From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7FAF72EBBA8; Wed, 8 Oct 2025 15:22:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759936946; cv=none; b=ADQgEQODswgLlM4IxFf0Dlje2KHflcOdGfLLES+aUdW3R+0NNubqU12xsMeLDTX69aQRuyxPip8/GlMMHgrebj0UI671vIcXfxQuBcb05kASHAxKqcHkaVOEm3Y8MB0b0DlH58Roql1hJzf0dw8g3XXlq0u2z+57Z0hCtlUwxAs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759936946; c=relaxed/simple; bh=uS3x5HWfAOiuRhFovDGOd4azvewpNkYCCS1T7U+icyc=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=h2jrS7EwOXs9CT9QxvIRM86SicQkPUp3YczhH/9uSYNgIsgXUv1MJsvt/roFr6faQlE9bmg6td5VFBaHATB2KZfp0VA/fQCkPdWG/bCpFdsoTv8R78OIQWX0UgTN0iKOtSTBtgYhf4N1fxznedliVGsuVwvyVGEN+8MWur74AEM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Received: from omf08.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 14B1059C33; Wed, 8 Oct 2025 15:22:22 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf08.hostedemail.com (Postfix) with ESMTPA id 60EE820027; Wed, 8 Oct 2025 15:22:20 +0000 (UTC) Date: Wed, 8 Oct 2025 11:24:14 -0400 From: Steven Rostedt To: Sasha Levin Cc: mhiramat@kernel.org, mathieu.desnoyers@efficios.com, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] tracing/wakeup: Balance prolog on fgraph failure Message-ID: <20251008112414.03d5d803@gandalf.local.home> In-Reply-To: <20251006175848.1906912-1-sashal@kernel.org> References: <20251006175848.1906912-1-sashal@kernel.org> X-Mailer: Claws Mail 3.20.0git84 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: 17kdbnhybw7bnke7y6eng9wjsuyocdu6 X-Rspamd-Server: rspamout05 X-Rspamd-Queue-Id: 60EE820027 X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX188/wSdqsK8NGl+nzxPL4f8OR7UbtW6K1k= X-HE-Tag: 1759936940-26348 X-HE-Meta: U2FsdGVkX1/kJOAgpGVnRSE9d8qFQiwJUCu0rhghrtYYotvpAia6E1zbI1Fsq00UUJGL0aMt1UUv+B1Q0y/6QnGS8kRpfRLjvHoKZb1Q8sskVOJOscRxVRSqxfOlcXOTvjow2xa/+6daFEynqCmgKR8NJg1BwxA1rTJCQX+1pL4eFaKWa8YaOsM+z+Gyuxx0hqsXQgs2PV53fb3lUAZ3oqTlA7ynk3B0DM1Jvab2ODG3XDp+iQc+H6Kdd7vcZSLWvnUf/mFbQ7vZkqixWnlI6b+Cd0zhTAFeKdHMb9lXSp3yP3eYINx+AuCW70aqvcUp+LW7rfhe6Nuyrf9CoOh6feUmboWLXRUu On Mon, 6 Oct 2025 13:58:47 -0400 Sasha Levin wrote: > diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c > index bf1cb80742aed..fa48bbdf0851c 100644 > --- a/kernel/trace/trace_sched_wakeup.c > +++ b/kernel/trace/trace_sched_wakeup.c > @@ -138,8 +138,11 @@ static int wakeup_graph_entry(struct ftrace_graph_ent *trace, > return 0; > > calltime = fgraph_reserve_data(gops->idx, sizeof(*calltime)); > - if (!calltime) > + if (!calltime) { > + local_dec(&data->disabled); > + preempt_enable_notrace(); > return 0; > + } > > *calltime = trace_clock_local(); > > @@ -169,8 +172,11 @@ static void wakeup_graph_return(struct ftrace_graph_ret *trace, > rettime = trace_clock_local(); > > calltime = fgraph_retrieve_data(gops->idx, &size); > - if (!calltime) > + if (!calltime) { > + local_dec(&data->disabled); > + preempt_enable_notrace(); > return; > + } > > __trace_graph_return(tr, trace, trace_ctx, *calltime, rettime); > local_dec(&data->disabled); Technically correct, but this would look better: diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c index bf1cb80742ae..e3f2e4f56faa 100644 --- a/kernel/trace/trace_sched_wakeup.c +++ b/kernel/trace/trace_sched_wakeup.c @@ -138,12 +138,10 @@ static int wakeup_graph_entry(struct ftrace_graph_ent *trace, return 0; calltime = fgraph_reserve_data(gops->idx, sizeof(*calltime)); - if (!calltime) - return 0; - - *calltime = trace_clock_local(); - - ret = __trace_graph_entry(tr, trace, trace_ctx); + if (calltime) { + *calltime = trace_clock_local(); + ret = __trace_graph_entry(tr, trace, trace_ctx); + } local_dec(&data->disabled); preempt_enable_notrace(); @@ -169,12 +167,10 @@ static void wakeup_graph_return(struct ftrace_graph_ret *trace, rettime = trace_clock_local(); calltime = fgraph_retrieve_data(gops->idx, &size); - if (!calltime) - return; + if (calltime) + __trace_graph_return(tr, trace, trace_ctx, *calltime, rettime); - __trace_graph_return(tr, trace, trace_ctx, *calltime, rettime); local_dec(&data->disabled); - preempt_enable_notrace(); return; } -- Steve