1 files changed, 217 insertions, 174 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 44f916a04065..9ec59f541156 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -101,10 +101,7 @@ static inline void ftrace_enable_cpu(void)
         preempt_enable();
 }
 
-static cpumask_var_t __read_mostly      tracing_buffer_mask;
-
-#define for_each_tracing_cpu(cpu)       \
-        for_each_cpu(cpu, tracing_buffer_mask)
+cpumask_var_t __read_mostly     tracing_buffer_mask;
 
 /*
  * ftrace_dump_on_oops - variable to dump ftrace buffer on oops
@@ -117,9 +114,12 @@ static cpumask_var_t __read_mostly	tracing_buffer_mask;
  *
  * It is default off, but you can enable it with either specifying
  * "ftrace_dump_on_oops" in the kernel command line, or setting
- * /proc/sys/kernel/ftrace_dump_on_oops to true.
+ * /proc/sys/kernel/ftrace_dump_on_oops
+ * Set 1 if you want to dump buffers of all CPUs
+ * Set 2 if you want to dump the buffer of the CPU that triggered oops
  */
-int ftrace_dump_on_oops;
+
+enum ftrace_dump_mode ftrace_dump_on_oops;
 
 static int tracing_set_tracer(const char *buf);
 
@@ -139,8 +139,17 @@ __setup("ftrace=", set_cmdline_ftrace);
 
 static int __init set_ftrace_dump_on_oops(char *str)
 {
-        ftrace_dump_on_oops = 1;
-        return 1;
+        if (*str++ != '=' || !*str) {
+                ftrace_dump_on_oops = DUMP_ALL;
+                return 1;
+        }
+
+        if (!strcmp("orig_cpu", str)) {
+                ftrace_dump_on_oops = DUMP_ORIG;
+                return 1;
+        }
+
+        return 0;
 }
 __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops);
 
@@ -332,7 +341,7 @@ static DECLARE_WAIT_QUEUE_HEAD(trace_wait);
 /* trace_flags holds trace_options default values */
 unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK |
         TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME |
-        TRACE_ITER_GRAPH_TIME;
+        TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD;
 
 static int trace_stop_count;
 static DEFINE_SPINLOCK(tracing_start_lock);
@@ -416,6 +425,7 @@ static const char *trace_options[] = {
         "latency-format",
         "sleep-time",
         "graph-time",
+        "record-cmd",
         NULL
 };
 
@@ -647,6 +657,10 @@ update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
                 return;
 
         WARN_ON_ONCE(!irqs_disabled());
+        if (!current_trace->use_max_tr) {
+                WARN_ON_ONCE(1);
+                return;
+        }
         arch_spin_lock(&ftrace_max_lock);
 
         tr->buffer = max_tr.buffer;
@@ -673,6 +687,11 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
                 return;
 
         WARN_ON_ONCE(!irqs_disabled());
+        if (!current_trace->use_max_tr) {
+                WARN_ON_ONCE(1);
+                return;
+        }
+
         arch_spin_lock(&ftrace_max_lock);
 
         ftrace_disable_cpu();
@@ -717,18 +736,11 @@ __acquires(kernel_lock)
                 return -1;
         }
 
-        if (strlen(type->name) > MAX_TRACER_SIZE) {
+        if (strlen(type->name) >= MAX_TRACER_SIZE) {
                 pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE);
                 return -1;
         }
 
-        /*
-         * When this gets called we hold the BKL which means that
-         * preemption is disabled. Various trace selftests however
-         * need to disable and enable preemption for successful tests.
-         * So we drop the BKL here and grab it after the tests again.
-         */
-        unlock_kernel();
         mutex_lock(&trace_types_lock);
 
         tracing_selftest_running = true;
@@ -810,7 +822,6 @@ __acquires(kernel_lock)
 #endif
 
  out_unlock:
-        lock_kernel();
         return ret;
 }
 
@@ -1319,61 +1330,6 @@ static void __trace_userstack(struct trace_array *tr, unsigned long flags)
 
 #endif /* CONFIG_STACKTRACE */
 
-static void
-ftrace_trace_special(void *__tr,
-                     unsigned long arg1, unsigned long arg2, unsigned long arg3,
-                     int pc)
-{
-        struct ftrace_event_call *call = &event_special;
-        struct ring_buffer_event *event;
-        struct trace_array *tr = __tr;
-        struct ring_buffer *buffer = tr->buffer;
-        struct special_entry *entry;
-
-        event = trace_buffer_lock_reserve(buffer, TRACE_SPECIAL,
-                                          sizeof(*entry), 0, pc);
-        if (!event)
-                return;
-        entry   = ring_buffer_event_data(event);
-        entry->arg1                     = arg1;
-        entry->arg2                     = arg2;
-        entry->arg3                     = arg3;
-
-        if (!filter_check_discard(call, entry, buffer, event))
-                trace_buffer_unlock_commit(buffer, event, 0, pc);
-}
-
-void
-__trace_special(void *__tr, void *__data,
-                unsigned long arg1, unsigned long arg2, unsigned long arg3)
-{
-        ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count());
-}
-
-void
-ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3)
-{
-        struct trace_array *tr = &global_trace;
-        struct trace_array_cpu *data;
-        unsigned long flags;
-        int cpu;
-        int pc;
-
-        if (tracing_disabled)
-                return;
-
-        pc = preempt_count();
-        local_irq_save(flags);
-        cpu = raw_smp_processor_id();
-        data = tr->data[cpu];
-
-        if (likely(atomic_inc_return(&data->disabled) == 1))
-                ftrace_trace_special(tr, arg1, arg2, arg3, pc);
-
-        atomic_dec(&data->disabled);
-        local_irq_restore(flags);
-}
-
 /**
  * trace_vbprintk - write binary msg to tracing buffer
  *
@@ -1392,7 +1348,6 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
         struct bprint_entry *entry;
         unsigned long flags;
         int disable;
-        int resched;
         int cpu, len = 0, size, pc;
 
         if (unlikely(tracing_selftest_running || tracing_disabled))
@@ -1402,7 +1357,7 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
         pause_graph_tracing();
 
         pc = preempt_count();
-        resched = ftrace_preempt_disable();
+        preempt_disable_notrace();
         cpu = raw_smp_processor_id();
         data = tr->data[cpu];
 
@@ -1440,7 +1395,7 @@ out_unlock:
 
 out:
         atomic_dec_return(&data->disabled);
-        ftrace_preempt_enable(resched);
+        preempt_enable_notrace();
         unpause_graph_tracing();
 
         return len;
@@ -1527,11 +1482,6 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
 }
 EXPORT_SYMBOL_GPL(trace_vprintk);
 
-enum trace_file_type {
-        TRACE_FILE_LAT_FMT      = 1,
-        TRACE_FILE_ANNOTATE     = 2,
-};
-
 static void trace_iterator_increment(struct trace_iterator *iter)
 {
         /* Don't allow ftrace to trace into the ring buffers */
@@ -1545,7 +1495,8 @@ static void trace_iterator_increment(struct trace_iterator *iter)
 }
 
 static struct trace_entry *
-peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts)
+peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts,
+                unsigned long *lost_events)
 {
         struct ring_buffer_event *event;
         struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu];
@@ -1556,7 +1507,8 @@ peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts)
         if (buf_iter)
                 event = ring_buffer_iter_peek(buf_iter, ts);
         else
-                event = ring_buffer_peek(iter->tr->buffer, cpu, ts);
+                event = ring_buffer_peek(iter->tr->buffer, cpu, ts,
+                                         lost_events);
 
         ftrace_enable_cpu();
 
@@ -1564,10 +1516,12 @@ peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts)
 }
 
 static struct trace_entry *
-__find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
+__find_next_entry(struct trace_iterator *iter, int *ent_cpu,
+                  unsigned long *missing_events, u64 *ent_ts)
 {
         struct ring_buffer *buffer = iter->tr->buffer;
         struct trace_entry *ent, *next = NULL;
+        unsigned long lost_events = 0, next_lost = 0;
         int cpu_file = iter->cpu_file;
         u64 next_ts = 0, ts;
         int next_cpu = -1;
@@ -1580,7 +1534,7 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
         if (cpu_file > TRACE_PIPE_ALL_CPU) {
                 if (ring_buffer_empty_cpu(buffer, cpu_file))
                         return NULL;
-                ent = peek_next_entry(iter, cpu_file, ent_ts);
+                ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events);
                 if (ent_cpu)
                         *ent_cpu = cpu_file;
 
@@ -1592,7 +1546,7 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
                 if (ring_buffer_empty_cpu(buffer, cpu))
                         continue;
 
-                ent = peek_next_entry(iter, cpu, &ts);
+                ent = peek_next_entry(iter, cpu, &ts, &lost_events);
 
