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authorLinus Torvalds <torvalds@linux-foundation.org>2016-01-16 00:18:47 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2016-01-16 00:18:47 +0300
commitf689b742f217b2ffe7925f8a6521b208ee995309 (patch)
tree40ed4482ce5808fd5498fe935205b06782bbbca4 /arch/powerpc/platforms/pseries/hotplug-cpu.c
parent37cea93b99d2d89bef3adcb4632d71e1f377c447 (diff)
parentbe6bfc29bc759670fb3a2519325c4ab2edf259c9 (diff)
downloadlinux-f689b742f217b2ffe7925f8a6521b208ee995309.tar.xz
Merge tag 'powerpc-4.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman: "Core: - Ground work for the new Power9 MMU from Aneesh Kumar K.V - Optimise FP/VMX/VSX context switching from Anton Blanchard Misc: - Various cleanups from Krzysztof Kozlowski, John Ogness, Rashmica Gupta, Russell Currey, Gavin Shan, Daniel Axtens, Michael Neuling, Andrew Donnellan - Allow wrapper to work on non-english system from Laurent Vivier - Add rN aliases to the pt_regs_offset table from Rashmica Gupta - Fix module autoload for rackmeter & axonram drivers from Luis de Bethencourt - Include KVM guest test in all interrupt vectors from Paul Mackerras - Fix DSCR inheritance over fork() from Anton Blanchard - Make value-returning atomics & {cmp}xchg* & their atomic_ versions fully ordered from Boqun Feng - Print MSR TM bits in oops messages from Michael Neuling - Add TM signal return & invalid stack selftests from Michael Neuling - Limit EPOW reset event warnings from Vipin K Parashar - Remove the Cell QPACE code from Rashmica Gupta - Append linux_banner to exception information in xmon from Rashmica Gupta - Add selftest to check if VSRs are corrupted from Rashmica Gupta - Remove broken GregorianDay() from Daniel Axtens - Import Anton's context_switch2 benchmark into selftests from Michael Ellerman - Add selftest script to test HMI functionality from Daniel Axtens - Remove obsolete OPAL v2 support from Stewart Smith - Make enter_rtas() private from Michael Ellerman - PPR exception cleanups from Michael Ellerman - Add page soft dirty tracking from Laurent Dufour - Add support for Nvlink NPUs from Alistair Popple - Add support for kexec on 476fpe from Alistair Popple - Enable kernel CPU dlpar from sysfs from Nathan Fontenot - Copy only required pieces of the mm_context_t to the paca from Michael Neuling - Add a kmsg_dumper that flushes OPAL console output on panic from Russell Currey - Implement save_stack_trace_regs() to enable kprobe stack tracing from Steven Rostedt - Add HWCAP bits for Power9 from Michael Ellerman - Fix _PAGE_PTE breaking swapoff from Aneesh Kumar K.V - Fix _PAGE_SWP_SOFT_DIRTY breaking swapoff from Hugh Dickins - scripts/recordmcount.pl: support data in text section on powerpc from Ulrich Weigand - Handle R_PPC64_ENTRY relocations in modules from Ulrich Weigand cxl: - cxl: Fix possible idr warning when contexts are released from Vaibhav Jain - cxl: use correct operator when writing pcie config space values from Andrew Donnellan - cxl: Fix DSI misses when the context owning task exits from Vaibhav Jain - cxl: fix build for GCC 4.6.x from Brian Norris - cxl: use -Werror only with CONFIG_PPC_WERROR from Brian Norris - cxl: Enable PCI device ID for future IBM CXL adapter from Uma Krishnan Freescale: - Freescale updates from Scott: Highlights include moving QE code out of arch/powerpc (to be shared with arm), device tree updates, and minor fixes" * tag 'powerpc-4.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (149 commits) powerpc/module: Handle R_PPC64_ENTRY relocations scripts/recordmcount.pl: support data in text section on powerpc powerpc/powernv: Fix OPAL_CONSOLE_FLUSH prototype and usages powerpc/mm: fix _PAGE_SWP_SOFT_DIRTY breaking swapoff powerpc/mm: Fix _PAGE_PTE breaking swapoff cxl: Enable PCI device ID for future IBM CXL adapter cxl: use -Werror only with CONFIG_PPC_WERROR cxl: fix build for GCC 4.6.x powerpc: Add HWCAP bits for Power9 powerpc/powernv: Reserve PE#0 on NPU powerpc/powernv: Change NPU PE# assignment powerpc/powernv: Fix update of NVLink DMA mask powerpc/powernv: Remove misleading comment in pci.c powerpc: Implement save_stack_trace_regs() to enable kprobe stack tracing powerpc: Fix build break due to paca mm_context_t changes cxl: Fix DSI misses when the context owning task exits MAINTAINERS: Update Scott Wood's e-mail address powerpc/powernv: Fix minor off-by-one error in opal_mce_check_early_recovery() powerpc: Fix style of self-test config prompts powerpc/powernv: Only delay opal_rtc_read() retry when necessary ...
