On 12/17/2024 9:33 AM, Julia Lawall wrote:

On Tue, 17 Dec 2024, Alexander Gordeev wrote:

quoted

On Tue, Dec 10, 2024 at 10:02:33PM +0000, Easwar Hariharan wrote:

Hi Easwar,

quoted

This script finds and suggests conversions of timeout patterns that
result in seconds-denominated timeouts to use the new secs_to_jiffies()
API in include/linux/jiffies.h for better readability.

Suggested-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Easwar Hariharan <redacted>
---
 scripts/coccinelle/misc/secs_to_jiffies.cocci | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/scripts/coccinelle/misc/secs_to_jiffies.cocci b/scripts/coccinelle/misc/secs_to_jiffies.cocci
new file mode 100644
index 0000000000000000000000000000000000000000..8bbb2884ea5db939c63fd4513cf5ca8c977aa8cb
--- /dev/null
+++ b/scripts/coccinelle/misc/secs_to_jiffies.cocci

@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0-only
+///
+/// Find usages of:
+/// - msecs_to_jiffies(value*1000)
+/// - msecs_to_jiffies(value*MSEC_PER_SEC)
+///
+// Confidence: High
+// Copyright: (C) 2024 Easwar Hariharan, Microsoft
+// Keywords: secs, seconds, jiffies
+//
+
+virtual patch
+
+@depends on patch@ constant C; @@
+
+- msecs_to_jiffies(C * 1000)
++ secs_to_jiffies(C)
+
+@depends on patch@ constant C; @@
+
+- msecs_to_jiffies(C * MSEC_PER_SEC)
++ secs_to_jiffies(C)

If you used this script only, then it did not seem to recognize line arch/s390/mm/cmm.c:207

	mod_timer(&cmm_timer, jiffies + msecs_to_jiffies(cmm_timeout_seconds * MSEC_PER_SEC));

There is the requirement that C is a constant, and cmm_timeout_seconds is
not considered to be a constant, ie it is not all capital letters.
Indeed, it doesn't seem to be a constant at all.  I don't know if the
requirement of being a comstant is really necessary.

julia

quoted

Thanks!

As the cover letter says, this is part 1. I intend to do further parts
that address the cases where the multiplicand is an expression, as well
as the cases where the timeout provided to msecs_to_jiffies() is
denominated in seconds (i.e. ends in 000)

Thanks,
Easwar