2023-09-12 04:57:29

by Jim Cromie

[permalink] [raw]
Subject: [PATCH v6 00/22] fix DRM_USE_DYNAMIC_DEBUG regression

This series fixes the regression in DRM_USE_DYNAMIC_DEBUG=y

blame analysis: (all mine)

1. my early test scripts did a lot of 'modprobe $m $*',
with dyndbg=.. and debug=.. args
this obscured the lack of drm.debug -> drivers propagation

2. I broke K&R rule: "define once, refer many times".
the classmaps DECLAREd by the drivers would run on args in 1

The thinko beneath that was imitating the "static struct" in the
definition of DEFINE_DYNAMIC_DEBUG_METADATA. Imitating __drm_debug
export instead broke the mental logjam.

So the patchset splits DECLARE_DYNDBG_CLASSMAP duty in 2: with
DYNDBG_CLASSMAP_DEFINE/_USE, where _DEFINE exports the classmap, so
_USE can reference it. The _USEs are added into a new section:
__dyndbg_class_users.

ddebug_add_module() now also scans class_users at modprobe time,
whence it finds the kernel-param that refs the classmap, and applies
its initialized state to the user/driver.

test-dynamic-debug is extended with a _submod, allowing it to
recapitulate the drm.ddebug -/-> drivers failure scenario.


NOTE: patch-14 does the DECLARE -> _DEFINE/_USE, so it also changes
DRM to follow the API change. That makes it buildable, but crosses 2
trees, which isn't so great. But since the feature is marked BROKEN
at this point, perhaps I should have split them.

Finally 3 DRM patches: drops BROKEN on DRM_USE_DYNAMIC_DEBUG, fixes
drm/Makefile, and wires a bunch more drivers to _USE DRM's
drm_debug_classmap.

You can bang at the test module with:
#!/bin/bash

ddcmd () {
echo $* > /proc/dynamic_debug/control
}
vx () {
echo $1 > /sys/module/dynamic_debug/parameters/verbose
}
ddgrep () {
grep $1 /proc/dynamic_debug/control
}
doprints () {
cat /sys/module/test_dynamic_debug/parameters/do_prints
}

note () {
echo NOTE: $* >&2
$*
}
ddparms () {
note ls -l /sys/module/test_dynamic_debug/parameters/
note cat /sys/module/test_dynamic_debug/parameters/*
}
up () {
modprobe drm debug=0x03 debug_trace=0x1ff
}
dn () {
rmmod drm
}
ddtraceon () {
echo 1 > /sys/kernel/tracing/tracing_on
echo 1 > /sys/kernel/tracing/events/dyndbg/enable
}

# replay drm.debug dependent-module scenario
submod () {
echo MP test_dynamic_debug $1 $2 dyndbg=+pm $3 $4

# extra complexity to avoid passing param=s since theyre explicit inits
if [[ -z $1 ]] ; then
modprobe test_dynamic_debug dyndbg=+pm
elif [[ -z $2 ]] ; then
modprobe test_dynamic_debug dyndbg=+pm \
p_disjoint_bits=${1:-0}
elif [[ -z $3 ]] ; then
# force 3,4 off, undoing DEBUG - declutter
modprobe test_dynamic_debug dyndbg=+pm \
p_disjoint_bits=${1:-0} p_level_num=${2:-0}
# p_disjoint_names=${3:-MID,-LOW,-HI} p_level_names=${4:-L3}
elif [[ -z $4 ]] ; then
modprobe test_dynamic_debug dyndbg=+pm \
p_disjoint_bits=${1:-0} p_level_num=${2:-0}
# p_disjoint_names=${3:-MID}
else
modprobe test_dynamic_debug dyndbg=+pm \
p_disjoint_bits=${1:-0} p_level_num=${2:-0}
# p_disjoint_names=${3:-MID} p_level_names=${4:-L3}
fi

# _submod should pick up kparams
echo MP test_dynamic_debug_submod dyndbg=+pmf
modprobe test_dynamic_debug_submod dyndbg=+pmf
}
unmod () {
rmmod test_dynamic_debug_submod
rmmod test_dynamic_debug
}

# The test:
submod_test () {
unmod
submod $*
sleep 1

note "above submod.s D2_* prdbgs should have printed"
note "because they are enabled here:"
ddgrep _submod

echo 1 > /sys/module/test_dynamic_debug/parameters/do_prints

note submod prdbgs should print here
echo 1 > /sys/module/test_dynamic_debug_submod/parameters/do_prints
}

# old-code: triggered jump-label init panic, fixed by doing
# dyndbg-init in notifier, after jump-label
submod_force () {
unmod
submod $*
sleep 1
# force all classes off, then on
note trigger toggled warning by turning off the supposed enabled prdbgs in submod

echo 0 > /sys/module/test_dynamic_debug/parameters/disjoint_bits
echo 0x2ff > /sys/module/test_dynamic_debug/parameters/disjoint_bits

note now theyre on
doprints
}

setup () {
echo dynbg-verbose-0, clearing kmsg, and running submod_test
vx 0
dmesg -W &
submod_test 7 7
ddcmd class V +mfl
ddcmd class V2 +tmfsl
ddcmd class V3 +mfsl
ddcmd class V4 +mfs
ddcmd class V5 +mf
ddcmd class V6 +m
doprints
}



Jim Cromie (22):
test-dyndbg: fixup CLASSMAP usage error
dyndbg: make ddebug_class_param union members same size
dyndbg: replace classmap list with a vector
dyndbg: ddebug_apply_class_bitmap - add module arg, select on it
dyndbg: split param_set_dyndbg_classes to module/wrapper fns
dyndbg: drop NUM_TYPE_ARRAY
dyndbg: reduce verbose/debug clutter
dyndbg: silence debugs with no-change updates
dyndbg: tighten ddebug_class_name() 1st arg type
dyndbg: tighten fn-sig of ddebug_apply_class_bitmap
dyndbg-API: remove DD_CLASS_TYPE_(DISJOINT|LEVEL)_NAMES and code
dyndbg-API: fix CONFIG_DRM_USE_DYNAMIC_DEBUG regression
dyndbg: add for_each_boxed_vector
dyndbg: refactor ddebug_classparam_clamp_input
dyndbg-API: promote DYNDBG_CLASSMAP_PARAM to API
dyndbg-test: build it with just CONFIG_DYNAMIC_DEBUG_CORE
dyndbg-doc: add classmap info to howto
dyndbg: reserve flag bit _DPRINTK_FLAGS_PREFIX_CACHED
dyndbg: add _DPRINTK_FLAGS_INCL_LOOKUP
drm: use correct ccflags-y spelling
drm-drivers: DRM_CLASSMAP_USE in 2nd batch of drivers, helpers
drm: restore CONFIG_DRM_USE_DYNAMIC_DEBUG un-BROKEN

.../admin-guide/dynamic-debug-howto.rst | 60 ++-
MAINTAINERS | 2 +-
drivers/gpu/drm/Kconfig | 3 +-
drivers/gpu/drm/Makefile | 3 +-
drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 12 +-
drivers/gpu/drm/display/drm_dp_helper.c | 12 +-
drivers/gpu/drm/drm_crtc_helper.c | 12 +-
drivers/gpu/drm/drm_gem_shmem_helper.c | 2 +
drivers/gpu/drm/drm_print.c | 35 +-
drivers/gpu/drm/gud/gud_drv.c | 2 +
drivers/gpu/drm/i915/i915_params.c | 12 +-
drivers/gpu/drm/mgag200/mgag200_drv.c | 2 +
drivers/gpu/drm/nouveau/nouveau_drm.c | 12 +-
drivers/gpu/drm/qxl/qxl_drv.c | 2 +
drivers/gpu/drm/radeon/radeon_drv.c | 2 +
drivers/gpu/drm/udl/udl_main.c | 2 +
drivers/gpu/drm/vkms/vkms_drv.c | 2 +
drivers/gpu/drm/vmwgfx/vmwgfx_drv.c | 2 +
include/asm-generic/vmlinux.lds.h | 1 +
include/drm/drm_print.h | 12 +-
include/linux/dynamic_debug.h | 122 ++++--
kernel/module/main.c | 3 +
lib/Kconfig.debug | 10 +-
lib/Makefile | 4 +-
lib/dynamic_debug.c | 407 +++++++++++-------
lib/test_dynamic_debug.c | 137 +++---
lib/test_dynamic_debug_submod.c | 17 +
27 files changed, 546 insertions(+), 346 deletions(-)
create mode 100644 lib/test_dynamic_debug_submod.c

--
2.41.0


2023-09-12 06:26:46

by Jim Cromie

[permalink] [raw]
Subject: [PATCH v6 02/22] dyndbg: make ddebug_class_param union members same size

struct ddebug_class_param keeps a ref to the state-storage of the
param, make both flavors use the same unsigned long under-type.
ISTM this is simpler and safer.

Signed-off-by: Jim Cromie <[email protected]>
---
include/linux/dynamic_debug.h | 2 +-
lib/dynamic_debug.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h
index 4fcbf4d4fd0a..5231aaf361c4 100644
--- a/include/linux/dynamic_debug.h
+++ b/include/linux/dynamic_debug.h
@@ -124,7 +124,7 @@ struct _ddebug_info {
struct ddebug_class_param {
union {
unsigned long *bits;
- unsigned int *lvl;
+ unsigned long *lvl;
};
char flags[8];
const struct ddebug_class_map *map;
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index fea732db7323..6fee76fcddd1 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -796,7 +796,7 @@ int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp)

case DD_CLASS_TYPE_LEVEL_NAMES:
case DD_CLASS_TYPE_LEVEL_NUM:
- return scnprintf(buffer, PAGE_SIZE, "%d\n", *dcp->lvl);
+ return scnprintf(buffer, PAGE_SIZE, "%ld\n", *dcp->lvl);
default:
return -1;
}
--
2.41.0

2023-09-12 12:33:09

by Jim Cromie

[permalink] [raw]
Subject: [PATCH v6 08/22] dyndbg: silence debugs with no-change updates

check for actual changes before announcing them, declutter logs.