Diffstat (limited to 'arch/powerpc/platforms/pseries/hotplug-cpu.c')
-rw-r--r--arch/powerpc/platforms/pseries/hotplug-cpu.c550
1 files changed, 542 insertions, 8 deletions
diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c
index 62475440fd45..32274f72fe3f 100644
--- a/arch/powerpc/platforms/pseries/hotplug-cpu.c
+++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c
@@ -18,12 +18,15 @@
* 2 of the License, or (at your option) any later version.
*/
+#define pr_fmt(fmt) "pseries-hotplug-cpu: " fmt
+
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/sched.h> /* for idle_task_exit */
#include <linux/cpu.h>
#include <linux/of.h>
+#include <linux/slab.h>
#include <asm/prom.h>
#include <asm/rtas.h>
#include <asm/firmware.h>
@@ -32,6 +35,7 @@
#include <asm/xics.h>
#include <asm/plpar_wrappers.h>
+#include "pseries.h"
#include "offline_states.h"
/* This version can't take the spinlock, because it never returns */
@@ -88,13 +92,7 @@ void set_default_offline_state(int cpu)
static void rtas_stop_self(void)
{
- static struct rtas_args args = {
- .nargs = 0,
- .nret = cpu_to_be32(1),
- .rets = &args.args[0],
- };
-
- args.token = cpu_to_be32(rtas_stop_self_token);
+ static struct rtas_args args;
local_irq_disable();
@@ -102,7 +100,8 @@ static void rtas_stop_self(void)
printk("cpu %u (hwid %u) Ready to die...\n",
smp_processor_id(), hard_smp_processor_id());
- enter_rtas(__pa(&args));
+
+ rtas_call_unlocked(&args, rtas_stop_self_token, 0, 1, NULL);
panic("Alas, I survived.\n");
}
@@ -339,6 +338,536 @@ static void pseries_remove_processor(struct device_node *np)
cpu_maps_update_done();
}
+static int dlpar_online_cpu(struct device_node *dn)
+{
+ int rc = 0;
+ unsigned int cpu;
+ int len, nthreads, i;
+ const __be32 *intserv;
+ u32 thread;
+
+ intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s", &len);
+ if (!intserv)
+ return -EINVAL;
+
+ nthreads = len / sizeof(u32);
+
+ cpu_maps_update_begin();
+ for (i = 0; i < nthreads; i++) {
+ thread = be32_to_cpu(intserv[i]);
+ for_each_present_cpu(cpu) {
+ if (get_hard_smp_processor_id(cpu) != thread)
+ continue;
+ BUG_ON(get_cpu_current_state(cpu)
+ != CPU_STATE_OFFLINE);
+ cpu_maps_update_done();
+ rc = device_online(get_cpu_device(cpu));
+ if (rc)
+ goto out;
+ cpu_maps_update_begin();
+
+ break;
+ }
+ if (cpu == num_possible_cpus())
+ printk(KERN_WARNING "Could not find cpu to online "
+ "with physical id 0x%x\n", thread);
+ }
+ cpu_maps_update_done();
+
+out:
+ return rc;
+
+}
+
+static bool dlpar_cpu_exists(struct device_node *parent, u32 drc_index)
+{
+ struct device_node *child = NULL;
+ u32 my_drc_index;
+ bool found;
+ int rc;
+
+ /* Assume cpu doesn't exist */
+ found = false;
+
+ for_each_child_of_node(parent, child) {
+ rc = of_property_read_u32(child, "ibm,my-drc-index",
