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[79.23.205.114]) by smtp.gmail.com with ESMTPSA id rl12sm114523ejb.94.2021.06.08.10.17.55 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 08 Jun 2021 10:17:56 -0700 (PDT) Subject: Re: [PATCH V3 8/9] tracing: Add osnoise tracer To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, Phil Auld , Sebastian Andrzej Siewior , Kate Carcia , Jonathan Corbet , Ingo Molnar , Peter Zijlstra , Thomas Gleixner , Alexandre Chartre , Clark Willaims , John Kacur , Juri Lelli , linux-doc@vger.kernel.org References: <20210604172803.527aa070@oasis.local.home> From: Daniel Bristot de Oliveira Message-ID: Date: Tue, 8 Jun 2021 19:17:55 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: <20210604172803.527aa070@oasis.local.home> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On 6/4/21 11:28 PM, Steven Rostedt wrote: >> + /* >> + * This is an evidence of race conditions that cause >> + * a value to be "discounted" too much. >> + */ >> + if (duration < 0) >> + pr_err("int safe negative!\n"); > Probably want to have this happen at most once a run. If something were > to break, I don't think we want this to live lock the machine doing > tons of prints. We could have a variable stored on the > osnoise_variables that states this was printed. Check that variable to > see if it wasn't printed during a run (when current_tracer was set), > and print only once if it is. I created a "bool tainted" variable, that is set true if any problem with time() related functions happen. I will pr_warn that there is a problem on _start(), but also print this info at the top of the tracer header, so it is clear also from the trace output. Thoughts? -- Daniel