linux-kernel - Re: [PATCH v4 4/4] rcu: Add RCU stall diagnosis information

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

Date:   Fri, 4 Nov 2022 11:12:02 +0800
From:   "Leizhen (ThunderTown)" <thunder.leizhen@...wei.com>
To:     "Paul E . McKenney" <paulmck@...nel.org>,
        Frederic Weisbecker <frederic@...nel.org>,
        Neeraj Upadhyay <quic_neeraju@...cinc.com>,
        "Josh Triplett" <josh@...htriplett.org>,
        Steven Rostedt <rostedt@...dmis.org>,
        Mathieu Desnoyers <mathieu.desnoyers@...icios.com>,
        Lai Jiangshan <jiangshanlai@...il.com>,
        Joel Fernandes <joel@...lfernandes.org>, <rcu@...r.kernel.org>,
        <linux-kernel@...r.kernel.org>
CC:     Robert Elliott <elliott@....com>
Subject: Re: [PATCH v4 4/4] rcu: Add RCU stall diagnosis information



On 2022/11/4 10:12, Zhen Lei wrote:
> diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
> index d4a97e40ea9c3e2..44d49819a31f050 100644
> --- a/kernel/rcu/tree.h
> +++ b/kernel/rcu/tree.h
> @@ -158,6 +158,22 @@ union rcu_noqs {
>  	u16 s; /* Set of bits, aggregate OR here. */
>  };
>  
> +/*
> + * Record the snapshot of the core stats at 1/2 rcu stall timeout. The member
> + * gp_seq is used to ensure that all members are updated only once during the
> + * second half period. The snapshot is taken only if this gp_seq is not equal
> + * to rdp->gp_seq.
> + */
> +struct rcu_snap_record {
> +	unsigned long	gp_seq;		/* Track rdp->gp_seq counter */
> +	u64		cputime_irq;	/* Accumulated cputime of hard irqs */
> +	u64		cputime_softirq;/* Accumulated cputime of soft irqs */
> +	u64		cputime_system; /* Accumulated cputime of kernel tasks */
> +	unsigned long	nr_hardirqs;	/* Accumulated number of hard irqs */
> +	unsigned int	nr_softirqs;	/* Accumulated number of soft irqs */
> +	unsigned long long nr_csw;	/* Accumulated number of task switches */
> +};
> +
>  /* Per-CPU data for read-copy update. */
>  struct rcu_data {
>  	/* 1) quiescent-state and grace-period handling : */
> @@ -262,6 +278,7 @@ struct rcu_data {
>  	short rcu_onl_gp_flags;		/* ->gp_flags at last online. */
>  	unsigned long last_fqs_resched;	/* Time of last rcu_resched(). */
>  	unsigned long last_sched_clock;	/* Jiffies of last rcu_sched_clock_irq(). */
> +	struct rcu_snap_record snap_record; /* Snapshot of core stats at 1/2 rcu stall timeout */
>  
>  	int cpu;
>  };

Sorry, I forgot to update linux-rcu.git. There is a conflict here.

----------------
 	int cpu;
  };
------------should be--------
 	long lazy_len;			/* Length of buffered lazy callbacks. */
 	int cpu;
----------------

-- 
Regards,
  Zhen Lei