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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/s390/oprofile
Initial import
Diffstat (limited to 'arch/s390/oprofile')
-rw-r--r--arch/s390/oprofile/Makefile10
-rw-r--r--arch/s390/oprofile/backtrace.c77
-rw-r--r--arch/s390/oprofile/hwsampler.c1178
-rw-r--r--arch/s390/oprofile/hwsampler.h63
-rw-r--r--arch/s390/oprofile/init.c513
-rw-r--r--arch/s390/oprofile/op_counter.h21
6 files changed, 1862 insertions, 0 deletions
diff --git a/arch/s390/oprofile/Makefile b/arch/s390/oprofile/Makefile
new file mode 100644
index 000000000..1bd230171
--- /dev/null
+++ b/arch/s390/oprofile/Makefile
@@ -0,0 +1,10 @@
+obj-$(CONFIG_OPROFILE) += oprofile.o
+
+DRIVER_OBJS = $(addprefix ../../../drivers/oprofile/, \
+ oprof.o cpu_buffer.o buffer_sync.o \
+ event_buffer.o oprofile_files.o \
+ oprofilefs.o oprofile_stats.o \
+ timer_int.o )
+
+oprofile-y := $(DRIVER_OBJS) init.o backtrace.o
+oprofile-y += hwsampler.o
diff --git a/arch/s390/oprofile/backtrace.c b/arch/s390/oprofile/backtrace.c
new file mode 100644
index 000000000..8a6811b2c
--- /dev/null
+++ b/arch/s390/oprofile/backtrace.c
@@ -0,0 +1,77 @@
+/*
+ * S390 Version
+ * Copyright IBM Corp. 2005
+ * Author(s): Andreas Krebbel <Andreas.Krebbel@de.ibm.com>
+ */
+
+#include <linux/oprofile.h>
+
+#include <asm/processor.h> /* for struct stack_frame */
+
+static unsigned long
+__show_trace(unsigned int *depth, unsigned long sp,
+ unsigned long low, unsigned long high)
+{
+ struct stack_frame *sf;
+ struct pt_regs *regs;
+
+ while (*depth) {
+ sp = sp & PSW_ADDR_INSN;
+ if (sp < low || sp > high - sizeof(*sf))
+ return sp;
+ sf = (struct stack_frame *) sp;
+ (*depth)--;
+ oprofile_add_trace(sf->gprs[8] & PSW_ADDR_INSN);
+
+ /* Follow the backchain. */
+ while (*depth) {
+ low = sp;
+ sp = sf->back_chain & PSW_ADDR_INSN;
+ if (!sp)
+ break;
+ if (sp <= low || sp > high - sizeof(*sf))
+ return sp;
+ sf = (struct stack_frame *) sp;
+ (*depth)--;
+ oprofile_add_trace(sf->gprs[8] & PSW_ADDR_INSN);
+
+ }
+
+ if (*depth == 0)
+ break;
+
+ /* Zero backchain detected, check for interrupt frame. */
+ sp = (unsigned long) (sf + 1);
+ if (sp <= low || sp > high - sizeof(*regs))
+ return sp;
+ regs = (struct pt_regs *) sp;
+ (*depth)--;
+ oprofile_add_trace(sf->gprs[8] & PSW_ADDR_INSN);
+ low = sp;
+ sp = regs->gprs[15];
+ }
+ return sp;
+}
+
+void s390_backtrace(struct pt_regs * const regs, unsigned int depth)
+{
+ unsigned long head;
+ struct stack_frame* head_sf;
+
+ if (user_mode(regs))
+ return;
+
+ head = regs->gprs[15];
+ head_sf = (struct stack_frame*)head;
+
+ if (!head_sf->back_chain)
+ return;
+
+ head = head_sf->back_chain;
+
+ head = __show_trace(&depth, head, S390_lowcore.async_stack - ASYNC_SIZE,
+ S390_lowcore.async_stack);
+
+ __show_trace(&depth, head, S390_lowcore.thread_info,
+ S390_lowcore.thread_info + THREAD_SIZE);
+}
diff --git a/arch/s390/oprofile/hwsampler.c b/arch/s390/oprofile/hwsampler.c
new file mode 100644
index 000000000..ff9b4eb34
--- /dev/null
+++ b/arch/s390/oprofile/hwsampler.c
@@ -0,0 +1,1178 @@
+/*
+ * Copyright IBM Corp. 2010
+ * Author: Heinz Graalfs <graalfs@de.ibm.com>
+ */
+
+#include <linux/kernel_stat.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/smp.h>
+#include <linux/errno.h>
+#include <linux/workqueue.h>
+#include <linux/interrupt.h>
+#include <linux/notifier.h>
+#include <linux/cpu.h>
+#include <linux/semaphore.h>
+#include <linux/oom.h>
+#include <linux/oprofile.h>
+
+#include <asm/facility.h>
+#include <asm/cpu_mf.h>
+#include <asm/irq.h>
+
+#include "hwsampler.h"
+#include "op_counter.h"
+
+#define MAX_NUM_SDB 511
+#define MIN_NUM_SDB 1
+
+DECLARE_PER_CPU(struct hws_cpu_buffer, sampler_cpu_buffer);
+
+struct hws_execute_parms {
+ void *buffer;
+ signed int rc;
+};
+
+DEFINE_PER_CPU(struct hws_cpu_buffer, sampler_cpu_buffer);
+EXPORT_PER_CPU_SYMBOL(sampler_cpu_buffer);
+
+static DEFINE_MUTEX(hws_sem);
+static DEFINE_MUTEX(hws_sem_oom);
+
+static unsigned char hws_flush_all;
+static unsigned int hws_oom;
+static unsigned int hws_alert;
+static struct workqueue_struct *hws_wq;
+
+static unsigned int hws_state;
+enum {
+ HWS_INIT = 1,
+ HWS_DEALLOCATED,
+ HWS_STOPPED,
+ HWS_STARTED,
+ HWS_STOPPING };
+
+/* set to 1 if called by kernel during memory allocation */
+static unsigned char oom_killer_was_active;
+/* size of SDBT and SDB as of allocate API */
+static unsigned long num_sdbt = 100;
+static unsigned long num_sdb = 511;
+/* sampling interval (machine cycles) */
+static unsigned long interval;
+
+static unsigned long min_sampler_rate;
+static unsigned long max_sampler_rate;
+
+static void execute_qsi(void *parms)
+{
+ struct hws_execute_parms *ep = parms;
+
+ ep->rc = qsi(ep->buffer);
+}
+
+static void execute_ssctl(void *parms)
+{
+ struct hws_execute_parms *ep = parms;
+
+ ep->rc = lsctl(ep->buffer);
+}
+
+static int smp_ctl_ssctl_stop(int cpu)
+{
+ int rc;
+ struct hws_execute_parms ep;
+ struct hws_cpu_buffer *cb;
+
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+
+ cb->ssctl.es = 0;
+ cb->ssctl.cs = 0;
+
+ ep.buffer = &cb->ssctl;
+ smp_call_function_single(cpu, execute_ssctl, &ep, 1);
+ rc = ep.rc;
+ if (rc) {
