
- "3328 CPU physid %d coreid %d\n",
- cpup->phys_id, cpup->core_id);
+ "3328 CPU %d physid %d coreid %d flag x%x\n",
+ cpu, cpup->phys_id, cpup->core_id, cpup->flag);
if (cpup->phys_id > max_phys_id)
max_phys_id = cpup->phys_id;
@@ -10812,17 +10812,17 @@ lpfc_cpu_affinity_check(struct lpfc_hba *phba, int vectors)
cpup->eq = idx;
cpup->irq = pci_irq_vector(phba->pcidev, idx);
- lpfc_printf_log(phba, KERN_INFO, LOG_INIT,
- "3336 Set Affinity: CPU %d "
- "irq %d eq %d\n",
- cpu, cpup->irq, cpup->eq);
-
/* If this is the first CPU thats assigned to this
* vector, set LPFC_CPU_FIRST_IRQ.
*/
if (!i)
cpup->flag |= LPFC_CPU_FIRST_IRQ;
i++;
+
+ lpfc_printf_log(phba, KERN_INFO, LOG_INIT,
+ "3336 Set Affinity: CPU %d "
+ "irq %d eq %d flag x%x\n",
+ cpu, cpup->irq, cpup->eq, cpup->flag);
}
}
@@ -10936,69 +10936,103 @@ lpfc_cpu_affinity_check(struct lpfc_hba *phba, int vectors)
}
}
+ /* Assign hdwq indices that are unique across all cpus in the map
+ * that are also FIRST_CPUs.
+ */
+ idx = 0;
+ for_each_present_cpu(cpu) {
+ cpup = &phba->sli4_hba.cpu_map[cpu];
+
+ /* Only FIRST IRQs get a hdwq index assignment. */
+ if (!(cpup->flag & LPFC_CPU_FIRST_IRQ))
+ continue;
+
+ /* 1 to 1, the first LPFC_CPU_FIRST_IRQ cpus to a unique hdwq */
+ cpup->hdwq = idx;
+ idx++;
+ lpfc_printf_log(phba, KERN_ERR, LOG_INIT,
+ "3333 Set Affinity: CPU %d (phys %d core %d): "
+ "hdwq %d eq %d irq %d flg x%x\n",
+ cpu, cpup->phys_id, cpup->core_id,
+ cpup->hdwq, cpup->eq, cpup->irq, cpup->flag);
+ }
/* Finally we need to associate a hdwq with each cpu_map entry
* This will be 1 to 1 - hdwq to cpu, unless there are less
* hardware queues then CPUs. For that case we will just round-robin
* the available hardware queues as they get assigned to CPUs.
+ * The next_idx is the idx from the FIRST_CPU loop above to account
+ * for irq_chann < hdwq. The idx is used for round-robin assignments
+ * and needs to start at 0.
*/
- idx = 0;
+ next_idx = idx;
start_cpu = 0;
+ idx = 0;
for_each_present_cpu(cpu) {
cpup = &phba->sli4_hba.cpu_map[cpu];
- if (idx >= phba->cfg_hdw_queue) {
- /* We need to reuse a Hardware Queue for another CPU,
- * so be smart about it and pick one that has its
- * IRQ/EQ mapped to the same phys_id (CPU package).
- * and core_id.
- */
- new_cpu = start_cpu;
- for (i = 0; i < phba->sli4_hba.num_present_cpu; i++) {
- new_cpup = &phba->sli4_hba.cpu_map[new_cpu];
- if ((new_cpup->hdwq != LPFC_VECTOR_MAP_EMPTY) &&
- (new_cpup->phys_id == cpup->phys_id) &&
- (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;
- }
- /* If we can't match both phys_id and core_id,
- * settle for just a phys_id match.
- */
- new_cpu = start_cpu;
- for (i = 0; i < phba->sli4_hba.num_present_cpu; i++) {
- new_cpup = &phba->sli4_hba.cpu_map[new_cpu];
- if ((new_cpup->hdwq != LPFC_VECTOR_MAP_EMPTY) &&
- (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;
+ /* FIRST cpus are already mapped. */
+ if (cpup->flag & LPFC_CPU_FIRST_IRQ)
+ continue;
+
+ /* If the cfg_irq_chann < cfg_hdw_queue, set the hdwq
+ * of the unassigned cpus to the next idx so that all
+ * hdw queues are fully utilized.
+ */
+ if (next_idx < phba->cfg_hdw_queue) {
+ cpup->hdwq = next_idx;
+ next_idx++;
+ continue;
+ }
+
+ /* Not a First CPU and all hdw_queues are used. Reuse a
+ * Hardware Queue for another CPU, so be smart about it
+ * and pick one that has its IRQ/EQ mapped to the same phys_id
+ * (CPU package) and core_id.
+ */
+ new_cpu = start_cpu;
+ for (i = 0; i < phba->sli4_hba.num_present_cpu; i++) {
+ new_cpup = &phba->sli4_hba.cpu_map[new_cpu];
+ if (new_cpup->hdwq != LPFC_VECTOR_MAP_EMPTY &&
+ new_cpup->phys_id == cpup->phys_id &&
+ 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;
+ }
- /* Otherwise just round robin on cfg_hdw_queue */
- cpup->hdwq = idx % phba->cfg_hdw_queue;
- 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;
- cpup->hdwq = new_cpup->hdwq;
- } else {
- /* 1 to 1, CPU to hdwq */
- cpup->hdwq = idx;
+ /* If we can't match both phys_id and core_id,
+ * settle for just a phys_id match.
+ */
+ new_cpu = start_cpu;
+ for (i = 0; i < phba->sli4_hba.num_present_cpu; i++) {
+ new_cpup = &phba->sli4_hba.cpu_map[new_cpu];
+ if (new_cpup->hdwq != LPFC_VECTOR_MAP_EMPTY &&
+ 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;
}
-logit:
+
+ /* Otherwise just round robin on cfg_hdw_queue */
+ cpup->hdwq = idx % phba->cfg_hdw_queue;
+ idx++;
+ 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;
+ cpup->hdwq = new_cpup->hdwq;
+ logit:
lpfc_printf_log(phba, KERN_ERR, LOG_INIT,
"3335 Set Affinity: CPU %d (phys %d core %d): "
"hdwq %d eq %d irq %d flg x%x\n",
cpu, cpup->phys_id, cpup->core_id,
cpup->hdwq, cpup->eq, cpup->irq, cpup->flag);
- idx++;
}
/* The cpu_map array will be used later during initialization
--
2.17.1
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