+ &my_drc_index);
+ if (rc)
+ continue;
+
+ if (my_drc_index == drc_index) {
+ of_node_put(child);
+ found = true;
+ break;
+ }
+ }
+
+ return found;
+}
+
+static bool valid_cpu_drc_index(struct device_node *parent, u32 drc_index)
+{
+ bool found = false;
+ int rc, index;
+
+ index = 0;
+ while (!found) {
+ u32 drc;
+
+ rc = of_property_read_u32_index(parent, "ibm,drc-indexes",
+ index++, &drc);
+ if (rc)
+ break;
+
+ if (drc == drc_index)
+ found = true;
+ }
+
+ return found;
+}
+
+static ssize_t dlpar_cpu_add(u32 drc_index)
+{
+ struct device_node *dn, *parent;
+ int rc, saved_rc;
+
+ pr_debug("Attempting to add CPU, drc index: %x\n", drc_index);
+
+ parent = of_find_node_by_path("/cpus");
+ if (!parent) {
+ pr_warn("Failed to find CPU root node \"/cpus\"\n");
+ return -ENODEV;
+ }
+
+ if (dlpar_cpu_exists(parent, drc_index)) {
+ of_node_put(parent);
+ pr_warn("CPU with drc index %x already exists\n", drc_index);
+ return -EINVAL;
+ }
+
+ if (!valid_cpu_drc_index(parent, drc_index)) {
+ of_node_put(parent);
+ pr_warn("Cannot find CPU (drc index %x) to add.\n", 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;
+ }
+
+ dn = dlpar_configure_connector(cpu_to_be32(drc_index), parent);
+ of_node_put(parent);
+ if (!dn) {
+ pr_warn("Failed call to configure-connector, drc index: %x\n",
+ drc_index);
+ dlpar_release_drc(drc_index);
+ return -EINVAL;
+ }
+
+ rc = dlpar_attach_node(dn);
+ if (rc) {
+ saved_rc = rc;
+ 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);
+
+ return saved_rc;
+ }
+
+ rc = dlpar_online_cpu(dn);
+ if (rc) {
+ saved_rc = rc;
+ pr_warn("Failed to online cpu %s, rc: %d, drc index: %x\n",
+ dn->name, rc, drc_index);
+
+ rc = dlpar_detach_node(dn);
+ if (!rc)
+ dlpar_release_drc(drc_index);
+
+ return saved_rc;
+ }
+
+ pr_debug("Successfully added CPU %s, drc index: %x\n", dn->name,
+ drc_index);
+ return rc;
+}
+
+static int dlpar_offline_cpu(struct device_node *dn)
+{
+ int rc = 0;
+ unsigned int cpu;
+ int len, nthreads, i;
+ const __be32 *intserv;
+ u32 thread;
+
+ intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s", &len);
+ if (!intserv)
+ return -EINVAL;
+
+ nthreads = len / sizeof(u32);
+
+ cpu_maps_update_begin();
+ for (i = 0; i < nthreads; i++) {
+ thread = be32_to_cpu(intserv[i]);
+ for_each_present_cpu(cpu) {
+ if (get_hard_smp_processor_id(cpu) != thread)
+ continue;
+
+ if (get_cpu_current_state(cpu) == CPU_STATE_OFFLINE)
+ break;
+
+ if (get_cpu_current_state(cpu) == CPU_STATE_ONLINE) {
+ set_preferred_offline_state(cpu,
+ CPU_STATE_OFFLINE);
+ cpu_maps_update_done();
+ rc = device_offline(get_cpu_device(cpu));
+ if (rc)
+ goto out;
+ cpu_maps_update_begin();
+ break;
+
+ }
+
+ /*
+ * The cpu is in CPU_STATE_INACTIVE.
+ * Upgrade it's state to CPU_STATE_OFFLINE.