+ printk(KERN_ERR "hwsampler: CPU %d CPUMF SSCTL failed.\n", cpu);
+ dump_stack();
+ }
+
+ ep.buffer = &cb->qsi;
+ smp_call_function_single(cpu, execute_qsi, &ep, 1);
+
+ if (cb->qsi.es || cb->qsi.cs) {
+ printk(KERN_EMERG "CPUMF sampling did not stop properly.\n");
+ dump_stack();
+ }
+
+ return rc;
+}
+
+static int smp_ctl_ssctl_deactivate(int cpu)
+{
+ int rc;
+ struct hws_execute_parms ep;
+ struct hws_cpu_buffer *cb;
+
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+
+ cb->ssctl.es = 1;
+ cb->ssctl.cs = 0;
+
+ ep.buffer = &cb->ssctl;
+ smp_call_function_single(cpu, execute_ssctl, &ep, 1);
+ rc = ep.rc;
+ if (rc)
+ printk(KERN_ERR "hwsampler: CPU %d CPUMF SSCTL failed.\n", cpu);
+
+ ep.buffer = &cb->qsi;
+ smp_call_function_single(cpu, execute_qsi, &ep, 1);
+
+ if (cb->qsi.cs)
+ printk(KERN_EMERG "CPUMF sampling was not set inactive.\n");
+
+ return rc;
+}
+
+static int smp_ctl_ssctl_enable_activate(int cpu, unsigned long interval)
+{
+ int rc;
+ struct hws_execute_parms ep;
+ struct hws_cpu_buffer *cb;
+
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+
+ cb->ssctl.h = 1;
+ cb->ssctl.tear = cb->first_sdbt;
+ cb->ssctl.dear = *(unsigned long *) cb->first_sdbt;
+ cb->ssctl.interval = interval;
+ cb->ssctl.es = 1;
+ cb->ssctl.cs = 1;
+
+ ep.buffer = &cb->ssctl;
+ smp_call_function_single(cpu, execute_ssctl, &ep, 1);
+ rc = ep.rc;
+ if (rc)
+ printk(KERN_ERR "hwsampler: CPU %d CPUMF SSCTL failed.\n", cpu);
+
+ ep.buffer = &cb->qsi;
+ smp_call_function_single(cpu, execute_qsi, &ep, 1);
+ if (ep.rc)
+ printk(KERN_ERR "hwsampler: CPU %d CPUMF QSI failed.\n", cpu);
+
+ return rc;
+}
+
+static int smp_ctl_qsi(int cpu)
+{
+ struct hws_execute_parms ep;
+ struct hws_cpu_buffer *cb;
+
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+
+ ep.buffer = &cb->qsi;
+ smp_call_function_single(cpu, execute_qsi, &ep, 1);
+
+ return ep.rc;
+}
+
+static void hws_ext_handler(struct ext_code ext_code,
+ unsigned int param32, unsigned long param64)
+{
+ struct hws_cpu_buffer *cb = this_cpu_ptr(&sampler_cpu_buffer);
+
+ if (!(param32 & CPU_MF_INT_SF_MASK))
+ return;
+
+ if (!hws_alert)
+ return;
+
+ inc_irq_stat(IRQEXT_CMS);
+ atomic_xchg(&cb->ext_params, atomic_read(&cb->ext_params) | param32);
+
+ if (hws_wq)
+ queue_work(hws_wq, &cb->worker);
+}
+
+static void worker(struct work_struct *work);
+
+static void add_samples_to_oprofile(unsigned cpu, unsigned long *,
+ unsigned long *dear);
+
+static void init_all_cpu_buffers(void)
+{
+ int cpu;
+ struct hws_cpu_buffer *cb;
+
+ for_each_online_cpu(cpu) {
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+ memset(cb, 0, sizeof(struct hws_cpu_buffer));
+ }
+}
+
+static void prepare_cpu_buffers(void)
+{
+ struct hws_cpu_buffer *cb;
+ int cpu;
+
+ for_each_online_cpu(cpu) {
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+ atomic_set(&cb->ext_params, 0);
+ cb->worker_entry = 0;
+ cb->sample_overflow = 0;
+ cb->req_alert = 0;
+ cb->incorrect_sdbt_entry = 0;
+ cb->invalid_entry_address = 0;
+ cb->loss_of_sample_data = 0;
+ cb->sample_auth_change_alert = 0;
+ cb->finish = 0;
+ cb->oom = 0;
+ cb->stop_mode = 0;
+ }
+}
+
+/*
+ * allocate_sdbt() - allocate sampler memory
+ * @cpu: the cpu for which sampler memory is allocated
+ *
+ * A 4K page is allocated for each requested SDBT.
+ * A maximum of 511 4K pages are allocated for the SDBs in each of the SDBTs.
+ * Set ALERT_REQ mask in each SDBs trailer.
+ * Returns zero if successful, <0 otherwise.
+ */
+static int allocate_sdbt(int cpu)
+{
+ int j, k, rc;
+ unsigned long *sdbt;
+ unsigned long sdb;
+ unsigned long *tail;
+ unsigned long *trailer;
+ struct hws_cpu_buffer *cb;
+
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+
+ if (cb->first_sdbt)
+ return -EINVAL;
+
+ sdbt = NULL;
+ tail = sdbt;
+
+ for (j = 0; j < num_sdbt; j++) {
+ sdbt = (unsigned long *)get_zeroed_page(GFP_KERNEL);
+
+ mutex_lock(&hws_sem_oom);
+ /* OOM killer might have been activated */
+ barrier();
+ if (oom_killer_was_active || !sdbt) {
+ if (sdbt)
+ free_page((unsigned long)sdbt);
+
+ goto allocate_sdbt_error;
+ }
+ if (cb->first_sdbt == 0)
+ cb->first_sdbt = (unsigned long)sdbt;
+
+ /* link current page to tail of chain */
+ if (tail)
+ *tail = (unsigned long)(void *)sdbt + 1;
+
+ mutex_unlock(&hws_sem_oom);
+
+ for (k = 0; k < num_sdb; k++) {
+ /* get and set SDB page */
+ sdb = get_zeroed_page(GFP_KERNEL);
+
+ mutex_lock(&hws_sem_oom);
+ /* OOM killer might have been activated */
+ barrier();
+ if (oom_killer_was_active || !sdb) {
+ if (sdb)
+ free_page(sdb);
+
+ goto allocate_sdbt_error;
+ }
+ *sdbt = sdb;
+ trailer = trailer_entry_ptr(*sdbt);
+ *trailer = SDB_TE_ALERT_REQ_MASK;
+ sdbt++;
+ mutex_unlock(&hws_sem_oom);
+ }
+ tail = sdbt;
+ }
+ mutex_lock(&hws_sem_oom);
+ if (oom_killer_was_active)
+ goto allocate_sdbt_error;
+
+ rc = 0;
+ if (tail)
+ *tail = (unsigned long)
+ ((void *)cb->first_sdbt) + 1;
+
+allocate_sdbt_exit:
+ mutex_unlock(&hws_sem_oom);
+ return rc;
+
+allocate_sdbt_error:
+ rc = -ENOMEM;
+ goto allocate_sdbt_exit;
+}
+
+/*
+ * deallocate_sdbt() - deallocate all sampler memory
+ *
+ * For each online CPU all SDBT trees are deallocated.
+ * Returns the number of freed pages.
