[PATCH 2/2] cgroup/misc: Change counters to be explicit 64bit types

From: Haitao Huang
Date: Mon Jul 17 2023 - 21:09:11 EST


So the variables can account for resources of huge quantities even on
32-bit machines.

Signed-off-by: Haitao Huang <haitao.huang@xxxxxxxxxxxxxxx>
---
include/linux/misc_cgroup.h | 22 +++++++--------
kernel/cgroup/misc.c | 53 +++++++++++++++++++------------------
2 files changed, 38 insertions(+), 37 deletions(-)

diff --git a/include/linux/misc_cgroup.h b/include/linux/misc_cgroup.h
index c238207d1615..2751cf12796d 100644
--- a/include/linux/misc_cgroup.h
+++ b/include/linux/misc_cgroup.h
@@ -34,9 +34,9 @@ struct misc_cg;
* @failed: True if charged failed for the resource in a cgroup.
*/
struct misc_res {
- unsigned long max;
- atomic_long_t usage;
- atomic_long_t events;
+ u64 max;
+ atomic64_t usage;
+ atomic64_t events;
};

/**
@@ -53,12 +53,12 @@ struct misc_cg {
struct misc_res res[MISC_CG_RES_TYPES];
};

-unsigned long misc_cg_res_total_usage(enum misc_res_type type);
-int misc_cg_set_capacity(enum misc_res_type type, unsigned long capacity);
+u64 misc_cg_res_total_usage(enum misc_res_type type);
+int misc_cg_set_capacity(enum misc_res_type type, u64 capacity);
int misc_cg_try_charge(enum misc_res_type type, struct misc_cg *cg,
- unsigned long amount);
+ u64 amount);
void misc_cg_uncharge(enum misc_res_type type, struct misc_cg *cg,
- unsigned long amount);
+ u64 amount);

/**
* css_misc() - Get misc cgroup from the css.
@@ -99,27 +99,27 @@ static inline void put_misc_cg(struct misc_cg *cg)

#else /* !CONFIG_CGROUP_MISC */

-static inline unsigned long misc_cg_res_total_usage(enum misc_res_type type)
+static inline u64 misc_cg_res_total_usage(enum misc_res_type type)
{
return 0;
}

static inline int misc_cg_set_capacity(enum misc_res_type type,
- unsigned long capacity)
+ u64 capacity)
{
return 0;
}

static inline int misc_cg_try_charge(enum misc_res_type type,
struct misc_cg *cg,
- unsigned long amount)
+ u64 amount)
{
return 0;
}

static inline void misc_cg_uncharge(enum misc_res_type type,
struct misc_cg *cg,
- unsigned long amount)
+ u64 amount)
{
}

diff --git a/kernel/cgroup/misc.c b/kernel/cgroup/misc.c
index b127607837c6..c4546e99cde4 100644
--- a/kernel/cgroup/misc.c
+++ b/kernel/cgroup/misc.c
@@ -14,7 +14,7 @@
#include <linux/misc_cgroup.h>

#define MAX_STR "max"
-#define MAX_NUM ULONG_MAX
+#define MAX_NUM U64_MAX

/* Miscellaneous res name, keep it in sync with enum misc_res_type */
static const char *const misc_res_name[] = {
@@ -37,7 +37,7 @@ static struct misc_cg root_cg;
* more than the actual capacity. We are using Limits resource distribution
* model of cgroup for miscellaneous controller.
*/
-static unsigned long misc_res_capacity[MISC_CG_RES_TYPES];
+static u64 misc_res_capacity[MISC_CG_RES_TYPES];

/**
* parent_misc() - Get the parent of the passed misc cgroup.
@@ -74,10 +74,10 @@ static inline bool valid_type(enum misc_res_type type)
* Context: Any context.
* Return: Current total usage of the resource.
*/
-unsigned long misc_cg_res_total_usage(enum misc_res_type type)
+u64 misc_cg_res_total_usage(enum misc_res_type type)
{
if (valid_type(type))
- return atomic_long_read(&root_cg.res[type].usage);
+ return atomic64_read(&root_cg.res[type].usage);

return 0;
}
@@ -95,7 +95,7 @@ EXPORT_SYMBOL_GPL(misc_cg_res_total_usage);
* * %0 - Successfully registered the capacity.
* * %-EINVAL - If @type is invalid.
*/
-int misc_cg_set_capacity(enum misc_res_type type, unsigned long capacity)
+int misc_cg_set_capacity(enum misc_res_type type, u64 capacity)
{
if (!valid_type(type))
return -EINVAL;
@@ -114,9 +114,9 @@ EXPORT_SYMBOL_GPL(misc_cg_set_capacity);
* Context: Any context.
*/
static void misc_cg_cancel_charge(enum misc_res_type type, struct misc_cg *cg,
- unsigned long amount)
+ u64 amount)
{
- WARN_ONCE(atomic_long_add_negative(-amount, &cg->res[type].usage),
+ WARN_ONCE(atomic64_add_negative(-amount, &cg->res[type].usage),
"misc cgroup resource %s became less than 0",
misc_res_name[type]);
}
@@ -138,12 +138,12 @@ static void misc_cg_cancel_charge(enum misc_res_type type, struct misc_cg *cg,
* capacity.
*/
int misc_cg_try_charge(enum misc_res_type type, struct misc_cg *cg,
- unsigned long amount)
+ u64 amount)
{
struct misc_cg *i, *j;
int ret;
struct misc_res *res;
- long new_usage;
+ s64 new_usage;

if (!(valid_type(type) && cg && READ_ONCE(misc_res_capacity[type])))
return -EINVAL;
@@ -154,7 +154,7 @@ int misc_cg_try_charge(enum misc_res_type type, struct misc_cg *cg,
for (i = cg; i; i = parent_misc(i)) {
res = &i->res[type];

