Adding register_ftrace_direct_ips function that llows
to register array of ip addresses and trampolines
for direct filter. the interface is:
int register_ftrace_direct_ips(unsigned long *ips,
unsigned long *addrs,
int count);
It wil be used in following patches to register bpf
trampolines in batch mode.
Signed-off-by: Jiri Olsa <jo...@kernel.org>
---
include/linux/ftrace.h | 2 ++
kernel/trace/ftrace.c | 75 ++++++++++++++++++++++++++++++++++++++++++
2 files changed, 77 insertions(+)
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index d71d88d10517..9ed52755667a 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -291,6 +291,8 @@ int ftrace_modify_direct_caller(struct ftrace_func_entry
*entry,
unsigned long old_addr,
unsigned long new_addr);
unsigned long ftrace_find_rec_direct(unsigned long ip);
+int register_ftrace_direct_ips(unsigned long *ips, unsigned long *addrs,
+ int count);
#else
# define ftrace_direct_func_count 0
static inline int register_ftrace_direct(unsigned long ip, unsigned long addr)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 44c2d21b8c19..770bcd1a245a 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -5231,6 +5231,81 @@ int register_ftrace_direct(unsigned long ip, unsigned
long addr)
}
EXPORT_SYMBOL_GPL(register_ftrace_direct);
+int register_ftrace_direct_ips(unsigned long *ips, unsigned long *addrs,
+ int count)
+{
+ struct ftrace_hash *free_hash = NULL;
+ struct ftrace_direct_func *direct;
+ struct ftrace_func_entry *entry;
+ int i, j;
+ int ret;
+
+ mutex_lock(&direct_mutex);
+
+ /* Check all the ips */
+ for (i = 0; i < count; i++) {
+ ret = check_direct_ip(ips[i]);
+ if (ret)
+ goto out_unlock;
+ }
+
+ ret = -ENOMEM;
+ if (adjust_direct_size(direct_functions->count + count, &free_hash))
+ goto out_unlock;
+
+ for (i = 0; i < count; i++) {
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ goto out_clean;
+
+ direct = get_direct_func(addrs[i]);
+ if (!direct) {
+ kfree(entry);
+ goto out_clean;
+ }
+
+ direct->count++;
+ entry->ip = ips[i];
+ entry->direct = addrs[i];
+ __add_hash_entry(direct_functions, entry);
+ }
+
+ ret = ftrace_set_filter_ips(&direct_ops, ips, count, 0);
+
+ if (!ret && !(direct_ops.flags & FTRACE_OPS_FL_ENABLED)) {
+ ret = register_ftrace_function(&direct_ops);
+ if (ret)
+ ftrace_set_filter_ips(&direct_ops, ips, count, 1);
+ }
+
+ out_clean:
+ if (ret) {
+ for (j = 0; j < i; j++) {
+ direct = get_direct_func(addrs[j]);
+ if (!direct)
+ continue;
+
+ if (!direct->count)
+ put_direct_func(direct);
+
+ entry = ftrace_lookup_ip(direct_functions, ips[j]);
+ if (WARN_ON_ONCE(!entry))
+ continue;
+ free_hash_entry(direct_functions, entry);
+ }
+ }
+ out_unlock:
+ mutex_unlock(&direct_mutex);
+
+ if (free_hash) {
+ synchronize_rcu_tasks();
+ free_ftrace_hash(free_hash);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(register_ftrace_direct_ips);
+
static struct ftrace_func_entry *find_direct_entry(unsigned long *ip,
struct dyn_ftrace **recp)
{
--
2.26.2