+ */
+static int deallocate_sdbt(void)
+{
+ int cpu;
+ int counter;
+
+ counter = 0;
+
+ for_each_online_cpu(cpu) {
+ unsigned long start;
+ unsigned long sdbt;
+ unsigned long *curr;
+ struct hws_cpu_buffer *cb;
+
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+
+ if (!cb->first_sdbt)
+ continue;
+
+ sdbt = cb->first_sdbt;
+ curr = (unsigned long *) sdbt;
+ start = sdbt;
+
+ /* we'll free the SDBT after all SDBs are processed... */
+ while (1) {
+ if (!*curr || !sdbt)
+ break;
+
+ /* watch for link entry reset if found */
+ if (is_link_entry(curr)) {
+ curr = get_next_sdbt(curr);
+ if (sdbt)
+ free_page(sdbt);
+
+ /* we are done if we reach the start */
+ if ((unsigned long) curr == start)
+ break;
+ else
+ sdbt = (unsigned long) curr;
+ } else {
+ /* process SDB pointer */
+ if (*curr) {
+ free_page(*curr);
+ curr++;
+ }
+ }
+ counter++;
+ }
+ cb->first_sdbt = 0;
+ }
+ return counter;
+}
+
+static int start_sampling(int cpu)
+{
+ int rc;
+ struct hws_cpu_buffer *cb;
+
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+ rc = smp_ctl_ssctl_enable_activate(cpu, interval);
+ if (rc) {
+ printk(KERN_INFO "hwsampler: CPU %d ssctl failed.\n", cpu);
+ goto start_exit;
+ }
+
+ rc = -EINVAL;
+ if (!cb->qsi.es) {
+ printk(KERN_INFO "hwsampler: CPU %d ssctl not enabled.\n", cpu);
+ goto start_exit;
+ }
+
+ if (!cb->qsi.cs) {
+ printk(KERN_INFO "hwsampler: CPU %d ssctl not active.\n", cpu);
+ goto start_exit;
+ }
+
+ printk(KERN_INFO
+ "hwsampler: CPU %d, CPUMF Sampling started, interval %lu.\n",
+ cpu, interval);
+
+ rc = 0;
+
+start_exit:
+ return rc;
+}
+
+static int stop_sampling(int cpu)
+{
+ unsigned long v;
+ int rc;
+ struct hws_cpu_buffer *cb;
+
+ rc = smp_ctl_qsi(cpu);
+ WARN_ON(rc);
+
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+ if (!rc && !cb->qsi.es)
+ printk(KERN_INFO "hwsampler: CPU %d, already stopped.\n", cpu);
+
+ rc = smp_ctl_ssctl_stop(cpu);
+ if (rc) {
+ printk(KERN_INFO "hwsampler: CPU %d, ssctl stop error %d.\n",
+ cpu, rc);
+ goto stop_exit;
+ }
+
+ printk(KERN_INFO "hwsampler: CPU %d, CPUMF Sampling stopped.\n", cpu);
+
+stop_exit:
+ v = cb->req_alert;
+ if (v)
+ printk(KERN_ERR "hwsampler: CPU %d CPUMF Request alert,"
+ " count=%lu.\n", cpu, v);
+
+ v = cb->loss_of_sample_data;
+ if (v)
+ printk(KERN_ERR "hwsampler: CPU %d CPUMF Loss of sample data,"
+ " count=%lu.\n", cpu, v);
+
+ v = cb->invalid_entry_address;
+ if (v)
+ printk(KERN_ERR "hwsampler: CPU %d CPUMF Invalid entry address,"
+ " count=%lu.\n", cpu, v);
+
+ v = cb->incorrect_sdbt_entry;
+ if (v)
+ printk(KERN_ERR
+ "hwsampler: CPU %d CPUMF Incorrect SDBT address,"
+ " count=%lu.\n", cpu, v);
+
+ v = cb->sample_auth_change_alert;
+ if (v)
+ printk(KERN_ERR
+ "hwsampler: CPU %d CPUMF Sample authorization change,"
+ " count=%lu.\n", cpu, v);
+
+ return rc;
+}
+
+static int check_hardware_prerequisites(void)
+{
+ if (!test_facility(68))
+ return -EOPNOTSUPP;
+ return 0;
+}
+/*
+ * hws_oom_callback() - the OOM callback function
+ *
+ * In case the callback is invoked during memory allocation for the
+ * hw sampler, all obtained memory is deallocated and a flag is set
+ * so main sampler memory allocation can exit with a failure code.
+ * In case the callback is invoked during sampling the hw sampler
+ * is deactivated for all CPUs.
+ */
+static int hws_oom_callback(struct notifier_block *nfb,
+ unsigned long dummy, void *parm)
+{
+ unsigned long *freed;
+ int cpu;
+ struct hws_cpu_buffer *cb;
+
+ freed = parm;
+
+ mutex_lock(&hws_sem_oom);
+
+ if (hws_state == HWS_DEALLOCATED) {
+ /* during memory allocation */
+ if (oom_killer_was_active == 0) {
+ oom_killer_was_active = 1;
+ *freed += deallocate_sdbt();
+ }
+ } else {
+ int i;
+ cpu = get_cpu();
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+
+ if (!cb->oom) {
+ for_each_online_cpu(i) {
+ smp_ctl_ssctl_deactivate(i);
+ cb->oom = 1;
+ }
+ cb->finish = 1;
+
+ printk(KERN_INFO
+ "hwsampler: CPU %d, OOM notify during CPUMF Sampling.\n",
+ cpu);
+ }
+ }
+
+ mutex_unlock(&hws_sem_oom);
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block hws_oom_notifier = {
+ .notifier_call = hws_oom_callback
+};
+
+static int hws_cpu_callback(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
+{
+ /* We do not have sampler space available for all possible CPUs.
+ All CPUs should be online when hw sampling is activated. */
+ return (hws_state <= HWS_DEALLOCATED) ? NOTIFY_OK : NOTIFY_BAD;
+}
+
+static struct notifier_block hws_cpu_notifier = {
+ .notifier_call = hws_cpu_callback
+};
+
+/**
+ * hwsampler_deactivate() - set hardware sampling temporarily inactive
+ * @cpu: specifies the CPU to be set inactive.
+ *
+ * Returns 0 on success, !0 on failure.
+ */
+int hwsampler_deactivate(unsigned int cpu)
+{
+ /*
+ * Deactivate hw sampling temporarily and flush the buffer
+ * by pushing all the pending samples to oprofile buffer.
+ *
+ * This function can be called under one of the following conditions:
+ * Memory unmap, task is exiting.
+ */
+ int rc;
+ struct hws_cpu_buffer *cb;
+
+ rc = 0;
+ mutex_lock(&hws_sem);
+
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+ if (hws_state == HWS_STARTED) {
+ rc = smp_ctl_qsi(cpu);
+ WARN_ON(rc);
+ if (cb->qsi.cs) {
+ rc = smp_ctl_ssctl_deactivate(cpu);
+ if (rc) {
+ printk(KERN_INFO
+ "hwsampler: CPU %d, CPUMF Deactivation failed.\n", cpu);
+ cb->finish = 1;
+ hws_state = HWS_STOPPING;
+ } else {
+ hws_flush_all = 1;
+ /* Add work to queue to read pending samples.*/
+ queue_work_on(cpu, hws_wq, &cb->worker);
+ }
+ }
+ }
+ mutex_unlock(&hws_sem);
+
+ if (hws_wq)
+ flush_workqueue(hws_wq);
+
+ return rc;
+}
+
+/**
+ * hwsampler_activate() - activate/resume hardware sampling which was deactivated
+ * @cpu: specifies the CPU to be set active.