- new_usage = atomic_long_add_return(amount, &res->usage);
+ new_usage = atomic64_add_return(amount, &res->usage);
if (new_usage > READ_ONCE(res->max) ||
new_usage > READ_ONCE(misc_res_capacity[type]) ||
new_usage < 0) {
@@ -166,7 +166,7 @@ int misc_cg_try_charge(enum misc_res_type type, struct misc_cg *cg,

err_charge:
for (j = i; j; j = parent_misc(j)) {
- atomic_long_inc(&j->res[type].events);
+ atomic64_inc(&j->res[type].events);
cgroup_file_notify(&j->events_file);
}

@@ -186,7 +186,7 @@ EXPORT_SYMBOL_GPL(misc_cg_try_charge);
* Context: Any context.
*/
void misc_cg_uncharge(enum misc_res_type type, struct misc_cg *cg,
- unsigned long amount)
+ u64 amount)
{
struct misc_cg *i;

@@ -210,7 +210,7 @@ static int misc_cg_max_show(struct seq_file *sf, void *v)
{
int i;
struct misc_cg *cg = css_misc(seq_css(sf));
- unsigned long max;
+ u64 max;

for (i = 0; i < MISC_CG_RES_TYPES; i++) {
if (READ_ONCE(misc_res_capacity[i])) {
@@ -218,7 +218,7 @@ static int misc_cg_max_show(struct seq_file *sf, void *v)
if (max == MAX_NUM)
seq_printf(sf, "%s max\n", misc_res_name[i]);
else
- seq_printf(sf, "%s %lu\n", misc_res_name[i],
+ seq_printf(sf, "%s %llu\n", misc_res_name[i],
max);
}
}
@@ -242,13 +242,13 @@ static int misc_cg_max_show(struct seq_file *sf, void *v)
* Return:
* * >= 0 - Number of bytes processed in the input.
* * -EINVAL - If buf is not valid.
- * * -ERANGE - If number is bigger than the unsigned long capacity.
+ * * -ERANGE - If number is bigger than the u64 capacity.
*/
static ssize_t misc_cg_max_write(struct kernfs_open_file *of, char *buf,
size_t nbytes, loff_t off)
{
struct misc_cg *cg;
- unsigned long max;
+ u64 max;
int ret = 0, i;
enum misc_res_type type = MISC_CG_RES_TYPES;
char *token;
@@ -272,7 +272,7 @@ static ssize_t misc_cg_max_write(struct kernfs_open_file *of, char *buf,
if (!strcmp(MAX_STR, buf)) {
max = MAX_NUM;
} else {
- ret = kstrtoul(buf, 0, &max);
+ ret = kstrtou64(buf, 0, &max);
if (ret)
return ret;
}
@@ -298,13 +298,13 @@ static ssize_t misc_cg_max_write(struct kernfs_open_file *of, char *buf,
static int misc_cg_current_show(struct seq_file *sf, void *v)
{
int i;
- unsigned long usage;
+ u64 usage;
struct misc_cg *cg = css_misc(seq_css(sf));

for (i = 0; i < MISC_CG_RES_TYPES; i++) {
- usage = atomic_long_read(&cg->res[i].usage);
+ usage = atomic64_read(&cg->res[i].usage);
if (READ_ONCE(misc_res_capacity[i]) || usage)
- seq_printf(sf, "%s %lu\n", misc_res_name[i], usage);
+ seq_printf(sf, "%s %llu\n", misc_res_name[i], usage);
}

return 0;
@@ -323,12 +323,12 @@ static int misc_cg_current_show(struct seq_file *sf, void *v)
static int misc_cg_capacity_show(struct seq_file *sf, void *v)
{
int i;
- unsigned long cap;
+ u64 cap;

for (i = 0; i < MISC_CG_RES_TYPES; i++) {
cap = READ_ONCE(misc_res_capacity[i]);
if (cap)
- seq_printf(sf, "%s %lu\n", misc_res_name[i], cap);
+ seq_printf(sf, "%s %llu\n", misc_res_name[i], cap);
}

return 0;
@@ -337,12 +337,13 @@ static int misc_cg_capacity_show(struct seq_file *sf, void *v)
static int misc_events_show(struct seq_file *sf, void *v)
{
struct misc_cg *cg = css_misc(seq_css(sf));
- unsigned long events, i;
+ u64 events;
+ int i;

for (i = 0; i < MISC_CG_RES_TYPES; i++) {
- events = atomic_long_read(&cg->res[i].events);
+ events = atomic64_read(&cg->res[i].events);
if (READ_ONCE(misc_res_capacity[i]) || events)
- seq_printf(sf, "%s.max %lu\n", misc_res_name[i], events);
+ seq_printf(sf, "%s.max %llu\n", misc_res_name[i], events);
}
return 0;
}
@@ -399,7 +400,7 @@ misc_cg_alloc(struct cgroup_subsys_state *parent_css)

for (i = 0; i < MISC_CG_RES_TYPES; i++) {
WRITE_ONCE(cg->res[i].max, MAX_NUM);
- atomic_long_set(&cg->res[i].usage, 0);
+ atomic64_set(&cg->res[i].usage, 0);
}

return &cg->css;
--
2.25.1