From 4b59a319ad29815aa8f629513df2c291c2108bf9 Mon Sep 17 00:00:00 2001
From: Kent Overstreet <kent.overstreet@gmail.com>
Date: Wed, 16 Feb 2022 00:42:34 -0500
Subject: [PATCH] bcachefs: Fix slow tracepoints
Some of our tracepoints were calling snprintf("pS") - which does symbol
table lookups - in TP_fast_assign(), which turns out to be a really bad
idea.
This was done because perf trace wasn't correctly printing tracepoints
that use %pS anymore - but it turns out trace-cmd does handle it
correctly.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
---
fs/bcachefs/trace.h | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/fs/bcachefs/trace.h b/fs/bcachefs/trace.h
index 5e78c396e24cc..64b7d9364fd91 100644
--- a/fs/bcachefs/trace.h
+++ b/fs/bcachefs/trace.h
@@ -358,7 +358,7 @@ TRACE_EVENT(btree_node_relock_fail,
TP_STRUCT__entry(
__array(char, trans_fn, 24 )
- __array(char, caller, 32 )
+ __field(unsigned long, caller_ip )
__field(u8, btree_id )
__field(u64, pos_inode )
__field(u64, pos_offset )
@@ -370,7 +370,7 @@ TRACE_EVENT(btree_node_relock_fail,
TP_fast_assign(
strncpy(__entry->trans_fn, trans_fn, sizeof(__entry->trans_fn));
- snprintf(__entry->caller, sizeof(__entry->caller), "%pS", (void *) caller_ip);
+ __entry->caller_ip = caller_ip;
__entry->btree_id = btree_id;
__entry->pos_inode = pos->inode;
__entry->pos_offset = pos->offset;
@@ -380,9 +380,9 @@ TRACE_EVENT(btree_node_relock_fail,
__entry->node_lock_seq = node_lock_seq;
),
- TP_printk("%s %s btree %u pos %llu:%llu:%u, node %lu iter seq %u lock seq %u",
+ TP_printk("%s %pS btree %u pos %llu:%llu:%u, node %lu iter seq %u lock seq %u",
__entry->trans_fn,
- __entry->caller,
+ (void *) __entry->caller_ip,
__entry->btree_id,
__entry->pos_inode,
__entry->pos_offset,
@@ -673,7 +673,7 @@ DECLARE_EVENT_CLASS(transaction_restart_iter,
TP_STRUCT__entry(
__array(char, trans_fn, 24 )
- __array(char, caller, 32 )
+ __field(unsigned long, caller_ip )
__field(u8, btree_id )
__field(u64, pos_inode )
__field(u64, pos_offset )
@@ -682,16 +682,16 @@ DECLARE_EVENT_CLASS(transaction_restart_iter,
TP_fast_assign(
strncpy(__entry->trans_fn, trans_fn, sizeof(__entry->trans_fn));
- snprintf(__entry->caller, sizeof(__entry->caller), "%pS", (void *) caller_ip);
+ __entry->caller_ip = caller_ip;
__entry->btree_id = btree_id;
__entry->pos_inode = pos->inode;
__entry->pos_offset = pos->offset;
__entry->pos_snapshot = pos->snapshot;
),
- TP_printk("%s %s btree %u pos %llu:%llu:%u",
+ TP_printk("%s %pS btree %u pos %llu:%llu:%u",
__entry->trans_fn,
- __entry->caller,
+ (void *) __entry->caller_ip,
__entry->btree_id,
__entry->pos_inode,
__entry->pos_offset,
--
2.30.2