+ *
+ * Returns 0 on success, !0 on failure.
+ */
+int hwsampler_activate(unsigned int cpu)
+{
+ /*
+ * Re-activate hw sampling. This should be called in pair with
+ * hwsampler_deactivate().
+ */
+ int rc;
+ struct hws_cpu_buffer *cb;
+
+ rc = 0;
+ mutex_lock(&hws_sem);
+
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+ if (hws_state == HWS_STARTED) {
+ rc = smp_ctl_qsi(cpu);
+ WARN_ON(rc);
+ if (!cb->qsi.cs) {
+ hws_flush_all = 0;
+ rc = smp_ctl_ssctl_enable_activate(cpu, interval);
+ if (rc) {
+ printk(KERN_ERR
+ "CPU %d, CPUMF activate sampling failed.\n",
+ cpu);
+ }
+ }
+ }
+
+ mutex_unlock(&hws_sem);
+
+ return rc;
+}
+
+static int check_qsi_on_setup(void)
+{
+ int rc;
+ unsigned int cpu;
+ struct hws_cpu_buffer *cb;
+
+ for_each_online_cpu(cpu) {
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+ rc = smp_ctl_qsi(cpu);
+ WARN_ON(rc);
+ if (rc)
+ return -EOPNOTSUPP;
+
+ if (!cb->qsi.as) {
+ printk(KERN_INFO "hwsampler: CPUMF sampling is not authorized.\n");
+ return -EINVAL;
+ }
+
+ if (cb->qsi.es) {
+ printk(KERN_WARNING "hwsampler: CPUMF is still enabled.\n");
+ rc = smp_ctl_ssctl_stop(cpu);
+ if (rc)
+ return -EINVAL;
+
+ printk(KERN_INFO
+ "CPU %d, CPUMF Sampling stopped now.\n", cpu);
+ }
+ }
+ return 0;
+}
+
+static int check_qsi_on_start(void)
+{
+ unsigned int cpu;
+ int rc;
+ struct hws_cpu_buffer *cb;
+
+ for_each_online_cpu(cpu) {
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+ rc = smp_ctl_qsi(cpu);
+ WARN_ON(rc);
+
+ if (!cb->qsi.as)
+ return -EINVAL;
+
+ if (cb->qsi.es)
+ return -EINVAL;
+
+ if (cb->qsi.cs)
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static void worker_on_start(unsigned int cpu)
+{
+ struct hws_cpu_buffer *cb;
+
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+ cb->worker_entry = cb->first_sdbt;
+}
+
+static int worker_check_error(unsigned int cpu, int ext_params)
+{
+ int rc;
+ unsigned long *sdbt;
+ struct hws_cpu_buffer *cb;
+
+ rc = 0;
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+ sdbt = (unsigned long *) cb->worker_entry;
+
+ if (!sdbt || !*sdbt)
+ return -EINVAL;
+
+ if (ext_params & CPU_MF_INT_SF_PRA)
+ cb->req_alert++;
+
+ if (ext_params & CPU_MF_INT_SF_LSDA)
+ cb->loss_of_sample_data++;
+
+ if (ext_params & CPU_MF_INT_SF_IAE) {
+ cb->invalid_entry_address++;
+ rc = -EINVAL;
+ }
+
+ if (ext_params & CPU_MF_INT_SF_ISE) {
+ cb->incorrect_sdbt_entry++;
+ rc = -EINVAL;
+ }
+
+ if (ext_params & CPU_MF_INT_SF_SACA) {
+ cb->sample_auth_change_alert++;
+ rc = -EINVAL;
+ }
+
+ return rc;
+}
+
+static void worker_on_finish(unsigned int cpu)
+{
+ int rc, i;
+ struct hws_cpu_buffer *cb;
+
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+
+ if (cb->finish) {
+ rc = smp_ctl_qsi(cpu);
+ WARN_ON(rc);
+ if (cb->qsi.es) {
+ printk(KERN_INFO
+ "hwsampler: CPU %d, CPUMF Stop/Deactivate sampling.\n",
+ cpu);
+ rc = smp_ctl_ssctl_stop(cpu);
+ if (rc)
+ printk(KERN_INFO
+ "hwsampler: CPU %d, CPUMF Deactivation failed.\n",
+ cpu);
+
+ for_each_online_cpu(i) {
+ if (i == cpu)
+ continue;
+ if (!cb->finish) {
+ cb->finish = 1;
+ queue_work_on(i, hws_wq,
+ &cb->worker);
+ }
+ }
+ }
+ }
+}
+
+static void worker_on_interrupt(unsigned int cpu)
+{
+ unsigned long *sdbt;
+ unsigned char done;
+ struct hws_cpu_buffer *cb;
+
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+
+ sdbt = (unsigned long *) cb->worker_entry;
+
+ done = 0;
+ /* do not proceed if stop was entered,
+ * forget the buffers not yet processed */
+ while (!done && !cb->stop_mode) {
+ unsigned long *trailer;
+ struct hws_trailer_entry *te;
+ unsigned long *dear = 0;
+
+ trailer = trailer_entry_ptr(*sdbt);
+ /* leave loop if no more work to do */
+ if (!(*trailer & SDB_TE_BUFFER_FULL_MASK)) {
+ done = 1;
+ if (!hws_flush_all)
+ continue;
+ }
+
+ te = (struct hws_trailer_entry *)trailer;
+ cb->sample_overflow += te->overflow;
+
+ add_samples_to_oprofile(cpu, sdbt, dear);
+
+ /* reset trailer */
+ xchg((unsigned char *) te, 0x40);
+
+ /* advance to next sdb slot in current sdbt */
+ sdbt++;
+ /* in case link bit is set use address w/o link bit */
+ if (is_link_entry(sdbt))
+ sdbt = get_next_sdbt(sdbt);
+
+ cb->worker_entry = (unsigned long)sdbt;
+ }
+}
+
+static void add_samples_to_oprofile(unsigned int cpu, unsigned long *sdbt,
+ unsigned long *dear)
+{
+ struct hws_basic_entry *sample_data_ptr;
+ unsigned long *trailer;
+
+ trailer = trailer_entry_ptr(*sdbt);
+ if (dear) {
+ if (dear > trailer)
+ return;
+ trailer = dear;
+ }
+
+ sample_data_ptr = (struct hws_basic_entry *)(*sdbt);
+
+ while ((unsigned long *)sample_data_ptr < trailer) {
+ struct pt_regs *regs = NULL;
+ struct task_struct *tsk = NULL;
+
+ /*
+ * Check sampling mode, 1 indicates basic (=customer) sampling
+ * mode.
