FAILED: patch "[PATCH] rtla/timerlat: Fix histogram report when a cpu count is 0" failed to apply to 6.1-stable tree

The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 01b05fc0e5f3aec443a9a8ffa0022cbca2fd3608
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2024061354-playtime-clumsy-d741@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..

Possible dependencies:

01b05fc0e5f3 ("rtla/timerlat: Fix histogram report when a cpu count is 0") ed774f7481fa ("rtla/timerlat_hist: Add timerlat user-space support") 2091336b9a8b ("rtla/timerlat_hist: Add auto-analysis support") 272ced2556e6 ("rtla: Add --house-keeping option")
a957cbc02531 ("rtla: Add -C cgroup support")
9fa48a2477de ("rtla/timerlat: Add auto-analysis only option") 1f428356c38d ("rtla: Add hwnoise tool")
ce6cc6f70cad ("Documentation/rtla: Add timerlat-top auto-analysis options") 5def33df84d2 ("rtla/timerlat: Add auto-analysis support to timerlat top")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 01b05fc0e5f3aec443a9a8ffa0022cbca2fd3608 Mon Sep 17 00:00:00 2001
From: John Kacur <[email protected]>
Date: Fri, 10 May 2024 15:03:18 -0400
Subject: [PATCH] rtla/timerlat: Fix histogram report when a cpu count is 0

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.

index d4bab86ca1b9..fbe2c6549bf9 100644
@@ -327,17 +327,29 @@ timerlat_print_summary(struct timerlat_hist_params *params,
 		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_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)
-			trace_seq_printf(trace->seq, "%9llu ",
-					data->hist[cpu].min_thread);
+		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)
-			trace_seq_printf(trace->seq, "%9llu ",
-					data->hist[cpu].min_user);
+		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");
 

@@ -387,17 +399,29 @@ timerlat_print_summary(struct timerlat_hist_params *params,
 		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_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)
-			trace_seq_printf(trace->seq, "%9llu ",
-					data->hist[cpu].max_thread);
+		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)
-			trace_seq_printf(trace->seq, "%9llu ",
-					data->hist[cpu].max_user);
+		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);