Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Mon, 15 May 2023 18:30:17 -0300
From:   Arnaldo Carvalho de Melo <acme@kernel.org>
To:     Changbin Du <changbin.du@huawei.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
        Ian Rogers <irogers@google.com>,
        Adrian Hunter <adrian.hunter@intel.com>,
        linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] perf: ftrace: flush output after each writing
Message-ID: <ZGKkaROtXT9Wq2ai@kernel.org>
References: <20230513074000.733550-1-changbin.du@huawei.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20230513074000.733550-1-changbin.du@huawei.com>
Precedence: bulk

Em Sat, May 13, 2023 at 03:40:00PM +0800, Changbin Du escreveu:
> The pager will result stdout in full buffering mode instead of line
> buffering. We need to make the trace visible timely.

Thanks, applied.

- Arnaldo

 
> Signed-off-by: Changbin Du <changbin.du@huawei.com>
> ---
>  tools/perf/builtin-ftrace.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
> index 810e3376c7d6..ad2a9ae041f6 100644
> --- a/tools/perf/builtin-ftrace.c
> +++ b/tools/perf/builtin-ftrace.c
> @@ -650,6 +650,8 @@ static int __cmd_ftrace(struct perf_ftrace *ftrace)
>  				break;
>  			if (fwrite(buf, n, 1, stdout) != 1)
>  				break;
> +			/* flush output since stdout is in full buffering mode due to pager */
> +			fflush(stdout);
>  		}
>  	}
>  
> -- 
> 2.25.1
> 

-- 

- Arnaldo