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 B388B143C52; Thu, 13 Jun 2024 12:08:55 +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=1718280535; cv=none; b=C5FLPIzbJx8hWy4Usxb0SfIxpidCNVLkS7fhJTgxiy1XRbL77TP81xSIR+zbw0CRLqvUwhG7zrFsgg4H8UPrV5nbnUQ3XWWuNjLyW1LC3ofuaiL6Q81XVcFUtSSIB6AbITv8GpE0z1gejEtBM6/sQ5iQ6ze1Kobz8XmNT4l/bMM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718280535; c=relaxed/simple; bh=Mke7C7a7uMmWPFtgWo58HXCTQ2l1+Qif5CGvUkD8V9A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=trhkn7UT2MSsQWzVNYjB2boTNJ3ohMUrud+ZASClNxMYxi6jZJTjbzQFUBUKANFiqdHNdeZ3Ab1+CBusC6u4XECSneTq5rziabv7c0VAzEXEJuPPDVzGmoELM86/QgwC+Yfy5b/PbExHwleOh4dzuzk/oevVVOTxrKPWfA6E9T8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=jRvz551h; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="jRvz551h" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3EC0CC2BBFC; Thu, 13 Jun 2024 12:08:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1718280535; bh=Mke7C7a7uMmWPFtgWo58HXCTQ2l1+Qif5CGvUkD8V9A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jRvz551hEX5K2y0Pi2W4+xAu3NfD5bLbAaZOxL95I9wS+U8tcToZDxS6iBErfZYx+ PZaXsQJUJqZ6B9SCMtA7iybxQqVrNL91FUVN//2RbqhmNmblf8waIokyYaB6zlduGh ay/ygSyTPzoBHXPjZcWBO70v0cySIrfPc6igljAg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Daniel Bristot de Oliveria , John Kacur Subject: [PATCH 6.6 087/137] rtla/timerlat: Fix histogram report when a cpu count is 0 Date: Thu, 13 Jun 2024 13:34:27 +0200 Message-ID: <20240613113226.672397045@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240613113223.281378087@linuxfoundation.org> References: <20240613113223.281378087@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: John Kacur commit 01b05fc0e5f3aec443a9a8ffa0022cbca2fd3608 upstream. On short runs it is possible to get no samples on a cpu, like this: # rtla timerlat hist -u -T50 Index IRQ-001 Thr-001 Usr-001 IRQ-002 Thr-002 Usr-002 2 1 0 0 0 0 0 33 0 1 0 0 0 0 36 0 0 1 0 0 0 49 0 0 0 1 0 0 52 0 0 0 0 1 0 over: 0 0 0 0 0 0 count: 1 1 1 1 1 0 min: 2 33 36 49 52 18446744073709551615 avg: 2 33 36 49 52 - max: 2 33 36 49 52 0 rtla timerlat hit stop tracing IRQ handler delay: (exit from idle) 48.21 us (91.09 %) IRQ latency: 49.11 us Timerlat IRQ duration: 2.17 us (4.09 %) Blocking thread: 1.01 us (1.90 %) swapper/2:0 1.01 us ------------------------------------------------------------------------ Thread latency: 52.93 us (100%) Max timerlat IRQ latency from idle: 49.11 us in cpu 2 Note, the value 18446744073709551615 is the same as ~0. Fix this by reporting no results for the min, avg and max if the count is 0. Link: https://lkml.kernel.org/r/20240510190318.44295-1-jkacur@redhat.com Cc: stable@vger.kernel.org Fixes: 1eeb6328e8b3 ("rtla/timerlat: Add timerlat hist mode") Suggested-by: Daniel Bristot de Oliveria Signed-off-by: John Kacur Signed-off-by: Daniel Bristot de Oliveira Signed-off-by: Greg Kroah-Hartman --- tools/tracing/rtla/src/timerlat_hist.c | 68 ++++++++++++++++++++++----------- 1 file changed, 46 insertions(+), 22 deletions(-) --- a/tools/tracing/rtla/src/timerlat_hist.c +++ b/tools/tracing/rtla/src/timerlat_hist.c @@ -323,17 +323,29 @@ timerlat_print_summary(struct timerlat_h if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count) continue; - if (!params->no_irq) - trace_seq_printf(trace->seq, "%9llu ", - data->hist[cpu].min_irq); - - if (!params->no_thread) - trace_seq_printf(trace->seq, "%9llu ", - data->hist[cpu].min_thread); - - if (params->user_hist) - trace_seq_printf(trace->seq, "%9llu ", - data->hist[cpu].min_user); + if (!params->no_irq) { + if (data->hist[cpu].irq_count) + trace_seq_printf(trace->seq, "%9llu ", + data->hist[cpu].min_irq); + else + trace_seq_printf(trace->seq, " - "); + } + + if (!params->no_thread) { + if (data->hist[cpu].thread_count) + trace_seq_printf(trace->seq, "%9llu ", + data->hist[cpu].min_thread); + else + trace_seq_printf(trace->seq, " - "); + } + + if (params->user_hist) { + if (data->hist[cpu].user_count) + trace_seq_printf(trace->seq, "%9llu ", + data->hist[cpu].min_user); + else + trace_seq_printf(trace->seq, " - "); + } } trace_seq_printf(trace->seq, "\n"); @@ -383,17 +395,29 @@ timerlat_print_summary(struct timerlat_h if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count) continue; - if (!params->no_irq) - trace_seq_printf(trace->seq, "%9llu ", - data->hist[cpu].max_irq); - - if (!params->no_thread) - trace_seq_printf(trace->seq, "%9llu ", - data->hist[cpu].max_thread); - - if (params->user_hist) - trace_seq_printf(trace->seq, "%9llu ", - data->hist[cpu].max_user); + if (!params->no_irq) { + if (data->hist[cpu].irq_count) + trace_seq_printf(trace->seq, "%9llu ", + data->hist[cpu].max_irq); + else + trace_seq_printf(trace->seq, " - "); + } + + if (!params->no_thread) { + if (data->hist[cpu].thread_count) + trace_seq_printf(trace->seq, "%9llu ", + data->hist[cpu].max_thread); + else + trace_seq_printf(trace->seq, " - "); + } + + if (params->user_hist) { + if (data->hist[cpu].user_count) + trace_seq_printf(trace->seq, "%9llu ", + data->hist[cpu].max_user); + else + trace_seq_printf(trace->seq, " - "); + } } trace_seq_printf(trace->seq, "\n"); trace_seq_do_printf(trace->seq);