From ec2087a725f42bfbe239120768933e881aab73cd Mon Sep 17 00:00:00 2001 From: James Smart Date: Fri, 6 Sep 2013 12:20:36 -0400 Subject: [PATCH] [SCSI] lpfc 8.3.42: Fix crash on driver load due to cpu affinity logic Signed-off-by: James Smart Signed-off-by: James Bottomley --- drivers/scsi/lpfc/lpfc_attr.c | 5 ++++- drivers/scsi/lpfc/lpfc_init.c | 28 +++++++++++++++++++++++----- 2 files changed, 27 insertions(+), 6 deletions(-) diff --git a/drivers/scsi/lpfc/lpfc_attr.c b/drivers/scsi/lpfc/lpfc_attr.c index 18b3a1d7f3f0..ad80f9ca2dbb 100644 --- a/drivers/scsi/lpfc/lpfc_attr.c +++ b/drivers/scsi/lpfc/lpfc_attr.c @@ -4013,8 +4013,11 @@ LPFC_ATTR_R(ack0, 0, 0, 1, "Enable ACK0 support"); # For [0], FCP commands are issued to Work Queues ina round robin fashion. # For [1], FCP commands are issued to a Work Queue associated with the # current CPU. +# It would be set to 1 by the driver if it's able to set up cpu affinity +# for FCP I/Os through Work Queue associated with the current CPU. Otherwise, +# roundrobin scheduling of FCP I/Os through WQs will be used. */ -LPFC_ATTR_RW(fcp_io_sched, 0, 0, 1, "Determine scheduling algrithmn for " +LPFC_ATTR_RW(fcp_io_sched, 0, 0, 1, "Determine scheduling algorithm for " "issuing commands [0] - Round Robin, [1] - Current CPU"); /* diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c index b94420b3817a..b0a500be8b1f 100644 --- a/drivers/scsi/lpfc/lpfc_init.c +++ b/drivers/scsi/lpfc/lpfc_init.c @@ -8399,7 +8399,8 @@ static int lpfc_sli4_set_affinity(struct lpfc_hba *phba, int vectors) { int i, idx, saved_chann, used_chann, cpu, phys_id; - int max_phys_id, num_io_channel, first_cpu; + int max_phys_id, min_phys_id; + int num_io_channel, first_cpu, chan; struct lpfc_vector_map_info *cpup; #ifdef CONFIG_X86 struct cpuinfo_x86 *cpuinfo; @@ -8417,6 +8418,7 @@ lpfc_sli4_set_affinity(struct lpfc_hba *phba, int vectors) phba->sli4_hba.num_present_cpu)); max_phys_id = 0; + min_phys_id = 0xff; phys_id = 0; num_io_channel = 0; first_cpu = LPFC_VECTOR_MAP_EMPTY; @@ -8440,9 +8442,12 @@ lpfc_sli4_set_affinity(struct lpfc_hba *phba, int vectors) if (cpup->phys_id > max_phys_id) max_phys_id = cpup->phys_id; + if (cpup->phys_id < min_phys_id) + min_phys_id = cpup->phys_id; cpup++; } + phys_id = min_phys_id; /* Now associate the HBA vectors with specific CPUs */ for (idx = 0; idx < vectors; idx++) { cpup = phba->sli4_hba.cpu_map; @@ -8453,13 +8458,25 @@ lpfc_sli4_set_affinity(struct lpfc_hba *phba, int vectors) for (i = 1; i < max_phys_id; i++) { phys_id++; if (phys_id > max_phys_id) - phys_id = 0; + phys_id = min_phys_id; cpu = lpfc_find_next_cpu(phba, phys_id); if (cpu == LPFC_VECTOR_MAP_EMPTY) continue; goto found; } + /* Use round robin for scheduling */ + phba->cfg_fcp_io_sched = LPFC_FCP_SCHED_ROUND_ROBIN; + chan = 0; + cpup = phba->sli4_hba.cpu_map; + for (i = 0; i < phba->sli4_hba.num_present_cpu; i++) { + cpup->channel_id = chan; + cpup++; + chan++; + if (chan >= phba->cfg_fcp_io_channel) + chan = 0; + } + lpfc_printf_log(phba, KERN_ERR, LOG_INIT, "3329 Cannot set affinity:" "Error mapping vector %d (%d)\n", @@ -8497,7 +8514,7 @@ found: /* Spread vector mapping across multple physical CPU nodes */ phys_id++; if (phys_id > max_phys_id) - phys_id = 0; + phys_id = min_phys_id; } /* @@ -8507,7 +8524,7 @@ found: * Base the remaining IO channel assigned, to IO channels already * assigned to other CPUs on the same phys_id. */ - for (i = 0; i <= max_phys_id; i++) { + for (i = min_phys_id; i <= max_phys_id; i++) { /* * If there are no io channels already mapped to * this phys_id, just round robin thru the io_channels. @@ -8589,10 +8606,11 @@ out: if (num_io_channel != phba->sli4_hba.num_present_cpu) lpfc_printf_log(phba, KERN_ERR, LOG_INIT, "3333 Set affinity mismatch:" - "%d chann != %d cpus: %d vactors\n", + "%d chann != %d cpus: %d vectors\n", num_io_channel, phba->sli4_hba.num_present_cpu, vectors); + /* Enable using cpu affinity for scheduling */ phba->cfg_fcp_io_sched = LPFC_FCP_SCHED_BY_CPU; return 1; }