[PATCH v2 12/29] ktap: add generic object handling code(kernel/trace/ktap/kp_obj.[c|h])

[Jovi Zhangwei <jovi.zhangwei@gmail.com>]

kp_obj.c include some common ktap object operation,
like object dump, object length.
It also include generic memory allocate code.

Exposed functions:
1). kp_malloc/kp_zalloc/kp_free

2). kp_obj_dump/kp_obj_show

3). kp_obj_rawequal

4). kp_obj_len

5). kp_obj_new
        allocate new object, all object is linked in G(ks)->allgc.

6). kp_obj_kstack2str
        convert kernel stack to string.

7). kp_obj_freeall
        free all object, called in kp_vm_exit.

Signed-off-by: Jovi Zhangwei <jovi.zhangwei@gmail.com>
---
 kernel/trace/ktap/kp_obj.c | 281 +++++++++++++++++++++++++++++++++++++++++++++
 kernel/trace/ktap/kp_obj.h |  19 +++
 2 files changed, 300 insertions(+)
 create mode 100644 kernel/trace/ktap/kp_obj.c
 create mode 100644 kernel/trace/ktap/kp_obj.h

diff --git a/kernel/trace/ktap/kp_obj.c b/kernel/trace/ktap/kp_obj.c
new file mode 100644
index 0000000..03e25fc
--- /dev/null
+++ b/kernel/trace/ktap/kp_obj.c
@@ -0,0 +1,281 @@
+/*
+ * kp_obj.c - ktap object generic operation
+ *
+ * This file is part of ktap by Jovi Zhangwei.
+ *
+ * Copyright (C) 2012-2014 Jovi Zhangwei <jovi.zhangwei@gmail.com>.
+ *
+ * Adapted from luajit and lua interpreter.
+ * Copyright (C) 2005-2014 Mike Pall.
+ * Copyright (C) 1994-2008 Lua.org, PUC-Rio.
+ *
+ * ktap is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * ktap is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <linux/stacktrace.h>
+#include <linux/module.h>
+#include <linux/kallsyms.h>
+#include <linux/slab.h>
+#include <uapi/ktap/ktap_types.h>
+#include "kp_obj.h"
+#include "kp_str.h"
+#include "kp_tab.h"
+#include "ktap.h"
+#include "kp_vm.h"
+#include "kp_transport.h"
+
+/* Error message strings. */
+const char *kp_err_allmsg =
+#define ERRDEF(name, msg)       msg "\0"
+#include <uapi/ktap/ktap_errmsg.h>
+;
+
+/* memory allocation flag */
+#define KTAP_ALLOC_FLAGS ((GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN) \
+			 & ~__GFP_WAIT)
+
+void *kp_malloc(ktap_state_t *ks, int size)
+{
+	void *addr;
+
+	addr = kmalloc(size, KTAP_ALLOC_FLAGS);
+	if (unlikely(!addr)) {
+		kp_error(ks, "kmalloc failed\n");
+	}
+	return addr;
+}
+
+void *kp_zalloc(ktap_state_t *ks, int size)
+{
+	void *addr;
+
+	addr = kzalloc(size, KTAP_ALLOC_FLAGS);
+	if (unlikely(!addr))
+		kp_error(ks, "kzalloc failed\n");
+	return addr;
+}
+
+void kp_free(ktap_state_t *ks, void *addr)
+{
+	kfree(addr);
+}
+
+
+void kp_obj_dump(ktap_state_t *ks, const ktap_val_t *v)
+{
+	switch (itype(v)) {
+	case KTAP_TNIL:
+		kp_puts(ks, "NIL");
+		break;