+ */
+ if (sample_data_ptr->def != 1) {
+ /* sample slot is not yet written */
+ break;
+ } else {
+ /* make sure we don't use it twice,
+ * the next time the sampler will set it again */
+ sample_data_ptr->def = 0;
+ }
+
+ /* Get pt_regs. */
+ if (sample_data_ptr->P == 1) {
+ /* userspace sample */
+ unsigned int pid = sample_data_ptr->prim_asn;
+ if (!counter_config.user)
+ goto skip_sample;
+ rcu_read_lock();
+ tsk = pid_task(find_vpid(pid), PIDTYPE_PID);
+ if (tsk)
+ regs = task_pt_regs(tsk);
+ rcu_read_unlock();
+ } else {
+ /* kernelspace sample */
+ if (!counter_config.kernel)
+ goto skip_sample;
+ regs = task_pt_regs(current);
+ }
+
+ mutex_lock(&hws_sem);
+ oprofile_add_ext_hw_sample(sample_data_ptr->ia, regs, 0,
+ !sample_data_ptr->P, tsk);
+ mutex_unlock(&hws_sem);
+ skip_sample:
+ sample_data_ptr++;
+ }
+}
+
+static void worker(struct work_struct *work)
+{
+ unsigned int cpu;
+ int ext_params;
+ struct hws_cpu_buffer *cb;
+
+ cb = container_of(work, struct hws_cpu_buffer, worker);
+ cpu = smp_processor_id();
+ ext_params = atomic_xchg(&cb->ext_params, 0);
+
+ if (!cb->worker_entry)
+ worker_on_start(cpu);
+
+ if (worker_check_error(cpu, ext_params))
+ return;
+
+ if (!cb->finish)
+ worker_on_interrupt(cpu);
+
+ if (cb->finish)
+ worker_on_finish(cpu);
+}
+
+/**
+ * hwsampler_allocate() - allocate memory for the hardware sampler
+ * @sdbt: number of SDBTs per online CPU (must be > 0)
+ * @sdb: number of SDBs per SDBT (minimum 1, maximum 511)
+ *
+ * Returns 0 on success, !0 on failure.
+ */
+int hwsampler_allocate(unsigned long sdbt, unsigned long sdb)
+{
+ int cpu, rc;
+ mutex_lock(&hws_sem);
+
+ rc = -EINVAL;
+ if (hws_state != HWS_DEALLOCATED)
+ goto allocate_exit;
+
+ if (sdbt < 1)
+ goto allocate_exit;
+
+ if (sdb > MAX_NUM_SDB || sdb < MIN_NUM_SDB)
+ goto allocate_exit;
+
+ num_sdbt = sdbt;
+ num_sdb = sdb;
+
+ oom_killer_was_active = 0;
+ register_oom_notifier(&hws_oom_notifier);
+
+ for_each_online_cpu(cpu) {
+ if (allocate_sdbt(cpu)) {
+ unregister_oom_notifier(&hws_oom_notifier);
+ goto allocate_error;
+ }
+ }
+ unregister_oom_notifier(&hws_oom_notifier);
+ if (oom_killer_was_active)
+ goto allocate_error;
+
+ hws_state = HWS_STOPPED;
+ rc = 0;
+
+allocate_exit:
+ mutex_unlock(&hws_sem);
+ return rc;
+
+allocate_error:
+ rc = -ENOMEM;
+ printk(KERN_ERR "hwsampler: CPUMF Memory allocation failed.\n");
+ goto allocate_exit;
+}
+
+/**
+ * hwsampler_deallocate() - deallocate hardware sampler memory
+ *
+ * Returns 0 on success, !0 on failure.
+ */
+int hwsampler_deallocate(void)
+{
+ int rc;
+
+ mutex_lock(&hws_sem);
+
+ rc = -EINVAL;
+ if (hws_state != HWS_STOPPED)
+ goto deallocate_exit;
+
+ irq_subclass_unregister(IRQ_SUBCLASS_MEASUREMENT_ALERT);
+ hws_alert = 0;
+ deallocate_sdbt();
+
+ hws_state = HWS_DEALLOCATED;
+ rc = 0;
+
+deallocate_exit:
+ mutex_unlock(&hws_sem);
+
+ return rc;
+}
+
+unsigned long hwsampler_query_min_interval(void)
+{
+ return min_sampler_rate;
+}
+
+unsigned long hwsampler_query_max_interval(void)
+{
+ return max_sampler_rate;
+}
+
+unsigned long hwsampler_get_sample_overflow_count(unsigned int cpu)
+{
+ struct hws_cpu_buffer *cb;
+
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+
+ return cb->sample_overflow;
+}
+
+int hwsampler_setup(void)
+{
+ int rc;
+ int cpu;
+ struct hws_cpu_buffer *cb;
+
+ mutex_lock(&hws_sem);
+
+ rc = -EINVAL;
+ if (hws_state)
+ goto setup_exit;
+
+ hws_state = HWS_INIT;
+
+ init_all_cpu_buffers();
+
+ rc = check_hardware_prerequisites();
+ if (rc)
+ goto setup_exit;
+
+ rc = check_qsi_on_setup();
+ if (rc)
+ goto setup_exit;
+
+ rc = -EINVAL;
+ hws_wq = create_workqueue("hwsampler");
+ if (!hws_wq)
+ goto setup_exit;
+
+ register_cpu_notifier(&hws_cpu_notifier);
+
+ for_each_online_cpu(cpu) {
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+ INIT_WORK(&cb->worker, worker);
+ rc = smp_ctl_qsi(cpu);
+ WARN_ON(rc);
+ if (min_sampler_rate != cb->qsi.min_sampl_rate) {
+ if (min_sampler_rate) {
+ printk(KERN_WARNING
+ "hwsampler: different min sampler rate values.\n");
+ if (min_sampler_rate < cb->qsi.min_sampl_rate)
+ min_sampler_rate =
+ cb->qsi.min_sampl_rate;
+ } else
+ min_sampler_rate = cb->qsi.min_sampl_rate;
+ }
+ if (max_sampler_rate != cb->qsi.max_sampl_rate) {
+ if (max_sampler_rate) {
+ printk(KERN_WARNING
+ "hwsampler: different max sampler rate values.\n");
+ if (max_sampler_rate > cb->qsi.max_sampl_rate)
+ max_sampler_rate =
+ cb->qsi.max_sampl_rate;
+ } else
+ max_sampler_rate = cb->qsi.max_sampl_rate;
+ }
+ }
+ register_external_irq(EXT_IRQ_MEASURE_ALERT, hws_ext_handler);
+
+ hws_state = HWS_DEALLOCATED;
+ rc = 0;
+
+setup_exit:
+ mutex_unlock(&hws_sem);
+ return rc;
+}
+
+int hwsampler_shutdown(void)
+{
+ int rc;
+
+ mutex_lock(&hws_sem);
+
+ rc = -EINVAL;
+ if (hws_state == HWS_DEALLOCATED || hws_state == HWS_STOPPED) {
+ mutex_unlock(&hws_sem);
+
+ if (hws_wq)
+ flush_workqueue(hws_wq);
+
+ mutex_lock(&hws_sem);
+
+ if (hws_state == HWS_STOPPED) {
+ irq_subclass_unregister(IRQ_SUBCLASS_MEASUREMENT_ALERT);
+ hws_alert = 0;
+ deallocate_sdbt();
+ }
+ if (hws_wq) {
+ destroy_workqueue(hws_wq);
+ hws_wq = NULL;
+ }
+
+ unregister_external_irq(EXT_IRQ_MEASURE_ALERT, hws_ext_handler);
+ hws_state = HWS_INIT;
+ rc = 0;
+ }
+ mutex_unlock(&hws_sem);
+
+ unregister_cpu_notifier(&hws_cpu_notifier);
+
+ return rc;
+}
+
+/**
+ * hwsampler_start_all() - start hardware sampling on all online CPUs
+ * @rate: specifies the used interval when samples are taken
+ *
+ * Returns 0 on success, !0 on failure.
