Merge branch 'for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup updates from Tejun Heo:
 "Documentation updates and the addition of cgroup_parse_float() which
  will be used by new controllers including blk-iocost"

* 'for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  docs: cgroup-v1: convert docs to ReST and rename to *.rst
  cgroup: Move cgroup_parse_float() implementation out of CONFIG_SYSFS
  cgroup: add cgroup_parse_float()
This commit is contained in:
Linus Torvalds
2019-07-08 21:35:12 -07:00
37 changed files with 989 additions and 627 deletions

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@@ -6240,6 +6240,48 @@ struct cgroup *cgroup_get_from_fd(int fd)
}
EXPORT_SYMBOL_GPL(cgroup_get_from_fd);
static u64 power_of_ten(int power)
{
u64 v = 1;
while (power--)
v *= 10;
return v;
}
/**
* cgroup_parse_float - parse a floating number
* @input: input string
* @dec_shift: number of decimal digits to shift
* @v: output
*
* Parse a decimal floating point number in @input and store the result in
* @v with decimal point right shifted @dec_shift times. For example, if
* @input is "12.3456" and @dec_shift is 3, *@v will be set to 12345.
* Returns 0 on success, -errno otherwise.
*
* There's nothing cgroup specific about this function except that it's
* currently the only user.
*/
int cgroup_parse_float(const char *input, unsigned dec_shift, s64 *v)
{
s64 whole, frac = 0;
int fstart = 0, fend = 0, flen;
if (!sscanf(input, "%lld.%n%lld%n", &whole, &fstart, &frac, &fend))
return -EINVAL;
if (frac < 0)
return -EINVAL;
flen = fend > fstart ? fend - fstart : 0;
if (flen < dec_shift)
frac *= power_of_ten(dec_shift - flen);
else
frac = DIV_ROUND_CLOSEST_ULL(frac, power_of_ten(flen - dec_shift));
*v = whole * power_of_ten(dec_shift) + frac;
return 0;
}
/*
* sock->sk_cgrp_data handling. For more info, see sock_cgroup_data
* definition in cgroup-defs.h.
@@ -6402,4 +6444,5 @@ static int __init cgroup_sysfs_init(void)
return sysfs_create_group(kernel_kobj, &cgroup_sysfs_attr_group);
}
subsys_initcall(cgroup_sysfs_init);
#endif /* CONFIG_SYSFS */

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@@ -729,7 +729,7 @@ static inline int nr_cpusets(void)
* load balancing domains (sched domains) as specified by that partial
* partition.
*
* See "What is sched_load_balance" in Documentation/cgroup-v1/cpusets.txt
* See "What is sched_load_balance" in Documentation/cgroup-v1/cpusets.rst
* for a background explanation of this.
*
* Does not return errors, on the theory that the callers of this