Since sysfs knobs should generally read-back what was just written (unless theres a good reason to do otherwise), this result (using test_dynamic_debug.ko) is suboptimal: echo L3 > p_level_names cat p_level_names 4 Fix this with a -1 offset in LEVEL_NAMES readback. NOTE: Calling this a BUG is debatable, and the above is slightly inaccurate wrt "read-back"; whats written is a LEVEL_NAME (a string). Whats read back is an integer, giving the 'edge' of the 'low-pass-filter' The actual test looks like: RTT: L4 -> p_level_names : 4 :: DOING: levels 4-1 [ 17.509594] dyndbg: "L4" > p_level_names:0x4 [ 17.510115] dyndbg: apply: 0x1f to: 0xf [ 17.510506] dyndbg: query 0: "class L4 +p" mod:* [ 17.510992] dyndbg: split into words: "class" "L4" "+p" [ 17.511521] dyndbg: op='+' [ 17.511811] dyndbg: flags=0x1 [ 17.512127] dyndbg: *flagsp=0x1 *maskp=0xffffffff [ 17.512604] dyndbg: parsed: func="" file="" module="" format="" lineno=0-0 class=L4 [ 17.513414] dyndbg: applied: func="" file="" module="" format="" lineno=0-0 class=L4 [ 17.514204] dyndbg: processed 1 queries, with 1 matches, 0 errs [ 17.514809] dyndbg: bit_4: 1 matches on class: L4 -> 0x1f [ 17.515355] dyndbg: p_level_names: changed bit-4: "L4" f->1f [ 17.515933] dyndbg: total matches: 1 crap [[ 5 != 4 ]] This -1 adjustment just reports the edge consistently with its input-mapping. Fixes: b9400852c080 (dyndbg: add drm.debug style (drm/parameters/debug) bitmap support) Signed-off-by: Jim Cromie <jim.cromie@xxxxxxxxx> --- lib/dynamic_debug.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 009f2ead09c1..48ca1387a409 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -794,6 +794,8 @@ int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp) return scnprintf(buffer, PAGE_SIZE, "0x%lx\n", *dcp->bits); case DD_CLASS_TYPE_LEVEL_NAMES: + return scnprintf(buffer, PAGE_SIZE, "%d\n", *dcp->lvl - 1); + case DD_CLASS_TYPE_LEVEL_NUM: return scnprintf(buffer, PAGE_SIZE, "%d\n", *dcp->lvl); default: -- 2.38.1
