From 135746c61fa6d7f66dc079027304eaa4d35fe942 Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Tue, 7 Feb 2023 19:44:55 +0100 Subject: [PATCH] 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 Reviewed-by: Simon Horman Reviewed-by: Eric Dumazet Signed-off-by: Jakub Kicinski --- net/core/sysctl_net_core.c | 46 +++++++++++++++++++++++--------------- 1 file changed, 28 insertions(+), 18 deletions(-) diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c index e7b98162c632..6935ecdc84b0 100644 --- a/net/core/sysctl_net_core.c +++ b/net/core/sysctl_net_core.c @@ -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: