[REFACTOR] create and use get_free_urp_inst()

diff --git a/uprobe/arch/asm-arm/swap_uprobes.c b/uprobe/arch/asm-arm/swap_uprobes.c
index 55801f3..dea907b 100644 (file)
--- a/uprobe/arch/asm-arm/swap_uprobes.c
+++ b/uprobe/arch/asm-arm/swap_uprobes.c
@@ -16,7 +16,6 @@ void gen_insn_execbuf_thumb(void);
 void pc_dep_insn_execbuf_thumb(void);
 int kprobe_trap_handler(struct pt_regs *regs, unsigned int instr);
 void add_rp_inst(struct kretprobe_instance *ri);
-struct kretprobe_instance *get_free_rp_inst (struct kretprobe *rp);
 
 
 #define sign_extend(x, signbit) ((x) | (0 - ((x) & (1 << (signbit)))))

diff --git a/uprobe/swap_uprobes.c b/uprobe/swap_uprobes.c
index a4ac874..962e9f9 100644 (file)
--- a/uprobe/swap_uprobes.c
+++ b/uprobe/swap_uprobes.c
@@ -412,6 +412,54 @@ static void add_urp_inst(struct kretprobe_instance *ri)
        hlist_add_head(&ri->uflist, &ri->rp->used_instances);
 }
 
+#define COMMON_URP_NR 10
+
+static int alloc_nodes_uretprobe(struct kretprobe *rp)
+{
+       int alloc_nodes;
+       struct kretprobe_instance *inst;
+       int i;
+
+#if 1//def CONFIG_PREEMPT
+       rp->maxactive += max(COMMON_URP_NR, 2 * NR_CPUS);
+#else
+       rp->maxacpptive += NR_CPUS;
+#endif
+       alloc_nodes = COMMON_URP_NR;
+
+       for (i = 0; i < alloc_nodes; ++i) {
+               inst = kmalloc(sizeof(*inst), GFP_ATOMIC);
+               if (inst == NULL) {
+                       free_rp_inst(rp);
+                       return -ENOMEM;
+               }
+               INIT_HLIST_NODE(&inst->uflist);
+               hlist_add_head(&inst->uflist, &rp->free_instances);
+       }
+
+       return 0;
+}
+
+/* Called with uretprobe_lock held */
+static struct kretprobe_instance *get_free_urp_inst(struct kretprobe *rp)
+{
+       struct hlist_node *node;
+       struct kretprobe_instance *ri;
+
+       hlist_for_each_entry(ri, node, &rp->free_instances, uflist) {
+               return ri;
+       }
+
+       if (!alloc_nodes_uretprobe(rp)) {
+               hlist_for_each_entry(ri, node, &rp->free_instances, uflist) {
+                       return ri;
+               }
+       }
+
+       return NULL;
+}
+// ===================================================================
+
 int dbi_register_uprobe(struct kprobe *p, struct task_struct *task, int atomic)
 {
        int ret = 0;
@@ -589,7 +637,7 @@ static int pre_handler_uretprobe(struct kprobe *p, struct pt_regs *regs)
        }
 
        /* TODO: test - remove retprobe after func entry but before its exit */
-       if ((ri = get_free_rp_inst(rp)) != NULL) {
+       if ((ri = get_free_urp_inst(rp)) != NULL) {
                ri->rp = rp;
                ri->rp2 = NULL;
                ri->task = current;