                 /*
                  * Pick the entry with the smallest timestamp:
@@ -1601,6 +1555,7 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
                         next = ent;
                         next_cpu = cpu;
                         next_ts = ts;
+                        next_lost = lost_events;
                 }
         }
 
@@ -1610,6 +1565,9 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
         if (ent_ts)
                 *ent_ts = next_ts;
 
+        if (missing_events)
+                *missing_events = next_lost;
+
         return next;
 }
 
@@ -1617,13 +1575,14 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
                                           int *ent_cpu, u64 *ent_ts)
 {
-        return __find_next_entry(iter, ent_cpu, ent_ts);
+        return __find_next_entry(iter, ent_cpu, NULL, ent_ts);
 }
 
 /* Find the next real entry, and increment the iterator to the next entry */
-static void *find_next_entry_inc(struct trace_iterator *iter)
+void *trace_find_next_entry_inc(struct trace_iterator *iter)
 {
-        iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts);
+        iter->ent = __find_next_entry(iter, &iter->cpu,
+                                      &iter->lost_events, &iter->ts);
 
         if (iter->ent)
                 trace_iterator_increment(iter);
@@ -1635,7 +1594,8 @@ static void trace_consume(struct trace_iterator *iter)
 {
         /* Don't allow ftrace to trace into the ring buffers */
         ftrace_disable_cpu();
-        ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts);
+        ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts,
+                            &iter->lost_events);
         ftrace_enable_cpu();
 }
 
@@ -1654,19 +1614,19 @@ static void *s_next(struct seq_file *m, void *v, loff_t *pos)
                 return NULL;
 
         if (iter->idx < 0)
-                ent = find_next_entry_inc(iter);
+                ent = trace_find_next_entry_inc(iter);
         else
                 ent = iter;
 
         while (ent && iter->idx < i)
-                ent = find_next_entry_inc(iter);
+                ent = trace_find_next_entry_inc(iter);
 
         iter->pos = *pos;
 
         return ent;
 }
 
-static void tracing_iter_reset(struct trace_iterator *iter, int cpu)
+void tracing_iter_reset(struct trace_iterator *iter, int cpu)
 {
         struct trace_array *tr = iter->tr;
         struct ring_buffer_event *event;
@@ -1786,7 +1746,7 @@ static void print_func_help_header(struct seq_file *m)
 }
 
 
-static void
+void
 print_trace_header(struct seq_file *m, struct trace_iterator *iter)
 {
         unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
@@ -1914,7 +1874,7 @@ static enum print_line_t print_trace_fmt(struct trace_iterator *iter)
         }
 
         if (event)
-                return event->trace(iter, sym_flags);
+                return event->funcs->trace(iter, sym_flags, event);
 
         if (!trace_seq_printf(s, "Unknown type %d\n", entry->type))
                 goto partial;
@@ -1940,7 +1900,7 @@ static enum print_line_t print_raw_fmt(struct trace_iterator *iter)
 
         event = ftrace_find_event(entry->type);
         if (event)
-                return event->raw(iter, 0);
+                return event->funcs->raw(iter, 0, event);
 
         if (!trace_seq_printf(s, "%d ?\n", entry->type))
                 goto partial;
@@ -1967,7 +1927,7 @@ static enum print_line_t print_hex_fmt(struct trace_iterator *iter)
 
         event = ftrace_find_event(entry->type);
         if (event) {
-                enum print_line_t ret = event->hex(iter, 0);
+                enum print_line_t ret = event->funcs->hex(iter, 0, event);
                 if (ret != TRACE_TYPE_HANDLED)
                         return ret;
         }
@@ -1992,10 +1952,11 @@ static enum print_line_t print_bin_fmt(struct trace_iterator *iter)
         }
 
         event = ftrace_find_event(entry->type);
-        return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED;
+        return event ? event->funcs->binary(iter, 0, event) :
+                TRACE_TYPE_HANDLED;
 }
 
-static int trace_empty(struct trace_iterator *iter)
+int trace_empty(struct trace_iterator *iter)
 {
         int cpu;
 
@@ -2026,10 +1987,14 @@ static int trace_empty(struct trace_iterator *iter)
 }
 
 /*  Called with trace_event_read_lock() held. */
-static enum print_line_t print_trace_line(struct trace_iterator *iter)
+enum print_line_t print_trace_line(struct trace_iterator *iter)
 {
         enum print_line_t ret;
 
