67d4f6e3bf
There's compilation fail reported kernel test robot for W=1 build:
>> samples/ftrace/ftrace-direct-multi.c:8:6: warning: no previous
prototype for function 'my_direct_func' [-Wmissing-prototypes]
void my_direct_func(unsigned long ip)
The inlined assembly is used outside function, so we can't make
my_direct_func static and pass it as asm input argument.
However my_tramp is already extern so I think there's no problem
keeping my_direct_func extern as well and just add its prototype.
Link: https://lkml.kernel.org/r/20211101153907.377668-1-jolsa@kernel.org
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 5fae941b9a ("ftrace/samples: Add multi direct interface test module")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
55 lines
1.2 KiB
C
55 lines
1.2 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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#include <linux/module.h>
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#include <linux/mm.h> /* for handle_mm_fault() */
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#include <linux/ftrace.h>
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#include <linux/sched/stat.h>
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extern void my_direct_func(unsigned long ip);
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void my_direct_func(unsigned long ip)
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{
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trace_printk("ip %lx\n", ip);
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}
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extern void my_tramp(void *);
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asm (
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" .pushsection .text, \"ax\", @progbits\n"
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" .type my_tramp, @function\n"
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" .globl my_tramp\n"
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" my_tramp:"
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" pushq %rbp\n"
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" movq %rsp, %rbp\n"
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" pushq %rdi\n"
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" movq 8(%rbp), %rdi\n"
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" call my_direct_func\n"
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" popq %rdi\n"
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" leave\n"
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" ret\n"
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" .size my_tramp, .-my_tramp\n"
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" .popsection\n"
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);
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static struct ftrace_ops direct;
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static int __init ftrace_direct_multi_init(void)
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{
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ftrace_set_filter_ip(&direct, (unsigned long) wake_up_process, 0, 0);
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ftrace_set_filter_ip(&direct, (unsigned long) schedule, 0, 0);
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return register_ftrace_direct_multi(&direct, (unsigned long) my_tramp);
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}
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static void __exit ftrace_direct_multi_exit(void)
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{
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unregister_ftrace_direct_multi(&direct, (unsigned long) my_tramp);
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}
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module_init(ftrace_direct_multi_init);
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module_exit(ftrace_direct_multi_exit);
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MODULE_AUTHOR("Jiri Olsa");
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MODULE_DESCRIPTION("Example use case of using register_ftrace_direct_multi()");
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MODULE_LICENSE("GPL");
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