Signed-off-by: Jim Cromie <[email protected]>
---
lib/dynamic_debug.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index f64d55d191ad..05c777dedf27 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -591,7 +591,7 @@ static int ddebug_exec_queries(char *query, const char *modname)
return nfound;
}

-/* apply a new bitmap to the sys-knob's current bit-state */
+/* apply a new class-param setting */
static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp,
unsigned long *new_bits, unsigned long *old_bits,
const char *query_modname)
@@ -602,8 +602,9 @@ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp,
int matches = 0;
int bi, ct;

- v2pr_info("apply bitmap: 0x%lx to: 0x%lx for %s\n", *new_bits, *old_bits,
- query_modname ?: "");
+ if (*new_bits != *old_bits)
+ v2pr_info("apply bitmap: 0x%lx to: 0x%lx for %s\n", *new_bits,
+ *old_bits, query_modname ?: "'*'");

for (bi = 0; bi < map->length; bi++) {
if (test_bit(bi, new_bits) == test_bit(bi, old_bits))
@@ -618,8 +619,9 @@ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp,
v2pr_info("bit_%d: %d matches on class: %s -> 0x%lx\n", bi,
ct, map->class_names[bi], *new_bits);
}
- v2pr_info("applied bitmap: 0x%lx to: 0x%lx for %s\n", *new_bits, *old_bits,
- query_modname ?: "");
+ if (*new_bits != *old_bits)
+ v2pr_info("applied bitmap: 0x%lx to: 0x%lx for %s\n", *new_bits,
+ *old_bits, query_modname ?: "'*'");

return matches;
}
--
2.41.0

2023-09-12 12:36:33

by Jim Cromie

[permalink] [raw]
Subject: [PATCH v6 13/22] dyndbg: add for_each_boxed_vector

Add a for_each iterator to walk a counted vector member in a struct
(ie the box), and use it to replace 8 open-coded loops.

Signed-off-by: Jim Cromie <[email protected]>
---
v5- parens-on-box-force-precedence
---
lib/dynamic_debug.c | 20 +++++++++++---------
1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 018578923897..851e7f9de085 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -158,6 +158,9 @@ static void vpr_info_dq(const struct ddebug_query *query, const char *msg)
_dt->num_class_users); \
})

+#define for_each_boxed_vector(_box, _vec, _len, _ct, _curs) \
+ for (_ct = 0, _curs = (_box)->_vec; _ct < (_box)->_len; _ct++, _curs++)
+
#define __outvar /* filled by callee */
static struct ddebug_class_map *ddebug_find_valid_class(struct ddebug_table const *dt,
const char *class_string,
@@ -167,7 +170,7 @@ static struct ddebug_class_map *ddebug_find_valid_class(struct ddebug_table cons
struct ddebug_class_user *cli;
int i, idx;

- for (i = 0, map = dt->classes; i < dt->num_classes; i++, map++) {
+ for_each_boxed_vector(dt, classes, num_classes, i, map) {
idx = match_string(map->class_names, map->length, class_string);
if (idx >= 0) {
*class_id = idx + map->base;
@@ -175,7 +178,7 @@ static struct ddebug_class_map *ddebug_find_valid_class(struct ddebug_table cons
return map;
}
}
- for (i = 0, cli = dt->class_users; i < dt->num_class_users; i++, cli++) {
+ for_each_boxed_vector(dt, class_users, num_class_users, i, cli) {
idx = match_string(cli->map->class_names, cli->map->length, class_string);
if (idx >= 0) {
*class_id = idx + cli->map->base;
@@ -1058,11 +1061,11 @@ static const char *ddebug_class_name(struct ddebug_table *dt, struct _ddebug *dp
struct ddebug_class_user *cli = dt->class_users;
int i;

- for (i = 0; i < dt->num_classes; i++, map++)
+ for_each_boxed_vector(dt, classes, num_classes, i, map)
if (class_in_range(dp->class_id, map))
return map->class_names[dp->class_id - map->base];

- for (i = 0; i < dt->num_class_users; i++, cli++)
+ for_each_boxed_vector(dt, class_users, num_class_users, i, cli)
if (class_in_range(dp->class_id, cli->map))
return cli->map->class_names[dp->class_id - cli->map->base];

@@ -1216,7 +1219,7 @@ static void ddebug_attach_module_classes(struct ddebug_table *dt, struct _ddebug
struct ddebug_class_map *cm;
int i, nc = 0;

- for (i = 0, cm = di->classes; i < di->num_classes; i++, cm++) {
+ for_each_boxed_vector(di, classes, num_classes, i, cm) {

if (!strcmp(cm->mod_name, dt->mod_name)) {
vpr_cm_info(cm, "classes[%d]:", i);
@@ -1229,7 +1232,7 @@ static void ddebug_attach_module_classes(struct ddebug_table *dt, struct _ddebug
vpr_info("module:%s attached %d classes\n", dt->mod_name, nc);

/* now iterate dt */
- for (i = 0, cm = dt->classes; i < dt->num_classes; i++, cm++)
+ for_each_boxed_vector(di, classes, num_classes, i, cm)
ddebug_apply_params(cm, cm->mod_name);
}

@@ -1249,7 +1252,7 @@ static void ddebug_attach_user_module_classes(struct ddebug_table *dt,
* module's refs, save to dt. For loadables, this is the
* whole array.
*/
- for (i = 0, cli = di->class_users; i < di->num_class_users; i++, cli++) {
+ for_each_boxed_vector(di, class_users, num_class_users, i, cli) {

if (WARN_ON(!cli || !cli->map || !cli->user_mod_name))
continue;
@@ -1264,8 +1267,7 @@ static void ddebug_attach_user_module_classes(struct ddebug_table *dt,
}
dt->num_class_users = nc;

- /* now iterate dt */
- for (i = 0, cli = dt->class_users; i < dt->num_class_users; i++, cli++)
+ for_each_boxed_vector(di, class_users, num_class_users, i, cli)
ddebug_apply_params(cli->map, cli->user_mod_name);

vpr_dt_info(dt, "attach-client-module: ");
--
2.41.0

2023-09-12 15:05:34

by Jim Cromie

[permalink] [raw]
Subject: [PATCH v6 18/22] dyndbg: reserve flag bit _DPRINTK_FLAGS_PREFIX_CACHED

Reserve bit 7 to remember that a pr-debug callsite is/was:
- enabled, with +p
- wants a dynamic-prefix, with one+ of module:function:sourcfile
- was previously called
- was thus saved in the cache. NOT YET.

Its unclear whether any cache fetch would be faster than 2-3 field
fetches, but theres another factor; the 3 columns in the __dyndbg
section are highly redundant and compressible, but to get the
compression, we need field accessors, which will rebalance the
tradeoff.

So, for now, its just the bit reservation.

Signed-off-by: Jim Cromie <[email protected]>
---
include/linux/dynamic_debug.h | 1 +
1 file changed, 1 insertion(+)

diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h
index 15edac27cb56..bdb0d12b13ec 100644
--- a/include/linux/dynamic_debug.h
+++ b/include/linux/dynamic_debug.h
@@ -38,6 +38,7 @@ struct _ddebug {
#define _DPRINTK_FLAGS_INCL_LINENO (1<<3)
#define _DPRINTK_FLAGS_INCL_TID (1<<4)
#define _DPRINTK_FLAGS_INCL_SOURCENAME (1<<5)
+#define _DPRINTK_FLAGS_PREFIX_CACHED (1<<7)

#define _DPRINTK_FLAGS_INCL_ANY \
(_DPRINTK_FLAGS_INCL_MODNAME | _DPRINTK_FLAGS_INCL_FUNCNAME |\
--
2.41.0

2023-09-12 19:13:28

by Jim Cromie

[permalink] [raw]
Subject: [PATCH v6 20/22] drm: restore CONFIG_DRM_USE_DYNAMIC_DEBUG un-BROKEN

Lots of burn-in testing needed before signing, upstreaming.

NOTE: I set default Y to maximize testing by default.
Is there a better way to do this ?

Signed-off-by: Jim Cromie <[email protected]>
---
drivers/gpu/drm/Kconfig | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index afb3b2f5f425..27bbb03e84dd 100644
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -52,8 +52,7 @@ config DRM_DEBUG_MM

config DRM_USE_DYNAMIC_DEBUG
bool "use dynamic debug to implement drm.debug"
- default n
- depends on BROKEN
+ default y
depends on DRM
depends on DYNAMIC_DEBUG || DYNAMIC_DEBUG_CORE
depends on JUMP_LABEL
--
2.41.0

2023-09-12 20:16:51

by Jim Cromie

[permalink] [raw]
Subject: [PATCH v6 03/22] dyndbg: replace classmap list with a vector

Classmaps are stored/linked in a section/array, but are each added to
the module's ddebug_table.maps list-head.

This is unnecessary; even when ddebug_attach_classmap() is handling
the builtin section (with classmaps for multiple builtin modules), its
contents are ordered, so a module's possibly multiple classmaps will
be consecutive in the section, and could be treated as a vector/block,
since both start-addy and subrange length are in the ddebug_info arg.

So this changes:

struct ddebug_class_map drops list-head link.

struct ddebug_table drops the list-head maps, and gets: classes &
num_classes for the start-addy and num_classes, placed to improve
struct packing.

The loading: in ddebug_attach_module_classes(), replace the
for-the-modname list-add loop, with a forloop that finds the module's
subrange (start,length) of matching classmaps within the possibly
builtin classmaps vector, and saves those to the ddebug_table.

The reading/using: change list-foreach loops in ddebug_class_name() &
ddebug_find_valid_class() to walk the array from start to length.

