[PATCH 05/19] ftrace: Add ftrace_add_rec_direct function

Jiri Olsa
2021-06-05T11:11:05Z

Factor out the code that adds (ip, addr) tuple to direct_functions
hash in new ftrace_add_rec_direct function. It will be used in
following patches.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
kernel/trace/ftrace.c | 60 ++++++++++++++++++++++++++-----------------
1 file changed, 36 insertions(+), 24 deletions(-)

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 2e8a3fde7104..9e584710f542 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2388,6 +2388,39 @@ unsigned long ftrace_find_rec_direct(unsigned long ip)
return entry->direct;
}

+static struct ftrace_func_entry*
+ftrace_add_rec_direct(unsigned long ip, unsigned long addr,
+ struct ftrace_hash **free_hash)
+{
+ struct ftrace_func_entry *entry;
+
+ if (ftrace_hash_empty(direct_functions) ||
+ direct_functions->count > 2 * (1 << direct_functions->size_bits)) {
+ struct ftrace_hash *new_hash;
+ int size = ftrace_hash_empty(direct_functions) ? 0 :
+ direct_functions->count + 1;
+
+ if (size < 32)
+ size = 32;
+
+ new_hash = dup_hash(direct_functions, size);
+ if (!new_hash)
+ return NULL;
+
+ *free_hash = direct_functions;
+ direct_functions = new_hash;
+ }
+
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ return NULL;
+
+ entry->ip = ip;
+ entry->direct = addr;
+ __add_hash_entry(direct_functions, entry);
+ return entry;
+}
+
static void call_direct_funcs(unsigned long ip, unsigned long pip,
struct ftrace_ops *ops, struct ftrace_regs *fregs)
{
@@ -5105,27 +5138,6 @@ int register_ftrace_direct(unsigned long ip, unsigned long addr)
}

ret = -ENOMEM;
- if (ftrace_hash_empty(direct_functions) ||
- direct_functions->count > 2 * (1 << direct_functions->size_bits)) {
- struct ftrace_hash *new_hash;
- int size = ftrace_hash_empty(direct_functions) ? 0 :
- direct_functions->count + 1;
-
- if (size < 32)
- size = 32;
-
- new_hash = dup_hash(direct_functions, size);
- if (!new_hash)
- goto out_unlock;
-
- free_hash = direct_functions;
- direct_functions = new_hash;
- }
-
- entry = kmalloc(sizeof(*entry), GFP_KERNEL);
- if (!entry)
- goto out_unlock;
-
direct = ftrace_find_direct_func(addr);
if (!direct) {
direct = ftrace_alloc_direct_func(addr);
@@ -5135,9 +5147,9 @@ int register_ftrace_direct(unsigned long ip, unsigned long addr)
}
}

- entry->ip = ip;
- entry->direct = addr;
- __add_hash_entry(direct_functions, entry);
+ entry = ftrace_add_rec_direct(ip, addr, &free_hash);
+ if (!entry)
+ goto out_unlock;

ret = ftrace_set_filter_ip(&direct_ops, ip, 0, 0);
if (ret)
--
2.31.1