From 2961bf345fd1b736c3db46cad0f69855f67fbe9c Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Wed, 24 Jun 2009 09:53:26 +0800 Subject: trace_stat: Don't increment @pos in seq start() It's wrong to increment @pos in stat_seq_start(). It causes some stat entries lost when reading stat file, if the output of the file is larger than PAGE_SIZE. Reviewed-by: Liming Wang Signed-off-by: Li Zefan Cc: Steven Rostedt Cc: Frederic Weisbecker LKML-Reference: <4A418716.90209@cn.fujitsu.com> Signed-off-by: Ingo Molnar --- kernel/trace/trace_stat.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) (limited to 'kernel/trace/trace_stat.c') diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c index c00643733f4c..e66f5e493342 100644 --- a/kernel/trace/trace_stat.c +++ b/kernel/trace/trace_stat.c @@ -199,17 +199,13 @@ static void *stat_seq_start(struct seq_file *s, loff_t *pos) mutex_lock(&session->stat_mutex); /* If we are in the beginning of the file, print the headers */ - if (!*pos && session->ts->stat_headers) { - (*pos)++; + if (!*pos && session->ts->stat_headers) return SEQ_START_TOKEN; - } node = rb_first(&session->stat_root); for (i = 0; node && i < *pos; i++) node = rb_next(node); - (*pos)++; - return node; } -- cgit v1.2.3 From d8ea37d5de58d35a39d0b4e7d209751aaa1b8174 Mon Sep 17 00:00:00 2001 From: Lai Jiangshan Date: Mon, 6 Jul 2009 16:10:18 +0800 Subject: tracing/stat: Add stat_release() callback Add stat_release() callback to struct tracer_stat, so a stat tracer can release it's entries after the stat file has been read out. Signed-off-by: Lai Jiangshan Signed-off-by: Li Zefan Cc: Lai Jiangshan Cc: Steven Rostedt Cc: Frederic Weisbecker LKML-Reference: <4A51B16A.6020708@cn.fujitsu.com> Signed-off-by: Ingo Molnar --- kernel/trace/trace_stat.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'kernel/trace/trace_stat.c') diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c index e66f5e493342..f069461f10bd 100644 --- a/kernel/trace/trace_stat.c +++ b/kernel/trace/trace_stat.c @@ -49,7 +49,8 @@ static struct dentry *stat_dir; * but it will at least advance closer to the next one * to be released. */ -static struct rb_node *release_next(struct rb_node *node) +static struct rb_node *release_next(struct tracer_stat *ts, + struct rb_node *node) { struct stat_node *snode; struct rb_node *parent = rb_parent(node); @@ -67,6 +68,8 @@ static struct rb_node *release_next(struct rb_node *node) parent->rb_right = NULL; snode = container_of(node, struct stat_node, node); + if (ts->stat_release) + ts->stat_release(snode->stat); kfree(snode); return parent; @@ -78,7 +81,7 @@ static void reset_stat_session(struct stat_session *session) struct rb_node *node = session->stat_root.rb_node; while (node) - node = release_next(node); + node = release_next(session->ts, node); session->stat_root = RB_ROOT; } -- cgit v1.2.3 From 636eacee3b0c76915151db37203cc624becb6d7b Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Thu, 23 Jul 2009 11:29:47 +0800 Subject: tracing/stat: Fix seqfile memory leak Every time we cat a trace_stat file, we leak memory allocated by seq_open(). Also fix memory leak in a failure path in tracing_stat_open(). Signed-off-by: Li Zefan LKML-Reference: <4A67D92B.4060704@cn.fujitsu.com> Signed-off-by: Steven Rostedt --- kernel/trace/trace_stat.c | 34 ++++++++++++++++++++++------------ 1 file changed, 22 insertions(+), 12 deletions(-) (limited to 'kernel/trace/trace_stat.c') diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c index e66f5e493342..aea321c82fa0 100644 --- a/kernel/trace/trace_stat.c +++ b/kernel/trace/trace_stat.c @@ -73,7 +73,7 @@ static struct rb_node *release_next(struct rb_node *node) } } -static void reset_stat_session(struct stat_session *session) +static void __reset_stat_session(struct stat_session *session) { struct rb_node *node = session->stat_root.rb_node; @@ -83,10 +83,17 @@ static void reset_stat_session(struct stat_session *session) session->stat_root = RB_ROOT; } +static void reset_stat_session(struct stat_session *session) +{ + mutex_lock(&session->stat_mutex); + __reset_stat_session(session); + mutex_unlock(&session->stat_mutex); +} + static void destroy_session(struct stat_session *session) { debugfs_remove(session->file); - reset_stat_session(session); + __reset_stat_session(session); mutex_destroy(&session->stat_mutex); kfree(session); } @@ -150,7 +157,7 @@ static int stat_seq_init(struct stat_session *session) int i; mutex_lock(&session->stat_mutex); - reset_stat_session(session); + __reset_stat_session(session); if (!ts->stat_cmp) ts->stat_cmp = dummy_cmp; @@ -183,7 +190,7 @@ exit: return ret; exit_free_rbtree: - reset_stat_session(session); + __reset_stat_session(session); mutex_unlock(&session->stat_mutex); return ret; } @@ -250,16 +257,21 @@ static const struct seq_operations trace_stat_seq_ops = { static int tracing_stat_open(struct inode *inode, struct file *file) { int ret; - + struct seq_file *m; struct stat_session *session = inode->i_private; + ret = stat_seq_init(session); + if (ret) + return ret; + ret = seq_open(file, &trace_stat_seq_ops); - if (!ret) { - struct seq_file *m = file->private_data; - m->private = session; - ret = stat_seq_init(session); + if (ret) { + reset_stat_session(session); + return ret; } + m = file->private_data; + m->private = session; return ret; } @@ -270,11 +282,9 @@ static int tracing_stat_release(struct inode *i, struct file *f) { struct stat_session *session = i->i_private; - mutex_lock(&session->stat_mutex); reset_stat_session(session); - mutex_unlock(&session->stat_mutex); - return 0; + return seq_release(i, f); } static const struct file_operations tracing_stat_fops = { -- cgit v1.2.3 From 97d53202a5670a08b79c8ef2e4fff1c1ee21317c Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Mon, 17 Aug 2009 16:52:53 +0800 Subject: trace_stat: Fix missing entry in stat file One entry is missing in the output of a stat file. The cause is, when stat_seq_start() is called the 2nd time, we should start from the (pos-1)th elem in the rbtree but not pos, because pos == 0 is the header. Signed-off-by: Li Zefan Cc: Steven Rostedt Cc: Frederic Weisbecker LKML-Reference: <4A891A65.70009@cn.fujitsu.com> Signed-off-by: Ingo Molnar --- kernel/trace/trace_stat.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'kernel/trace/trace_stat.c') diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c index 07c60b09258f..a4bb239eb987 100644 --- a/kernel/trace/trace_stat.c +++ b/kernel/trace/trace_stat.c @@ -203,17 +203,21 @@ static void *stat_seq_start(struct seq_file *s, loff_t *pos) { struct stat_session *session = s->private; struct rb_node *node; + int n = *pos; int i; /* Prevent from tracer switch or rbtree modification */ mutex_lock(&session->stat_mutex); /* If we are in the beginning of the file, print the headers */ - if (!*pos && session->ts->stat_headers) - return SEQ_START_TOKEN; + if (session->ts->stat_headers) { + if (n == 0) + return SEQ_START_TOKEN; + n--; + } node = rb_first(&session->stat_root); - for (i = 0; node && i < *pos; i++) + for (i = 0; node && i < n; i++) node = rb_next(node); return node; -- cgit v1.2.3