Also:
Move #define __outvar up, above an added use in a fn-prototype.
Simplify ddebug_attach_module_classes args, ref has both addy,len.

no functional changes

Signed-off-by: Jim Cromie <[email protected]>
---
include/linux/dynamic_debug.h | 1 -
lib/dynamic_debug.c | 61 ++++++++++++++++++-----------------
2 files changed, 32 insertions(+), 30 deletions(-)

diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h
index 5231aaf361c4..b53217e4b711 100644
--- a/include/linux/dynamic_debug.h
+++ b/include/linux/dynamic_debug.h
@@ -83,7 +83,6 @@ enum class_map_type {
};

struct ddebug_class_map {
- struct list_head link;
struct module *mod;
const char *mod_name; /* needed for builtins */
const char **class_names;
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 6fee76fcddd1..8b46d56f73a5 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -45,10 +45,11 @@ extern struct ddebug_class_map __start___dyndbg_classes[];
extern struct ddebug_class_map __stop___dyndbg_classes[];

struct ddebug_table {
- struct list_head link, maps;
+ struct list_head link;
const char *mod_name;
- unsigned int num_ddebugs;
struct _ddebug *ddebugs;
+ struct ddebug_class_map *classes;
+ unsigned int num_ddebugs, num_classes;
};

struct ddebug_query {
@@ -147,13 +148,15 @@ static void vpr_info_dq(const struct ddebug_query *query, const char *msg)
query->first_lineno, query->last_lineno, query->class_string);
}

+#define __outvar /* filled by callee */
static struct ddebug_class_map *ddebug_find_valid_class(struct ddebug_table const *dt,
- const char *class_string, int *class_id)
+ const char *class_string,
+ __outvar int *class_id)
{
struct ddebug_class_map *map;
- int idx;
+ int i, idx;

- list_for_each_entry(map, &dt->maps, link) {
+ for (map = dt->classes, i = 0; i < dt->num_classes; i++, map++) {
idx = match_string(map->class_names, map->length, class_string);
if (idx >= 0) {
*class_id = idx + map->base;
@@ -164,7 +167,6 @@ static struct ddebug_class_map *ddebug_find_valid_class(struct ddebug_table cons
return NULL;
}

-#define __outvar /* filled by callee */
/*
* Search the tables for _ddebug's which match the given `query' and
* apply the `flags' and `mask' to them. Returns number of matching
@@ -1111,9 +1113,10 @@ static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos)

static const char *ddebug_class_name(struct ddebug_iter *iter, struct _ddebug *dp)
{
- struct ddebug_class_map *map;
+ struct ddebug_class_map *map = iter->table->classes;
+ int i, nc = iter->table->num_classes;

- list_for_each_entry(map, &iter->table->maps, link)
+ for (i = 0; i < nc; i++, map++)
if (class_in_range(dp->class_id, map))
return map->class_names[dp->class_id - map->base];

@@ -1197,30 +1200,31 @@ static const struct proc_ops proc_fops = {
.proc_write = ddebug_proc_write
};

-static void ddebug_attach_module_classes(struct ddebug_table *dt,
- struct ddebug_class_map *classes,
- int num_classes)
+static void ddebug_attach_module_classes(struct ddebug_table *dt, struct _ddebug_info *di)
{
struct ddebug_class_map *cm;
- int i, j, ct = 0;
+ int i, nc = 0;

- for (cm = classes, i = 0; i < num_classes; i++, cm++) {
+ /*
+ * Find this module's classmaps in a subrange/wholerange of
+ * the builtin/modular classmap vector/section. Save the start
+ * and length of the subrange at its edges.
+ */
+ for (cm = di->classes, i = 0; i < di->num_classes; i++, cm++) {

if (!strcmp(cm->mod_name, dt->mod_name)) {
-
- v2pr_info("class[%d]: module:%s base:%d len:%d ty:%d\n", i,
- cm->mod_name, cm->base, cm->length, cm->map_type);
-
- for (j = 0; j < cm->length; j++)
- v3pr_info(" %d: %d %s\n", j + cm->base, j,
- cm->class_names[j]);
-
- list_add(&cm->link, &dt->maps);
- ct++;
+ if (!nc) {
+ v2pr_info("start subrange, class[%d]: module:%s base:%d len:%d ty:%d\n",
+ i, cm->mod_name, cm->base, cm->length, cm->map_type);
+ dt->classes = cm;
+ }
+ nc++;
}
}
- if (ct)
- vpr_info("module:%s attached %d classes\n", dt->mod_name, ct);
+ if (nc) {
+ dt->num_classes = nc;
+ vpr_info("module:%s attached %d classes\n", dt->mod_name, nc);
+ }
}

/*
@@ -1253,10 +1257,9 @@ static int ddebug_add_module(struct _ddebug_info *di, const char *modname)
dt->num_ddebugs = di->num_descs;

INIT_LIST_HEAD(&dt->link);
- INIT_LIST_HEAD(&dt->maps);

if (di->classes && di->num_classes)
- ddebug_attach_module_classes(dt, di->classes, di->num_classes);
+ ddebug_attach_module_classes(dt, di);

mutex_lock(&ddebug_lock);
list_add_tail(&dt->link, &ddebug_tables);
@@ -1369,8 +1372,8 @@ static void ddebug_remove_all_tables(void)
mutex_lock(&ddebug_lock);
while (!list_empty(&ddebug_tables)) {
struct ddebug_table *dt = list_entry(ddebug_tables.next,
- struct ddebug_table,
- link);
+ struct ddebug_table,
+ link);
ddebug_table_free(dt);
}
mutex_unlock(&ddebug_lock);
--
2.41.0

2023-09-12 23:44:02

by Jim Cromie

[permalink] [raw]
Subject: [PATCH v6 10/22] dyndbg: tighten fn-sig of ddebug_apply_class_bitmap

old_bits arg is currently a pointer to the input bits, but this could
allow inadvertent changes to the input by the fn. Disallow this.
And constify new_bits while here.

Signed-off-by: Jim Cromie <[email protected]>
---
lib/dynamic_debug.c | 21 +++++++++++----------
1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index e8bade6c6c06..13cab20029e6 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -593,7 +593,8 @@ static int ddebug_exec_queries(char *query, const char *modname)

/* apply a new class-param setting */
static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp,
- unsigned long *new_bits, unsigned long *old_bits,
+ const unsigned long *new_bits,
+ const unsigned long old_bits,
const char *query_modname)
{
#define QUERY_SIZE 128
@@ -602,12 +603,12 @@ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp,
int matches = 0;
int bi, ct;

- if (*new_bits != *old_bits)
+ if (*new_bits != old_bits)
v2pr_info("apply bitmap: 0x%lx to: 0x%lx for %s\n", *new_bits,
- *old_bits, query_modname ?: "'*'");
+ old_bits, query_modname ?: "'*'");

for (bi = 0; bi < map->length; bi++) {
- if (test_bit(bi, new_bits) == test_bit(bi, old_bits))
+ if (test_bit(bi, new_bits) == test_bit(bi, &old_bits))
continue;

snprintf(query, QUERY_SIZE, "class %s %c%s", map->class_names[bi],
@@ -619,9 +620,9 @@ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp,
v2pr_info("bit_%d: %d matches on class: %s -> 0x%lx\n", bi,
ct, map->class_names[bi], *new_bits);
}
- if (*new_bits != *old_bits)
+ if (*new_bits != old_bits)
v2pr_info("applied bitmap: 0x%lx to: 0x%lx for %s\n", *new_bits,
- *old_bits, query_modname ?: "'*'");
+ old_bits, query_modname ?: "'*'");

return matches;
}
@@ -678,7 +679,7 @@ static int param_set_dyndbg_classnames(const char *instr, const struct kernel_pa
continue;
}
curr_bits ^= BIT(cls_id);
- totct += ddebug_apply_class_bitmap(dcp, &curr_bits, dcp->bits, NULL);
+ totct += ddebug_apply_class_bitmap(dcp, &curr_bits, *dcp->bits, NULL);
*dcp->bits = curr_bits;
v2pr_info("%s: changed bit %d:%s\n", KP_NAME(kp), cls_id,
map->class_names[cls_id]);
@@ -688,7 +689,7 @@ static int param_set_dyndbg_classnames(const char *instr, const struct kernel_pa
old_bits = CLASSMAP_BITMASK(*dcp->lvl);
curr_bits = CLASSMAP_BITMASK(cls_id + (wanted ? 1 : 0 ));

- totct += ddebug_apply_class_bitmap(dcp, &curr_bits, &old_bits, NULL);
+ totct += ddebug_apply_class_bitmap(dcp, &curr_bits, old_bits, NULL);
*dcp->lvl = (cls_id + (wanted ? 1 : 0));
v2pr_info("%s: changed bit-%d: \"%s\" %lx->%lx\n", KP_NAME(kp), cls_id,
map->class_names[cls_id], old_bits, curr_bits);
@@ -742,7 +743,7 @@ static int param_set_dyndbg_module_classes(const char *instr,
inrep &= CLASSMAP_BITMASK(map->length);
}
v2pr_info("bits:0x%lx > %s.%s\n", inrep, modnm ?: "*", KP_NAME(kp));
- totct += ddebug_apply_class_bitmap(dcp, &inrep, dcp->bits, modnm);
+ totct += ddebug_apply_class_bitmap(dcp, &inrep, *dcp->bits, modnm);
*dcp->bits = inrep;
break;
case DD_CLASS_TYPE_LEVEL_NUM:
@@ -755,7 +756,7 @@ static int param_set_dyndbg_module_classes(const char *instr,
old_bits = CLASSMAP_BITMASK(*dcp->lvl);
new_bits = CLASSMAP_BITMASK(inrep);
v2pr_info("lvl:%ld bits:0x%lx > %s\n", inrep, new_bits, KP_NAME(kp));
- totct += ddebug_apply_class_bitmap(dcp, &new_bits, &old_bits, modnm);
+ totct += ddebug_apply_class_bitmap(dcp, &new_bits, old_bits, modnm);
*dcp->lvl = inrep;
break;
default:
--
2.41.0

2023-09-13 01:21:24

by Jim Cromie

[permalink] [raw]
Subject: [PATCH v6 19/22] dyndbg: add _DPRINTK_FLAGS_INCL_LOOKUP

dyndbg's dynamic prefixing (by +tmfsl flags) is needlessly expensive.

When an enabled (with +p) pr_debug is called, _DPRINTK_FLAGS_INCL_ANY
prefix decorations are sprintf'd into stack-mem for every call.

This string (or part of it) could be cached once its 1st generated,
and retreived thereafter, as long as its deleted any time the
callsite's flags are changed afterwards.

So consider the prefix/decoration flags: 'tmfsl', and what should be
in the cache:

-t thread-id. not part of the "callsite" info, derived from current.
doesnt belong in the cache. it would be wrong.
can be done in outer: dynamic_emit_prefix()

-l line number
this could be part of the prefix, but would bloat the cache
can also be done in outer: dynamic_emit_prefix()

-mfs module, function, source-file
we cache these, composed into a sub-string.
they are "lookups", currently to descriptor fields,
could be accessor macros to "compressed" tables.
cache saves more access work.

All enabled together, they compose a prefix string like:

# outer -----inner---------- outer
"[tid] module:function:sourcfile:line: "

So this patch extracts _DPRINTK_FLAGS_INCL_LOOKUP macro out of
_DPRINTK_FLAGS_INCL_ANY macro, then redefs latter.

Next re-refactor dynamic_emit_prefix inner/outer fns accordingly.

Signed-off-by: Jim Cromie <[email protected]>
---
include/linux/dynamic_debug.h | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h
index bdb0d12b13ec..c5609560ca1b 100644
--- a/include/linux/dynamic_debug.h
+++ b/include/linux/dynamic_debug.h
@@ -40,10 +40,12 @@ struct _ddebug {
#define _DPRINTK_FLAGS_INCL_SOURCENAME (1<<5)
#define _DPRINTK_FLAGS_PREFIX_CACHED (1<<7)

-#define _DPRINTK_FLAGS_INCL_ANY \
- (_DPRINTK_FLAGS_INCL_MODNAME | _DPRINTK_FLAGS_INCL_FUNCNAME |\
- _DPRINTK_FLAGS_INCL_LINENO | _DPRINTK_FLAGS_INCL_TID |\
+#define _DPRINTK_FLAGS_INCL_LOOKUP \
+ (_DPRINTK_FLAGS_INCL_MODNAME | _DPRINTK_FLAGS_INCL_FUNCNAME | \
_DPRINTK_FLAGS_INCL_SOURCENAME)
+#define _DPRINTK_FLAGS_INCL_ANY \
+ (_DPRINTK_FLAGS_INCL_LINENO | _DPRINTK_FLAGS_INCL_TID | \
+ _DPRINTK_FLAGS_INCL_LOOKUP)

#if defined DEBUG
#define _DPRINTK_FLAGS_DEFAULT _DPRINTK_FLAGS_PRINT
--
2.41.0

2023-09-13 04:00:44

by Jim Cromie

[permalink] [raw]
Subject: [PATCH v6 06/22] dyndbg: drop NUM_TYPE_ARRAY

ARRAY_SIZE works here, since array decl is complete.

no functional change

Signed-off-by: Jim Cromie <[email protected]>
---
include/linux/dynamic_debug.h | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h
index b53217e4b711..8116d0a0d33a 100644
--- a/include/linux/dynamic_debug.h
+++ b/include/linux/dynamic_debug.h
@@ -106,11 +106,9 @@ struct ddebug_class_map {
.mod_name = KBUILD_MODNAME, \
.base = _base, \
.map_type = _maptype, \
- .length = NUM_TYPE_ARGS(char*, __VA_ARGS__), \
+ .length = ARRAY_SIZE(_var##_classnames), \
.class_names = _var##_classnames, \
}
-#define NUM_TYPE_ARGS(eltype, ...) \
- (sizeof((eltype[]){__VA_ARGS__}) / sizeof(eltype))

/* encapsulate linker provided built-in (or module) dyndbg data */
struct _ddebug_info {
--
2.41.0

2023-09-13 10:58:11

by Jim Cromie

[permalink] [raw]
Subject: [PATCH v6 05/22] dyndbg: split param_set_dyndbg_classes to module/wrapper fns

rename param_set_dyndbg_classes: add _module_ name & arg, old name is
wrapper to new. New arg allows caller to specify that only one module
is affected by a prdbgs update.

Outer fn preserves kernel_param interface, passing NULL to inner fn.
This selectivity will be used later to narrow the scope of changes
made.

no functional change.

Signed-off-by: Jim Cromie <[email protected]>
---
lib/dynamic_debug.c | 37 ++++++++++++++++++++++---------------
1 file changed, 22 insertions(+), 15 deletions(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 592a700adcb8..153e02c3af45 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -708,18 +708,9 @@ static int param_set_dyndbg_classnames(const char *instr, const struct kernel_pa
return 0;
}

-/**
- * param_set_dyndbg_classes - class FOO >control
- * @instr: string echo>d to sysfs, input depends on map_type
- * @kp: kp->arg has state: bits/lvl, map, map_type
- *
- * Enable/disable prdbgs by their class, as given in the arguments to
- * DECLARE_DYNDBG_CLASSMAP. For LEVEL map-types, enforce relative
- * levels by bitpos.
- *
- * Returns: 0 or <0 if error.
- */
-int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp)
+static int param_set_dyndbg_module_classes(const char *instr,
+ const struct kernel_param *kp,
+ const char *modnm)
{
const struct ddebug_class_param *dcp = kp->arg;
const struct ddebug_class_map *map = dcp->map;
@@ -756,8 +747,8 @@ int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp)
KP_NAME(kp), inrep, CLASSMAP_BITMASK(map->length));
inrep &= CLASSMAP_BITMASK(map->length);
}
- v2pr_info("bits:%lx > %s\n", inrep, KP_NAME(kp));
- totct += ddebug_apply_class_bitmap(dcp, &inrep, dcp->bits, NULL);
+ v2pr_info("bits:0x%lx > %s.%s\n", inrep, modnm ?: "*", KP_NAME(kp));
+ totct += ddebug_apply_class_bitmap(dcp, &inrep, dcp->bits, modnm);
*dcp->bits = inrep;
break;
case DD_CLASS_TYPE_LEVEL_NUM:
@@ -770,7 +761,7 @@ int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp)
old_bits = CLASSMAP_BITMASK(*dcp->lvl);
new_bits = CLASSMAP_BITMASK(inrep);
v2pr_info("lvl:%ld bits:0x%lx > %s\n", inrep, new_bits, KP_NAME(kp));
- totct += ddebug_apply_class_bitmap(dcp, &new_bits, &old_bits, NULL);
+ totct += ddebug_apply_class_bitmap(dcp, &new_bits, &old_bits, modnm);
*dcp->lvl = inrep;
break;
default:
@@ -779,6 +770,22 @@ int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp)
vpr_info("%s: total matches: %d\n", KP_NAME(kp), totct);
return 0;
}
+
+/**
+ * param_set_dyndbg_classes - class FOO >control
+ * @instr: string echo>d to sysfs, input depends on map_type
+ * @kp: kp->arg has state: bits/lvl, map, map_type
+ *
+ * Enable/disable prdbgs by their class, as given in the arguments to
+ * DECLARE_DYNDBG_CLASSMAP. For LEVEL map-types, enforce relative
+ * levels by bitpos.
+ *
+ * Returns: 0 or <0 if error.
+ */
+int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp)
+{
+ return param_set_dyndbg_module_classes(instr, kp, NULL);
+}
EXPORT_SYMBOL(param_set_dyndbg_classes);

/**
--
2.41.0

2023-09-13 12:46:06

by Jim Cromie

[permalink] [raw]
Subject: [PATCH v6 12/22] dyndbg-API: fix CONFIG_DRM_USE_DYNAMIC_DEBUG regression

DECLARE_DYNDBG_CLASSMAP() has a design error; it fails a basic K&R
rule: "define once, refer many times".

When DRM_USE_DYNAMIC_DEBUG=y, DECLARE_DYNDBG_CLASSMAP() is used across
DRM core & drivers; they all repeat the same classmap-defn args, which
must match for the modules to respond together when DRM.debug
categories are enabled.

Worse, it causes the CONFIG_DRM_USE_DYNAMIC_DEBUG=Y regression; 1st
drm.ko loads, and dyndbg initializes its DRM.debug callsites, then a
drm-driver loads, but too late - it missed the DRM.debug enablement.

So replace it with 2 macros:
DYNDBG_CLASSMAP_DEFINE - invoked once from core - drm.ko
DYNDBG_CLASSMAP_USE - from all drm drivers and helpers.

DYNDBG_CLASSMAP_DEFINE: based on DECLARE_DYNDBG_CLASSMAP, but now it
drops the static on the constructed classmap variable, and exports it
instead.

DYNDBG_CLASSMAP_USE: then refers to the exported var by name:
* used from drivers, helper-mods
* lets us drop the repetitive "classname" args
* fixes 2nd-defn problem
* creates a ddebug_class_user record in new __dyndbg_class_users section
this allows ddebug_add_module(etal) to handle them per-module.

The distinction, and the usage record, allows dyndbg to initialize the
driver's DRM.debug callsites separately after it is modprobed.

Since DRM now needs updates to use the new macros, it also gets 2
wrappers: DRM_CLASSMAP_DEFINE, DRM_CLASSMAP_USE which declutter the
users by hiding the ifdef CONFIG_DRM_USE_DYNAMIC_DEBUG.

To review, dyndbg's existing __dyndbg_classes[] section does:

. catalogs the classmaps defined by the module (or builtin modules)
. authorizes dyndbg to >control those class'd prdbgs for the module.
. DYNDBG_CLASSMAP_DEFINE(and old one) creates classmaps in this section.

This patch adds __dyndbg_class_users[] section:

. catalogs uses/references to the classmap definitions.
. authorizes dyndbg to >control those class'd prdbgs in ref'g module.
. DYNDBG_CLASSMAP_USE() creates classmap-user records in this section.

Now ddebug_add_module(etal) can handle classmap-uses like (and after)
classmaps; when a dependent module is loaded, its parent's kernel
params are scanned to find the param wired to dyndbg-param-ops, whose
classmap matches the one ref'd by the client.

To support this, a few data/header changes:

. new struct ddebug_class_user
contains: user-module-name, &classmap-defn
it records drm-driver's use of a classmap in the section, allowing lookup

struct ddebug_info gets 2 new fields to encapsulate the new section:
class_users, num_class_users.
set by dynamic_debug_init() for builtins.
or by kernel/module/main:load_info() for loadable modules.

vmlinux.lds.h: new BOUNDED_SECTION for __dyndbg_class_users

dynamic_debug.c has 2 changes in ddebug_add_module(), ddebug_change():

ddebug_add_module() previously called ddebug_attach_module_classes()
to handle classmap DEFINEd by a module, now it also calls
ddebug_attach_user_module_classes() to handle USEd classmaps.

ddebug_attach_user_module_classes() scans the module's class_users
section, follows the refs to the parent's classmap, and calls
ddebug_apply_params() on each.

ddebug_apply_params(new fn):

It scans module's/builtin kernel-params, calls ddebug_match_attach_kparam
for each to find the params/sysfs-nodes which may be wired to a classmap.

ddebug_match_apply_kparam(new fn):

1st, it tests the kernel-param.ops is dyndbg's; this guarantees that
the attached arg is a struct ddebug_class_param, which has a ref to
the param's state, and to the classmap defining the param's handling.

