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786a335fef
commit0daf5cb217upstream. There's another compilation fail (first here [1]) reported by kernel test robot for W=1 clang build: >> samples/ftrace/ftrace-direct-multi-modify.c:7:6: warning: no previous prototype for function 'my_direct_func1' [-Wmissing-prototypes] void my_direct_func1(unsigned long ip) Direct functions in ftrace direct sample modules need to have prototypes defined. They are already global in order to be visible for the inline assembly, so there's no problem. The kernel test robot reported just error for ftrace-direct-multi-modify, but I got same errors also for the rest of the modules touched by this patch. [1]67d4f6e3bfftrace/samples: Add missing prototype for my_direct_func Link: https://lkml.kernel.org/r/20211219135317.212430-1-jolsa@kernel.org Reported-by: kernel test robot <lkp@intel.com> Fixes:e1067a07cf("ftrace/samples: Add module to test multi direct modify interface") Fixes:ae0cc3b7e7("ftrace/samples: Add a sample module that implements modify_ftrace_direct()") Fixes:156473a0ff("ftrace: Add another example of register_ftrace_direct() use case") Fixes:b06457c83a("ftrace: Add sample module that uses register_ftrace_direct()") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
97 lines
1.9 KiB
C
97 lines
1.9 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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#include <linux/module.h>
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#include <linux/kthread.h>
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#include <linux/ftrace.h>
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extern void my_direct_func1(void);
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extern void my_direct_func2(void);
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void my_direct_func1(void)
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{
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trace_printk("my direct func1\n");
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}
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void my_direct_func2(void)
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{
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trace_printk("my direct func2\n");
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}
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extern void my_tramp1(void *);
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extern void my_tramp2(void *);
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static unsigned long my_ip = (unsigned long)schedule;
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asm (
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" .pushsection .text, \"ax\", @progbits\n"
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" .type my_tramp1, @function\n"
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" .globl my_tramp1\n"
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" my_tramp1:"
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" pushq %rbp\n"
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" movq %rsp, %rbp\n"
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" call my_direct_func1\n"
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" leave\n"
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" .size my_tramp1, .-my_tramp1\n"
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" ret\n"
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" .type my_tramp2, @function\n"
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" .globl my_tramp2\n"
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" my_tramp2:"
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" pushq %rbp\n"
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" movq %rsp, %rbp\n"
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" call my_direct_func2\n"
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" leave\n"
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" ret\n"
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" .size my_tramp2, .-my_tramp2\n"
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" .popsection\n"
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);
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static unsigned long my_tramp = (unsigned long)my_tramp1;
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static unsigned long tramps[2] = {
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(unsigned long)my_tramp1,
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(unsigned long)my_tramp2,
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};
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static int simple_thread(void *arg)
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{
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static int t;
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int ret = 0;
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while (!kthread_should_stop()) {
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set_current_state(TASK_INTERRUPTIBLE);
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schedule_timeout(2 * HZ);
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if (ret)
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continue;
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t ^= 1;
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ret = modify_ftrace_direct(my_ip, my_tramp, tramps[t]);
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if (!ret)
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my_tramp = tramps[t];
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WARN_ON_ONCE(ret);
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}
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return 0;
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}
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static struct task_struct *simple_tsk;
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static int __init ftrace_direct_init(void)
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{
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int ret;
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ret = register_ftrace_direct(my_ip, my_tramp);
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if (!ret)
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simple_tsk = kthread_run(simple_thread, NULL, "event-sample-fn");
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return ret;
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}
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static void __exit ftrace_direct_exit(void)
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{
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kthread_stop(simple_tsk);
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unregister_ftrace_direct(my_ip, my_tramp);
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}
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module_init(ftrace_direct_init);
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module_exit(ftrace_direct_exit);
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MODULE_AUTHOR("Steven Rostedt");
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MODULE_DESCRIPTION("Example use case of using modify_ftrace_direct()");
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MODULE_LICENSE("GPL");
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