Author: zoltan
Date: 2005-09-23 11:32:17 -0400 (Fri, 23 Sep 2005)
New Revision: 50579
Modified:
trunk/mono/mono/metadata/ChangeLog
trunk/mono/mono/metadata/rawbuffer.c
trunk/mono/mono/metadata/rawbuffer.h
Log:
2005-09-23 Zoltan Varga <[EMAIL PROTECTED]>
* rawbuffer.h rawbuffer.c: Add code and APIs to help determine the
number of
page faults caused by the runtime while reading metadata.
Modified: trunk/mono/mono/metadata/ChangeLog
===================================================================
--- trunk/mono/mono/metadata/ChangeLog 2005-09-23 15:31:58 UTC (rev 50578)
+++ trunk/mono/mono/metadata/ChangeLog 2005-09-23 15:32:17 UTC (rev 50579)
@@ -1,3 +1,8 @@
+2005-09-23 Zoltan Varga <[EMAIL PROTECTED]>
+
+ * rawbuffer.h rawbuffer.c: Add code and APIs to help determine the
number of
+ page faults caused by the runtime while reading metadata.
+
2005-09-20 Gonzalo Paniagua Javier <[EMAIL PROTECTED]>
* socket-io.c: the field names were changed 3 months ago and no one
Modified: trunk/mono/mono/metadata/rawbuffer.c
===================================================================
--- trunk/mono/mono/metadata/rawbuffer.c 2005-09-23 15:31:58 UTC (rev
50578)
+++ trunk/mono/mono/metadata/rawbuffer.c 2005-09-23 15:32:17 UTC (rev
50579)
@@ -37,6 +37,8 @@
static GHashTable *mmap_map = NULL;
static size_t alignment = 0;
static CRITICAL_SECTION mmap_mutex;
+static gboolean make_unreadable = FALSE;
+static guint32 n_pagefaults = 0;
static void
get_alignment (void)
@@ -158,7 +160,12 @@
if (mprotect (ptr, end - start, prot | PROT_EXEC) != 0)
g_warning (G_GNUC_PRETTY_FUNCTION
": mprotect failed: %s", g_strerror (errno));
-
+
+ if (make_unreadable) {
+ int res = mprotect (ptr, end - start, 0);
+ g_assert (res == 0);
+ }
+
EnterCriticalSection (&mmap_mutex);
g_hash_table_insert (mmap_map, ptr, GINT_TO_POINTER (size));
LeaveCriticalSection (&mmap_mutex);
@@ -236,3 +243,103 @@
mono_raw_buffer_free_malloc (buffer);
}
+/*
+ * mono_raw_buffer_set_make_unreadable:
+ *
+ * Set whenever to make all mmaped memory unreadable. In conjuction with a
+ * SIGSEGV handler, this is useful to find out which pages the runtime tries
to read.
+ */
+void
+mono_raw_buffer_set_make_unreadable (gboolean unreadable)
+{
+ make_unreadable = unreadable;
+}
+
+typedef struct {
+ gboolean found;
+ void *ptr;
+} FindMapUserData;
+
+static void
+find_map (void *start, guint32 size, gpointer user_data)
+{
+ FindMapUserData *data = (FindMapUserData*)user_data;
+
+ if (!data->found)
+ if (((guint8*)data->ptr >= (guint8*)start) &&
((guint8*)data->ptr < (guint8*)start + size))
+ data->found = TRUE;
+}
+
+/*
+ * mono_raw_buffer_is_pagefault:
+ *
+ * Should be called from a SIGSEGV signal handler to find out whenever @ptr
is
+ * within memory allocated by this module.
+ */
+gboolean
+mono_raw_buffer_is_pagefault (void *ptr)
+{
+ FindMapUserData data;
+
+ if (!make_unreadable)
+ return FALSE;
+
+ data.found = FALSE;
+ data.ptr = ptr;
+
+ EnterCriticalSection (&mmap_mutex);
+ g_hash_table_foreach (mmap_map, (GHFunc)find_map, &data);
+ LeaveCriticalSection (&mmap_mutex);
+
+ return data.found;
+}
+
+/*
+ * mono_raw_buffer_handle_pagefault:
+ *
+ * Handle a pagefault caused by an unreadable page by making it readable
again.
+ */
+void
+mono_raw_buffer_handle_pagefault (void *ptr)
+{
+#ifndef PLATFORM_WIN32
+ guint8* start = (guint8*)ROUND_DOWN (((gssize)ptr), alignment);
+ int res;
+
+ EnterCriticalSection (&mmap_mutex);
+ res = mprotect (start, alignment, PROT_READ);
+ g_assert (res == 0);
+
+ n_pagefaults ++;
+ LeaveCriticalSection (&mmap_mutex);
+#endif
+}
+
+/*
+ * mono_raw_buffer_get_n_pagefaults:
+ *
+ * Return the number of times handle_pagefault is called.
+ */
+guint32
+mono_raw_buffer_get_n_pagefaults (void)
+{
+ return n_pagefaults;
+}
+
+/*
+ * mono_raw_buffer_set_n_pagefaults:
+ *
+ * Reset the value returned by get_n_pagefaults () to @n. Useful for
counting the
+ * number of pagefaults caused by a block of code like this:
+ *
+ * int prev_pagefaults = mono_raw_buffer_get_n_pagefaults ();
+ * mono_raw_buffer_set_n_pagefaults (0);
+ * <CODE>
+ * int new_pagefaults = mono_raw_buffer_get_n_pagefaults ();
+ * mono_raw_buffer_set_n_pagefaults (prev_pagefaults);
+ */
+void
+mono_raw_buffer_set_n_pagefaults (guint32 n)
+{
+ n_pagefaults = n;
+}
Modified: trunk/mono/mono/metadata/rawbuffer.h
===================================================================
--- trunk/mono/mono/metadata/rawbuffer.h 2005-09-23 15:31:58 UTC (rev
50578)
+++ trunk/mono/mono/metadata/rawbuffer.h 2005-09-23 15:32:17 UTC (rev
50579)
@@ -7,4 +7,10 @@
void mono_raw_buffer_update (void *buffer, size_t size);
void mono_raw_buffer_free (void *buffer);
+void mono_raw_buffer_set_make_unreadable (gboolean unreadable);
+gboolean mono_raw_buffer_is_pagefault (void *ptr);
+void mono_raw_buffer_handle_pagefault (void *ptr);
+guint32 mono_raw_buffer_get_n_pagefaults (void);
+void mono_raw_buffer_set_n_pagefaults (guint32 n);
+
#endif /* __MONO_RAWBUFFER_H__ */
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