+        if (iter->lost_events)
+                trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n",
+                                 iter->cpu, iter->lost_events);
+
         if (iter->trace && iter->trace->print_line) {
                 ret = iter->trace->print_line(iter);
                 if (ret != TRACE_TYPE_UNHANDLED)
@@ -2058,6 +2023,23 @@ static enum print_line_t print_trace_line(struct trace_iterator *iter)
         return print_trace_fmt(iter);
 }
 
+void trace_default_header(struct seq_file *m)
+{
+        struct trace_iterator *iter = m->private;
+
+        if (iter->iter_flags & TRACE_FILE_LAT_FMT) {
+                /* print nothing if the buffers are empty */
+                if (trace_empty(iter))
+                        return;
+                print_trace_header(m, iter);
+                if (!(trace_flags & TRACE_ITER_VERBOSE))
+                        print_lat_help_header(m);
+        } else {
+                if (!(trace_flags & TRACE_ITER_VERBOSE))
+                        print_func_help_header(m);
+        }
+}
+
 static int s_show(struct seq_file *m, void *v)
 {
         struct trace_iterator *iter = v;
@@ -2070,17 +2052,9 @@ static int s_show(struct seq_file *m, void *v)
                 }
                 if (iter->trace && iter->trace->print_header)
                         iter->trace->print_header(m);
-                else if (iter->iter_flags & TRACE_FILE_LAT_FMT) {
-                        /* print nothing if the buffers are empty */
-                        if (trace_empty(iter))
-                                return 0;
-                        print_trace_header(m, iter);
-                        if (!(trace_flags & TRACE_ITER_VERBOSE))
-                                print_lat_help_header(m);
-                } else {
-                        if (!(trace_flags & TRACE_ITER_VERBOSE))
-                                print_func_help_header(m);
-                }
+                else
+                        trace_default_header(m);
+
         } else if (iter->leftover) {
                 /*
                  * If we filled the seq_file buffer earlier, we
@@ -2166,15 +2140,20 @@ __tracing_open(struct inode *inode, struct file *file)
 
         if (iter->cpu_file == TRACE_PIPE_ALL_CPU) {
                 for_each_tracing_cpu(cpu) {
-
                         iter->buffer_iter[cpu] =
-                                ring_buffer_read_start(iter->tr->buffer, cpu);
+                                ring_buffer_read_prepare(iter->tr->buffer, cpu);
+                }
+                ring_buffer_read_prepare_sync();
+                for_each_tracing_cpu(cpu) {
+                        ring_buffer_read_start(iter->buffer_iter[cpu]);
                         tracing_iter_reset(iter, cpu);
                 }
         } else {
                 cpu = iter->cpu_file;
                 iter->buffer_iter[cpu] =
-                                ring_buffer_read_start(iter->tr->buffer, cpu);
+                        ring_buffer_read_prepare(iter->tr->buffer, cpu);
+                ring_buffer_read_prepare_sync();
+                ring_buffer_read_start(iter->buffer_iter[cpu]);
                 tracing_iter_reset(iter, cpu);
         }
 
@@ -2353,6 +2332,7 @@ static const struct file_operations show_traces_fops = {
         .open           = show_traces_open,
         .read           = seq_read,
         .release        = seq_release,
+        .llseek         = seq_lseek,
 };
 
 /*
@@ -2446,6 +2426,7 @@ static const struct file_operations tracing_cpumask_fops = {
         .open           = tracing_open_generic,
         .read           = tracing_cpumask_read,
         .write          = tracing_cpumask_write,
+        .llseek         = generic_file_llseek,
 };
 
 static int tracing_trace_options_show(struct seq_file *m, void *v)
@@ -2521,6 +2502,9 @@ static void set_tracer_flags(unsigned int mask, int enabled)
                 trace_flags |= mask;
         else
                 trace_flags &= ~mask;
+
+        if (mask == TRACE_ITER_RECORD_CMD)
+                trace_event_enable_cmd_record(enabled);
 }
 
 static ssize_t
@@ -2612,6 +2596,7 @@ tracing_readme_read(struct file *filp, char __user *ubuf,
 static const struct file_operations tracing_readme_fops = {
         .open           = tracing_open_generic,
         .read           = tracing_readme_read,
+        .llseek         = generic_file_llseek,
 };
 
 static ssize_t
@@ -2662,6 +2647,7 @@ tracing_saved_cmdlines_read(struct file *file, char __user *ubuf,
 static const struct file_operations tracing_saved_cmdlines_fops = {
     .open       = tracing_open_generic,
     .read       = tracing_saved_cmdlines_read,
+    .llseek     = generic_file_llseek,
 };
 
 static ssize_t
@@ -2757,6 +2743,9 @@ static int tracing_resize_ring_buffer(unsigned long size)
         if (ret < 0)
                 return ret;
 