+ */
+int hwsampler_start_all(unsigned long rate)
+{
+ int rc, cpu;
+
+ mutex_lock(&hws_sem);
+
+ hws_oom = 0;
+
+ rc = -EINVAL;
+ if (hws_state != HWS_STOPPED)
+ goto start_all_exit;
+
+ interval = rate;
+
+ /* fail if rate is not valid */
+ if (interval < min_sampler_rate || interval > max_sampler_rate)
+ goto start_all_exit;
+
+ rc = check_qsi_on_start();
+ if (rc)
+ goto start_all_exit;
+
+ prepare_cpu_buffers();
+
+ for_each_online_cpu(cpu) {
+ rc = start_sampling(cpu);
+ if (rc)
+ break;
+ }
+ if (rc) {
+ for_each_online_cpu(cpu) {
+ stop_sampling(cpu);
+ }
+ goto start_all_exit;
+ }
+ hws_state = HWS_STARTED;
+ rc = 0;
+
+start_all_exit:
+ mutex_unlock(&hws_sem);
+
+ if (rc)
+ return rc;
+
+ register_oom_notifier(&hws_oom_notifier);
+ hws_oom = 1;
+ hws_flush_all = 0;
+ /* now let them in, 1407 CPUMF external interrupts */
+ hws_alert = 1;
+ irq_subclass_register(IRQ_SUBCLASS_MEASUREMENT_ALERT);
+
+ return 0;
+}
+
+/**
+ * hwsampler_stop_all() - stop hardware sampling on all online CPUs
+ *
+ * Returns 0 on success, !0 on failure.
+ */
+int hwsampler_stop_all(void)
+{
+ int tmp_rc, rc, cpu;
+ struct hws_cpu_buffer *cb;
+
+ mutex_lock(&hws_sem);
+
+ rc = 0;
+ if (hws_state == HWS_INIT) {
+ mutex_unlock(&hws_sem);
+ return 0;
+ }
+ hws_state = HWS_STOPPING;
+ mutex_unlock(&hws_sem);
+
+ for_each_online_cpu(cpu) {
+ cb = &per_cpu(sampler_cpu_buffer, cpu);
+ cb->stop_mode = 1;
+ tmp_rc = stop_sampling(cpu);
+ if (tmp_rc)
+ rc = tmp_rc;
+ }
+
+ if (hws_wq)
+ flush_workqueue(hws_wq);
+
+ mutex_lock(&hws_sem);
+ if (hws_oom) {
+ unregister_oom_notifier(&hws_oom_notifier);
+ hws_oom = 0;
+ }
+ hws_state = HWS_STOPPED;
+ mutex_unlock(&hws_sem);
+
+ return rc;
+}
diff --git a/arch/s390/oprofile/hwsampler.h b/arch/s390/oprofile/hwsampler.h
new file mode 100644
index 000000000..a483d06f2
--- /dev/null
+++ b/arch/s390/oprofile/hwsampler.h
@@ -0,0 +1,63 @@
+/*
+ * CPUMF HW sampler functions and internal structures
+ *
+ * Copyright IBM Corp. 2010
+ * Author(s): Heinz Graalfs <graalfs@de.ibm.com>
+ */
+
+#ifndef HWSAMPLER_H_
+#define HWSAMPLER_H_
+
+#include <linux/workqueue.h>
+#include <asm/cpu_mf.h>
+
+struct hws_ssctl_request_block /* SET SAMPLING CONTROLS req block */
+{ /* bytes 0 - 7 Bit(s) */
+ unsigned int s:1; /* 0: maximum buffer indicator */
+ unsigned int h:1; /* 1: part. level reserved for VM use*/
+ unsigned long b2_53:52; /* 2-53: zeros */
+ unsigned int es:1; /* 54: sampling enable control */
+ unsigned int b55_61:7; /* 55-61: - zeros */
+ unsigned int cs:1; /* 62: sampling activation control */
+ unsigned int b63:1; /* 63: zero */
+ unsigned long interval; /* 8-15: sampling interval */
+ unsigned long tear; /* 16-23: TEAR contents */
+ unsigned long dear; /* 24-31: DEAR contents */
+ /* 32-63: */
+ unsigned long rsvrd1; /* reserved */
+ unsigned long rsvrd2; /* reserved */
+ unsigned long rsvrd3; /* reserved */
+ unsigned long rsvrd4; /* reserved */
+};
+
+struct hws_cpu_buffer {
+ unsigned long first_sdbt; /* @ of 1st SDB-Table for this CP*/
+ unsigned long worker_entry;
+ unsigned long sample_overflow; /* taken from SDB ... */
+ struct hws_qsi_info_block qsi;
+ struct hws_ssctl_request_block ssctl;
+ struct work_struct worker;
+ atomic_t ext_params;
+ unsigned long req_alert;
+ unsigned long loss_of_sample_data;
+ unsigned long invalid_entry_address;
+ unsigned long incorrect_sdbt_entry;
+ unsigned long sample_auth_change_alert;
+ unsigned int finish:1;
+ unsigned int oom:1;
+ unsigned int stop_mode:1;
+};
+
+int hwsampler_setup(void);
+int hwsampler_shutdown(void);
+int hwsampler_allocate(unsigned long sdbt, unsigned long sdb);
+int hwsampler_deallocate(void);
+unsigned long hwsampler_query_min_interval(void);
+unsigned long hwsampler_query_max_interval(void);
+int hwsampler_start_all(unsigned long interval);
+int hwsampler_stop_all(void);
+int hwsampler_deactivate(unsigned int cpu);
+int hwsampler_activate(unsigned int cpu);
+unsigned long hwsampler_get_sample_overflow_count(unsigned int cpu);
+
+#endif /*HWSAMPLER_H_*/
diff --git a/arch/s390/oprofile/init.c b/arch/s390/oprofile/init.c
new file mode 100644
index 000000000..bc927a09a
--- /dev/null
+++ b/arch/s390/oprofile/init.c
@@ -0,0 +1,513 @@
+/*
+ * S390 Version
+ * Copyright IBM Corp. 2002, 2011
+ * Author(s): Thomas Spatzier (tspat@de.ibm.com)
+ * Author(s): Mahesh Salgaonkar (mahesh@linux.vnet.ibm.com)
+ * Author(s): Heinz Graalfs (graalfs@linux.vnet.ibm.com)
+ * Author(s): Andreas Krebbel (krebbel@linux.vnet.ibm.com)
+ *
+ * @remark Copyright 2002-2011 OProfile authors
+ */
+
+#include <linux/oprofile.h>
+#include <linux/perf_event.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <asm/processor.h>
+
+#include "../../../drivers/oprofile/oprof.h"
+
+extern void s390_backtrace(struct pt_regs * const regs, unsigned int depth);
+
+#include "hwsampler.h"
+#include "op_counter.h"
+
+#define DEFAULT_INTERVAL 4127518
+
+#define DEFAULT_SDBT_BLOCKS 1
+#define DEFAULT_SDB_BLOCKS 511
+
+static unsigned long oprofile_hw_interval = DEFAULT_INTERVAL;
+static unsigned long oprofile_min_interval;
+static unsigned long oprofile_max_interval;
+
+static unsigned long oprofile_sdbt_blocks = DEFAULT_SDBT_BLOCKS;
+static unsigned long oprofile_sdb_blocks = DEFAULT_SDB_BLOCKS;
+
+static int hwsampler_enabled;
+static int hwsampler_running; /* start_mutex must be held to change */
+static int hwsampler_available;
+
+static struct oprofile_operations timer_ops;
+
+struct op_counter_config counter_config;
+
+enum __force_cpu_type {
+ reserved = 0, /* do not force */
+ timer,
+};
+static int force_cpu_type;
+
+static int set_cpu_type(const char *str, struct kernel_param *kp)
+{
+ if (!strcmp(str, "timer")) {
