Re: [PATCH v2 2/9] log: don't build the trace buffer when log is not ready

[Sean Anderson]

On 11/27/20 5:20 AM, Patrick Delaunay wrote:

Update _log function to drop any traces when log is yet initialized:
vsnprintf is no more executed in this case.

This patch allows to reduce the cost for the dropped early debug trace.

Reviewed-by: Simon Glass <s...@chromium.org>
Signed-off-by: Patrick Delaunay <patrick.delau...@st.com>
---

(no changes since v1)

  common/log.c | 13 ++++++++-----
  1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/common/log.c b/common/log.c
index ce39918e04..212789d6b3 100644
--- a/common/log.c
+++ b/common/log.c
@@ -228,6 +228,9 @@ int _log(enum log_category_t cat, enum log_level_t level, 
const char *file,
        struct log_rec rec;
        va_list args;

+ if (!gd)

+               return -ENOSYS;

How early are you expecting this function to get called? AFAIK this will
only return true before board_init_f_init_reserve. Shouldn't functions
that early just not call log in the first place?

--Sean

+
        /* Check for message continuation */
        if (cat == LOGC_CONT)
                cat = gd->logc_prev;
@@ -240,15 +243,15 @@ int _log(enum log_category_t cat, enum log_level_t level, 
const char *file,
        rec.file = file;
        rec.line = line;
        rec.func = func;
+
+       if (!(gd->flags & GD_FLG_LOG_READY)) {
+               gd->log_drop_count++;
+               return -ENOSYS;
+       }
        va_start(args, fmt);
        vsnprintf(buf, sizeof(buf), fmt, args);
        va_end(args);
        rec.msg = buf;
-       if (!gd || !(gd->flags & GD_FLG_LOG_READY)) {
-               if (gd)
-                       gd->log_drop_count++;
-               return -ENOSYS;
-       }
        if (!log_dispatch(&rec)) {
                gd->logc_prev = cat;
                gd->logl_prev = level;