linux-stable/lib/test_dynamic_debug.c
Jim Cromie 6ea3bf466a dyndbg: test DECLARE_DYNDBG_CLASSMAP, sysfs nodes
Demonstrate use of DECLARE_DYNDBG_CLASSMAP macro, and expose them as
sysfs-nodes for testing.

For each of the 4 class-map-types:

  - declare a class-map of that type,
  - declare the enum corresponding to those class-names
  - share _base across 0..30 range
  - add a __pr_debug_cls() call for each class-name
  - declare 2 sysnodes for each class-map
    for 'p' flag, and future 'T' flag

These declarations create the following sysfs parameter interface:

  :#> pwd
  /sys/module/test_dynamic_debug/parameters
  :#> ls
  T_disjoint_bits  T_disjoint_names  T_level_names  T_level_num  do_prints
  p_disjoint_bits  p_disjoint_names  p_level_names  p_level_num

NOTES:

The local wrapper macro is an api candidate, but there are already too
many parameters.  OTOH, maybe related enum should be in there too,
since it has _base inter-dependencies.

The T_* params control the (future) T flag on the same class'd
pr_debug callsites as their p* counterparts.  Using them will fail,
until the dyndbg-trace patches are added in.

:#> echo 1 > T_disjoint
[   28.792489] dyndbg: disjoint: 0x1 > test_dynamic_debug.T_D2
[   28.793848] dyndbg: query 0: "class D2_CORE +T" mod:*
[   28.795086] dyndbg: split into words: "class" "D2_CORE" "+T"
[   28.796467] dyndbg: op='+'
[   28.797148] dyndbg: unknown flag 'T'
[   28.798021] dyndbg: flags parse failed
[   28.798947] dyndbg: processed 1 queries, with 0 matches, 1 errs
[   28.800378] dyndbg: bit_0: -22 matches on class: D2_CORE -> 0x1
[   28.801959] dyndbg: test_dynamic_debug.T_D2: updated 0x0 -> 0x1
[   28.803974] dyndbg: total matches: -22

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Link: https://lore.kernel.org/r/20220904214134.408619-22-jim.cromie@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-07 17:04:49 +02:00

165 lines
3.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Kernel module for testing dynamic_debug
*
* Authors:
* Jim Cromie <jim.cromie@gmail.com>
*/
#define pr_fmt(fmt) "test_dd: " fmt
#include <linux/module.h>
/* run tests by reading or writing sysfs node: do_prints */
static void do_prints(void); /* device under test */
static int param_set_do_prints(const char *instr, const struct kernel_param *kp)
{
do_prints();
return 0;
}
static int param_get_do_prints(char *buffer, const struct kernel_param *kp)
{
do_prints();
return scnprintf(buffer, PAGE_SIZE, "did do_prints\n");
}
static const struct kernel_param_ops param_ops_do_prints = {
.set = param_set_do_prints,
.get = param_get_do_prints,
};
module_param_cb(do_prints, &param_ops_do_prints, NULL, 0600);
/*
* Using the CLASSMAP api:
* - classmaps must have corresponding enum
* - enum symbols must match/correlate with class-name strings in the map.
* - base must equal enum's 1st value
* - multiple maps must set their base to share the 0-30 class_id space !!
* (build-bug-on tips welcome)
* Additionally, here:
* - tie together sysname, mapname, bitsname, flagsname
*/
#define DD_SYS_WRAP(_model, _flags) \
static unsigned long bits_##_model; \
static struct ddebug_class_param _flags##_model = { \
.bits = &bits_##_model, \
.flags = #_flags, \
.map = &map_##_model, \
}; \
module_param_cb(_flags##_##_model, &param_ops_dyndbg_classes, &_flags##_model, 0600)
/* numeric input, independent bits */
enum cat_disjoint_bits {
D2_CORE = 0,
D2_DRIVER,
D2_KMS,
D2_PRIME,
D2_ATOMIC,
D2_VBL,
D2_STATE,
D2_LEASE,
D2_DP,
D2_DRMRES };
DECLARE_DYNDBG_CLASSMAP(map_disjoint_bits, DD_CLASS_TYPE_DISJOINT_BITS, 0,
"D2_CORE",
"D2_DRIVER",
"D2_KMS",
"D2_PRIME",
"D2_ATOMIC",
"D2_VBL",
"D2_STATE",
"D2_LEASE",
"D2_DP",
"D2_DRMRES");
DD_SYS_WRAP(disjoint_bits, p);
DD_SYS_WRAP(disjoint_bits, T);
/* symbolic input, independent bits */
enum cat_disjoint_names { LOW = 11, MID, HI };
DECLARE_DYNDBG_CLASSMAP(map_disjoint_names, DD_CLASS_TYPE_DISJOINT_NAMES, 10,
"LOW", "MID", "HI");
DD_SYS_WRAP(disjoint_names, p);
DD_SYS_WRAP(disjoint_names, T);
/* numeric verbosity, V2 > V1 related */
enum cat_level_num { V0 = 14, V1, V2, V3, V4, V5, V6, V7 };
DECLARE_DYNDBG_CLASSMAP(map_level_num, DD_CLASS_TYPE_LEVEL_NUM, 14,
"V0", "V1", "V2", "V3", "V4", "V5", "V6", "V7");
DD_SYS_WRAP(level_num, p);
DD_SYS_WRAP(level_num, T);
/* symbolic verbosity */
enum cat_level_names { L0 = 22, L1, L2, L3, L4, L5, L6, L7 };
DECLARE_DYNDBG_CLASSMAP(map_level_names, DD_CLASS_TYPE_LEVEL_NAMES, 22,
"L0", "L1", "L2", "L3", "L4", "L5", "L6", "L7");
DD_SYS_WRAP(level_names, p);
DD_SYS_WRAP(level_names, T);
/* stand-in for all pr_debug etc */
#define prdbg(SYM) __pr_debug_cls(SYM, #SYM " msg\n")
static void do_cats(void)
{
pr_debug("doing categories\n");
prdbg(LOW);
prdbg(MID);
prdbg(HI);
prdbg(D2_CORE);
prdbg(D2_DRIVER);
prdbg(D2_KMS);
prdbg(D2_PRIME);
prdbg(D2_ATOMIC);
prdbg(D2_VBL);
prdbg(D2_STATE);
prdbg(D2_LEASE);
prdbg(D2_DP);
prdbg(D2_DRMRES);
}
static void do_levels(void)
{
pr_debug("doing levels\n");
prdbg(V1);
prdbg(V2);
prdbg(V3);
prdbg(V4);
prdbg(V5);
prdbg(V6);
prdbg(V7);
prdbg(L1);
prdbg(L2);
prdbg(L3);
prdbg(L4);
prdbg(L5);
prdbg(L6);
prdbg(L7);
}
static void do_prints(void)
{
do_cats();
do_levels();
}
static int __init test_dynamic_debug_init(void)
{
pr_debug("init start\n");
do_prints();
pr_debug("init done\n");
return 0;
}
static void __exit test_dynamic_debug_exit(void)
{
pr_debug("exited\n");
}
module_init(test_dynamic_debug_init);
module_exit(test_dynamic_debug_exit);
MODULE_AUTHOR("Jim Cromie <jim.cromie@gmail.com>");
MODULE_LICENSE("GPL");