+        if (!current_trace->use_max_tr)
+                goto out;
+
         ret = ring_buffer_resize(max_tr.buffer, size);
         if (ret < 0) {
                 int r;
@@ -2784,11 +2773,14 @@ static int tracing_resize_ring_buffer(unsigned long size)
                 return ret;
         }
 
+        max_tr.entries = size;
+ out:
         global_trace.entries = size;
 
         return ret;
 }
 
+
 /**
  * tracing_update_buffers - used by tracing facility to expand ring buffers
  *
@@ -2849,12 +2841,26 @@ static int tracing_set_tracer(const char *buf)
         trace_branch_disable();
         if (current_trace && current_trace->reset)
                 current_trace->reset(tr);
-
+        if (current_trace && current_trace->use_max_tr) {
+                /*
+                 * We don't free the ring buffer. instead, resize it because
+                 * The max_tr ring buffer has some state (e.g. ring->clock) and
+                 * we want preserve it.
+                 */
+                ring_buffer_resize(max_tr.buffer, 1);
+                max_tr.entries = 1;
+        }
         destroy_trace_option_files(topts);
 
         current_trace = t;
 
         topts = create_trace_option_files(current_trace);
+        if (current_trace->use_max_tr) {
+                ret = ring_buffer_resize(max_tr.buffer, global_trace.entries);
+                if (ret < 0)
+                        goto out;
+                max_tr.entries = global_trace.entries;
+        }
 
         if (t->init) {
                 ret = tracer_init(t, tr);
@@ -2991,6 +2997,7 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp)
         if (iter->trace->pipe_open)
                 iter->trace->pipe_open(iter);
 
+        nonseekable_open(inode, filp);
 out:
         mutex_unlock(&trace_types_lock);
         return ret;
@@ -3170,7 +3177,7 @@ waitagain:
 
         trace_event_read_lock();
         trace_access_lock(iter->cpu_file);
-        while (find_next_entry_inc(iter) != NULL) {
+        while (trace_find_next_entry_inc(iter) != NULL) {
                 enum print_line_t ret;
                 int len = iter->seq.len;
 
@@ -3253,7 +3260,7 @@ tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter)
                 if (ret != TRACE_TYPE_NO_CONSUME)
                         trace_consume(iter);
                 rem -= count;
-                if (!find_next_entry_inc(iter)) {
+                if (!trace_find_next_entry_inc(iter))   {
                         rem = 0;
                         iter->ent = NULL;
                         break;
@@ -3269,12 +3276,12 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
                                         size_t len,
                                         unsigned int flags)
 {
-        struct page *pages[PIPE_BUFFERS];
-        struct partial_page partial[PIPE_BUFFERS];
+        struct page *pages_def[PIPE_DEF_BUFFERS];
+        struct partial_page partial_def[PIPE_DEF_BUFFERS];
         struct trace_iterator *iter = filp->private_data;
         struct splice_pipe_desc spd = {
-                .pages          = pages,
-                .partial        = partial,
+                .pages          = pages_def,
+                .partial        = partial_def,
                 .nr_pages       = 0, /* This gets updated below. */
                 .flags          = flags,
                 .ops            = &tracing_pipe_buf_ops,
@@ -3285,6 +3292,9 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
         size_t rem;
         unsigned int i;
 
+        if (splice_grow_spd(pipe, &spd))
+                return -ENOMEM;
+
         /* copy the tracer to avoid using a global lock all around */
         mutex_lock(&trace_types_lock);
         if (unlikely(old_tracer != current_trace && current_trace)) {
@@ -3306,7 +3316,7 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
         if (ret <= 0)
                 goto out_err;
 
-        if (!iter->ent && !find_next_entry_inc(iter)) {
+        if (!iter->ent && !trace_find_next_entry_inc(iter)) {
                 ret = -EFAULT;
                 goto out_err;
         }
@@ -3315,23 +3325,23 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
         trace_access_lock(iter->cpu_file);
 
         /* Fill as many pages as possible. */
-        for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) {
-                pages[i] = alloc_page(GFP_KERNEL);
-                if (!pages[i])
+        for (i = 0, rem = len; i < pipe->buffers && rem; i++) {
+                spd.pages[i] = alloc_page(GFP_KERNEL);
+                if (!spd.pages[i])
                         break;
 
                 rem = tracing_fill_pipe_page(rem, iter);
 
