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ftrace: Fix build warning for ops_references_rec() not used

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The change that made IPMODIFY and DIRECT ops work together needed access
to the ops_references_ip() function, which it pulled out of the module
only code. But now if both CONFIG_MODULES and
CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS is not set, we get the below
warning:

    ‘ops_references_rec’ defined but not used.

Since ops_references_rec() only calls ops_references_ip() replace the
usage of ops_references_rec() with ops_references_ip() and encompass the
function with an #ifdef of DIRECT_CALLS || MODULES being defined.

Link: https://lkml.kernel.org/r/20220801084745.1187987-1-wangjingjin1@huawei.com

Fixes: 53cd885bc5 ("ftrace: Allow IPMODIFY and DIRECT ops on the same function")
Signed-off-by: Wang Jingjin <wangjingjin1@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
This commit is contained in:
Wang Jingjin 2022-08-01 16:47:45 +08:00 committed by Steven Rostedt (Google)
parent 1c23f9e627
commit 123d645577
1 changed files with 33 additions and 46 deletions
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79
kernel/trace/ftrace.c
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@ -1861,8 +1861,6 @@ static void ftrace_hash_rec_enable_modify(struct ftrace_ops *ops,
ftrace_hash_rec_update_modify(ops, filter_hash, 1);
}
static bool ops_references_ip(struct ftrace_ops *ops, unsigned long ip);
/*
* Try to update IPMODIFY flag on each ftrace_rec. Return 0 if it is OK
* or no-needed to update, -EBUSY if it detects a conflict of the flag
@ -3118,49 +3116,6 @@ static inline int ops_traces_mod(struct ftrace_ops *ops)
ftrace_hash_empty(ops->func_hash->notrace_hash);
}
/*
* Check if the current ops references the given ip.
*
* If the ops traces all functions, then it was already accounted for.
* If the ops does not trace the current record function, skip it.
* If the ops ignores the function via notrace filter, skip it.
*/
static bool
ops_references_ip(struct ftrace_ops *ops, unsigned long ip)
{
/* If ops isn't enabled, ignore it */
if (!(ops->flags & FTRACE_OPS_FL_ENABLED))
return false;
/* If ops traces all then it includes this function */
if (ops_traces_mod(ops))
return true;
/* The function must be in the filter */
if (!ftrace_hash_empty(ops->func_hash->filter_hash) &&
!__ftrace_lookup_ip(ops->func_hash->filter_hash, ip))
return false;
/* If in notrace hash, we ignore it too */
if (ftrace_lookup_ip(ops->func_hash->notrace_hash, ip))
return false;
return true;
}
/*
* Check if the current ops references the record.
*
* If the ops traces all functions, then it was already accounted for.
* If the ops does not trace the current record function, skip it.
* If the ops ignores the function via notrace filter, skip it.
*/
static bool
ops_references_rec(struct ftrace_ops *ops, struct dyn_ftrace *rec)
{
return ops_references_ip(ops, rec->ip);
}
static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs)
{
bool init_nop = ftrace_need_init_nop();
@ -6822,6 +6777,38 @@ static int ftrace_get_trampoline_kallsym(unsigned int symnum,
return -ERANGE;
}
#if defined(CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS) || defined(CONFIG_MODULES)
/*
* Check if the current ops references the given ip.
*
* If the ops traces all functions, then it was already accounted for.
* If the ops does not trace the current record function, skip it.
* If the ops ignores the function via notrace filter, skip it.
*/
static bool
ops_references_ip(struct ftrace_ops *ops, unsigned long ip)
{
/* If ops isn't enabled, ignore it */
if (!(ops->flags & FTRACE_OPS_FL_ENABLED))
return false;
/* If ops traces all then it includes this function */
if (ops_traces_mod(ops))
return true;
/* The function must be in the filter */
if (!ftrace_hash_empty(ops->func_hash->filter_hash) &&
!__ftrace_lookup_ip(ops->func_hash->filter_hash, ip))
return false;
/* If in notrace hash, we ignore it too */
if (ftrace_lookup_ip(ops->func_hash->notrace_hash, ip))
return false;
return true;
}
#endif
#ifdef CONFIG_MODULES
#define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next)
@ -6834,7 +6821,7 @@ static int referenced_filters(struct dyn_ftrace *rec)
int cnt = 0;
for (ops = ftrace_ops_list; ops != &ftrace_list_end; ops = ops->next) {
if (ops_references_rec(ops, rec)) {
if (ops_references_ip(ops, rec->ip)) {
if (WARN_ON_ONCE(ops->flags & FTRACE_OPS_FL_DIRECT))
continue;
if (WARN_ON_ONCE(ops->flags & FTRACE_OPS_FL_IPMODIFY))