powerpc/cpu: Modify dlpar_cpu_add and dlpar_cpu_remove to allow the skipping of DRC index acquire or release operations during the CPU add or remove operations. This is intended to support subsequent changes to provide a 'CPU readd' operation.
Signed-off-by: Michael Bringmann <m...@linux.vnet.ibm.com> --- Changes in patch: -- Move new validity check added to pseries_smp_notifier to another patch -- Revise one of checks for 'acquire_drc' in dlpar_cpu_add. -- Revise one of checks for 'release_drc' in dlpar_cpu_remove. --- arch/powerpc/platforms/pseries/hotplug-cpu.c | 71 +++++++++++++++----------- 1 file changed, 40 insertions(+), 31 deletions(-) diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c index 6ef77ca..7ede3b0 100644 --- a/arch/powerpc/platforms/pseries/hotplug-cpu.c +++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c @@ -432,7 +432,7 @@ static bool valid_cpu_drc_index(struct device_node *parent, u32 drc_index) return found; } -static ssize_t dlpar_cpu_add(u32 drc_index) +static ssize_t dlpar_cpu_add(u32 drc_index, bool acquire_drc) { struct device_node *dn, *parent; int rc, saved_rc; @@ -457,19 +457,22 @@ static ssize_t dlpar_cpu_add(u32 drc_index) return -EINVAL; } - rc = dlpar_acquire_drc(drc_index); - if (rc) { - pr_warn("Failed to acquire DRC, rc: %d, drc index: %x\n", - rc, drc_index); - of_node_put(parent); - return -EINVAL; + if (acquire_drc) { + rc = dlpar_acquire_drc(drc_index); + if (rc) { + pr_warn("Failed to acquire DRC, rc: %d, drc index: %x\n", + rc, drc_index); + of_node_put(parent); + return -EINVAL; + } } dn = dlpar_configure_connector(cpu_to_be32(drc_index), parent); if (!dn) { pr_warn("Failed call to configure-connector, drc index: %x\n", drc_index); - dlpar_release_drc(drc_index); + if (acquire_drc) + dlpar_release_drc(drc_index); of_node_put(parent); return -EINVAL; } @@ -484,9 +487,11 @@ static ssize_t dlpar_cpu_add(u32 drc_index) pr_warn("Failed to attach node %s, rc: %d, drc index: %x\n", dn->name, rc, drc_index); - rc = dlpar_release_drc(drc_index); - if (!rc) - dlpar_free_cc_nodes(dn); + if (acquire_drc) { + rc = dlpar_release_drc(drc_index); + if (!rc) + dlpar_free_cc_nodes(dn); + } return saved_rc; } @@ -498,7 +503,7 @@ static ssize_t dlpar_cpu_add(u32 drc_index) dn->name, rc, drc_index); rc = dlpar_detach_node(dn); - if (!rc) + if (!rc && acquire_drc) dlpar_release_drc(drc_index); return saved_rc; @@ -566,7 +571,8 @@ static int dlpar_offline_cpu(struct device_node *dn) } -static ssize_t dlpar_cpu_remove(struct device_node *dn, u32 drc_index) +static ssize_t dlpar_cpu_remove(struct device_node *dn, u32 drc_index, + bool release_drc) { int rc; @@ -579,12 +585,14 @@ static ssize_t dlpar_cpu_remove(struct device_node *dn, u32 drc_index) return -EINVAL; } - rc = dlpar_release_drc(drc_index); - if (rc) { - pr_warn("Failed to release drc (%x) for CPU %s, rc: %d\n", - drc_index, dn->name, rc); - dlpar_online_cpu(dn); - return rc; + if (release_drc) { + rc = dlpar_release_drc(drc_index); + if (rc) { + pr_warn("Failed to release drc (%x) for CPU %s, rc: %d\n", + drc_index, dn->name, rc); + dlpar_online_cpu(dn); + return rc; + } } rc = dlpar_detach_node(dn); @@ -593,8 +601,9 @@ static ssize_t dlpar_cpu_remove(struct device_node *dn, u32 drc_index) pr_warn("Failed to detach CPU %s, rc: %d", dn->name, rc); - rc = dlpar_acquire_drc(drc_index); - if (!rc) + if (release_drc) + rc = dlpar_acquire_drc(drc_index); + if (!release_drc || !rc) dlpar_online_cpu(dn); return saved_rc; @@ -622,7 +631,7 @@ static struct device_node *cpu_drc_index_to_dn(u32 drc_index) return dn; } -static int dlpar_cpu_remove_by_index(u32 drc_index) +static int dlpar_cpu_remove_by_index(u32 drc_index, bool release_drc) { struct device_node *dn; int rc; @@ -634,7 +643,7 @@ static int dlpar_cpu_remove_by_index(u32 drc_index) return -ENODEV; } - rc = dlpar_cpu_remove(dn, drc_index); + rc = dlpar_cpu_remove(dn, drc_index, release_drc); of_node_put(dn); return rc; } @@ -699,7 +708,7 @@ static int dlpar_cpu_remove_by_count(u32 cpus_to_remove) } for (i = 0; i < cpus_to_remove; i++) { - rc = dlpar_cpu_remove_by_index(cpu_drcs[i]); + rc = dlpar_cpu_remove_by_index(cpu_drcs[i], true); if (rc) break; @@ -710,7 +719,7 @@ static int dlpar_cpu_remove_by_count(u32 cpus_to_remove) pr_warn("CPU hot-remove failed, adding back removed CPUs\n"); for (i = 0; i < cpus_removed; i++) - dlpar_cpu_add(cpu_drcs[i]); + dlpar_cpu_add(cpu_drcs[i], true); rc = -EINVAL; } else { @@ -780,7 +789,7 @@ static int dlpar_cpu_add_by_count(u32 cpus_to_add) } for (i = 0; i < cpus_to_add; i++) { - rc = dlpar_cpu_add(cpu_drcs[i]); + rc = dlpar_cpu_add(cpu_drcs[i], true); if (rc) break; @@ -791,7 +800,7 @@ static int dlpar_cpu_add_by_count(u32 cpus_to_add) pr_warn("CPU hot-add failed, removing any added CPUs\n"); for (i = 0; i < cpus_added; i++) - dlpar_cpu_remove_by_index(cpu_drcs[i]); + dlpar_cpu_remove_by_index(cpu_drcs[i], true); rc = -EINVAL; } else { @@ -817,7 +826,7 @@ int dlpar_cpu(struct pseries_hp_errorlog *hp_elog) if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT) rc = dlpar_cpu_remove_by_count(count); else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX) - rc = dlpar_cpu_remove_by_index(drc_index); + rc = dlpar_cpu_remove_by_index(drc_index, true); else rc = -EINVAL; break; @@ -825,7 +834,7 @@ int dlpar_cpu(struct pseries_hp_errorlog *hp_elog) if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT) rc = dlpar_cpu_add_by_count(count); else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX) - rc = dlpar_cpu_add(drc_index); + rc = dlpar_cpu_add(drc_index, true); else rc = -EINVAL; break; @@ -850,7 +859,7 @@ static ssize_t dlpar_cpu_probe(const char *buf, size_t count) if (rc) return -EINVAL; - rc = dlpar_cpu_add(drc_index); + rc = dlpar_cpu_add(drc_index, true); return rc ? rc : count; } @@ -871,7 +880,7 @@ static ssize_t dlpar_cpu_release(const char *buf, size_t count) return -EINVAL; } - rc = dlpar_cpu_remove(dn, drc_index); + rc = dlpar_cpu_remove(dn, drc_index, true); of_node_put(dn); return rc ? rc : count;