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Date:   Fri, 29 Oct 2021 11:33:28 -0700
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Subject: [PATCH 2/4] tracing/histogram: Update division by 0 documentation
From:   Kalesh Singh <kaleshsingh@google.com>
Cc:     surenb@google.com, hridya@google.com, namhyung@kernel.org,
        kernel-team@android.com, rostedt@goodmis.org, mhiramat@kernel.org,
        Kalesh Singh <kaleshsingh@google.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Ingo Molnar <mingo@redhat.com>, Shuah Khan <shuah@kernel.org>,
        Tom Zanussi <zanussi@kernel.org>, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org
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If the divisor is a constant and zero, the undeifned case can be
detected and an error returned instead of -1.

Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
---
 Documentation/trace/histogram.rst | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Documentation/trace/histogram.rst b/Documentation/trace/histogram.rst
index 66ec972dfb78..859fd1b76c63 100644
--- a/Documentation/trace/histogram.rst
+++ b/Documentation/trace/histogram.rst
@@ -1766,7 +1766,8 @@ using the same key and variable from yet another event::
 Expressions support the use of addition, subtraction, multiplication and
 division operators (+-\*/).
 
-Note that division by zero always returns -1.
+Note if division by zero cannot be detected at parse time (i.e. the
+divisor is not a constant), the result will be -1.
 
 Numeric constants can also be used directly in an expression::
 
-- 
2.33.1.1089.g2158813163f-goog