From: Peter Zijlstra <peterz@infradead.org>
To: mingo@kernel.org
Cc: mark.rutland@arm.com, juri.lelli@redhat.com,
daniel.lezcano@linaro.org, wanpengli@tencent.com,
kvm@vger.kernel.org, rafael@kernel.org, peterz@infradead.org,
dave.hansen@linux.intel.com,
virtualization@lists.linux-foundation.org, bsegall@google.com,
amakhalov@vmware.com, will@kernel.org, tglx@linutronix.de,
vschneid@redhat.com, hpa@zytor.com, x86@kernel.org,
pv-drivers@vmware.com, mgorman@suse.de,
linux-trace-kernel@vger.kernel.org, linux-pm@vger.kernel.org,
boqun.feng@gmail.com, rostedt@goodmis.org, bp@alien8.de,
vincent.guittot@linaro.org, boris.ostrovsky@oracle.com,
dietmar.eggemann@arm.com, jgross@suse.com, seanjc@google.com,
linux-kernel@vger.kernel.org, mhiramat@kernel.org,
pbonzini@redhat.com, bristot@redhat.com
Subject: [PATCH 3/6] ftrace/x86: Warn and ignore graph tracing when RCU is disabled
Date: Mon, 23 Jan 2023 21:50:12 +0100 [thread overview]
Message-ID: <20230123205515.059999893@infradead.org> (raw)
In-Reply-To: 20230123205009.790550642@infradead.org
All RCU disabled code should be noinstr and hence we should never get
here -- when we do, WARN about it and make sure to not actually do
tracing.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
arch/x86/kernel/ftrace.c | 3 +++
1 file changed, 3 insertions(+)
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -646,6 +646,9 @@ void prepare_ftrace_return(unsigned long
if (unlikely(atomic_read(¤t->tracing_graph_pause)))
return;
+ if (WARN_ONCE(!rcu_is_watching(), "RCU not on for: %pS\n", (void *)ip))
+ return;
+
bit = ftrace_test_recursion_trylock(ip, *parent);
if (bit < 0)
return;
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
next prev parent reply other threads:[~2023-01-23 20:58 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-01-23 20:50 [PATCH 0/6] A few cpuidle vs rcu fixes Peter Zijlstra
2023-01-23 20:50 ` [PATCH 1/6] x86: Always inline arch_atomic64 Peter Zijlstra
2023-01-23 20:50 ` [PATCH 2/6] x86/pvclock: improve atomic update of last_value in pvclock_clocksource_read Peter Zijlstra
2023-01-23 20:50 ` Peter Zijlstra [this message]
2023-01-23 21:53 ` [PATCH 3/6] ftrace/x86: Warn and ignore graph tracing when RCU is disabled Steven Rostedt
2023-01-23 22:07 ` Steven Rostedt
2023-01-24 14:44 ` Peter Zijlstra
2023-01-24 17:12 ` Mark Rutland
2023-01-25 9:37 ` Peter Zijlstra
2023-01-25 10:47 ` Peter Zijlstra
2023-01-25 11:32 ` Mark Rutland
[not found] ` <20230125184658.GL2948950@paulmck-ThinkPad-P17-Gen-1>
2023-01-26 9:28 ` Peter Zijlstra
2023-01-23 20:50 ` [PATCH 4/6] x86: Mark sched_clock() noinstr Peter Zijlstra
2023-01-23 20:50 ` [PATCH 5/6] sched/clock: Make local_clock() noinstr Peter Zijlstra
2023-01-23 20:50 ` [PATCH 6/6] cpuidle: Fix poll_idle() noinstr annotation Peter Zijlstra
2023-01-24 14:24 ` Rafael J. Wysocki
2023-01-24 16:34 ` [PATCH 0/6] A few cpuidle vs rcu fixes Mark Rutland
2023-01-24 17:30 ` Mark Rutland
2023-01-24 18:39 ` Mark Rutland
2023-01-25 9:35 ` Peter Zijlstra
2023-01-25 9:40 ` Peter Zijlstra
2023-01-25 10:23 ` Mark Rutland
2023-01-25 9:31 ` Peter Zijlstra
2023-01-25 9:36 ` Mark Rutland
2023-01-25 15:20 ` Mark Rutland
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20230123205515.059999893@infradead.org \
--to=peterz@infradead.org \
--cc=amakhalov@vmware.com \
--cc=boqun.feng@gmail.com \
--cc=boris.ostrovsky@oracle.com \
--cc=bp@alien8.de \
--cc=bristot@redhat.com \
--cc=bsegall@google.com \
--cc=daniel.lezcano@linaro.org \
--cc=dave.hansen@linux.intel.com \
--cc=dietmar.eggemann@arm.com \
--cc=hpa@zytor.com \
--cc=jgross@suse.com \
--cc=juri.lelli@redhat.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=linux-trace-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=mgorman@suse.de \
--cc=mhiramat@kernel.org \
--cc=mingo@kernel.org \
--cc=pbonzini@redhat.com \
--cc=pv-drivers@vmware.com \
--cc=rafael@kernel.org \
--cc=rostedt@goodmis.org \
--cc=seanjc@google.com \
--cc=tglx@linutronix.de \
--cc=vincent.guittot@linaro.org \
--cc=virtualization@lists.linux-foundation.org \
--cc=vschneid@redhat.com \
--cc=wanpengli@tencent.com \
--cc=will@kernel.org \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).