The patch titled
Subject: sched: avoid using ilog2() in sched.h
has been added to the -mm mm-nonmm-unstable branch. Its filename is
sched-avoid-using-ilog2-in-schedh.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/sched-avoid-using-ilog2-in-schedh.patch
This patch will later appear in the mm-nonmm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Yury Norov <yury.norov@xxxxxxxxx>
Subject: sched: avoid using ilog2() in sched.h
Date: Mon, 27 May 2024 17:56:44 -0700
<linux/sched.h> indirectly via cpumask.h path includes the ilog2.h header
to calculate ilog2(TASK_REPORT_MAX). The following patches drops sched.h
dependency on cpumask.h, and to have a successful build, the header has to
be included explicitly.
sched.h is a frequently included header, and it's better to keep the
dependency list as small as possible. So, instead of including ilog2.h
for a single BUILD_BUG_ON() check, the same check may be implemented by
taking exponent of the other part of equation.
Link: https://lkml.kernel.org/r/20240528005648.182376-3-yury.norov@xxxxxxxxx
Signed-off-by: Yury Norov <yury.norov@xxxxxxxxx>
Cc: Amit Daniel Kachhap <amit.kachhap@xxxxxxxxx>
Cc: Anna-Maria Behnsen <anna-maria@xxxxxxxxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
Cc: Dennis Zhou <dennis@xxxxxxxxxx>
Cc: Frederic Weisbecker <frederic@xxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Juri Lelli <juri.lelli@xxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Cc: Paul E. McKenney <paulmck@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Rafael J. Wysocki <rafael@xxxxxxxxxx>
Cc: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Cc: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
Cc: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Cc: Yury Norov <yury.norov@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/sched.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/include/linux/sched.h~sched-avoid-using-ilog2-in-schedh
+++ a/include/linux/sched.h
@@ -1604,7 +1604,7 @@ static inline char task_index_to_char(un
{
static const char state_char[] = "RSDTtXZPI";
- BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1);
+ BUILD_BUG_ON(TASK_REPORT_MAX * 2 != 1 << (sizeof(state_char) - 1));
return state_char[state];
}
_
Patches currently in -mm which might be from yury.norov@xxxxxxxxx are
gcc-disable-warray-bounds-for-gcc-9.patch
maintainers-add-linux-nodemask_typesh-to-bitmap-api.patch
sched-avoid-using-ilog2-in-schedh.patch
sched-drop-schedh-dependency-on-cpumask.patch
cpumask-cleanup-core-headers-inclusion.patch
cpumask-make-core-headers-including-cpumask_typesh-where-possible.patch
