Hi Jerome
On Mon, 9 Dec 2024 at 17:32, Jerome Forissier
<jerome.foriss...@linaro.org> wrote:
>
> Implement a "trace clear" command to delete the currently accumulated
> trace data. This comes handy when someone needs to trace a particular
> command. For example:
>
> => trace clear; dhcp; trace pause
> => trace stats
> => trace calls 0x02100000 0x10000000
> => tftpput $profbase $profoffset 192.168.0.16:trace.bin
>
> Signed-off-by: Jerome Forissier <jerome.foriss...@linaro.org>
> ---
> cmd/trace.c | 13 ++++++++++++-
> include/trace.h | 2 ++
> lib/trace.c | 47 +++++++++++++++++++++++++++++++++--------------
> 3 files changed, 47 insertions(+), 15 deletions(-)
>
> diff --git a/cmd/trace.c b/cmd/trace.c
> index 937e6a682ad..e95ac7ca9da 100644
> --- a/cmd/trace.c
> +++ b/cmd/trace.c
> @@ -87,8 +87,18 @@ int do_trace(struct cmd_tbl *cmdtp, int flag, int argc,
> char *const argv[])
> trace_set_enabled(0);
> break;
> case 'c':
> - if (create_call_list(argc, argv))
> + switch (*(cmd + 1)) {
> + case 'a':
> + if (create_call_list(argc, argv))
> + return cmd_usage(cmdtp);
> + break;
> + case 'l':
> + if (trace_clear())
> + return CMD_RET_FAILURE;
> + break;
Instead of this, mind changing the command to trace wipe or something similar?
Then we can have a discrete case for 'w' rather than scanning for a string
Cheers
/Ilias
> + default:
> return cmd_usage(cmdtp);
> + }
> break;
> case 'r':
> trace_set_enabled(1);
> @@ -113,6 +123,7 @@ U_BOOT_CMD(
> "stats - display tracing statistics\n"
> "trace pause - pause tracing\n"
> "trace resume - resume tracing\n"
> + "trace clear - clear traces\n"
> "trace funclist [<addr> <size>] - dump function list into
> buffer\n"
> "trace calls [<addr> <size>] "
> "- dump function call trace into buffer"
> diff --git a/include/trace.h b/include/trace.h
> index 763d6d1255a..782eaae2fc2 100644
> --- a/include/trace.h
> +++ b/include/trace.h
> @@ -100,6 +100,8 @@ void trace_set_enabled(int enabled);
>
> int trace_early_init(void);
>
> +int trace_clear(void);
> +
> /**
> * Init the trace system
> *
> diff --git a/lib/trace.c b/lib/trace.c
> index cabbe47b58a..def9f912c92 100644
> --- a/lib/trace.c
> +++ b/lib/trace.c
> @@ -351,14 +351,8 @@ static int get_func_count(void)
> return gd->mon_len / FUNC_SITE_SIZE;
> }
>
> -/**
> - * trace_init() - initialize the tracing system and enable it
> - *
> - * @buff: Pointer to trace buffer
> - * @buff_size: Size of trace buffer
> - * Return: 0 if ok
> - */
> -int notrace trace_init(void *buff, size_t buff_size)
> +static int notrace trace_init_(void *buff, size_t buff_size, bool copy_early,
> + bool enable)
> {
> int func_count = get_func_count();
> size_t needed;
> @@ -368,7 +362,7 @@ int notrace trace_init(void *buff, size_t buff_size)
> return func_count;
> trace_save_gd();
>
> - if (!was_disabled) {
> + if (copy_early) {
> #ifdef CONFIG_TRACE_EARLY
> ulong used, count;
> char *end;
> @@ -394,9 +388,6 @@ int notrace trace_init(void *buff, size_t buff_size)
> }
> puts("\n");
> memcpy(buff, hdr, used);
> -#else
> - puts("trace: already enabled\n");
> - return -EALREADY;
> #endif
> }
> hdr = (struct trace_hdr *)buff;
> @@ -419,13 +410,41 @@ int notrace trace_init(void *buff, size_t buff_size)
> hdr->ftrace_size = (buff_size - needed) / sizeof(*hdr->ftrace);
> hdr->depth_limit = CONFIG_TRACE_CALL_DEPTH_LIMIT;
>
> - puts("trace: enabled\n");
> - trace_enabled = 1;
> + printf("trace: initialized, %senabled\n", enable ? "" : "not ");
> + trace_enabled = enable;
> trace_inited = 1;
>
> return 0;
> }
>
> +/**
> + * trace_init() - initialize the tracing system and enable it
> + *
> + * @buff: Pointer to trace buffer
> + * @buff_size: Size of trace buffer
> + * Return: 0 if ok
> + */
> +int notrace trace_init(void *buff, size_t buff_size)
> +{
> + /* If traces are enabled already, we may have early traces to copy */
> + return trace_init_(buff, buff_size, trace_enabled, true);
> +}
> +
> +/**
> + * trace_clear() - clear accumulated traced data
> + *
> + * May be called with tracing enabled or disabled.
> + */
> +int notrace trace_clear(void)
> +{
> + bool was_enabled = trace_enabled;
> +
> + if (trace_enabled)
> + trace_enabled = 0;
> + return trace_init_(gd->trace_buff, CONFIG_TRACE_BUFFER_SIZE,
> + false, was_enabled);
> +}
> +
> #ifdef CONFIG_TRACE_EARLY
> /**
> * trace_early_init() - initialize the tracing system for early tracing
> --
> 2.43.0
>
