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Viewing changes to kernel/trace/ftrace.c

  • Committer: Package Import Robot
  • Author(s): Alessio Igor Bogani
  • Date: 2011-10-26 11:13:05 UTC
  • Revision ID: package-import@ubuntu.com-20111026111305-04kado7d1u2er2rl
Tags: 3.2.0-16.25
Add new lowlatency kernel flavour

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Lines of Context:
kernel/trace/ftrace.c
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};
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enum {
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        FTRACE_ENABLE_CALLS             = (1 << 0),
 
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        FTRACE_UPDATE_CALLS             = (1 << 0),
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        FTRACE_DISABLE_CALLS            = (1 << 1),
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        FTRACE_UPDATE_TRACE_FUNC        = (1 << 2),
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        FTRACE_START_FUNC_RET           = (1 << 3),
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static int
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__ftrace_replace_code(struct dyn_ftrace *rec, int enable)
 
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__ftrace_replace_code(struct dyn_ftrace *rec, int update)
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{
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        unsigned long ftrace_addr;
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        unsigned long flag = 0UL;
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        ftrace_addr = (unsigned long)FTRACE_ADDR;
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        /*
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         * If we are enabling tracing:
 
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         * If we are updating calls:
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         *
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         *   If the record has a ref count, then we need to enable it
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         *   because someone is using it.
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         *
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         *   Otherwise we make sure its disabled.
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         *
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         * If we are disabling tracing, then disable all records that
 
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         * If we are disabling calls, then disable all records that
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         * are enabled.
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         */
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        if (enable && (rec->flags & ~FTRACE_FL_MASK))
 
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        if (update && (rec->flags & ~FTRACE_FL_MASK))
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                flag = FTRACE_FL_ENABLED;
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        /* If the state of this record hasn't changed, then do nothing */
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        return ftrace_make_nop(NULL, rec, ftrace_addr);
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}
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static void ftrace_replace_code(int enable)
 
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static void ftrace_replace_code(int update)
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{
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        struct dyn_ftrace *rec;
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        struct ftrace_page *pg;
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                if (rec->flags & FTRACE_FL_FREE)
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                        continue;
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                failed = __ftrace_replace_code(rec, enable);
 
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                failed = __ftrace_replace_code(rec, update);
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                if (failed) {
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                        ftrace_bug(failed, rec->ip);
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                        /* Stop processing */
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         */
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        function_trace_stop++;
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        if (*command & FTRACE_ENABLE_CALLS)
 
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        if (*command & FTRACE_UPDATE_CALLS)
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                ftrace_replace_code(1);
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        else if (*command & FTRACE_DISABLE_CALLS)
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                ftrace_replace_code(0);
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                return -ENODEV;
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        ftrace_start_up++;
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        command |= FTRACE_ENABLE_CALLS;
 
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        command |= FTRACE_UPDATE_CALLS;
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        /* ops marked global share the filter hashes */
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        if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
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        if (ops != &global_ops || !global_start_up)
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                ops->flags &= ~FTRACE_OPS_FL_ENABLED;
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        if (!ftrace_start_up)
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                command |= FTRACE_DISABLE_CALLS;
 
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        command |= FTRACE_UPDATE_CALLS;
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        if (saved_ftrace_func != ftrace_trace_function) {
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                saved_ftrace_func = ftrace_trace_function;
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        saved_ftrace_func = NULL;
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        /* ftrace_start_up is true if we want ftrace running */
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        if (ftrace_start_up)
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                ftrace_run_update_code(FTRACE_ENABLE_CALLS);
 
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                ftrace_run_update_code(FTRACE_UPDATE_CALLS);
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}
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static void ftrace_shutdown_sysctl(void)
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        ret = ftrace_hash_move(ops, enable, orig_hash, hash);
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        if (!ret && ops->flags & FTRACE_OPS_FL_ENABLED
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            && ftrace_enabled)
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                ftrace_run_update_code(FTRACE_ENABLE_CALLS);
 
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                ftrace_run_update_code(FTRACE_UPDATE_CALLS);
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        mutex_unlock(&ftrace_lock);
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                                       orig_hash, iter->hash);
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                if (!ret && (iter->ops->flags & FTRACE_OPS_FL_ENABLED)
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                    && ftrace_enabled)
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                        ftrace_run_update_code(FTRACE_ENABLE_CALLS);
 
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                        ftrace_run_update_code(FTRACE_UPDATE_CALLS);
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                mutex_unlock(&ftrace_lock);
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        }