+ force_cpu_type = timer;
+ printk(KERN_INFO "oprofile: forcing timer to be returned "
+ "as cpu type\n");
+ } else {
+ force_cpu_type = 0;
+ }
+
+ return 0;
+}
+module_param_call(cpu_type, set_cpu_type, NULL, NULL, 0);
+MODULE_PARM_DESC(cpu_type, "Force legacy basic mode sampling"
+ "(report cpu_type \"timer\"");
+
+static int __oprofile_hwsampler_start(void)
+{
+ int retval;
+
+ retval = hwsampler_allocate(oprofile_sdbt_blocks, oprofile_sdb_blocks);
+ if (retval)
+ return retval;
+
+ retval = hwsampler_start_all(oprofile_hw_interval);
+ if (retval)
+ hwsampler_deallocate();
+
+ return retval;
+}
+
+static int oprofile_hwsampler_start(void)
+{
+ int retval;
+
+ hwsampler_running = hwsampler_enabled;
+
+ if (!hwsampler_running)
+ return timer_ops.start();
+
+ retval = perf_reserve_sampling();
+ if (retval)
+ return retval;
+
+ retval = __oprofile_hwsampler_start();
+ if (retval)
+ perf_release_sampling();
+
+ return retval;
+}
+
+static void oprofile_hwsampler_stop(void)
+{
+ if (!hwsampler_running) {
+ timer_ops.stop();
+ return;
+ }
+
+ hwsampler_stop_all();
+ hwsampler_deallocate();
+ perf_release_sampling();
+ return;
+}
+
+/*
+ * File ops used for:
+ * /dev/oprofile/0/enabled
+ * /dev/oprofile/hwsampling/hwsampler (cpu_type = timer)
+ */
+
+static ssize_t hwsampler_read(struct file *file, char __user *buf,
+ size_t count, loff_t *offset)
+{
+ return oprofilefs_ulong_to_user(hwsampler_enabled, buf, count, offset);
+}
+
+static ssize_t hwsampler_write(struct file *file, char const __user *buf,
+ size_t count, loff_t *offset)
+{
+ unsigned long val;
+ int retval;
+
+ if (*offset)
+ return -EINVAL;
+
+ retval = oprofilefs_ulong_from_user(&val, buf, count);
+ if (retval <= 0)
+ return retval;
+
+ if (val != 0 && val != 1)
+ return -EINVAL;
+
+ if (oprofile_started)
+ /*
+ * save to do without locking as we set
+ * hwsampler_running in start() when start_mutex is
+ * held
+ */
+ return -EBUSY;
+
+ hwsampler_enabled = val;
+
+ return count;
+}
+
+static const struct file_operations hwsampler_fops = {
+ .read = hwsampler_read,
+ .write = hwsampler_write,
+};
+
+/*
+ * File ops used for:
+ * /dev/oprofile/0/count
+ * /dev/oprofile/hwsampling/hw_interval (cpu_type = timer)
+ *
+ * Make sure that the value is within the hardware range.
+ */
+
+static ssize_t hw_interval_read(struct file *file, char __user *buf,
+ size_t count, loff_t *offset)
+{
+ return oprofilefs_ulong_to_user(oprofile_hw_interval, buf,
+ count, offset);
+}
+
+static ssize_t hw_interval_write(struct file *file, char const __user *buf,
+ size_t count, loff_t *offset)
+{
+ unsigned long val;
+ int retval;
+
+ if (*offset)
+ return -EINVAL;
+ retval = oprofilefs_ulong_from_user(&val, buf, count);
+ if (retval <= 0)
+ return retval;
+ if (val < oprofile_min_interval)
+ oprofile_hw_interval = oprofile_min_interval;
+ else if (val > oprofile_max_interval)
+ oprofile_hw_interval = oprofile_max_interval;
+ else
+ oprofile_hw_interval = val;
+
+ return count;
+}
+
+static const struct file_operations hw_interval_fops = {
+ .read = hw_interval_read,
+ .write = hw_interval_write,
+};
+
+/*
+ * File ops used for:
+ * /dev/oprofile/0/event
+ * Only a single event with number 0 is supported with this counter.
+ *
+ * /dev/oprofile/0/unit_mask
+ * This is a dummy file needed by the user space tools.
+ * No value other than 0 is accepted or returned.
+ */
+
+static ssize_t hwsampler_zero_read(struct file *file, char __user *buf,
+ size_t count, loff_t *offset)
+{
+ return oprofilefs_ulong_to_user(0, buf, count, offset);
+}
+
+static ssize_t hwsampler_zero_write(struct file *file, char const __user *buf,
+ size_t count, loff_t *offset)
+{
+ unsigned long val;
+ int retval;
+
+ if (*offset)
+ return -EINVAL;
+
+ retval = oprofilefs_ulong_from_user(&val, buf, count);
+ if (retval <= 0)
+ return retval;
+ if (val != 0)
+ return -EINVAL;
+ return count;
+}
+
+static const struct file_operations zero_fops = {
+ .read = hwsampler_zero_read,
+ .write = hwsampler_zero_write,
+};
+
+/* /dev/oprofile/0/kernel file ops. */
+
+static ssize_t hwsampler_kernel_read(struct file *file, char __user *buf,
+ size_t count, loff_t *offset)
+{
+ return oprofilefs_ulong_to_user(counter_config.kernel,
+ buf, count, offset);
+}
+
+static ssize_t hwsampler_kernel_write(struct file *file, char const __user *buf,
+ size_t count, loff_t *offset)
+{
+ unsigned long val;
+ int retval;
+
+ if (*offset)
+ return -EINVAL;
+
+ retval = oprofilefs_ulong_from_user(&val, buf, count);
+ if (retval <= 0)
+ return retval;
+
+ if (val != 0 && val != 1)
+ return -EINVAL;
+
+ counter_config.kernel = val;
+
+ return count;
+}
+
+static const struct file_operations kernel_fops = {
+ .read = hwsampler_kernel_read,
+ .write = hwsampler_kernel_write,
+};
+
+/* /dev/oprofile/0/user file ops. */
+
+static ssize_t hwsampler_user_read(struct file *file, char __user *buf,
+ size_t count, loff_t *offset)
+{
+ return oprofilefs_ulong_to_user(counter_config.user,
+ buf, count, offset);
+}
+
+static ssize_t hwsampler_user_write(struct file *file, char const __user *buf,
+ size_t count, loff_t *offset)
+{
+ unsigned long val;
+ int retval;
+
+ if (*offset)
+ return -EINVAL;
+
+ retval = oprofilefs_ulong_from_user(&val, buf, count);
+ if (retval <= 0)
+ return retval;
+
+ if (val != 0 && val != 1)
+ return -EINVAL;
+
+ counter_config.user = val;
+
+ return count;
+}
+
+static const struct file_operations user_fops = {
+ .read = hwsampler_user_read,
+ .write = hwsampler_user_write,
+};
+
+
+/*
+ * File ops used for: /dev/oprofile/timer/enabled
+ * The value always has to be the inverted value of hwsampler_enabled. So
+ * no separate variable is created. That way we do not need locking.
