From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 8879A12E51; Sat, 24 Feb 2024 04:15:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708748146; cv=none; b=m/UMa85zbxbZlYGn6xd3y/KFI1twOLiw47M1G8F/Cf2P7rBH/1MQVwOQxqwQWEfB+NNGlk13CtqRecsZOP99f+6lnUzF4Oa6SzgSEw3jgZmB+pZE63Y3UZZSKHfUJm9ftnfuS2W+laqzY5vvOwm7OGQPAAbOmuk0cBRLBZPx9RI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708748146; c=relaxed/simple; bh=Y1QHX51XD00kV5oc4mKEfXtZpXu11m0GfYW/q0nli28=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=luq48E6EEnkDPyeKm2mBxjjLJtoX+Tta6HsSUi9Ix7EfR2m0F387UVivJ1lCDjKjOVVcTueCfBAM8hOP4J+vGoYyvYXJUbbZgvTi5FLJnRQTDiFMGqmDpsqEsqQ9PGBUu9ApQzwkd+UukyGaeL22qaYtMygOO9ESgrKpS50Mp7k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=QrW/X6P9; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="QrW/X6P9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A2109C433C7; Sat, 24 Feb 2024 04:15:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1708748145; bh=Y1QHX51XD00kV5oc4mKEfXtZpXu11m0GfYW/q0nli28=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=QrW/X6P9cy1P94wJNK9yiOk7VMZJucfVbOvymRcirzT0mTM5xnrFHHn6DH+2gVN+x J9IBr0xlvmaK0KTQjtZsDag0A3an0QTAfdZtPCDcaHQKGJ0G27Sq3ElT8LXjNlcN/K Nf4AkRRcNnvP5g8QmoJw55QwjjKr8NZPXrhC2iNCseM6XfmNxI67/gQRu6KYu9/KSr /UrHpi/cY/jhCpb7DUpXFS/51PIf4ixGisfiO/DSzPnMG4EFu6X0+Xw8uNVcXeM+1z OZP1i7DR7j19lAU0I9u2MrhbYtpYnwTP174vISnubdATWTvyOk79tYgYhSrqGT/uad uuLR5UxxgXm2A== Date: Fri, 23 Feb 2024 20:15:45 -0800 From: "Darrick J. Wong" To: akpm@linux-foundation.org, daniel@gluo.nz, kent.overstreet@linux.dev Cc: linux-xfs@vger.kernel.org, linux-bcachefs@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 09/10] time_stats: report information in json format Message-ID: <20240224041545.GC616564@frogsfrogsfrogs> References: <170873667916.1860949.11027844260383646446.stgit@frogsfrogsfrogs> <170873668085.1860949.11659237532415596101.stgit@frogsfrogsfrogs> Precedence: bulk X-Mailing-List: linux-bcachefs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <170873668085.1860949.11659237532415596101.stgit@frogsfrogsfrogs> On Fri, Feb 23, 2024 at 05:12:26PM -0800, Darrick J. Wong wrote: > From: Darrick J. Wong > > Export json versions of time statistics information. Given the tabular > nature of the numbers exposed, this will make it a lot easier for higher > (than C) level languages (e.g. python) to import information without > needing to write yet another clumsy string parser. > > Signed-off-by: Darrick J. Wong > Signed-off-by: Kent Overstreet > --- > include/linux/time_stats.h | 2 + > lib/time_stats.c | 87 ++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 89 insertions(+) > > > diff --git a/include/linux/time_stats.h b/include/linux/time_stats.h > index b3c810fff963a..4e1f5485ed039 100644 > --- a/include/linux/time_stats.h > +++ b/include/linux/time_stats.h > @@ -156,6 +156,8 @@ static inline bool track_event_change(struct time_stats *stats, bool v) > struct seq_buf; > void time_stats_to_seq_buf(struct seq_buf *, struct time_stats *, > const char *epoch_name, unsigned int flags); > +void time_stats_to_json(struct seq_buf *, struct time_stats *, > + const char *epoch_name, unsigned int flags); > > void time_stats_exit(struct time_stats *); > void time_stats_init(struct time_stats *); > diff --git a/lib/time_stats.c b/lib/time_stats.c > index 0fb3d854e503b..c0f209dd9f6dd 100644 > --- a/lib/time_stats.c > +++ b/lib/time_stats.c > @@ -266,6 +266,93 @@ void time_stats_to_seq_buf(struct seq_buf *out, struct time_stats *stats, > } > EXPORT_SYMBOL_GPL(time_stats_to_seq_buf); > > +void time_stats_to_json(struct seq_buf *out, struct time_stats *stats, > + const char *epoch_name, unsigned int flags) > +{ > + struct quantiles *quantiles = time_stats_to_quantiles(stats); > + s64 f_mean = 0, d_mean = 0; > + u64 f_stddev = 0, d_stddev = 0; > + > + if (stats->buffer) { > + int cpu; > + > + spin_lock_irq(&stats->lock); > + for_each_possible_cpu(cpu) > + __time_stats_clear_buffer(stats, per_cpu_ptr(stats->buffer, cpu)); > + spin_unlock_irq(&stats->lock); > + } > + > + if (stats->freq_stats.n) { > + /* avoid divide by zero */ > + f_mean = mean_and_variance_get_mean(stats->freq_stats); > + f_stddev = mean_and_variance_get_stddev(stats->freq_stats); > + d_mean = mean_and_variance_get_mean(stats->duration_stats); > + d_stddev = mean_and_variance_get_stddev(stats->duration_stats); > + } else if (flags & TIME_STATS_PRINT_NO_ZEROES) { > + /* unless we didn't want zeroes anyway */ > + return; > + } > + > + seq_buf_printf(out, "{\n"); > + seq_buf_printf(out, " \"epoch\": \"%s\",\n", epoch_name); > + seq_buf_printf(out, " \"count\": %llu,\n", stats->duration_stats.n); > + > + seq_buf_printf(out, " \"duration_ns\": {\n"); > + seq_buf_printf(out, " \"min\": %llu,\n", stats->min_duration); > + seq_buf_printf(out, " \"max\": %llu,\n", stats->max_duration); > + seq_buf_printf(out, " \"total\": %llu,\n", stats->total_duration); > + seq_buf_printf(out, " \"mean\": %llu,\n", d_mean); > + seq_buf_printf(out, " \"stddev\": %llu\n", d_stddev); > + seq_buf_printf(out, " },\n"); > + > + d_mean = mean_and_variance_weighted_get_mean(stats->duration_stats_weighted, TIME_STATS_MV_WEIGHT); > + d_stddev = mean_and_variance_weighted_get_stddev(stats->duration_stats_weighted, TIME_STATS_MV_WEIGHT); > + > + seq_buf_printf(out, " \"duration_ewma_ns\": {\n"); > + seq_buf_printf(out, " \"mean\": %llu,\n", d_mean); > + seq_buf_printf(out, " \"stddev\": %llu\n", d_stddev); > + seq_buf_printf(out, " },\n"); > + > + seq_buf_printf(out, " \"frequency_ns\": {\n"); I took the variable names too literally here; these labels really ought to be "between_ns" and "between_ewma_ns" to maintain consistency with the labels in the table format. > + seq_buf_printf(out, " \"min\": %llu,\n", stats->min_freq); > + seq_buf_printf(out, " \"max\": %llu,\n", stats->max_freq); > + seq_buf_printf(out, " \"mean\": %llu,\n", f_mean); > + seq_buf_printf(out, " \"stddev\": %llu\n", f_stddev); > + seq_buf_printf(out, " },\n"); > + > + f_mean = mean_and_variance_weighted_get_mean(stats->freq_stats_weighted, TIME_STATS_MV_WEIGHT); > + f_stddev = mean_and_variance_weighted_get_stddev(stats->freq_stats_weighted, TIME_STATS_MV_WEIGHT); > + > + seq_buf_printf(out, " \"frequency_ewma_ns\": {\n"); > + seq_buf_printf(out, " \"mean\": %llu,\n", f_mean); > + seq_buf_printf(out, " \"stddev\": %llu\n", f_stddev); > + > + if (quantiles) { > + u64 last_q = 0; > + > + /* close frequency_ewma_ns but signal more items */ (also this comment) > + seq_buf_printf(out, " },\n"); > + > + seq_buf_printf(out, " \"quantiles_ns\": [\n"); > + eytzinger0_for_each(i, NR_QUANTILES) { > + bool is_last = eytzinger0_next(i, NR_QUANTILES) == -1; > + > + u64 q = max(quantiles->entries[i].m, last_q); > + seq_buf_printf(out, " %llu", q); > + if (!is_last) > + seq_buf_printf(out, ", "); > + last_q = q; > + } > + seq_buf_printf(out, " ]\n"); > + } else { > + /* close frequency_ewma_ns without dumping further */ (this one too) Kent, would you mind making that edit the next time you reflow your branch? --D > + seq_buf_printf(out, " }\n"); > + } > + > + seq_buf_printf(out, "}\n"); > +} > +EXPORT_SYMBOL_GPL(time_stats_to_json); > + > void time_stats_exit(struct time_stats *stats) > { > free_percpu(stats->buffer); > >