Merge tag 'trace-v4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "There was some breakage with the changes for jump labels in the 4.11
  merge window:

   - powerpc broke as jump labels uses the two LSB bits as flags in
     initialization.

     A check was added to make sure that all jump label entries were 4
     bytes aligned, but powerpc didn't work that way for modules. Adding
     an alignment in the module linker script appeared to be the best
     solution.

   - Jump labels also added an anonymous union to access those LSB bits
     as a normal long. But because this structure had static
     initialization, it broke older compilers that could not statically
     initialize anonymous unions without brackets.

   - The command line parameter for setting function graph filter broke
     the "EMPTY_HASH" descriptor by modifying it instead of creating a
     new hash to hold the entries.

   - The command line parameter ftrace_graph_max_depth was added to
     allow its setting at boot time. It uses existing code and only the
     command line hook was added.

     This is not really a fix, but as it uses existing code without
     affecting anything else, I added it to this release. It was ready
     before the merge window closed, but I wanted to let it sit in
     linux-next for a couple of days first"

* tag 'trace-v4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace/graph: Add ftrace_graph_max_depth kernel parameter
  tracing: Add #undef to fix compile error
  jump_label: Add comment about initialization order for anonymous unions
  jump_label: Fix anonymous union initialization
  module: set __jump_table alignment to 8
  ftrace/graph: Do not modify the EMPTY_HASH for the function_graph filter
  tracing: Fix code comment for ftrace_ops_get_func()
This commit is contained in:
Linus Torvalds
2017-03-07 09:37:28 -08:00
5 changed files with 36 additions and 7 deletions

View File

@@ -4416,16 +4416,24 @@ static int __init set_graph_notrace_function(char *str)
}
__setup("ftrace_graph_notrace=", set_graph_notrace_function);
static int __init set_graph_max_depth_function(char *str)
{
if (!str)
return 0;
fgraph_max_depth = simple_strtoul(str, NULL, 0);
return 1;
}
__setup("ftrace_graph_max_depth=", set_graph_max_depth_function);
static void __init set_ftrace_early_graph(char *buf, int enable)
{
int ret;
char *func;
struct ftrace_hash *hash;
if (enable)
hash = ftrace_graph_hash;
else
hash = ftrace_graph_notrace_hash;
hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS);
if (WARN_ON(!hash))
return;
while (buf) {
func = strsep(&buf, ",");
@@ -4435,6 +4443,11 @@ static void __init set_ftrace_early_graph(char *buf, int enable)
printk(KERN_DEBUG "ftrace: function %s not "
"traceable\n", func);
}
if (enable)
ftrace_graph_hash = hash;
else
ftrace_graph_notrace_hash = hash;
}
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
@@ -5488,7 +5501,7 @@ static void ftrace_ops_assist_func(unsigned long ip, unsigned long parent_ip,
* Normally the mcount trampoline will call the ops->func, but there
* are times that it should not. For example, if the ops does not
* have its own recursion protection, then it should call the
* ftrace_ops_recurs_func() instead.
* ftrace_ops_assist_func() instead.
*
* Returns the function that the trampoline should call for @ops.
*/