From 8656e7a2fa6afcd8682990f804a2a9674568738f Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Thu, 26 Feb 2009 00:41:38 +0100 Subject: [PATCH] tracing/core: make the per cpu trace files in per cpu directories Impact: restructure the VFS layout of per CPU trace buffers The per cpu trace files are all in a single directory: /debug/tracing/per_cpu. In case of a large number of cpu, the content of this directory becomes messy so we create now one directory per cpu inside /debug/tracing/per_cpu which contain each their own trace_pipe and trace files. Ie: /debug/tracing$ ls -R per_cpu per_cpu: cpu0 cpu1 per_cpu/cpu0: trace trace_pipe per_cpu/cpu1: trace trace_pipe Signed-off-by: Frederic Weisbecker Cc: Steven Rostedt Cc: Arnaldo Carvalho de Melo Cc: Peter Zijlstra Cc: Lai Jiangshan Signed-off-by: Ingo Molnar --- kernel/trace/trace.c | 25 ++++++++++++++----------- 1 file changed, 14 insertions(+), 11 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index d8d899f3bd6f..bdaf60d3d337 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3061,28 +3061,31 @@ struct dentry *tracing_dentry_percpu(void) static void tracing_init_debugfs_percpu(long cpu) { struct dentry *d_percpu = tracing_dentry_percpu(); - struct dentry *entry; - /* strlen(trace_pipe) + MAX(log10(cpu)) + '\0' */ - char filename[17]; + struct dentry *entry, *d_cpu; + /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ + char cpu_dir[7]; if (cpu > 999 || cpu < 0) return; - /* per cpu trace_pipe */ - sprintf(filename, "trace_pipe%ld", cpu); + sprintf(cpu_dir, "cpu%ld", cpu); + d_cpu = debugfs_create_dir(cpu_dir, d_percpu); + if (!d_cpu) { + pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); + return; + } - entry = debugfs_create_file(filename, 0444, d_percpu, + /* per cpu trace_pipe */ + entry = debugfs_create_file("trace_pipe", 0444, d_cpu, (void *) cpu, &tracing_pipe_fops); if (!entry) - pr_warning("Could not create debugfs '%s' entry\n", filename); + pr_warning("Could not create debugfs 'trace_pipe' entry\n"); /* per cpu trace */ - sprintf(filename, "trace%ld", cpu); - - entry = debugfs_create_file(filename, 0444, d_percpu, + entry = debugfs_create_file("trace", 0444, d_cpu, (void *) cpu, &tracing_fops); if (!entry) - pr_warning("Could not create debugfs '%s' entry\n", filename); + pr_warning("Could not create debugfs 'trace' entry\n"); } #ifdef CONFIG_FTRACE_SELFTEST