2nd, it requires that the classmap ref'd by the kparam is the one
we're called for; modules can use many separate classmaps (as
test_dynamic_debug does).

Then apply the "parent" kparam's setting to the dependent module,
using ddebug_apply_class_bitmap().

ddebug_change(and callees) also gets adjustments:

ddebug_find_valid_class(): This does a search over the module's
classmaps, looking for the class FOO echo'd to >control. So now it
searches over __dyndbg_class_users[] after __dyndbg_classes[].

ddebug_class_name(): return class-names for defined AND used classes.

test_dynamic_debug.c, test_dynamic_debug_submod.c:

This (already) demonstrates the 2 types of classmaps & sysfs-params,
following the 4-part recipe:

1. define an enum for the classmap: DRM.debug has DRM_UT_{CORE,KMS,...}
multiple classes must share 0-62 classid space.
2. DYNDBG_CLASSMAP_DEFINE(.. DRM_UT_{CORE,KMS,...})
3. DYNDBG_CLASSMAP_PARAM* (classmap)
4. DYNDBG_CLASSMAP_USE()
by _submod only, skipping 2,3

Move all the enum declarations together, to better explain how they
share the 0..62 class-id space available to a module (non-overlapping
subranges).

reorg macros 2,3 by name. This gives a tabular format, making it easy
to see the pattern of repetition, and the points of change.

And extend the test to replicate the 2-module (parent & dependent)
scenario which caused the CONFIG_DRM_USE_DYNAMIC_DEBUG=y regression
seen in drm & drivers.

The _submod.c is a 2-line file: #define _SUBMOD, #include parent.

This gives identical complements of prdbgs in parent & _submod, and
thus identical print behavior when all of: >control, >params, and
parent->_submod propagation are working correctly.

It also puts all the parent/_submod declarations together in the same
source, with the new ifdef _SUBMOD block invoking DYNDBG_CLASSMAP_USE
for the 2 test-interfaces. I think this is clearer.

DEBUG details:

``#define DEBUG`` in src enables all pr_debugs after it, including any
class'd pr_debugs; its not necessarily all-or-nothing, unless its a
one-file-module with DEBUG at the top.

If a CLASSMAP_PARAM is defined on a classmap, its readback value
cannot describe the set of enablements. The param is basically
write-only; it cannot know if `echo $cmd >control` was done since.

To know the exact pr-debug state with certainty, toggle to both:

echo 0x3ff > /sys/module/drm/parameters/debug
echo 0 > /sys/module/drm/parameters/debug

Cc: Daniel Vetter <[email protected]>
Cc: Jani Nikula <[email protected]>
Cc: Tvrtko Ursulin <[email protected]>
Cc: Rob Clark <[email protected]>
Cc: Sean Paul <[email protected]>
Cc: Luis Chamberlain <[email protected]>
Fixes: aad0214f3026 ("dyndbg: add DECLARE_DYNDBG_CLASSMAP macro")
Fixes: f158936b60a7 ("drm: POC drm on dyndbg - use in core, 2 helpers, 3 drivers.")
Ref: commit bb2ff6c27bc9 ("drm: Disable dynamic debug as broken")

Signed-off-by: Jim Cromie <[email protected]>
---
MAINTAINERS | 2 +-
drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 12 +-
drivers/gpu/drm/display/drm_dp_helper.c | 12 +-
drivers/gpu/drm/drm_crtc_helper.c | 12 +-
drivers/gpu/drm/drm_print.c | 25 ++--
drivers/gpu/drm/i915/i915_params.c | 12 +-
drivers/gpu/drm/nouveau/nouveau_drm.c | 12 +-
include/asm-generic/vmlinux.lds.h | 1 +
include/drm/drm_print.h | 10 +-
include/linux/dynamic_debug.h | 54 +++++--
kernel/module/main.c | 3 +
lib/Makefile | 2 +-
lib/dynamic_debug.c | 178 ++++++++++++++++++++----
lib/test_dynamic_debug.c | 127 +++++++++++------
lib/test_dynamic_debug_submod.c | 10 ++
15 files changed, 321 insertions(+), 151 deletions(-)
create mode 100644 lib/test_dynamic_debug_submod.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 4cc6bf79fdd8..774d17b2196a 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7253,7 +7253,7 @@ M: Jim Cromie <[email protected]>
S: Maintained
F: include/linux/dynamic_debug.h
F: lib/dynamic_debug.c
-F: lib/test_dynamic_debug.c
+F: lib/test_dynamic_debug*.c

DYNAMIC INTERRUPT MODERATION
M: Tal Gilboa <[email protected]>
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index 0593ef8fe0a6..e8cb4bab4c39 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -198,17 +198,7 @@ int amdgpu_user_partt_mode = AMDGPU_AUTO_COMPUTE_PARTITION_MODE;

static void amdgpu_drv_delayed_reset_work_handler(struct work_struct *work);

-DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
- "DRM_UT_CORE",
- "DRM_UT_DRIVER",
- "DRM_UT_KMS",
- "DRM_UT_PRIME",
- "DRM_UT_ATOMIC",
- "DRM_UT_VBL",
- "DRM_UT_STATE",
- "DRM_UT_LEASE",
- "DRM_UT_DP",
- "DRM_UT_DRMRES");
+DRM_CLASSMAP_USE(drm_debug_classes);

struct amdgpu_mgpu_info mgpu_info = {
.mutex = __MUTEX_INITIALIZER(mgpu_info.mutex),
diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c
index e6a78fd32380..d97de1a27939 100644
--- a/drivers/gpu/drm/display/drm_dp_helper.c
+++ b/drivers/gpu/drm/display/drm_dp_helper.c
@@ -41,17 +41,7 @@

#include "drm_dp_helper_internal.h"

-DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
- "DRM_UT_CORE",
- "DRM_UT_DRIVER",
- "DRM_UT_KMS",
- "DRM_UT_PRIME",
- "DRM_UT_ATOMIC",
- "DRM_UT_VBL",
- "DRM_UT_STATE",
- "DRM_UT_LEASE",
- "DRM_UT_DP",
- "DRM_UT_DRMRES");
+DRM_CLASSMAP_USE(drm_debug_classes);

struct dp_aux_backlight {
struct backlight_device *base;
diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c
index a209659a996c..fef4662d5f1f 100644
--- a/drivers/gpu/drm/drm_crtc_helper.c
+++ b/drivers/gpu/drm/drm_crtc_helper.c
@@ -50,17 +50,7 @@

#include "drm_crtc_helper_internal.h"

-DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
- "DRM_UT_CORE",
- "DRM_UT_DRIVER",
- "DRM_UT_KMS",
- "DRM_UT_PRIME",
- "DRM_UT_ATOMIC",
- "DRM_UT_VBL",
- "DRM_UT_STATE",
- "DRM_UT_LEASE",
- "DRM_UT_DP",
- "DRM_UT_DRMRES");
+DRM_CLASSMAP_USE(drm_debug_classes);

/**
* DOC: overview
diff --git a/drivers/gpu/drm/drm_print.c b/drivers/gpu/drm/drm_print.c
index 5b93c11895bb..dabcfa0dd279 100644
--- a/drivers/gpu/drm/drm_print.c
+++ b/drivers/gpu/drm/drm_print.c
@@ -55,18 +55,19 @@ MODULE_PARM_DESC(debug, "Enable debug output, where each bit enables a debug cat
#if !defined(CONFIG_DRM_USE_DYNAMIC_DEBUG)
module_param_named(debug, __drm_debug, ulong, 0600);
#else
-/* classnames must match vals of enum drm_debug_category */
-DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
- "DRM_UT_CORE",
- "DRM_UT_DRIVER",
- "DRM_UT_KMS",
- "DRM_UT_PRIME",
- "DRM_UT_ATOMIC",
- "DRM_UT_VBL",
- "DRM_UT_STATE",
- "DRM_UT_LEASE",
- "DRM_UT_DP",
- "DRM_UT_DRMRES");
+/* classnames must match value-symbols of enum drm_debug_category */
+DRM_CLASSMAP_DEFINE(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS,
+ DRM_UT_CORE,
+ "DRM_UT_CORE",
+ "DRM_UT_DRIVER",
+ "DRM_UT_KMS",
+ "DRM_UT_PRIME",
+ "DRM_UT_ATOMIC",
+ "DRM_UT_VBL",
+ "DRM_UT_STATE",
+ "DRM_UT_LEASE",
+ "DRM_UT_DP",
+ "DRM_UT_DRMRES");

static struct ddebug_class_param drm_debug_bitmap = {
.bits = &__drm_debug,
diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c
index 0a171b57fd8f..d870e15da21c 100644
--- a/drivers/gpu/drm/i915/i915_params.c
+++ b/drivers/gpu/drm/i915/i915_params.c
@@ -29,17 +29,7 @@
#include "i915_params.h"
#include "i915_drv.h"

-DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
- "DRM_UT_CORE",
- "DRM_UT_DRIVER",
- "DRM_UT_KMS",
- "DRM_UT_PRIME",
- "DRM_UT_ATOMIC",
- "DRM_UT_VBL",
- "DRM_UT_STATE",
- "DRM_UT_LEASE",
- "DRM_UT_DP",
- "DRM_UT_DRMRES");
+DRM_CLASSMAP_USE(drm_debug_classes);

#define i915_param_named(name, T, perm, desc) \
module_param_named(name, i915_modparams.name, T, perm); \
diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c
index 40fb9a834918..5e8179db86f5 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_drm.c
@@ -69,17 +69,7 @@
#include "nouveau_svm.h"
#include "nouveau_dmem.h"

-DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
- "DRM_UT_CORE",
- "DRM_UT_DRIVER",
- "DRM_UT_KMS",
- "DRM_UT_PRIME",
- "DRM_UT_ATOMIC",
- "DRM_UT_VBL",
- "DRM_UT_STATE",
- "DRM_UT_LEASE",
- "DRM_UT_DP",
- "DRM_UT_DRMRES");
+DRM_CLASSMAP_USE(drm_debug_classes);

MODULE_PARM_DESC(config, "option string to pass to driver core");
static char *nouveau_config;
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index 9c59409104f6..e00b6380089c 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -373,6 +373,7 @@
/* implement dynamic printk debug */ \
. = ALIGN(8); \
BOUNDED_SECTION_BY(__dyndbg_classes, ___dyndbg_classes) \
+ BOUNDED_SECTION_BY(__dyndbg_class_users, ___dyndbg_class_users) \
BOUNDED_SECTION_BY(__dyndbg, ___dyndbg) \
LIKELY_PROFILE() \
BRANCH_PROFILE() \
diff --git a/include/drm/drm_print.h b/include/drm/drm_print.h
index a93a387f8a1a..706afc97c79c 100644
--- a/include/drm/drm_print.h
+++ b/include/drm/drm_print.h
@@ -276,7 +276,7 @@ static inline struct drm_printer drm_err_printer(const char *prefix)
*
*/
enum drm_debug_category {
- /* These names must match those in DYNAMIC_DEBUG_CLASSBITS */
+ /* Keep DRM_CLASSMAP_DEFINE args in sync with any changes here */
/**
* @DRM_UT_CORE: Used in the generic drm code: drm_ioctl.c, drm_mm.c,
* drm_memory.c, ...
@@ -321,6 +321,14 @@ enum drm_debug_category {
DRM_UT_DRMRES
};

+#ifdef CONFIG_DRM_USE_DYNAMIC_DEBUG
+#define DRM_CLASSMAP_DEFINE(...) DYNDBG_CLASSMAP_DEFINE(__VA_ARGS__)
+#define DRM_CLASSMAP_USE(name) DYNDBG_CLASSMAP_USE(name)
+#else
+#define DRM_CLASSMAP_DEFINE(...)
+#define DRM_CLASSMAP_USE(name)
+#endif
+
static inline bool drm_debug_enabled_raw(enum drm_debug_category category)
{
return unlikely(__drm_debug & BIT(category));
diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h
index 8eaf8eabdc8d..dfd5e39ee4d0 100644
--- a/include/linux/dynamic_debug.h
+++ b/include/linux/dynamic_debug.h
@@ -58,7 +58,7 @@ struct _ddebug {
#endif
} __attribute__((aligned(8)));

-enum class_map_type {
+enum ddebug_class_map_type {
DD_CLASS_TYPE_DISJOINT_BITS,
/**
* DD_CLASS_TYPE_DISJOINT_BITS: classes are independent, mapped to bits[0..N].
@@ -72,24 +72,28 @@ enum class_map_type {
};

struct ddebug_class_map {
- struct module *mod;
- const char *mod_name; /* needed for builtins */
+ const struct module *mod; /* NULL for builtins */
+ const char *mod_name;
const char **class_names;
const int length;
const int base; /* index of 1st .class_id, allows split/shared space */
- enum class_map_type map_type;
+ enum ddebug_class_map_type map_type;
};

/**
- * DECLARE_DYNDBG_CLASSMAP - declare classnames known by a module
- * @_var: a struct ddebug_class_map, passed to module_param_cb
- * @_type: enum class_map_type, chooses bits/verbose, numeric/symbolic
- * @_base: offset of 1st class-name. splits .class_id space
- * @classes: class-names used to control class'd prdbgs
+ * DYNDBG_CLASSMAP_DEFINE - define a set of debug-classes used by a module.
+ * @_var: name of the classmap, exported for other modules coordinated use.
+ * @_type: enum ddebug_class_map_type, chooses bits/verbose, numeric/names.
+ * @_base: offset of 1st class-name, used to share 0..62 classid space
+ * @classes: vals are stringified enum-vals, like DRM_UT_*
+ *
+ * Defines and exports a struct ddebug_class_map whose @classes are
+ * used to validate a "class FOO .." >control command against each
+ * module, and to validate inputs to DD_CLASS_TYPE_*_NAMES typed params.
*/
-#define DECLARE_DYNDBG_CLASSMAP(_var, _maptype, _base, ...) \
- static const char *_var##_classnames[] = { __VA_ARGS__ }; \
- static struct ddebug_class_map __aligned(8) __used \
+#define DYNDBG_CLASSMAP_DEFINE(_var, _maptype, _base, ...) \
+ const char *_var##_classnames[] = { __VA_ARGS__ }; \
+ struct ddebug_class_map __aligned(8) __used \
__section("__dyndbg_classes") _var = { \
.mod = THIS_MODULE, \
.mod_name = KBUILD_MODNAME, \
@@ -97,14 +101,40 @@ struct ddebug_class_map {
.map_type = _maptype, \
.length = ARRAY_SIZE(_var##_classnames), \
.class_names = _var##_classnames, \
+ }; \
+ EXPORT_SYMBOL(_var)
+
+struct ddebug_class_user {
+ char *user_mod_name;
+ struct ddebug_class_map *map;
+};
+
+/**
+ * DYNDBG_CLASSMAP_USE - refer to a classmap, DEFINEd elsewhere.
+ * @_var: name of the exported classmap var
+ *
+ * This registers a module's use of another module's classmap defn, so
+ * dyndbg can authorize "class DRM_CORE ..." >control commands upon
+ * this module.
+ */
+#define DYNDBG_CLASSMAP_USE(_var) \
+ DYNDBG_CLASSMAP_USE_(_var, __UNIQUE_ID(ddebug_class_user))
+#define DYNDBG_CLASSMAP_USE_(_var, _uname) \
+ extern struct ddebug_class_map _var; \
+ struct ddebug_class_user __used \
+ __section("__dyndbg_class_users") _uname = { \
+ .user_mod_name = KBUILD_MODNAME, \
+ .map = &_var, \
}

/* encapsulate linker provided built-in (or module) dyndbg data */
struct _ddebug_info {
struct _ddebug *descs;
struct ddebug_class_map *classes;
+ struct ddebug_class_user *class_users;
unsigned int num_descs;
unsigned int num_classes;
+ unsigned int num_class_users;
};

struct ddebug_class_param {
diff --git a/kernel/module/main.c b/kernel/module/main.c
index 59b1d067e528..ffcbb07e3782 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -2206,6 +2206,9 @@ static int find_module_sections(struct module *mod, struct load_info *info)
mod->dyndbg_info.classes = section_objs(info, "__dyndbg_classes",
sizeof(*mod->dyndbg_info.classes),
&mod->dyndbg_info.num_classes);
+ mod->dyndbg_info.class_users = section_objs(info, "__dyndbg_class_users",
+ sizeof(*mod->dyndbg_info.class_users),
+ &mod->dyndbg_info.num_class_users);
#endif

return 0;
diff --git a/lib/Makefile b/lib/Makefile
index 1ffae65bb7ee..31195c75f5a0 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -79,7 +79,7 @@ obj-$(CONFIG_TEST_SORT) += test_sort.o
obj-$(CONFIG_TEST_USER_COPY) += test_user_copy.o
obj-$(CONFIG_TEST_STATIC_KEYS) += test_static_keys.o
obj-$(CONFIG_TEST_STATIC_KEYS) += test_static_key_base.o
-obj-$(CONFIG_TEST_DYNAMIC_DEBUG) += test_dynamic_debug.o
+obj-$(CONFIG_TEST_DYNAMIC_DEBUG) += test_dynamic_debug.o test_dynamic_debug_submod.o
obj-$(CONFIG_TEST_PRINTF) += test_printf.o
obj-$(CONFIG_TEST_SCANF) += test_scanf.o

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 6fd945e6719e..018578923897 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -43,13 +43,16 @@ extern struct _ddebug __start___dyndbg[];
extern struct _ddebug __stop___dyndbg[];
extern struct ddebug_class_map __start___dyndbg_classes[];
extern struct ddebug_class_map __stop___dyndbg_classes[];
+extern struct ddebug_class_user __start___dyndbg_class_users[];
+extern struct ddebug_class_user __stop___dyndbg_class_users[];

struct ddebug_table {
struct list_head link;
const char *mod_name;
struct _ddebug *ddebugs;
struct ddebug_class_map *classes;
- unsigned int num_ddebugs, num_classes;
+ struct ddebug_class_user *class_users;
+ unsigned int num_ddebugs, num_classes, num_class_users;
};

struct ddebug_query {
@@ -148,21 +151,39 @@ static void vpr_info_dq(const struct ddebug_query *query, const char *msg)
query->first_lineno, query->last_lineno, query->class_string);
}

+#define vpr_dt_info(dt_p, msg_p, ...) ({ \
+ struct ddebug_table const *_dt = dt_p; \
+ v2pr_info(msg_p " module:%s nd:%d nc:%d nu:%d\n", ##__VA_ARGS__, \
+ _dt->mod_name, _dt->num_ddebugs, _dt->num_classes, \
+ _dt->num_class_users); \
+ })
+
#define __outvar /* filled by callee */
static struct ddebug_class_map *ddebug_find_valid_class(struct ddebug_table const *dt,
const char *class_string,
__outvar int *class_id)
{
struct ddebug_class_map *map;
+ struct ddebug_class_user *cli;
int i, idx;

- for (map = dt->classes, i = 0; i < dt->num_classes; i++, map++) {
+ for (i = 0, map = dt->classes; i < dt->num_classes; i++, map++) {
idx = match_string(map->class_names, map->length, class_string);
if (idx >= 0) {
*class_id = idx + map->base;
+ vpr_dt_info(dt, "good-class: %s.%s ", map->mod_name, class_string);
return map;
}
}
+ for (i = 0, cli = dt->class_users; i < dt->num_class_users; i++, cli++) {
+ idx = match_string(cli->map->class_names, cli->map->length, class_string);
+ if (idx >= 0) {
+ *class_id = idx + cli->map->base;
+ vpr_dt_info(dt, "class-ref: %s.%s ",
+ cli->user_mod_name, class_string);
+ return cli->map;
+ }
+ }
*class_id = -ENOENT;
return NULL;
}
@@ -555,7 +576,7 @@ static int ddebug_exec_query(char *query_string, const char *modname)