+	case KTAP_TTRUE:
+		kp_printf(ks, "true");
+		break;
+	case KTAP_TFALSE:
+		kp_printf(ks, "false");
+		break;
+	case KTAP_TNUM:
+		kp_printf(ks, "NUM %ld", nvalue(v));
+		break;
+	case KTAP_TLIGHTUD:
+		kp_printf(ks, "LIGHTUD 0x%lx", (unsigned long)pvalue(v));
+		break;
+	case KTAP_TFUNC:
+		kp_printf(ks, "FUNCTION 0x%lx", (unsigned long)fvalue(v));
+		break;
+	case KTAP_TSTR:
+		kp_printf(ks, "STR #%s", svalue(v));
+		break;
+	case KTAP_TTAB:
+		kp_printf(ks, "TABLE 0x%lx", (unsigned long)hvalue(v));
+		break;
+        default:
+		kp_printf(ks, "GCVALUE 0x%lx", (unsigned long)gcvalue(v));
+		break;
+	}
+}
+
+void kp_obj_show(ktap_state_t *ks, const ktap_val_t *v)
+{
+	switch (itype(v)) {
+	case KTAP_TNIL:
+		kp_puts(ks, "nil");
+		break;
+	case KTAP_TTRUE:
+		kp_puts(ks, "true");
+		break;
+	case KTAP_TFALSE:
+		kp_puts(ks, "false");
+		break;
+	case KTAP_TNUM:
+		kp_printf(ks, "%ld", nvalue(v));
+		break;
+	case KTAP_TLIGHTUD:
+		kp_printf(ks, "lightud 0x%lx", (unsigned long)pvalue(v));
+		break;
+	case KTAP_TCFUNC:
+		kp_printf(ks, "cfunction 0x%lx", (unsigned long)fvalue(v));
+		break;
+	case KTAP_TFUNC:
+		kp_printf(ks, "function 0x%lx", (unsigned long)gcvalue(v));
+		break;
+	case KTAP_TSTR:
+		kp_puts(ks, svalue(v));
+		break;
+	case KTAP_TTAB:
+		kp_printf(ks, "table 0x%lx", (unsigned long)hvalue(v));
+		break;
+	case KTAP_TEVENTSTR:
+		/* check event context */
+		if (!ks->current_event) {
+			kp_error(ks,
+			"cannot stringify event str in invalid context\n");
+			return;
+		}
+
+		kp_transport_event_write(ks, ks->current_event);
+		break;
+	case KTAP_TKSTACK:
+		kp_transport_print_kstack(ks, v->val.stack.depth,
+					      v->val.stack.skip);
+		break;
+        default:
+		kp_error(ks, "print unknown value type: %d\n", itype(v));
+		break;
+	}
+}
+
+
+/*
+ * equality of ktap values.
+ */
+int kp_obj_rawequal(const ktap_val_t *t1, const ktap_val_t *t2)
+{
+	switch (itype(t1)) {
+	case KTAP_TNIL:
+	case KTAP_TTRUE:
+	case KTAP_TFALSE:
+		return 1;
+	case KTAP_TNUM:
+		return nvalue(t1) == nvalue(t2);
+	case KTAP_TLIGHTUD:
+		return pvalue(t1) == pvalue(t2);
+	case KTAP_TFUNC:
+		return fvalue(t1) == fvalue(t2);
+	case KTAP_TSTR:
+		return rawtsvalue(t1) == rawtsvalue(t2);
+	case KTAP_TTAB:
+		return hvalue(t1) == hvalue(t2);
+	default:
+		return gcvalue(t1) == gcvalue(t2);
+	}
+
+	return 0;
+}
+
+/*
+ * ktap will not use lua's length operator for table,
+ * also # is not for length operator any more in ktap.
+ */
+int kp_obj_len(ktap_state_t *ks, const ktap_val_t *v)
+{
+	switch(itype(v)) {
+	case KTAP_TTAB:
+		return kp_tab_len(ks, hvalue(v));
+	case KTAP_TSTR:
+		return rawtsvalue(v)->len;