                 /* Copy the data into the page, so we can start over. */
                 ret = trace_seq_to_buffer(&iter->seq,
-                                          page_address(pages[i]),
+                                          page_address(spd.pages[i]),
                                           iter->seq.len);
                 if (ret < 0) {
-                        __free_page(pages[i]);
+                        __free_page(spd.pages[i]);
                         break;
                 }
-                partial[i].offset = 0;
-                partial[i].len = iter->seq.len;
+                spd.partial[i].offset = 0;
+                spd.partial[i].len = iter->seq.len;
 
                 trace_seq_init(&iter->seq);
         }
@@ -3342,12 +3352,14 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
 
         spd.nr_pages = i;
 
-        return splice_to_pipe(pipe, &spd);
+        ret = splice_to_pipe(pipe, &spd);
+out:
+        splice_shrink_spd(pipe, &spd);
+        return ret;
 
 out_err:
         mutex_unlock(&iter->mutex);
-
-        return ret;
+        goto out;
 }
 
 static ssize_t
@@ -3431,7 +3443,6 @@ tracing_entries_write(struct file *filp, const char __user *ubuf,
         }
 
         tracing_start();
-        max_tr.entries = global_trace.entries;
         mutex_unlock(&trace_types_lock);
 
         return cnt;
@@ -3452,6 +3463,7 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
                                         size_t cnt, loff_t *fpos)
 {
         char *buf;
+        size_t written;
 
         if (tracing_disabled)
                 return -EINVAL;
@@ -3473,11 +3485,15 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
         } else
                 buf[cnt] = '\0';
 
-        cnt = mark_printk("%s", buf);
+        written = mark_printk("%s", buf);
         kfree(buf);
-        *fpos += cnt;
+        *fpos += written;
 
-        return cnt;
+        /* don't tell userspace we wrote more - it might confuse them */
+        if (written > cnt)
+                written = cnt;
+
+        return written;
 }
 
 static int tracing_clock_show(struct seq_file *m, void *v)
@@ -3544,18 +3560,21 @@ static const struct file_operations tracing_max_lat_fops = {
         .open           = tracing_open_generic,
         .read           = tracing_max_lat_read,
         .write          = tracing_max_lat_write,
+        .llseek         = generic_file_llseek,
 };
 
 static const struct file_operations tracing_ctrl_fops = {
         .open           = tracing_open_generic,
         .read           = tracing_ctrl_read,
         .write          = tracing_ctrl_write,
+        .llseek         = generic_file_llseek,
 };
 
 static const struct file_operations set_tracer_fops = {
         .open           = tracing_open_generic,
         .read           = tracing_set_trace_read,
         .write          = tracing_set_trace_write,
+        .llseek         = generic_file_llseek,
 };
 
 static const struct file_operations tracing_pipe_fops = {
@@ -3564,17 +3583,20 @@ static const struct file_operations tracing_pipe_fops = {
         .read           = tracing_read_pipe,
         .splice_read    = tracing_splice_read_pipe,
         .release        = tracing_release_pipe,
+        .llseek         = no_llseek,
 };
 
 static const struct file_operations tracing_entries_fops = {
         .open           = tracing_open_generic,
         .read           = tracing_entries_read,
         .write          = tracing_entries_write,
+        .llseek         = generic_file_llseek,
 };
 
 static const struct file_operations tracing_mark_fops = {
         .open           = tracing_open_generic,
         .write          = tracing_mark_write,
+        .llseek         = generic_file_llseek,
 };
 
 static const struct file_operations trace_clock_fops = {
@@ -3620,7 +3642,6 @@ tracing_buffers_read(struct file *filp, char __user *ubuf,
                      size_t count, loff_t *ppos)
 {
         struct ftrace_buffer_info *info = filp->private_data;
-        unsigned int pos;
         ssize_t ret;
         size_t size;
 
@@ -3647,11 +3668,6 @@ tracing_buffers_read(struct file *filp, char __user *ubuf,
         if (ret < 0)
                 return 0;
 
-        pos = ring_buffer_page_len(info->spare);
-
-        if (pos < PAGE_SIZE)
-                memset(info->spare + pos, 0, PAGE_SIZE - pos);
-
 read:
         size = PAGE_SIZE - info->read;
         if (size > count)
@@ -3746,11 +3762,11 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
                             unsigned int flags)
 {
         struct ftrace_buffer_info *info = file->private_data;
-        struct partial_page partial[PIPE_BUFFERS];
-        struct page *pages[PIPE_BUFFERS];
+        struct partial_page partial_def[PIPE_DEF_BUFFERS];
+        struct page *pages_def[PIPE_DEF_BUFFERS];
         struct splice_pipe_desc spd = {
-                .pages          = pages,
-                .partial        = partial,
+                .pages          = pages_def,
+                .partial        = partial_def,
                 .flags          = flags,
                 .ops            = &buffer_pipe_buf_ops,
                 .spd_release    = buffer_spd_release,
@@ -3759,22 +3775,28 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
         int entries, size, i;
         size_t ret;
 
+        if (splice_grow_spd(pipe, &spd))
+                return -ENOMEM;
+
         if (*ppos & (PAGE_SIZE - 1)) {
                 WARN_ONCE(1, "Ftrace: previous read must page-align\n");
-                return -EINVAL;
+                ret = -EINVAL;
+                goto out;
         }
 
         if (len & (PAGE_SIZE - 1)) {
                 WARN_ONCE(1, "Ftrace: splice_read should page-align\n");
-                if (len < PAGE_SIZE)
-                        return -EINVAL;
+                if (len < PAGE_SIZE) {
+                        ret = -EINVAL;
+                        goto out;
+                }
                 len &= PAGE_MASK;
         }
 
         trace_access_lock(info->cpu);
         entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu);
 
-        for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) {
+        for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) {
                 struct page *page;
                 int r;
 
@@ -3829,11 +3851,12 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
                 else
                         ret = 0;
                 /* TODO: block */
-                return ret;
+                goto out;
         }
 
         ret = splice_to_pipe(pipe, &spd);
-
+        splice_shrink_spd(pipe, &spd);
+out:
         return ret;
 }
 
@@ -3879,6 +3902,7 @@ tracing_stats_read(struct file *filp, char __user *ubuf,
 static const struct file_operations tracing_stats_fops = {
         .open           = tracing_open_generic,
         .read           = tracing_stats_read,
+        .llseek         = generic_file_llseek,
 };
 
 #ifdef CONFIG_DYNAMIC_FTRACE
@@ -3915,6 +3939,7 @@ tracing_read_dyn_info(struct file *filp, char __user *ubuf,
 static const struct file_operations tracing_dyn_info_fops = {
         .open           = tracing_open_generic,
         .read           = tracing_read_dyn_info,
+        .llseek         = generic_file_llseek,
 };
 #endif
 
@@ -4068,6 +4093,7 @@ static const struct file_operations trace_options_fops = {
         .open = tracing_open_generic,
         .read = trace_options_read,
         .write = trace_options_write,
+        .llseek = generic_file_llseek,
 };
 
 static ssize_t
@@ -4119,6 +4145,7 @@ static const struct file_operations trace_options_core_fops = {
         .open = tracing_open_generic,
         .read = trace_options_core_read,
         .write = trace_options_core_write,
+        .llseek = generic_file_llseek,
 };
 
 struct dentry *trace_create_file(const char *name,
@@ -4308,9 +4335,6 @@ static __init int tracer_init_debugfs(void)
         trace_create_file("dyn_ftrace_total_info", 0444, d_tracer,
                         &ftrace_update_tot_cnt, &tracing_dyn_info_fops);
 #endif
-#ifdef CONFIG_SYSPROF_TRACER
-        init_tracer_sysprof_debugfs(d_tracer);
-#endif
 
         create_trace_options_dir();
 
@@ -4324,7 +4348,7 @@ static int trace_panic_handler(struct notifier_block *this,
                                unsigned long event, void *unused)
 {
         if (ftrace_dump_on_oops)
-                ftrace_dump();
+                ftrace_dump(ftrace_dump_on_oops);
         return NOTIFY_OK;
 }
 
@@ -4341,7 +4365,7 @@ static int trace_die_handler(struct notifier_block *self,
         switch (val) {
         case DIE_OOPS:
                 if (ftrace_dump_on_oops)
-                        ftrace_dump();
+                        ftrace_dump(ftrace_dump_on_oops);
                 break;
         default:
                 break;
@@ -4367,7 +4391,7 @@ static struct notifier_block trace_die_notifier = {
  */
 #define KERN_TRACE              KERN_EMERG
 
-static void
+void
 trace_printk_seq(struct trace_seq *s)
 {
         /* Probably should print a warning here. */
@@ -4382,7 +4406,15 @@ trace_printk_seq(struct trace_seq *s)
         trace_seq_init(s);
 }
 