/* handle multiple queries in query string, continue on error, return
last error or number of matching callsites. Module name is either
- in param (for boot arg) or perhaps in query string.
+ in the modname arg (for boot args) or perhaps in query string.
*/
static int ddebug_exec_queries(char *query, const char *modname)
{
@@ -684,12 +705,12 @@ static int param_set_dyndbg_module_classes(const char *instr,
}

/**
- * param_set_dyndbg_classes - class FOO >control
+ * param_set_dyndbg_classes - set all classes in a classmap
* @instr: string echo>d to sysfs, input depends on map_type
- * @kp: kp->arg has state: bits/lvl, map, map_type
+ * @kp: kp->arg has state: bits/lvl, classmap, map_type
*
- * Enable/disable prdbgs by their class, as given in the arguments to
- * DECLARE_DYNDBG_CLASSMAP. For LEVEL map-types, enforce relative
+ * For all classes in the classmap, enable/disable them per the input
+ * (depending on map_type). For LEVEL map-types, enforce relative
* levels by bitpos.
*
* Returns: 0 or <0 if error.
@@ -1034,12 +1055,17 @@ static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos)
static const char *ddebug_class_name(struct ddebug_table *dt, struct _ddebug *dp)
{
struct ddebug_class_map *map = dt->classes;
+ struct ddebug_class_user *cli = dt->class_users;
int i;

for (i = 0; i < dt->num_classes; i++, map++)
if (class_in_range(dp->class_id, map))
return map->class_names[dp->class_id - map->base];

+ for (i = 0; i < dt->num_class_users; i++, cli++)
+ if (class_in_range(dp->class_id, cli->map))
+ return cli->map->class_names[dp->class_id - cli->map->base];
+
return NULL;
}

@@ -1120,31 +1146,129 @@ static const struct proc_ops proc_fops = {
.proc_write = ddebug_proc_write
};

+static const char * const ddebug_classmap_typenames[] = {
+ "DISJOINT_BITS", "LEVEL_NUM", "DISJOINT_NAMES", "LEVEL_NAMES"
+};
+
+#define vpr_cm_info(cm_p, msg_p, ...) ({ \
+ struct ddebug_class_map const *_cm = cm_p; \
+ v2pr_info(msg_p " module:%s base:%d len:%d type:%s\n", ##__VA_ARGS__, \
+ _cm->mod_name, _cm->base, _cm->length, \
+ ddebug_classmap_typenames[_cm->map_type]); \
+ })
+
+static void ddebug_sync_classbits(const struct ddebug_class_param *dcp, const char *modname)
+{
+ /* clamp initial bitvec, mask off hi-bits */
+ if (*dcp->bits & ~CLASSMAP_BITMASK(dcp->map->length)) {
+ *dcp->bits &= CLASSMAP_BITMASK(dcp->map->length);
+ v2pr_info("preset classbits: %lx\n", *dcp->bits);
+ }
+ /* force class'd prdbgs (in USEr module) to match (DEFINEr module) class-param */
+ ddebug_apply_class_bitmap(dcp, dcp->bits, ~0, modname);
+ ddebug_apply_class_bitmap(dcp, dcp->bits, 0, modname);
+}
+
+static void ddebug_match_apply_kparam(const struct kernel_param *kp,
+ const struct ddebug_class_map *map,
+ const char *modnm)
+{
+ struct ddebug_class_param *dcp;
+
+ if (kp->ops != &param_ops_dyndbg_classes)
+ return;
+
+ dcp = (struct ddebug_class_param *)kp->arg;
+
+ if (map == dcp->map) {
+ v2pr_info("found kp:%s =0x%lx", kp->name, *dcp->bits);
+ vpr_cm_info(map, "mapped to:");
+ ddebug_sync_classbits(dcp, modnm);
+ }
+}
+
+static void ddebug_apply_params(const struct ddebug_class_map *cm, const char *modnm)
+{
+ const struct kernel_param *kp;
+#if IS_ENABLED(CONFIG_MODULES)
+ int i;
+
+ if (cm->mod) {
+ vpr_cm_info(cm, "loaded class:");
+ for (i = 0, kp = cm->mod->kp; i < cm->mod->num_kp; i++, kp++)
+ ddebug_match_apply_kparam(kp, cm, modnm);
+ }
+#endif
+ if (!cm->mod) {
+ vpr_cm_info(cm, "builtin class:");
+ for (kp = __start___param; kp < __stop___param; kp++)
+ ddebug_match_apply_kparam(kp, cm, modnm);
+ }
+}
+
+/*
+ * Find this module's classmaps in a sub/whole-range of the builtin/
+ * modular classmap vector/section. Save the start and length of the
+ * subrange at its edges.
+ */
static void ddebug_attach_module_classes(struct ddebug_table *dt, struct _ddebug_info *di)
{
struct ddebug_class_map *cm;
int i, nc = 0;

- /*
- * Find this module's classmaps in a subrange/wholerange of
- * the builtin/modular classmap vector/section. Save the start
- * and length of the subrange at its edges.
- */
- for (cm = di->classes, i = 0; i < di->num_classes; i++, cm++) {
+ for (i = 0, cm = di->classes; i < di->num_classes; i++, cm++) {

if (!strcmp(cm->mod_name, dt->mod_name)) {
- if (!nc) {
- v2pr_info("start subrange, class[%d]: module:%s base:%d len:%d ty:%d\n",
- i, cm->mod_name, cm->base, cm->length, cm->map_type);
+ vpr_cm_info(cm, "classes[%d]:", i);
+ if (!nc++)
dt->classes = cm;
- }
- nc++;
}
}
- if (nc) {
- dt->num_classes = nc;
+ dt->num_classes = nc;
+ if (nc)
vpr_info("module:%s attached %d classes\n", dt->mod_name, nc);
+
+ /* now iterate dt */
+ for (i = 0, cm = dt->classes; i < dt->num_classes; i++, cm++)
+ ddebug_apply_params(cm, cm->mod_name);
+}
+
+/*
+ * propagates class-params thru their classmaps to class-users. this
+ * means a query against the dt/module, which means it must be on the
+ * list to be seen by ddebug_change.
+ */
+static void ddebug_attach_user_module_classes(struct ddebug_table *dt,
+ const struct _ddebug_info *di)
+{
+ struct ddebug_class_user *cli;
+ int i, nc = 0;
+
+ /*
+ * For builtins: scan the array, find start/length of this
+ * module's refs, save to dt. For loadables, this is the
+ * whole array.
+ */
+ for (i = 0, cli = di->class_users; i < di->num_class_users; i++, cli++) {
+
+ if (WARN_ON(!cli || !cli->map || !cli->user_mod_name))
+ continue;
+
+ if (!strcmp(cli->user_mod_name, dt->mod_name)) {
+
+ vpr_cm_info(cli->map, "class_ref[%d] %s -> %s", i,
+ cli->user_mod_name, cli->map->mod_name);
+ if (!nc++)
+ dt->class_users = cli;
+ }
}
+ dt->num_class_users = nc;
+
+ /* now iterate dt */
+ for (i = 0, cli = dt->class_users; i < dt->num_class_users; i++, cli++)
+ ddebug_apply_params(cli->map, cli->user_mod_name);
+
+ vpr_dt_info(dt, "attach-client-module: ");
}

/*
@@ -1155,7 +1279,8 @@ static int ddebug_add_module(struct _ddebug_info *di, const char *modname)
{
struct ddebug_table *dt;

- v3pr_info("add-module: %s.%d sites\n", modname, di->num_descs);
+ v3pr_info("add-module: %s %d sites %d.%d\n", modname, di->num_descs,
+ di->num_classes, di->num_class_users);
if (!di->num_descs) {
v3pr_info(" skip %s\n", modname);
return 0;
@@ -1178,13 +1303,16 @@ static int ddebug_add_module(struct _ddebug_info *di, const char *modname)

INIT_LIST_HEAD(&dt->link);

- if (di->classes && di->num_classes)
- ddebug_attach_module_classes(dt, di);
-
mutex_lock(&ddebug_lock);
list_add_tail(&dt->link, &ddebug_tables);
mutex_unlock(&ddebug_lock);

+ if (di->num_classes)
+ ddebug_attach_module_classes(dt, di);
+
+ if (di->num_class_users)
+ ddebug_attach_user_module_classes(dt, di);
+
vpr_info("%3u debug prints in module %s\n", di->num_descs, modname);
return 0;
}
@@ -1334,8 +1462,10 @@ static int __init dynamic_debug_init(void)
struct _ddebug_info di = {
.descs = __start___dyndbg,
.classes = __start___dyndbg_classes,
+ .class_users = __start___dyndbg_class_users,
.num_descs = __stop___dyndbg - __start___dyndbg,
.num_classes = __stop___dyndbg_classes - __start___dyndbg_classes,
+ .num_class_users = __stop___dyndbg_class_users - __start___dyndbg_class_users,
};

#ifdef CONFIG_MODULES
diff --git a/lib/test_dynamic_debug.c b/lib/test_dynamic_debug.c
index 229eaadee838..23967071b60f 100644
--- a/lib/test_dynamic_debug.c
+++ b/lib/test_dynamic_debug.c
@@ -6,11 +6,15 @@
* Jim Cromie <[email protected]>
*/

-#define pr_fmt(fmt) "test_dd: " fmt
+#if defined(TEST_DYNAMIC_DEBUG_SUBMOD)
+ #define pr_fmt(fmt) "test_dd_submod: " fmt
+#else
+ #define pr_fmt(fmt) "test_dd: " fmt
+#endif