+ */
+
+static ssize_t timer_enabled_read(struct file *file, char __user *buf,
+ size_t count, loff_t *offset)
+{
+ return oprofilefs_ulong_to_user(!hwsampler_enabled, buf, count, offset);
+}
+
+static ssize_t timer_enabled_write(struct file *file, char const __user *buf,
+ size_t count, loff_t *offset)
+{
+ unsigned long val;
+ int retval;
+
+ if (*offset)
+ return -EINVAL;
+
+ retval = oprofilefs_ulong_from_user(&val, buf, count);
+ if (retval <= 0)
+ return retval;
+
+ if (val != 0 && val != 1)
+ return -EINVAL;
+
+ /* Timer cannot be disabled without having hardware sampling. */
+ if (val == 0 && !hwsampler_available)
+ return -EINVAL;
+
+ if (oprofile_started)
+ /*
+ * save to do without locking as we set
+ * hwsampler_running in start() when start_mutex is
+ * held
+ */
+ return -EBUSY;
+
+ hwsampler_enabled = !val;
+
+ return count;
+}
+
+static const struct file_operations timer_enabled_fops = {
+ .read = timer_enabled_read,
+ .write = timer_enabled_write,
+};
+
+
+static int oprofile_create_hwsampling_files(struct dentry *root)
+{
+ struct dentry *dir;
+
+ dir = oprofilefs_mkdir(root, "timer");
+ if (!dir)
+ return -EINVAL;
+
+ oprofilefs_create_file(dir, "enabled", &timer_enabled_fops);
+
+ if (!hwsampler_available)
+ return 0;
+
+ /* reinitialize default values */
+ hwsampler_enabled = 1;
+ counter_config.kernel = 1;
+ counter_config.user = 1;
+
+ if (!force_cpu_type) {
+ /*
+ * Create the counter file system. A single virtual
+ * counter is created which can be used to
+ * enable/disable hardware sampling dynamically from
+ * user space. The user space will configure a single
+ * counter with a single event. The value of 'event'
+ * and 'unit_mask' are not evaluated by the kernel code
+ * and can only be set to 0.
+ */
+
+ dir = oprofilefs_mkdir(root, "0");
+ if (!dir)
+ return -EINVAL;
+
+ oprofilefs_create_file(dir, "enabled", &hwsampler_fops);
+ oprofilefs_create_file(dir, "event", &zero_fops);
+ oprofilefs_create_file(dir, "count", &hw_interval_fops);
+ oprofilefs_create_file(dir, "unit_mask", &zero_fops);
+ oprofilefs_create_file(dir, "kernel", &kernel_fops);
+ oprofilefs_create_file(dir, "user", &user_fops);
+ oprofilefs_create_ulong(dir, "hw_sdbt_blocks",
+ &oprofile_sdbt_blocks);
+
+ } else {
+ /*
+ * Hardware sampling can be used but the cpu_type is
+ * forced to timer in order to deal with legacy user
+ * space tools. The /dev/oprofile/hwsampling fs is
+ * provided in that case.
+ */
+ dir = oprofilefs_mkdir(root, "hwsampling");
+ if (!dir)
+ return -EINVAL;
+
+ oprofilefs_create_file(dir, "hwsampler",
+ &hwsampler_fops);
+ oprofilefs_create_file(dir, "hw_interval",
+ &hw_interval_fops);
+ oprofilefs_create_ro_ulong(dir, "hw_min_interval",
+ &oprofile_min_interval);
+ oprofilefs_create_ro_ulong(dir, "hw_max_interval",
+ &oprofile_max_interval);
+ oprofilefs_create_ulong(dir, "hw_sdbt_blocks",
+ &oprofile_sdbt_blocks);
+ }
+ return 0;
+}
+
+static int oprofile_hwsampler_init(struct oprofile_operations *ops)
+{
+ /*
+ * Initialize the timer mode infrastructure as well in order
+ * to be able to switch back dynamically. oprofile_timer_init
+ * is not supposed to fail.
+ */
+ if (oprofile_timer_init(ops))
+ BUG();
+
+ memcpy(&timer_ops, ops, sizeof(timer_ops));
+ ops->create_files = oprofile_create_hwsampling_files;
+
+ /*
+ * If the user space tools do not support newer cpu types,
+ * the force_cpu_type module parameter
+ * can be used to always return \"timer\" as cpu type.
+ */
+ if (force_cpu_type != timer) {
+ struct cpuid id;
+
+ get_cpu_id (&id);
+
+ switch (id.machine) {
+ case 0x2097: case 0x2098: ops->cpu_type = "s390/z10"; break;
+ case 0x2817: case 0x2818: ops->cpu_type = "s390/z196"; break;
+ case 0x2827: case 0x2828: ops->cpu_type = "s390/zEC12"; break;
+ default: return -ENODEV;
+ }
+ }
+
+ if (hwsampler_setup())
+ return -ENODEV;
+
+ /*
+ * Query the range for the sampling interval from the
+ * hardware.
+ */
+ oprofile_min_interval = hwsampler_query_min_interval();
+ if (oprofile_min_interval == 0)
+ return -ENODEV;
+ oprofile_max_interval = hwsampler_query_max_interval();
+ if (oprofile_max_interval == 0)
+ return -ENODEV;
+
+ /* The initial value should be sane */
+ if (oprofile_hw_interval < oprofile_min_interval)
+ oprofile_hw_interval = oprofile_min_interval;
+ if (oprofile_hw_interval > oprofile_max_interval)
+ oprofile_hw_interval = oprofile_max_interval;
+
+ printk(KERN_INFO "oprofile: System z hardware sampling "
+ "facility found.\n");
+
+ ops->start = oprofile_hwsampler_start;
+ ops->stop = oprofile_hwsampler_stop;
+
+ return 0;
+}
+
+static void oprofile_hwsampler_exit(void)
+{
+ hwsampler_shutdown();
+}
+
+int __init oprofile_arch_init(struct oprofile_operations *ops)
+{
+ ops->backtrace = s390_backtrace;
+
+ /*
+ * -ENODEV is not reported to the caller. The module itself
+ * will use the timer mode sampling as fallback and this is
+ * always available.
+ */
+ hwsampler_available = oprofile_hwsampler_init(ops) == 0;
+
+ return 0;
+}
+
+void oprofile_arch_exit(void)
+{
+ oprofile_hwsampler_exit();
+}
diff --git a/arch/s390/oprofile/op_counter.h b/arch/s390/oprofile/op_counter.h
new file mode 100644
index 000000000..61b2531ee
--- /dev/null
+++ b/arch/s390/oprofile/op_counter.h
@@ -0,0 +1,21 @@
+/*
+ * Copyright IBM Corp. 2011
+ * Author(s): Andreas Krebbel (krebbel@linux.vnet.ibm.com)
+ *
+ * @remark Copyright 2011 OProfile authors
+ */
+
+#ifndef OP_COUNTER_H
+#define OP_COUNTER_H
+
+struct op_counter_config {
+ /* `enabled' maps to the hwsampler_file variable. */
+ /* `count' maps to the oprofile_hw_interval variable. */
+ /* `event' and `unit_mask' are unused. */
+ unsigned long kernel;
+ unsigned long user;
+};
+
+extern struct op_counter_config counter_config;
+
+#endif /* OP_COUNTER_H */