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copied!<p>If you need to save the stack trace and process its elements somehow, <code>save_stack_trace()</code> or <code>dump_trace()</code> might be also an option. These functions are declared in <code><linux/stacktrace.h></code> and <code><asm/stacktrace.h></code>, respectively.</p> <p>It is not as easy to use these as <code>dump_stack()</code> but if you need more flexibility, they may be helpful. </p> <p>Here is how <code>save_stack_trace()</code> can be used (replace <code>HOW_MANY_ENTRIES_TO_STORE</code> with the value that suits your needs, 16-32 is usually more than enough):</p> <pre><code>unsigned long stack_entries[HOW_MANY_ENTRIES_TO_STORE]; struct stack_trace trace = { .nr_entries = 0, .entries = &stack_entries[0], .max_entries = HOW_MANY_ENTRIES_TO_STORE, /* How many "lower entries" to skip. */ .skip = 0 }; save_stack_trace(&trace); </code></pre> <p>Now <code>stack_entries</code> array contains the appropriate call addresses. The number of elements filled is <code>nr_entries</code>.</p> <p>One more thing to point out. If it is desirable not to output the stack entries that belong to the implementation of <code>save_stack_trace()</code>, <code>dump_trace()</code> or <code>dump_stack()</code> themselves (on different systems, the number of such entries may vary), the following trick can be applied if you use <code>save_stack_trace()</code>. You can use <code>__builtin_return_address(0)</code> as an "anchor" entry and process only the entries "not lower" than that.</p>

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