#include <linux/module.h>

-/* run tests by reading or writing sysfs node: do_prints */
+/* re-gen output 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)
@@ -29,24 +33,39 @@ static const struct kernel_param_ops param_ops_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 = { \
+#define CLASSMAP_BITMASK(width, base) (((1UL << (width)) - 1) << base)
+
+/* sysfs param wrapper, proto-API */
+#define DYNDBG_CLASSMAP_PARAM_(_model, _flags, _init) \
+ static unsigned long bits_##_model = _init; \
+ 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)
+ module_param_cb(_flags##_##_model, &param_ops_dyndbg_classes, \
+ &_flags##_##_model, 0600)
+#ifdef DEBUG
+#define DYNDBG_CLASSMAP_PARAM(_model, _flags) DYNDBG_CLASSMAP_PARAM_(_model, _flags, ~0)
+#else
+#define DYNDBG_CLASSMAP_PARAM(_model, _flags) DYNDBG_CLASSMAP_PARAM_(_model, _flags, 0)
+#endif
+
+/*
+ * Demonstrate/test all 4 class-typed classmaps with a sys-param.
+ *
+ * Each is 3 part: client-enum decl, _DEFINE, _PARAM.
+ * Declare them in blocks to show patterns of use (repetitions and
+ * changes) within each.
+ *
+ * 1st, dyndbg expects a client-provided enum-type as source of
+ * category/classid truth. DRM has DRM_UT_<CORE,DRIVER,KMS,etc>.
+ *
+ * Modules with multiple CLASSMAPS must have enums with distinct
+ * value-ranges, arranged below with explicit enum_sym = X inits.
+ *
+ * Declare all 4 enums now, for different types
+ */

/* numeric input, independent bits */
enum cat_disjoint_bits {
@@ -60,40 +79,57 @@ enum cat_disjoint_bits {
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 = 10, 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 */
+/* named-symbolic input, independent bits */
+enum cat_disjoint_names { LOW = 10, MID, HI };
+
+/* named-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);
+
+/* recapitulate DRM's parent(drm.ko) <-- _submod(drivers,helpers) */
+#if !defined(TEST_DYNAMIC_DEBUG_SUBMOD)
+/*
+ * In single user, or parent / coordinator (drm.ko) modules, define
+ * classmaps on the client enums above, and then declares the PARAMS
+ * ref'g the classmaps. Each is exported.
+ */
+DYNDBG_CLASSMAP_DEFINE(map_disjoint_bits, DD_CLASS_TYPE_DISJOINT_BITS,
+ D2_CORE,
+ "D2_CORE",
+ "D2_DRIVER",
+ "D2_KMS",
+ "D2_PRIME",
+ "D2_ATOMIC",
+ "D2_VBL",
+ "D2_STATE",
+ "D2_LEASE",
+ "D2_DP",
+ "D2_DRMRES");
+
+DYNDBG_CLASSMAP_DEFINE(map_level_num, DD_CLASS_TYPE_LEVEL_NUM,
+ V0, "V0", "V1", "V2", "V3", "V4", "V5", "V6", "V7");
+
+/*
+ * now add the sysfs-params
+ */
+
+DYNDBG_CLASSMAP_PARAM(disjoint_bits, p);
+DYNDBG_CLASSMAP_PARAM(level_num, p);
+
+#else /* TEST_DYNAMIC_DEBUG_SUBMOD */
+
+/*
+ * in submod/drm-drivers, use the classmaps defined in top/parent
+ * module above.
+ */
+
+DYNDBG_CLASSMAP_USE(map_disjoint_bits);
+DYNDBG_CLASSMAP_USE(map_level_num);
+
+#endif

/* stand-in for all pr_debug etc */
#define prdbg(SYM) __pr_debug_cls(SYM, #SYM " msg\n")
@@ -129,6 +165,7 @@ static void do_levels(void)

static void do_prints(void)
{
+ pr_debug("do_prints:\n");
do_cats();
do_levels();
}
diff --git a/lib/test_dynamic_debug_submod.c b/lib/test_dynamic_debug_submod.c
new file mode 100644
index 000000000000..9a893402ce1a
--- /dev/null
+++ b/lib/test_dynamic_debug_submod.c
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Kernel module for testing dynamic_debug
+ *
+ * Authors:
+ * Jim Cromie <[email protected]>
+ */
+
+#define TEST_DYNAMIC_DEBUG_SUBMOD
+#include "test_dynamic_debug.c"
--
2.41.0

2023-09-14 01:52:11

by Jim Cromie

[permalink] [raw]
Subject: [PATCH v6 04/22] dyndbg: ddebug_apply_class_bitmap - add module arg, select on it

Add query_module param to ddebug_apply_class_bitmap(). This allows
its caller to update just one module, or all (as currently). We'll
use this later to propagate drm.debug to each USEr as they're
modprobed.

No functional change.

Signed-off-by: Jim Cromie <[email protected]>
---

after `modprobe i915`, heres the module dependencies,
though not all on drm.debug.

bash-5.2# lsmod
Module Size Used by
i915 3133440 0
drm_buddy 20480 1 i915
ttm 90112 1 i915
i2c_algo_bit 16384 1 i915
video 61440 1 i915
wmi 32768 1 video
drm_display_helper 200704 1 i915
drm_kms_helper 208896 2 drm_display_helper,i915
drm 606208 5 drm_kms_helper,drm_display_helper,drm_buddy,i915,ttm
cec 57344 2 drm_display_helper,i915
---
lib/dynamic_debug.c | 19 ++++++++++++-------
1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 8b46d56f73a5..592a700adcb8 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -601,7 +601,8 @@ static int ddebug_exec_queries(char *query, const char *modname)

/* apply a new bitmap to the sys-knob's current bit-state */
static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp,
- unsigned long *new_bits, unsigned long *old_bits)
+ unsigned long *new_bits, unsigned long *old_bits,
+ const char *query_modname)
{
#define QUERY_SIZE 128
char query[QUERY_SIZE];
@@ -609,7 +610,8 @@ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp,
int matches = 0;
int bi, ct;

- v2pr_info("apply: 0x%lx to: 0x%lx\n", *new_bits, *old_bits);
+ v2pr_info("apply bitmap: 0x%lx to: 0x%lx for %s\n", *new_bits, *old_bits,
+ query_modname ?: "");

for (bi = 0; bi < map->length; bi++) {
if (test_bit(bi, new_bits) == test_bit(bi, old_bits))
@@ -618,12 +620,15 @@ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp,
snprintf(query, QUERY_SIZE, "class %s %c%s", map->class_names[bi],
test_bit(bi, new_bits) ? '+' : '-', dcp->flags);

- ct = ddebug_exec_queries(query, NULL);
+ ct = ddebug_exec_queries(query, query_modname);
matches += ct;

v2pr_info("bit_%d: %d matches on class: %s -> 0x%lx\n", bi,
ct, map->class_names[bi], *new_bits);
}
+ v2pr_info("applied bitmap: 0x%lx to: 0x%lx for %s\n", *new_bits, *old_bits,
+ query_modname ?: "");
+
return matches;
}

@@ -679,7 +684,7 @@ static int param_set_dyndbg_classnames(const char *instr, const struct kernel_pa
continue;
}
curr_bits ^= BIT(cls_id);
- totct += ddebug_apply_class_bitmap(dcp, &curr_bits, dcp->bits);
+ totct += ddebug_apply_class_bitmap(dcp, &curr_bits, dcp->bits, NULL);
*dcp->bits = curr_bits;
v2pr_info("%s: changed bit %d:%s\n", KP_NAME(kp), cls_id,
map->class_names[cls_id]);
@@ -689,7 +694,7 @@ static int param_set_dyndbg_classnames(const char *instr, const struct kernel_pa
old_bits = CLASSMAP_BITMASK(*dcp->lvl);
curr_bits = CLASSMAP_BITMASK(cls_id + (wanted ? 1 : 0 ));

- totct += ddebug_apply_class_bitmap(dcp, &curr_bits, &old_bits);
+ totct += ddebug_apply_class_bitmap(dcp, &curr_bits, &old_bits, NULL);
*dcp->lvl = (cls_id + (wanted ? 1 : 0));
v2pr_info("%s: changed bit-%d: \"%s\" %lx->%lx\n", KP_NAME(kp), cls_id,
map->class_names[cls_id], old_bits, curr_bits);
@@ -752,7 +757,7 @@ int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp)
inrep &= CLASSMAP_BITMASK(map->length);
}
v2pr_info("bits:%lx > %s\n", inrep, KP_NAME(kp));
- totct += ddebug_apply_class_bitmap(dcp, &inrep, dcp->bits);
+ totct += ddebug_apply_class_bitmap(dcp, &inrep, dcp->bits, NULL);
*dcp->bits = inrep;
break;
case DD_CLASS_TYPE_LEVEL_NUM:
@@ -765,7 +770,7 @@ int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp)
old_bits = CLASSMAP_BITMASK(*dcp->lvl);
new_bits = CLASSMAP_BITMASK(inrep);
v2pr_info("lvl:%ld bits:0x%lx > %s\n", inrep, new_bits, KP_NAME(kp));
- totct += ddebug_apply_class_bitmap(dcp, &new_bits, &old_bits);
+ totct += ddebug_apply_class_bitmap(dcp, &new_bits, &old_bits, NULL);
*dcp->lvl = inrep;
break;
default:
--
2.41.0

2023-09-14 16:24:30

by Jim Cromie

[permalink] [raw]
Subject: [PATCH v6 21/22] drm: use correct ccflags-y spelling

Incorrectly spelled CFLAGS- failed to add -DDYNAMIC_DEBUG_MODULE,
which broke builds with:

CONFIG_DRM_USE_DYNAMIC_DEBUG=y
CONFIG_DYNAMIC_DEBUG_CORE=y
CONFIG_DYNAMIC_DEBUG=n

Also add subdir-ccflags so that all drivers pick up the addition.

Fixes: 84ec67288c10 ("drm_print: wrap drm_*_dbg in dyndbg descriptor factory macro")
Signed-off-by: Jim Cromie <[email protected]>
---
drivers/gpu/drm/Makefile | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index 7a09a89b493b..013cde886326 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -3,7 +3,8 @@
# Makefile for the drm device driver. This driver provides support for the
# Direct Rendering Infrastructure (DRI) in XFree86 4.1.0 and higher.

-CFLAGS-$(CONFIG_DRM_USE_DYNAMIC_DEBUG) += -DDYNAMIC_DEBUG_MODULE
+ccflags-$(CONFIG_DRM_USE_DYNAMIC_DEBUG) += -DDYNAMIC_DEBUG_MODULE
+subdir-ccflags-$(CONFIG_DRM_USE_DYNAMIC_DEBUG) += -DDYNAMIC_DEBUG_MODULE

drm-y := \
drm_aperture.o \
--
2.41.0