+ */
+ set_preferred_offline_state(cpu, CPU_STATE_OFFLINE);
+ BUG_ON(plpar_hcall_norets(H_PROD, thread)
+ != H_SUCCESS);
+ __cpu_die(cpu);
+ break;
+ }
+ if (cpu == num_possible_cpus())
+ printk(KERN_WARNING "Could not find cpu to offline with physical id 0x%x\n", thread);
+ }
+ cpu_maps_update_done();
+
+out:
+ return rc;
+
+}
+
+static ssize_t dlpar_cpu_remove(struct device_node *dn, u32 drc_index)
+{
+ int rc;
+
+ pr_debug("Attemping to remove CPU %s, drc index: %x\n",
+ dn->name, drc_index);
+
+ rc = dlpar_offline_cpu(dn);
+ if (rc) {
+ pr_warn("Failed to offline CPU %s, rc: %d\n", dn->name, rc);
+ 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;
+ }
+
+ rc = dlpar_detach_node(dn);
+ if (rc) {
+ int saved_rc = rc;
+
+ pr_warn("Failed to detach CPU %s, rc: %d", dn->name, rc);
+
+ rc = dlpar_acquire_drc(drc_index);
+ if (!rc)
+ dlpar_online_cpu(dn);
+
+ return saved_rc;
+ }
+
+ pr_debug("Successfully removed CPU, drc index: %x\n", drc_index);
+ return 0;
+}
+
+static struct device_node *cpu_drc_index_to_dn(u32 drc_index)
+{
+ struct device_node *dn;
+ u32 my_index;
+ int rc;
+
+ for_each_node_by_type(dn, "cpu") {
+ rc = of_property_read_u32(dn, "ibm,my-drc-index", &my_index);
+ if (rc)
+ continue;
+
+ if (my_index == drc_index)
+ break;
+ }
+
+ return dn;
+}
+
+static int dlpar_cpu_remove_by_index(u32 drc_index)
+{
+ struct device_node *dn;
+ int rc;
+
+ dn = cpu_drc_index_to_dn(drc_index);
+ if (!dn) {
+ pr_warn("Cannot find CPU (drc index %x) to remove\n",
+ drc_index);
+ return -ENODEV;
+ }
+
+ rc = dlpar_cpu_remove(dn, drc_index);
+ of_node_put(dn);
+ return rc;
+}
+
+static int find_dlpar_cpus_to_remove(u32 *cpu_drcs, int cpus_to_remove)
+{
+ struct device_node *dn;
+ int cpus_found = 0;
+ int rc;
+
+ /* We want to find cpus_to_remove + 1 CPUs to ensure we do not
+ * remove the last CPU.
+ */
+ for_each_node_by_type(dn, "cpu") {
+ cpus_found++;
+
+ if (cpus_found > cpus_to_remove) {
+ of_node_put(dn);
+ break;
+ }
+
+ /* Note that cpus_found is always 1 ahead of the index
+ * into the cpu_drcs array, so we use cpus_found - 1
+ */
+ rc = of_property_read_u32(dn, "ibm,my-drc-index",
+ &cpu_drcs[cpus_found - 1]);
+ if (rc) {
+ pr_warn("Error occurred getting drc-index for %s\n",
+ dn->name);
+ of_node_put(dn);
+ return -1;
+ }
+ }
+
+ if (cpus_found < cpus_to_remove) {
+ pr_warn("Failed to find enough CPUs (%d of %d) to remove\n",
+ cpus_found, cpus_to_remove);
+ } else if (cpus_found == cpus_to_remove) {
+ pr_warn("Cannot remove all CPUs\n");
+ }
+
+ return cpus_found;
+}
+
+static int dlpar_cpu_remove_by_count(u32 cpus_to_remove)
+{
+ u32 *cpu_drcs;
+ int cpus_found;
+ int cpus_removed = 0;
+ int i, rc;
+
+ pr_debug("Attempting to hot-remove %d CPUs\n", cpus_to_remove);
+
+ cpu_drcs = kcalloc(cpus_to_remove, sizeof(*cpu_drcs), GFP_KERNEL);
+ if (!cpu_drcs)
+ return -EINVAL;
+
+ cpus_found = find_dlpar_cpus_to_remove(cpu_drcs, cpus_to_remove);
+ if (cpus_found <= cpus_to_remove) {
+ kfree(cpu_drcs);
+ return -EINVAL;
+ }
+
+ for (i = 0; i < cpus_to_remove; i++) {
+ rc = dlpar_cpu_remove_by_index(cpu_drcs[i]);
+ if (rc)
+ break;
+
+ cpus_removed++;
+ }
+
+ if (cpus_removed != 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]);
+
+ rc = -EINVAL;
+ } else {
+ rc = 0;
+ }
+
+ kfree(cpu_drcs);
+ return rc;
+}
+
+static int find_dlpar_cpus_to_add(u32 *cpu_drcs, u32 cpus_to_add)
+{
+ struct device_node *parent;
+ int cpus_found = 0;
+ int index, rc;
+
+ parent = of_find_node_by_path("/cpus");
+ if (!parent) {
+ pr_warn("Could not find CPU root node in device tree\n");
+ kfree(cpu_drcs);
+ return -1;
+ }
+
+ /* Search the ibm,drc-indexes array for possible CPU drcs to
+ * add. Note that the format of the ibm,drc-indexes array is
+ * the number of entries in the array followed by the array
+ * of drc values so we start looking at index = 1.
