From a32c7765e2796395aec49f699bd25c407155e9c5 Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Fri, 26 Jun 2009 16:55:51 +0800 Subject: tracing: Fix stack tracer sysctl handling This made my machine completely frozen: # echo 1 > /proc/sys/kernel/stack_tracer_enabled # echo 2 > /proc/sys/kernel/stack_tracer_enabled The cause is register_ftrace_function() was called twice. Also fix ftrace_enabled sysctl, though seems nothing bad happened as I tested it. Signed-off-by: Li Zefan Cc: Steven Rostedt Cc: Frederic Weisbecker LKML-Reference: <4A448D17.9010305@cn.fujitsu.com> Signed-off-by: Ingo Molnar --- kernel/trace/ftrace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel/trace/ftrace.c') diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index f3716bf04df6..bce9e01a29c8 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -3160,10 +3160,10 @@ ftrace_enable_sysctl(struct ctl_table *table, int write, ret = proc_dointvec(table, write, file, buffer, lenp, ppos); - if (ret || !write || (last_ftrace_enabled == ftrace_enabled)) + if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) goto out; - last_ftrace_enabled = ftrace_enabled; + last_ftrace_enabled = !!ftrace_enabled; if (ftrace_enabled) { -- cgit v1.2.2 From 6ab5d668b131d3c5416f6df1d3ca95b82d4fe8a2 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 4 Jun 2009 00:55:45 -0400 Subject: tracing/function-profiler: do not free per cpu variable stat The per cpu variable stat is freeded if we fail to allocate a name on start up. This was due to stat at first being allocated in the initial design. But since then, it has become a static per cpu variable but the free on error was not removed. Also added __init annotation to the function that this is in. [ Impact: prevent possible memory corruption on low mem at boot up ] Signed-off-by: Steven Rostedt Signed-off-by: Ingo Molnar --- kernel/trace/ftrace.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'kernel/trace/ftrace.c') diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index bce9e01a29c8..4521c77d1a1a 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -768,7 +768,7 @@ static struct tracer_stat function_stats __initdata = { .stat_show = function_stat_show }; -static void ftrace_profile_debugfs(struct dentry *d_tracer) +static __init void ftrace_profile_debugfs(struct dentry *d_tracer) { struct ftrace_profile_stat *stat; struct dentry *entry; @@ -786,7 +786,6 @@ static void ftrace_profile_debugfs(struct dentry *d_tracer) * The files created are permanent, if something happens * we still do not free memory. */ - kfree(stat); WARN(1, "Could not allocate stat file for cpu %d\n", cpu); @@ -813,7 +812,7 @@ static void ftrace_profile_debugfs(struct dentry *d_tracer) } #else /* CONFIG_FUNCTION_PROFILER */ -static void ftrace_profile_debugfs(struct dentry *d_tracer) +static __init void ftrace_profile_debugfs(struct dentry *d_tracer) { } #endif /* CONFIG_FUNCTION_PROFILER */ -- cgit v1.2.2 From 87827111a5538633b18e5c641ced673c4c2bb6ce Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Thu, 23 Jul 2009 11:29:11 +0800 Subject: function-graph: Fix seqfile memory leak Every time we cat set_graph_function, we leak memory allocated by seq_open(). Signed-off-by: Li Zefan LKML-Reference: <4A67D907.2010500@cn.fujitsu.com> Signed-off-by: Steven Rostedt --- kernel/trace/ftrace.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) (limited to 'kernel/trace/ftrace.c') diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 4521c77d1a1a..1f3ec2afa511 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -2595,6 +2595,14 @@ ftrace_graph_open(struct inode *inode, struct file *file) return ret; } +static int +ftrace_graph_release(struct inode *inode, struct file *file) +{ + if (file->f_mode & FMODE_READ) + seq_release(inode, file); + return 0; +} + static int ftrace_set_func(unsigned long *array, int *idx, char *buffer) { @@ -2724,9 +2732,10 @@ ftrace_graph_write(struct file *file, const char __user *ubuf, } static const struct file_operations ftrace_graph_fops = { - .open = ftrace_graph_open, - .read = seq_read, - .write = ftrace_graph_write, + .open = ftrace_graph_open, + .read = seq_read, + .write = ftrace_graph_write, + .release = ftrace_graph_release, }; #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ -- cgit v1.2.2 From 8650ae32ef7045e763825dee6256dde7f331bb85 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 22 Jul 2009 23:29:30 -0400 Subject: tracing: only truncate ftrace files when O_TRUNC is set The current code will truncate the ftrace files contents if O_APPEND is not set and the file is opened in write mode. This is incorrect. It should only truncate the file if O_TRUNC is set. Otherwise if one of these files is opened by a C program with fopen "r+", it will incorrectly truncate the file. Reported-by: Jiri Olsa Signed-off-by: Steven Rostedt --- kernel/trace/ftrace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel/trace/ftrace.c') diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 1f3ec2afa511..1e1d23c26308 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1662,7 +1662,7 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable) mutex_lock(&ftrace_regex_lock); if ((file->f_mode & FMODE_WRITE) && - !(file->f_flags & O_APPEND)) + (file->f_flags & O_TRUNC)) ftrace_filter_reset(enable); if (file->f_mode & FMODE_READ) { @@ -2577,7 +2577,7 @@ ftrace_graph_open(struct inode *inode, struct file *file) mutex_lock(&graph_lock); if ((file->f_mode & FMODE_WRITE) && - !(file->f_flags & O_APPEND)) { + (file->f_flags & O_TRUNC)) { ftrace_graph_count = 0; memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs)); } -- cgit v1.2.2