d963cd95be
Implement a new debugfs interface for RAS susbsystem. A file named daemon_active is added there accordingly. This file is used to track if user space daemon accesses perf/trace interface or not. One can track which daemon opens it via "lsof /path/to/debugfs/ras/daemon_active". Signed-off-by: Chen, Gong <gong.chen@linux.intel.com> Link: http://lkml.kernel.org/r/1402475691-30045-5-git-send-email-gong.chen@linux.intel.com Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Tony Luck <tony.luck@intel.com>
57 lines
1.1 KiB
C
57 lines
1.1 KiB
C
#include <linux/debugfs.h>
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static struct dentry *ras_debugfs_dir;
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static atomic_t trace_count = ATOMIC_INIT(0);
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int ras_userspace_consumers(void)
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{
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return atomic_read(&trace_count);
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}
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EXPORT_SYMBOL_GPL(ras_userspace_consumers);
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static int trace_show(struct seq_file *m, void *v)
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{
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return atomic_read(&trace_count);
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}
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static int trace_open(struct inode *inode, struct file *file)
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{
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atomic_inc(&trace_count);
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return single_open(file, trace_show, NULL);
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}
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static int trace_release(struct inode *inode, struct file *file)
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{
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atomic_dec(&trace_count);
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return single_release(inode, file);
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}
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static const struct file_operations trace_fops = {
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.open = trace_open,
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.read = seq_read,
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.llseek = seq_lseek,
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.release = trace_release,
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};
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int __init ras_add_daemon_trace(void)
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{
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struct dentry *fentry;
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if (!ras_debugfs_dir)
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return -ENOENT;
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fentry = debugfs_create_file("daemon_active", S_IRUSR, ras_debugfs_dir,
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NULL, &trace_fops);
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if (!fentry)
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return -ENODEV;
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return 0;
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}
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void __init ras_debugfs_init(void)
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{
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ras_debugfs_dir = debugfs_create_dir("ras", NULL);
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}
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