From 6dedcca610c6d6189b4a54d32118d1654adb73d2 Mon Sep 17 00:00:00 2001 From: Toshi Kani Date: Wed, 25 Sep 2013 15:08:27 -0600 Subject: hotplug, powerpc, x86: Remove cpu_hotplug_driver_lock() cpu_hotplug_driver_lock() serializes CPU online/offline operations when ARCH_CPU_PROBE_RELEASE is set. This lock interface is no longer necessary with the following reason: - lock_device_hotplug() now protects CPU online/offline operations, including the probe & release interfaces enabled by ARCH_CPU_PROBE_RELEASE. The use of cpu_hotplug_driver_lock() is redundant. - cpu_hotplug_driver_lock() is only valid when ARCH_CPU_PROBE_RELEASE is defined, which is misleading and is only enabled on powerpc. This patch removes the cpu_hotplug_driver_lock() interface. As a result, ARCH_CPU_PROBE_RELEASE only enables / disables the cpu probe & release interface as intended. There is no functional change in this patch. Signed-off-by: Toshi Kani Reviewed-by: Nathan Fontenot Signed-off-by: Rafael J. Wysocki --- arch/powerpc/kernel/smp.c | 12 ---------- arch/powerpc/platforms/pseries/dlpar.c | 43 +++++++++++++--------------------- 2 files changed, 16 insertions(+), 39 deletions(-) (limited to 'arch/powerpc') diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index 8e59abc..930cd8a 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -844,18 +844,6 @@ void __cpu_die(unsigned int cpu) smp_ops->cpu_die(cpu); } -static DEFINE_MUTEX(powerpc_cpu_hotplug_driver_mutex); - -void cpu_hotplug_driver_lock() -{ - mutex_lock(&powerpc_cpu_hotplug_driver_mutex); -} - -void cpu_hotplug_driver_unlock() -{ - mutex_unlock(&powerpc_cpu_hotplug_driver_mutex); -} - void cpu_die(void) { if (ppc_md.cpu_die) diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c index 7cfdaae..a8fe5aa 100644 --- a/arch/powerpc/platforms/pseries/dlpar.c +++ b/arch/powerpc/platforms/pseries/dlpar.c @@ -404,46 +404,38 @@ static ssize_t dlpar_cpu_probe(const char *buf, size_t count) unsigned long drc_index; int rc; - cpu_hotplug_driver_lock(); rc = strict_strtoul(buf, 0, &drc_index); - if (rc) { - rc = -EINVAL; - goto out; - } + if (rc) + return -EINVAL; parent = of_find_node_by_path("/cpus"); - if (!parent) { - rc = -ENODEV; - goto out; - } + if (!parent) + return -ENODEV; dn = dlpar_configure_connector(drc_index, parent); - if (!dn) { - rc = -EINVAL; - goto out; - } + if (!dn) + return -EINVAL; of_node_put(parent); rc = dlpar_acquire_drc(drc_index); if (rc) { dlpar_free_cc_nodes(dn); - rc = -EINVAL; - goto out; + return -EINVAL; } rc = dlpar_attach_node(dn); if (rc) { dlpar_release_drc(drc_index); dlpar_free_cc_nodes(dn); - goto out; + return rc; } rc = dlpar_online_cpu(dn); -out: - cpu_hotplug_driver_unlock(); + if (rc) + return rc; - return rc ? rc : count; + return count; } static int dlpar_offline_cpu(struct device_node *dn) @@ -516,30 +508,27 @@ static ssize_t dlpar_cpu_release(const char *buf, size_t count) return -EINVAL; } - cpu_hotplug_driver_lock(); rc = dlpar_offline_cpu(dn); if (rc) { of_node_put(dn); - rc = -EINVAL; - goto out; + return -EINVAL; } rc = dlpar_release_drc(*drc_index); if (rc) { of_node_put(dn); - goto out; + return rc; } rc = dlpar_detach_node(dn); if (rc) { dlpar_acquire_drc(*drc_index); - goto out; + return rc; } of_node_put(dn); -out: - cpu_hotplug_driver_unlock(); - return rc ? rc : count; + + return count; } static int __init pseries_dlpar_init(void) -- cgit v1.1