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Merge tag 'trace-v5.16-rc4' of git://git.kernel.org/pub/scm/linux/ker…
…nel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Tracing, ftrace and tracefs fixes: - Have tracefs honor the gid mount option - Have new files in tracefs inherit the parent ownership - Have direct_ops unregister when it has no more functions - Properly clean up the ops when unregistering multi direct ops - Add a sample module to test the multiple direct ops - Fix memory leak in error path of __create_synth_event()" * tag 'trace-v5.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Fix possible memory leak in __create_synth_event() error path ftrace/samples: Add module to test multi direct modify interface ftrace: Add cleanup to unregister_ftrace_direct_multi ftrace: Use direct_ops hash in unregister_ftrace_direct tracefs: Set all files to the same group ownership as the mount option tracefs: Have new files inherit the ownership of their parent
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| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,152 @@ | ||
| // SPDX-License-Identifier: GPL-2.0-only | ||
| #include <linux/module.h> | ||
| #include <linux/kthread.h> | ||
| #include <linux/ftrace.h> | ||
| #include <asm/asm-offsets.h> | ||
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| void my_direct_func1(unsigned long ip) | ||
| { | ||
| trace_printk("my direct func1 ip %lx\n", ip); | ||
| } | ||
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| void my_direct_func2(unsigned long ip) | ||
| { | ||
| trace_printk("my direct func2 ip %lx\n", ip); | ||
| } | ||
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| extern void my_tramp1(void *); | ||
| extern void my_tramp2(void *); | ||
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| #ifdef CONFIG_X86_64 | ||
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| asm ( | ||
| " .pushsection .text, \"ax\", @progbits\n" | ||
| " .type my_tramp1, @function\n" | ||
| " .globl my_tramp1\n" | ||
| " my_tramp1:" | ||
| " pushq %rbp\n" | ||
| " movq %rsp, %rbp\n" | ||
| " pushq %rdi\n" | ||
| " movq 8(%rbp), %rdi\n" | ||
| " call my_direct_func1\n" | ||
| " popq %rdi\n" | ||
| " leave\n" | ||
| " ret\n" | ||
| " .size my_tramp1, .-my_tramp1\n" | ||
| " .type my_tramp2, @function\n" | ||
| "\n" | ||
| " .globl my_tramp2\n" | ||
| " my_tramp2:" | ||
| " pushq %rbp\n" | ||
| " movq %rsp, %rbp\n" | ||
| " pushq %rdi\n" | ||
| " movq 8(%rbp), %rdi\n" | ||
| " call my_direct_func2\n" | ||
| " popq %rdi\n" | ||
| " leave\n" | ||
| " ret\n" | ||
| " .size my_tramp2, .-my_tramp2\n" | ||
| " .popsection\n" | ||
| ); | ||
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| #endif /* CONFIG_X86_64 */ | ||
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| #ifdef CONFIG_S390 | ||
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| asm ( | ||
| " .pushsection .text, \"ax\", @progbits\n" | ||
| " .type my_tramp1, @function\n" | ||
| " .globl my_tramp1\n" | ||
| " my_tramp1:" | ||
| " lgr %r1,%r15\n" | ||
| " stmg %r0,%r5,"__stringify(__SF_GPRS)"(%r15)\n" | ||
| " stg %r14,"__stringify(__SF_GPRS+8*8)"(%r15)\n" | ||
| " aghi %r15,"__stringify(-STACK_FRAME_OVERHEAD)"\n" | ||
| " stg %r1,"__stringify(__SF_BACKCHAIN)"(%r15)\n" | ||
| " lgr %r2,%r0\n" | ||
| " brasl %r14,my_direct_func1\n" | ||
| " aghi %r15,"__stringify(STACK_FRAME_OVERHEAD)"\n" | ||
| " lmg %r0,%r5,"__stringify(__SF_GPRS)"(%r15)\n" | ||
| " lg %r14,"__stringify(__SF_GPRS+8*8)"(%r15)\n" | ||
| " lgr %r1,%r0\n" | ||
| " br %r1\n" | ||
| " .size my_tramp1, .-my_tramp1\n" | ||
| "\n" | ||
| " .type my_tramp2, @function\n" | ||
| " .globl my_tramp2\n" | ||
| " my_tramp2:" | ||
| " lgr %r1,%r15\n" | ||
| " stmg %r0,%r5,"__stringify(__SF_GPRS)"(%r15)\n" | ||
| " stg %r14,"__stringify(__SF_GPRS+8*8)"(%r15)\n" | ||
| " aghi %r15,"__stringify(-STACK_FRAME_OVERHEAD)"\n" | ||
| " stg %r1,"__stringify(__SF_BACKCHAIN)"(%r15)\n" | ||
| " lgr %r2,%r0\n" | ||
| " brasl %r14,my_direct_func2\n" | ||
| " aghi %r15,"__stringify(STACK_FRAME_OVERHEAD)"\n" | ||
| " lmg %r0,%r5,"__stringify(__SF_GPRS)"(%r15)\n" | ||
| " lg %r14,"__stringify(__SF_GPRS+8*8)"(%r15)\n" | ||
| " lgr %r1,%r0\n" | ||
| " br %r1\n" | ||
| " .size my_tramp2, .-my_tramp2\n" | ||
| " .popsection\n" | ||
| ); | ||
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| #endif /* CONFIG_S390 */ | ||
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| static unsigned long my_tramp = (unsigned long)my_tramp1; | ||
| static unsigned long tramps[2] = { | ||
| (unsigned long)my_tramp1, | ||
| (unsigned long)my_tramp2, | ||
| }; | ||
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| static struct ftrace_ops direct; | ||
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| static int simple_thread(void *arg) | ||
| { | ||
| static int t; | ||
| int ret = 0; | ||
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| while (!kthread_should_stop()) { | ||
| set_current_state(TASK_INTERRUPTIBLE); | ||
| schedule_timeout(2 * HZ); | ||
|
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| if (ret) | ||
| continue; | ||
| t ^= 1; | ||
| ret = modify_ftrace_direct_multi(&direct, tramps[t]); | ||
| if (!ret) | ||
| my_tramp = tramps[t]; | ||
| WARN_ON_ONCE(ret); | ||
| } | ||
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| return 0; | ||
| } | ||
|
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| static struct task_struct *simple_tsk; | ||
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| static int __init ftrace_direct_multi_init(void) | ||
| { | ||
| int ret; | ||
|
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| ftrace_set_filter_ip(&direct, (unsigned long) wake_up_process, 0, 0); | ||
| ftrace_set_filter_ip(&direct, (unsigned long) schedule, 0, 0); | ||
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| ret = register_ftrace_direct_multi(&direct, my_tramp); | ||
|
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| if (!ret) | ||
| simple_tsk = kthread_run(simple_thread, NULL, "event-sample-fn"); | ||
| return ret; | ||
| } | ||
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| static void __exit ftrace_direct_multi_exit(void) | ||
| { | ||
| kthread_stop(simple_tsk); | ||
| unregister_ftrace_direct_multi(&direct, my_tramp); | ||
| } | ||
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| module_init(ftrace_direct_multi_init); | ||
| module_exit(ftrace_direct_multi_exit); | ||
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| MODULE_AUTHOR("Jiri Olsa"); | ||
| MODULE_DESCRIPTION("Example use case of using modify_ftrace_direct_multi()"); | ||
| MODULE_LICENSE("GPL"); |