For now, we will use ftrace for the fprobe if fp->exit_handler not exists and CONFIG_DYNAMIC_FTRACE_WITH_REGS is enabled.
However, CONFIG_DYNAMIC_FTRACE_WITH_REGS is not supported by some arch, such as arm. What we need in the fprobe is the function arguments, so we can use ftrace for fprobe if CONFIG_DYNAMIC_FTRACE_WITH_ARGS is enabled. Therefore, use ftrace if CONFIG_DYNAMIC_FTRACE_WITH_REGS or CONFIG_DYNAMIC_FTRACE_WITH_ARGS enabled. Signed-off-by: Menglong Dong <[email protected]> --- v2: - remove the definition of FPROBE_USE_FTRACE --- kernel/trace/fprobe.c | 30 +++++++++++++++++++----------- 1 file changed, 19 insertions(+), 11 deletions(-) diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c index ecd623eef68b..742ad5a61d46 100644 --- a/kernel/trace/fprobe.c +++ b/kernel/trace/fprobe.c @@ -44,6 +44,7 @@ static struct hlist_head fprobe_table[FPROBE_TABLE_SIZE]; static struct rhltable fprobe_ip_table; static DEFINE_MUTEX(fprobe_mutex); +static struct fgraph_ops fprobe_graph_ops; static u32 fprobe_node_hashfn(const void *data, u32 len, u32 seed) { @@ -254,7 +255,7 @@ static inline int __fprobe_kprobe_handler(unsigned long ip, unsigned long parent return ret; } -#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS +#if defined(CONFIG_DYNAMIC_FTRACE_WITH_ARGS) || defined(CONFIG_DYNAMIC_FTRACE_WITH_REGS) /* ftrace_ops callback, this processes fprobes which have only entry_handler. */ static void fprobe_ftrace_entry(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct ftrace_regs *fregs) @@ -295,7 +296,7 @@ NOKPROBE_SYMBOL(fprobe_ftrace_entry); static struct ftrace_ops fprobe_ftrace_ops = { .func = fprobe_ftrace_entry, - .flags = FTRACE_OPS_FL_SAVE_REGS, + .flags = FTRACE_OPS_FL_SAVE_ARGS, }; static int fprobe_ftrace_active; @@ -335,6 +336,13 @@ static bool fprobe_is_ftrace(struct fprobe *fp) { return !fp->exit_handler; } + +static void fprobe_set_ips(unsigned long *ips, unsigned int cnt, int remove, + int reset) +{ + ftrace_set_filter_ips(&fprobe_graph_ops.ops, ips, cnt, remove, reset); + ftrace_set_filter_ips(&fprobe_ftrace_ops, ips, cnt, remove, reset); +} #else static int fprobe_ftrace_add_ips(unsigned long *addrs, int num) { @@ -349,7 +357,13 @@ static bool fprobe_is_ftrace(struct fprobe *fp) { return false; } -#endif + +static void fprobe_set_ips(unsigned long *ips, unsigned int cnt, int remove, + int reset) +{ + ftrace_set_filter_ips(&fprobe_graph_ops.ops, ips, cnt, remove, reset); +} +#endif /* !CONFIG_DYNAMIC_FTRACE_WITH_ARGS && !CONFIG_DYNAMIC_FTRACE_WITH_REGS */ /* fgraph_ops callback, this processes fprobes which have exit_handler. */ static int fprobe_fgraph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops, @@ -596,14 +610,8 @@ static int fprobe_module_callback(struct notifier_block *nb, } while (node == ERR_PTR(-EAGAIN)); rhashtable_walk_exit(&iter); - if (alist.index > 0) { - ftrace_set_filter_ips(&fprobe_graph_ops.ops, - alist.addrs, alist.index, 1, 0); -#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS - ftrace_set_filter_ips(&fprobe_ftrace_ops, - alist.addrs, alist.index, 1, 0); -#endif - } + if (alist.index > 0) + fprobe_set_ips(alist.addrs, alist.index, 1, 0); mutex_unlock(&fprobe_mutex); kfree(alist.addrs); -- 2.51.2