+	default:
+		kp_printf(ks, "cannot get length of type %d\n", v->type);
+		return -1;
+	}
+	return 0;
+}
+
+/* need to protect allgc field? */
+ktap_obj_t *kp_obj_new(ktap_state_t *ks, size_t size)
+{
+	ktap_obj_t *o, **list;
+
+	if (ks != G(ks)->mainthread) {
+		kp_error(ks, "kp_obj_new only can be called in mainthread\n");
+		return NULL;
+	}
+
+	o = kp_malloc(ks, size);
+	if (unlikely(!o))
+		return NULL;
+
+	list = &G(ks)->allgc;
+	gch(o)->nextgc = *list;
+	*list = o;
+
+	return o;
+}
+
+
+/* this function may be time consuming, move out from table set/get? */
+ktap_str_t *kp_obj_kstack2str(ktap_state_t *ks, uint16_t depth, uint16_t skip)
+{
+	struct stack_trace trace;
+	unsigned long *bt;
+	char *btstr, *p;
+	int i;
+
+	bt = kp_this_cpu_print_buffer(ks); /* use print percpu buffer */
+	trace.nr_entries = 0;
+	trace.skip = skip;
+	trace.max_entries = depth;
+	trace.entries = (unsigned long *)(bt + 1);
+	save_stack_trace(&trace);
+
+	/* convert backtrace to string */
+	p = btstr = kp_this_cpu_temp_buffer(ks);
+	for (i = 0; i < trace.nr_entries; i++) {
+		unsigned long addr = trace.entries[i];
+
+		if (addr == ULONG_MAX)
+			break;
+
+		p += sprint_symbol(p, addr);
+		*p++ = '\n';
+        }
+
+	return kp_str_new(ks, btstr, p - btstr);
+}
+
+static void free_gclist(ktap_state_t *ks, ktap_obj_t *o)
+{
+	while (o) {
+		ktap_obj_t *next;
+
+		next = gch(o)->nextgc;
+		switch (gch(o)->gct) {
+		case ~KTAP_TTAB:
+			kp_tab_free(ks, (ktap_tab_t *)o);
+			break;
+		case ~KTAP_TUPVAL:
+			kp_freeupval(ks, (ktap_upval_t *)o);
+			break;
+		default:
+			kp_free(ks, o);
+		}
+		o = next;
+	}
+}
+
+void kp_obj_freeall(ktap_state_t *ks)
+{
+	free_gclist(ks, G(ks)->allgc);
+	G(ks)->allgc = NULL;
+}
+
diff --git a/kernel/trace/ktap/kp_obj.h b/kernel/trace/ktap/kp_obj.h
new file mode 100644
index 0000000..b24aab0
--- /dev/null
+++ b/kernel/trace/ktap/kp_obj.h
@@ -0,0 +1,19 @@
+#ifndef __KTAP_OBJ_H__
+#define __KTAP_OBJ_H__
+
+void *kp_malloc(ktap_state_t *ks, int size);
+void *kp_zalloc(ktap_state_t *ks, int size);
+void kp_free(ktap_state_t *ks, void *addr);
+
+void kp_obj_dump(ktap_state_t *ks, const ktap_val_t *v);
+void kp_obj_show(ktap_state_t *ks, const ktap_val_t *v);
+int kp_obj_len(ktap_state_t *ks, const ktap_val_t *rb);
+ktap_obj_t *kp_obj_new(ktap_state_t *ks, size_t size);
+int kp_obj_rawequal(const ktap_val_t *t1, const ktap_val_t *t2);
+ktap_str_t *kp_obj_kstack2str(ktap_state_t *ks, uint16_t depth, uint16_t skip);
+void kp_obj_freeall(ktap_state_t *ks);
+
+#define kp_obj_equal(o1, o2) \
+	(((o1)->type == (o2)->type) && kp_obj_rawequal(o1, o2))
+
+#endif /* __KTAP_OBJ_H__ */
-- 
1.8.1.4