net-sysctl: factor out cpumask parsing helper

Will be used by the following patch to avoid code
duplication. No functional changes intended.

The only difference is that now flow_limit_cpu_sysctl() will
always compute the flow limit mask on each read operation,
even when read() will not return any byte to user-space.

Note that the new helper is placed under a new #ifdef at
the file start to better fit the usage in the later patch

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Paolo Abeni 2023-02-07 19:44:55 +01:00 committed by Jakub Kicinski
parent 8697a258ae
commit 135746c61f

View File

@ -45,6 +45,33 @@ EXPORT_SYMBOL(sysctl_fb_tunnels_only_for_init_net);
int sysctl_devconf_inherit_init_net __read_mostly;
EXPORT_SYMBOL(sysctl_devconf_inherit_init_net);
#if IS_ENABLED(CONFIG_NET_FLOW_LIMIT)
static void dump_cpumask(void *buffer, size_t *lenp, loff_t *ppos,
struct cpumask *mask)
{
char kbuf[128];
int len;
if (*ppos || !*lenp) {
*lenp = 0;
return;
}
len = min(sizeof(kbuf) - 1, *lenp);
len = scnprintf(kbuf, len, "%*pb", cpumask_pr_args(mask));
if (!len) {
*lenp = 0;
return;
}
if (len < *lenp)
kbuf[len++] = '\n';
memcpy(buffer, kbuf, len);
*lenp = len;
*ppos += len;
}
#endif
#ifdef CONFIG_RPS
static int rps_sock_flow_sysctl(struct ctl_table *table, int write,
void *buffer, size_t *lenp, loff_t *ppos)
@ -155,13 +182,6 @@ static int flow_limit_cpu_sysctl(struct ctl_table *table, int write,
write_unlock:
mutex_unlock(&flow_limit_update_mutex);
} else {
char kbuf[128];
if (*ppos || !*lenp) {
*lenp = 0;
goto done;
}
cpumask_clear(mask);
rcu_read_lock();
for_each_possible_cpu(i) {
@ -171,17 +191,7 @@ write_unlock:
}
rcu_read_unlock();
len = min(sizeof(kbuf) - 1, *lenp);
len = scnprintf(kbuf, len, "%*pb", cpumask_pr_args(mask));
if (!len) {
*lenp = 0;
goto done;
}
if (len < *lenp)
kbuf[len++] = '\n';
memcpy(buffer, kbuf, len);
*lenp = len;
*ppos += len;
dump_cpumask(buffer, lenp, ppos, mask);
}
done: