linux-kernel - [PATCH] timekeeping: Convert jiffies_seq to seqcount_raw_spinlock

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20201021190749.19363-1-dave@stgolabs.net>
Date:   Wed, 21 Oct 2020 12:07:49 -0700
From:   Davidlohr Bueso <dave@...olabs.net>
To:     peterz@...radead.org
Cc:     tglx@...utronix.de, mingo@...nel.org, a.darwish@...utronix.de,
        dave@...olabs.net, linux-kernel@...r.kernel.org,
        Davidlohr Bueso <dbueso@...e.de>
Subject: [PATCH] timekeeping: Convert jiffies_seq to seqcount_raw_spinlock_t

Use the new api and associate the seqcounter to the jiffies_lock enabling
lockdep support - although for this particular case the write-side locking
and non-preemptibility are quite obvious.

Signed-off-by: Davidlohr Bueso <dbueso@...e.de>
---
 kernel/time/jiffies.c     | 3 ++-
 kernel/time/timekeeping.h | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/kernel/time/jiffies.c b/kernel/time/jiffies.c
index eddcf4970444..a5cffe2a1770 100644
--- a/kernel/time/jiffies.c
+++ b/kernel/time/jiffies.c
@@ -59,7 +59,8 @@ static struct clocksource clocksource_jiffies = {
 };
 
 __cacheline_aligned_in_smp DEFINE_RAW_SPINLOCK(jiffies_lock);
-__cacheline_aligned_in_smp seqcount_t jiffies_seq;
+__cacheline_aligned_in_smp seqcount_raw_spinlock_t jiffies_seq =
+	SEQCNT_RAW_SPINLOCK_ZERO(jiffies_seq, &jiffies_lock);
 
 #if (BITS_PER_LONG < 64)
 u64 get_jiffies_64(void)
diff --git a/kernel/time/timekeeping.h b/kernel/time/timekeeping.h
index 099737f6f10c..6c2cbd9ef999 100644
--- a/kernel/time/timekeeping.h
+++ b/kernel/time/timekeeping.h
@@ -26,7 +26,7 @@ extern void do_timer(unsigned long ticks);
 extern void update_wall_time(void);
 
 extern raw_spinlock_t jiffies_lock;
-extern seqcount_t jiffies_seq;
+extern seqcount_raw_spinlock_t jiffies_seq;
 
 #define CS_NAME_LEN	32
 
-- 
2.26.2