Refactor the split of duties between outer & inner fns. The outer fn was previously just an inline unlikely forward to inner, which did all the work. Now, outer handles +t and +l flags itself, and calls inner only when _DPRINTK_FLAGS_INCL_LOOKUP is needed. No functional change. But it does make the results of the inner-fn more cache-friendly (fewer entries, reused more often): 1- no spurious [TID] or <intr> noise 2- no LINE-number to bloat the cache (avg 9 pr_debugs/fn) 3- only LOOKUP stuff Currently LOOKUPs are descriptor-field refs but could be replaced by accessor functions. This would allow the __dyndbg_sites section to be de-duplicated and reclaimed; currently module, filename fields are ~90% repeated. As the accessors get more expensive, the value of caching part of the prefix goes up. Also change inner-fn to return count of extra chars written to the buffer, and drop "inline" from outer, let the compiler decide. Maybe also change name accordingly. Signed-off-by: Jim Cromie <jim.cromie@xxxxxxxxx> --- fixup whitespace --- lib/dynamic_debug.c | 39 ++++++++++++++++++++++----------------- 1 file changed, 22 insertions(+), 17 deletions(-) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 17eefb35ac96..5825b58043a6 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -777,11 +777,28 @@ static int remaining(int wrote) return 0; } -static char *__dynamic_emit_prefix(const struct _ddebug *desc, char *buf) +static int __dynamic_emit_prefix(const struct _ddebug *desc, char *buf, int pos) +{ + if (desc->flags & _DPRINTK_FLAGS_INCL_MODNAME) + pos += snprintf(buf + pos, remaining(pos), "%s:", + desc->modname); + if (desc->flags & _DPRINTK_FLAGS_INCL_FUNCNAME) + pos += snprintf(buf + pos, remaining(pos), "%s:", + desc->function); + if (desc->flags & _DPRINTK_FLAGS_INCL_SOURCENAME) + pos += snprintf(buf + pos, remaining(pos), "%s:", + trim_prefix(desc->filename)); + return pos; +} + +static char *dynamic_emit_prefix(struct _ddebug *desc, char *buf) { int pos_after_tid; int pos = 0; + if (likely(!(desc->flags & _DPRINTK_FLAGS_INCL_ANY))) + return buf; + if (desc->flags & _DPRINTK_FLAGS_INCL_TID) { if (in_interrupt()) pos += snprintf(buf + pos, remaining(pos), "<intr> "); @@ -790,15 +807,10 @@ static char *__dynamic_emit_prefix(const struct _ddebug *desc, char *buf) task_pid_vnr(current)); } pos_after_tid = pos; - if (desc->flags & _DPRINTK_FLAGS_INCL_MODNAME) - pos += snprintf(buf + pos, remaining(pos), "%s:", - desc->modname); - if (desc->flags & _DPRINTK_FLAGS_INCL_FUNCNAME) - pos += snprintf(buf + pos, remaining(pos), "%s:", - desc->function); - if (desc->flags & _DPRINTK_FLAGS_INCL_SOURCENAME) - pos += snprintf(buf + pos, remaining(pos), "%s:", - trim_prefix(desc->filename)); + + if (unlikely(desc->flags & _DPRINTK_FLAGS_INCL_LOOKUP)) + pos += __dynamic_emit_prefix(desc, buf, pos); + if (desc->flags & _DPRINTK_FLAGS_INCL_LINENO) pos += snprintf(buf + pos, remaining(pos), "%d:", desc->lineno); @@ -810,13 +822,6 @@ static char *__dynamic_emit_prefix(const struct _ddebug *desc, char *buf) return buf; } -static inline char *dynamic_emit_prefix(struct _ddebug *desc, char *buf) -{ - if (unlikely(desc->flags & _DPRINTK_FLAGS_INCL_ANY)) - return __dynamic_emit_prefix(desc, buf); - return buf; -} - void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...) { va_list args; -- 2.41.0