Re: [trace:ftrace/core 35/39] kernel/trace/trace_boot.c:418:17: warning: this 'if' clause does not guard...

From: Masami Hiramatsu
Date: Tue Aug 31 2021 - 09:15:05 EST


Oops, thanks for the great test bot!
Let me send a fix asap.

Thank you,

On Tue, 31 Aug 2021 20:57:56 +0800
kernel test robot <lkp@xxxxxxxxx> wrote:

> tree: https://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git ftrace/core
> head: 3dc65994e3c1c999be3d991cdc96705e167cb3b1
> commit: 5d4648a0415efc239ffb377bce1d389723eda25d [35/39] tracing/boot: Show correct histogram error command
> config: s390-allyesconfig (attached as .config)
> compiler: s390-linux-gcc (GCC) 11.2.0
> reproduce (this is a W=1 build):
> wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> chmod +x ~/bin/make.cross
> # https://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git/commit/?id=5d4648a0415efc239ffb377bce1d389723eda25d
> git remote add trace https://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git
> git fetch --no-tags trace ftrace/core
> git checkout 5d4648a0415efc239ffb377bce1d389723eda25d
> # save the attached .config to linux build tree
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=s390
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
>
> All warnings (new ones prefixed by >>):
>
> kernel/trace/trace_boot.c: In function 'trace_boot_init_histograms':
> >> kernel/trace/trace_boot.c:418:17: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
> 418 | if (trace_boot_compose_hist_cmd(hnode, buf, size) == 0)
> | ^~
> kernel/trace/trace_boot.c:420:25: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
> 420 | if (trigger_process_regex(file, buf) < 0)
> | ^~
>
>
> vim +/if +418 kernel/trace/trace_boot.c
>
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 395
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 396 static void __init
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 397 trace_boot_init_histograms(struct trace_event_file *file,
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 398 struct xbc_node *hnode, char *buf, size_t size)
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 399 {
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 400 struct xbc_node *node;
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 401 const char *p;
> 5d4648a0415efc Masami Hiramatsu 2021-08-06 402 char *tmp;
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 403
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 404 xbc_node_for_each_subkey(hnode, node) {
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 405 p = xbc_node_get_data(node);
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 406 if (!isdigit(p[0]))
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 407 continue;
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 408 /* All digit started node should be instances. */
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 409 if (trace_boot_compose_hist_cmd(node, buf, size) == 0) {
> 5d4648a0415efc Masami Hiramatsu 2021-08-06 410 tmp = kstrdup(buf, GFP_KERNEL);
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 411 if (trigger_process_regex(file, buf) < 0)
> 5d4648a0415efc Masami Hiramatsu 2021-08-06 412 pr_err("Failed to apply hist trigger: %s\n", tmp);
> 5d4648a0415efc Masami Hiramatsu 2021-08-06 413 kfree(tmp);
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 414 }
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 415 }
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 416
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 417 if (xbc_node_find_child(hnode, "keys")) {
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 @418 if (trace_boot_compose_hist_cmd(hnode, buf, size) == 0)
> 5d4648a0415efc Masami Hiramatsu 2021-08-06 419 tmp = kstrdup(buf, GFP_KERNEL);
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 420 if (trigger_process_regex(file, buf) < 0)
> 5d4648a0415efc Masami Hiramatsu 2021-08-06 421 pr_err("Failed to apply hist trigger: %s\n", tmp);
> 5d4648a0415efc Masami Hiramatsu 2021-08-06 422 kfree(tmp);
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 423 }
> 30cb856e3067e5 Masami Hiramatsu 2021-08-06 424
>
> :::::: The code at line 418 was first introduced by commit
> :::::: 30cb856e3067e5d6ae7b2144e1659145ab7686fd tracing/boot: Support multiple histograms for each event
>
> :::::: TO: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> :::::: CC: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
>
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx


--
Masami Hiramatsu <mhiramat@xxxxxxxxxx>