+ */
+ index = 1;
+ while (cpus_found < cpus_to_add) {
+ u32 drc;
+
+ rc = of_property_read_u32_index(parent, "ibm,drc-indexes",
+ index++, &drc);
+ if (rc)
+ break;
+
+ if (dlpar_cpu_exists(parent, drc))
+ continue;
+
+ cpu_drcs[cpus_found++] = drc;
+ }
+
+ of_node_put(parent);
+ return cpus_found;
+}
+
+static int dlpar_cpu_add_by_count(u32 cpus_to_add)
+{
+ u32 *cpu_drcs;
+ int cpus_added = 0;
+ int cpus_found;
+ int i, rc;
+
+ pr_debug("Attempting to hot-add %d CPUs\n", cpus_to_add);
+
+ cpu_drcs = kcalloc(cpus_to_add, sizeof(*cpu_drcs), GFP_KERNEL);
+ if (!cpu_drcs)
+ return -EINVAL;
+
+ cpus_found = find_dlpar_cpus_to_add(cpu_drcs, cpus_to_add);
+ if (cpus_found < cpus_to_add) {
+ pr_warn("Failed to find enough CPUs (%d of %d) to add\n",
+ cpus_found, cpus_to_add);
+ kfree(cpu_drcs);
+ return -EINVAL;
+ }
+
+ for (i = 0; i < cpus_to_add; i++) {
+ rc = dlpar_cpu_add(cpu_drcs[i]);
+ if (rc)
+ break;
+
+ cpus_added++;
+ }
+
+ if (cpus_added < 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]);
+
+ rc = -EINVAL;
+ } else {
+ rc = 0;
+ }
+
+ kfree(cpu_drcs);
+ return rc;
+}
+
+int dlpar_cpu(struct pseries_hp_errorlog *hp_elog)
+{
+ u32 count, drc_index;
+ int rc;
+
+ count = hp_elog->_drc_u.drc_count;
+ drc_index = hp_elog->_drc_u.drc_index;
+
+ lock_device_hotplug();
+
+ switch (hp_elog->action) {
+ case PSERIES_HP_ELOG_ACTION_REMOVE:
+ 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);
+ else
+ rc = -EINVAL;
+ break;
+ case PSERIES_HP_ELOG_ACTION_ADD:
+ 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);
+ else
+ rc = -EINVAL;
+ break;
+ default:
+ pr_err("Invalid action (%d) specified\n", hp_elog->action);
+ rc = -EINVAL;
+ break;
+ }
+
+ unlock_device_hotplug();
+ return rc;
+}
+
+#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
+
+static ssize_t dlpar_cpu_probe(const char *buf, size_t count)
+{
+ u32 drc_index;
+ int rc;
+
+ rc = kstrtou32(buf, 0, &drc_index);
+ if (rc)
+ return -EINVAL;
+
+ rc = dlpar_cpu_add(drc_index);
+
+ return rc ? rc : count;
+}
+
+static ssize_t dlpar_cpu_release(const char *buf, size_t count)
+{
+ struct device_node *dn;
+ u32 drc_index;
+ int rc;
+
+ dn = of_find_node_by_path(buf);
+ if (!dn)
+ return -EINVAL;
+
+ rc = of_property_read_u32(dn, "ibm,my-drc-index", &drc_index);
+ if (rc) {
+ of_node_put(dn);
+ return -EINVAL;
+ }
+
+ rc = dlpar_cpu_remove(dn, drc_index);
+ of_node_put(dn);
+
+ return rc ? rc : count;
+}
+
+#endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */
+
static int pseries_smp_notifier(struct notifier_block *nb,
unsigned long action, void *data)
{
@@ -385,6 +914,11 @@ static int __init pseries_cpu_hotplug_init(void)
int cpu;
int qcss_tok;
+#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
+ ppc_md.cpu_probe = dlpar_cpu_probe;
+ ppc_md.cpu_release = dlpar_cpu_release;
+#endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */
+
for_each_node_by_name(np, "interrupt-controller") {
typep = of_get_property(np, "compatible", NULL);
if (strstr(typep, "open-pic")) {