Message ID | 20240614081956.19832-8-johannes@sipsolutions.net |
---|---|
State | New |
Headers | show |
Series | tracing: improve symbolic printing | expand |
On Fri, 2024-06-14 at 10:19 +0200, Johannes Berg wrote: > From: Johannes Berg <johannes.berg@intel.com> > > The __print_symbolic() could only ever print the core > drop reasons, since that's the way the infrastructure > works. Now that we have __print_sym() with all the > advantages mentioned in that commit, convert to that > and get all the drop reasons from all subsystems. As > we already have a list of them, that's really easy. > > This is a little bit of .text (~100 bytes in my build) > and saves a lot of .data (~17k). > > Signed-off-by: Johannes Berg <johannes.berg@intel.com> > --- > include/net/dropreason.h | 5 +++++ > include/trace/events/skb.h | 16 +++----------- > net/core/skbuff.c | 43 ++++++++++++++++++++++++++++++++++++++ > 3 files changed, 51 insertions(+), 13 deletions(-) > > diff --git a/include/net/dropreason.h b/include/net/dropreason.h > index 56cb7be92244..c157070b5303 100644 > --- a/include/net/dropreason.h > +++ b/include/net/dropreason.h > @@ -42,6 +42,11 @@ struct drop_reason_list { > extern const struct drop_reason_list __rcu * > drop_reasons_by_subsys[SKB_DROP_REASON_SUBSYS_NUM]; > > +#ifdef CONFIG_TRACEPOINTS > +const char *drop_reason_lookup(unsigned long long value); > +void drop_reason_show(struct seq_file *m); > +#endif > + > void drop_reasons_register_subsys(enum skb_drop_reason_subsys subsys, > const struct drop_reason_list *list); > void drop_reasons_unregister_subsys(enum skb_drop_reason_subsys subsys); > diff --git a/include/trace/events/skb.h b/include/trace/events/skb.h > index 07e0715628ec..8a1a63f9e796 100644 > --- a/include/trace/events/skb.h > +++ b/include/trace/events/skb.h > @@ -8,15 +8,9 @@ > #include <linux/skbuff.h> > #include <linux/netdevice.h> > #include <linux/tracepoint.h> > +#include <net/dropreason.h> > > -#undef FN > -#define FN(reason) TRACE_DEFINE_ENUM(SKB_DROP_REASON_##reason); > -DEFINE_DROP_REASON(FN, FN) > - > -#undef FN > -#undef FNe > -#define FN(reason) { SKB_DROP_REASON_##reason, #reason }, > -#define FNe(reason) { SKB_DROP_REASON_##reason, #reason } > +TRACE_DEFINE_SYM_FNS(drop_reason, drop_reason_lookup, drop_reason_show); > > /* > * Tracepoint for free an sk_buff: > @@ -44,13 +38,9 @@ TRACE_EVENT(kfree_skb, > > TP_printk("skbaddr=%p protocol=%u location=%pS reason: %s", > __entry->skbaddr, __entry->protocol, __entry->location, > - __print_symbolic(__entry->reason, > - DEFINE_DROP_REASON(FN, FNe))) > + __print_sym(__entry->reason, drop_reason )) Minor nit: if you have to repost for other reasons, ^^ here checkpatch complains for the extra space. Otherwise LGTM, Thanks! Paolo
diff --git a/include/net/dropreason.h b/include/net/dropreason.h index 56cb7be92244..c157070b5303 100644 --- a/include/net/dropreason.h +++ b/include/net/dropreason.h @@ -42,6 +42,11 @@ struct drop_reason_list { extern const struct drop_reason_list __rcu * drop_reasons_by_subsys[SKB_DROP_REASON_SUBSYS_NUM]; +#ifdef CONFIG_TRACEPOINTS +const char *drop_reason_lookup(unsigned long long value); +void drop_reason_show(struct seq_file *m); +#endif + void drop_reasons_register_subsys(enum skb_drop_reason_subsys subsys, const struct drop_reason_list *list); void drop_reasons_unregister_subsys(enum skb_drop_reason_subsys subsys); diff --git a/include/trace/events/skb.h b/include/trace/events/skb.h index 07e0715628ec..8a1a63f9e796 100644 --- a/include/trace/events/skb.h +++ b/include/trace/events/skb.h @@ -8,15 +8,9 @@ #include <linux/skbuff.h> #include <linux/netdevice.h> #include <linux/tracepoint.h> +#include <net/dropreason.h> -#undef FN -#define FN(reason) TRACE_DEFINE_ENUM(SKB_DROP_REASON_##reason); -DEFINE_DROP_REASON(FN, FN) - -#undef FN -#undef FNe -#define FN(reason) { SKB_DROP_REASON_##reason, #reason }, -#define FNe(reason) { SKB_DROP_REASON_##reason, #reason } +TRACE_DEFINE_SYM_FNS(drop_reason, drop_reason_lookup, drop_reason_show); /* * Tracepoint for free an sk_buff: @@ -44,13 +38,9 @@ TRACE_EVENT(kfree_skb, TP_printk("skbaddr=%p protocol=%u location=%pS reason: %s", __entry->skbaddr, __entry->protocol, __entry->location, - __print_symbolic(__entry->reason, - DEFINE_DROP_REASON(FN, FNe))) + __print_sym(__entry->reason, drop_reason )) ); -#undef FN -#undef FNe - TRACE_EVENT(consume_skb, TP_PROTO(struct sk_buff *skb, void *location), diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 466999a7515e..cd1ea6c3e0f8 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -145,6 +145,49 @@ drop_reasons_by_subsys[SKB_DROP_REASON_SUBSYS_NUM] = { }; EXPORT_SYMBOL(drop_reasons_by_subsys); +#ifdef CONFIG_TRACEPOINTS +const char *drop_reason_lookup(unsigned long long value) +{ + unsigned long long subsys_id = value >> SKB_DROP_REASON_SUBSYS_SHIFT; + u32 reason = value & ~SKB_DROP_REASON_SUBSYS_MASK; + const struct drop_reason_list *subsys; + + if (subsys_id >= SKB_DROP_REASON_SUBSYS_NUM) + return NULL; + + subsys = rcu_dereference(drop_reasons_by_subsys[subsys_id]); + if (!subsys) + return NULL; + if (reason >= subsys->n_reasons) + return NULL; + return subsys->reasons[reason]; +} + +void drop_reason_show(struct seq_file *m) +{ + u32 subsys_id; + + rcu_read_lock(); + for (subsys_id = 0; subsys_id < SKB_DROP_REASON_SUBSYS_NUM; subsys_id++) { + const struct drop_reason_list *subsys; + u32 i; + + subsys = rcu_dereference(drop_reasons_by_subsys[subsys_id]); + if (!subsys) + continue; + + for (i = 0; i < subsys->n_reasons; i++) { + if (!subsys->reasons[i]) + continue; + seq_printf(m, ", { %u, \"%s\" }", + (subsys_id << SKB_DROP_REASON_SUBSYS_SHIFT) | i, + subsys->reasons[i]); + } + } + rcu_read_unlock(); +} +#endif + /** * drop_reasons_register_subsys - register another drop reason subsystem * @subsys: the subsystem to register, must not be the core