--- /dev/null
+/*
+ * Memory allocator tracing
+ *
+ * Copyright (C) 2008 Eduard - Gabriel Munteanu
+ * Copyright (C) 2008 Pekka Enberg <penberg@cs.helsinki.fi>
+ * Copyright (C) 2008 Frederic Weisbecker <fweisbec@gmail.com>
+ */
+
+#include <linux/dcache.h>
+#include <linux/debugfs.h>
+#include <linux/fs.h>
+#include <linux/seq_file.h>
+#include <trace/kmemtrace.h>
+
+#include "trace.h"
+#include "trace_output.h"
+
+/* Select an alternative, minimalistic output than the original one */
+#define TRACE_KMEM_OPT_MINIMAL 0x1
+
+static struct tracer_opt kmem_opts[] = {
+       /* Default disable the minimalistic output */
+       { TRACER_OPT(kmem_minimalistic, TRACE_KMEM_OPT_MINIMAL) },
+       { }
+};
+
+static struct tracer_flags kmem_tracer_flags = {
+       .val = 0,
+       .opts = kmem_opts
+};
+
+
+static bool kmem_tracing_enabled __read_mostly;
+static struct trace_array *kmemtrace_array;
+
+static int kmem_trace_init(struct trace_array *tr)
+{
+       int cpu;
+       kmemtrace_array = tr;
+
+       for_each_cpu_mask(cpu, cpu_possible_map)
+               tracing_reset(tr, cpu);
+
+       kmem_tracing_enabled = true;
+
+       return 0;
+}
+
+static void kmem_trace_reset(struct trace_array *tr)
+{
+       kmem_tracing_enabled = false;
+}
+
+static void kmemtrace_headers(struct seq_file *s)
+{
+       /* Don't need headers for the original kmemtrace output */
+       if (!(kmem_tracer_flags.val & TRACE_KMEM_OPT_MINIMAL))
+               return;
+
+       seq_printf(s, "#\n");
+       seq_printf(s, "# ALLOC  TYPE  REQ   GIVEN  FLAGS     "
+                       "      POINTER         NODE    CALLER\n");
+       seq_printf(s, "# FREE   |      |     |       |       "
+                       "       |   |            |        |\n");
+       seq_printf(s, "# |\n\n");
+}
+
+/*
+ * The two following functions give the original output from kmemtrace,
+ * or something close to....perhaps they need some missing things
+ */
+static enum print_line_t
+kmemtrace_print_alloc_original(struct trace_iterator *iter,
+                               struct kmemtrace_alloc_entry *entry)
+{
+       struct trace_seq *s = &iter->seq;
+       int ret;
+
+       /* Taken from the old linux/kmemtrace.h */
+       ret = trace_seq_printf(s, "type_id %d call_site %lu ptr %lu "
+         "bytes_req %lu bytes_alloc %lu gfp_flags %lu node %d\n",
+          entry->type_id, entry->call_site, (unsigned long) entry->ptr,
+          (unsigned long) entry->bytes_req, (unsigned long) entry->bytes_alloc,
+          (unsigned long) entry->gfp_flags, entry->node);
+
+       if (!ret)
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t
+kmemtrace_print_free_original(struct trace_iterator *iter,
+                               struct kmemtrace_free_entry *entry)
+{
+       struct trace_seq *s = &iter->seq;
+       int ret;
+
+       /* Taken from the old linux/kmemtrace.h */
+       ret = trace_seq_printf(s, "type_id %d call_site %lu ptr %lu\n",
+          entry->type_id, entry->call_site, (unsigned long) entry->ptr);
+
+       if (!ret)
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       return TRACE_TYPE_HANDLED;
+}
+
+
+/* The two other following provide a more minimalistic output */
+static enum print_line_t
+kmemtrace_print_alloc_compress(struct trace_iterator *iter,
+                                       struct kmemtrace_alloc_entry *entry)
+{
+       struct trace_seq *s = &iter->seq;
+       int ret;
+
+       /* Alloc entry */
+       ret = trace_seq_printf(s, "  +      ");
+       if (!ret)
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       /* Type */
+       switch (entry->type_id) {
+       case KMEMTRACE_TYPE_KMALLOC:
+               ret = trace_seq_printf(s, "K   ");
+               break;
+       case KMEMTRACE_TYPE_CACHE:
+               ret = trace_seq_printf(s, "C   ");
+               break;
+       case KMEMTRACE_TYPE_PAGES:
+               ret = trace_seq_printf(s, "P   ");
+               break;
+       default:
+               ret = trace_seq_printf(s, "?   ");
+       }
+
+       if (!ret)
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       /* Requested */
+       ret = trace_seq_printf(s, "%4d   ", entry->bytes_req);
+       if (!ret)
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       /* Allocated */
+       ret = trace_seq_printf(s, "%4d   ", entry->bytes_alloc);
+       if (!ret)
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       /* Flags
+        * TODO: would be better to see the name of the GFP flag names
+        */
+       ret = trace_seq_printf(s, "%08x   ", entry->gfp_flags);
+       if (!ret)
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       /* Pointer to allocated */
+       ret = trace_seq_printf(s, "0x%tx   ", (ptrdiff_t)entry->ptr);
+       if (!ret)
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       /* Node */
+       ret = trace_seq_printf(s, "%4d   ", entry->node);
+       if (!ret)
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       /* Call site */
+       ret = seq_print_ip_sym(s, entry->call_site, 0);
+       if (!ret)
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       if (!trace_seq_printf(s, "\n"))
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t
+kmemtrace_print_free_compress(struct trace_iterator *iter,
+                               struct kmemtrace_free_entry *entry)
+{
+       struct trace_seq *s = &iter->seq;
+       int ret;
+
+       /* Free entry */
+       ret = trace_seq_printf(s, "  -      ");
+       if (!ret)
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       /* Type */
+       switch (entry->type_id) {
+       case KMEMTRACE_TYPE_KMALLOC:
+               ret = trace_seq_printf(s, "K     ");
+               break;
+       case KMEMTRACE_TYPE_CACHE:
+               ret = trace_seq_printf(s, "C     ");
+               break;
+       case KMEMTRACE_TYPE_PAGES:
+               ret = trace_seq_printf(s, "P     ");
+               break;
+       default:
+               ret = trace_seq_printf(s, "?     ");
+       }
+
+       if (!ret)
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       /* Skip requested/allocated/flags */
+       ret = trace_seq_printf(s, "                       ");
+       if (!ret)
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       /* Pointer to allocated */
+       ret = trace_seq_printf(s, "0x%tx   ", (ptrdiff_t)entry->ptr);
+       if (!ret)
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       /* Skip node */
+       ret = trace_seq_printf(s, "       ");
+       if (!ret)
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       /* Call site */
+       ret = seq_print_ip_sym(s, entry->call_site, 0);
+       if (!ret)
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       if (!trace_seq_printf(s, "\n"))
+               return TRACE_TYPE_PARTIAL_LINE;
+
+       return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t kmemtrace_print_line(struct trace_iterator *iter)
+{
+       struct trace_entry *entry = iter->ent;
+
+       switch (entry->type) {
+       case TRACE_KMEM_ALLOC: {
+               struct kmemtrace_alloc_entry *field;
+               trace_assign_type(field, entry);
+               if (kmem_tracer_flags.val & TRACE_KMEM_OPT_MINIMAL)
+                       return kmemtrace_print_alloc_compress(iter, field);
+               else
+                       return kmemtrace_print_alloc_original(iter, field);
+       }
+
+       case TRACE_KMEM_FREE: {
+               struct kmemtrace_free_entry *field;
+               trace_assign_type(field, entry);
+               if (kmem_tracer_flags.val & TRACE_KMEM_OPT_MINIMAL)
+                       return kmemtrace_print_free_compress(iter, field);
+               else
+                       return kmemtrace_print_free_original(iter, field);
+       }
+
+       default:
+               return TRACE_TYPE_UNHANDLED;
+       }
+}
+
+/* Trace allocations */
+void kmemtrace_mark_alloc_node(enum kmemtrace_type_id type_id,
+                            unsigned long call_site,
+                            const void *ptr,
+                            size_t bytes_req,
+                            size_t bytes_alloc,
+                            gfp_t gfp_flags,
+                            int node)
+{
+       struct ring_buffer_event *event;
+       struct kmemtrace_alloc_entry *entry;
+       struct trace_array *tr = kmemtrace_array;
+       unsigned long irq_flags;
+
+       if (!kmem_tracing_enabled)
+               return;
+
+       event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
+                                        &irq_flags);
+       if (!event)
+               return;
+       entry   = ring_buffer_event_data(event);
+       tracing_generic_entry_update(&entry->ent, 0, 0);
+
+       entry->ent.type = TRACE_KMEM_ALLOC;
+       entry->call_site = call_site;
+       entry->ptr = ptr;
+       entry->bytes_req = bytes_req;
+       entry->bytes_alloc = bytes_alloc;
+       entry->gfp_flags = gfp_flags;
+       entry->node     =       node;
+
+       ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
+
+       trace_wake_up();
+}
+
+void kmemtrace_mark_free(enum kmemtrace_type_id type_id,
+                      unsigned long call_site,
+                      const void *ptr)
+{
+       struct ring_buffer_event *event;
+       struct kmemtrace_free_entry *entry;
+       struct trace_array *tr = kmemtrace_array;
+       unsigned long irq_flags;
+
+       if (!kmem_tracing_enabled)
+               return;
+
+       event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
+                                        &irq_flags);
+       if (!event)
+               return;
+       entry   = ring_buffer_event_data(event);
+       tracing_generic_entry_update(&entry->ent, 0, 0);
+
+       entry->ent.type = TRACE_KMEM_FREE;
+       entry->type_id  = type_id;
+       entry->call_site = call_site;
+       entry->ptr = ptr;
+
+       ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
+
+       trace_wake_up();
+}
+
+static struct tracer kmem_tracer __read_mostly = {
+       .name           = "kmemtrace",
+       .init           = kmem_trace_init,
+       .reset          = kmem_trace_reset,
+       .print_line     = kmemtrace_print_line,
+       .print_header = kmemtrace_headers,
+       .flags          = &kmem_tracer_flags
+};
+
+static int __init init_kmem_tracer(void)
+{
+       return register_tracer(&kmem_tracer);
+}
+
+device_initcall(init_kmem_tracer);