-static void __ftrace_dump(bool disable_tracing)
+void trace_init_global_iter(struct trace_iterator *iter)
+{
+        iter->tr = &global_trace;
+        iter->trace = current_trace;
+        iter->cpu_file = TRACE_PIPE_ALL_CPU;
+}
+
+static void
+__ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode)
 {
         static arch_spinlock_t ftrace_dump_lock =
                 (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
@@ -4406,8 +4438,10 @@ static void __ftrace_dump(bool disable_tracing)
         if (disable_tracing)
                 ftrace_kill();
 
+        trace_init_global_iter(&iter);
+
         for_each_tracing_cpu(cpu) {
-                atomic_inc(&global_trace.data[cpu]->disabled);
+                atomic_inc(&iter.tr->data[cpu]->disabled);
         }
 
         old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ;
@@ -4415,12 +4449,25 @@ static void __ftrace_dump(bool disable_tracing)
         /* don't look at user memory in panic mode */
         trace_flags &= ~TRACE_ITER_SYM_USEROBJ;
 
-        printk(KERN_TRACE "Dumping ftrace buffer:\n");
-
         /* Simulate the iterator */
         iter.tr = &global_trace;
         iter.trace = current_trace;
-        iter.cpu_file = TRACE_PIPE_ALL_CPU;
+
+        switch (oops_dump_mode) {
+        case DUMP_ALL:
+                iter.cpu_file = TRACE_PIPE_ALL_CPU;
+                break;
+        case DUMP_ORIG:
+                iter.cpu_file = raw_smp_processor_id();
+                break;
+        case DUMP_NONE:
+                goto out_enable;
+        default:
+                printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n");
+                iter.cpu_file = TRACE_PIPE_ALL_CPU;
+        }
+
+        printk(KERN_TRACE "Dumping ftrace buffer:\n");
 
         /*
          * We need to stop all tracing on all CPUS to read the
@@ -4443,7 +4490,7 @@ static void __ftrace_dump(bool disable_tracing)
                 iter.iter_flags |= TRACE_FILE_LAT_FMT;
                 iter.pos = -1;
 
-                if (find_next_entry_inc(&iter) != NULL) {
+                if (trace_find_next_entry_inc(&iter) != NULL) {
                         int ret;
 
                         ret = print_trace_line(&iter);
@@ -4459,12 +4506,13 @@ static void __ftrace_dump(bool disable_tracing)
         else
                 printk(KERN_TRACE "---------------------------------\n");
 
+ out_enable:
         /* Re-enable tracing if requested */
         if (!disable_tracing) {
                 trace_flags |= old_userobj;
 
                 for_each_tracing_cpu(cpu) {
-                        atomic_dec(&global_trace.data[cpu]->disabled);
+                        atomic_dec(&iter.tr->data[cpu]->disabled);
                 }
                 tracing_on();
         }
@@ -4475,9 +4523,9 @@ static void __ftrace_dump(bool disable_tracing)
 }
 
 /* By default: disable tracing after the dump */
-void ftrace_dump(void)
+void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
 {
-        __ftrace_dump(true);
+        __ftrace_dump(true, oops_dump_mode);
 }
 
 __init static int tracer_alloc_buffers(void)
@@ -4513,16 +4561,14 @@ __init static int tracer_alloc_buffers(void)
 
 
 #ifdef CONFIG_TRACER_MAX_TRACE
-        max_tr.buffer = ring_buffer_alloc(ring_buf_size,
-                                             TRACE_BUFFER_FLAGS);
+        max_tr.buffer = ring_buffer_alloc(1, TRACE_BUFFER_FLAGS);
         if (!max_tr.buffer) {
                 printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n");
                 WARN_ON(1);
                 ring_buffer_free(global_trace.buffer);
                 goto out_free_cpumask;
         }
-        max_tr.entries = ring_buffer_size(max_tr.buffer);
-        WARN_ON(max_tr.entries != global_trace.entries);
+        max_tr.entries = 1;
 #endif
 
         /* Allocate the first page for all buffers */
@@ -4535,9 +4581,6 @@ __init static int tracer_alloc_buffers(void)
 
         register_tracer(&nop_trace);
         current_trace = &nop_trace;
-#ifdef CONFIG_BOOT_TRACER
-        register_tracer(&boot_tracer);
-#endif
         /* All seems OK, enable tracing */
         tracing_disabled = 0;