From 3ccf3e8306156a28213adc720aba807e9a901ad5 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Mon, 27 Feb 2012 10:47:00 +0100 Subject: printk/sched: Introduce special printk_sched() for those awkward moments There's a few awkward printk()s inside of scheduler guts that people prefer to keep but really are rather deadlock prone. Fudge around it by storing the text in a per-cpu buffer and poll it using the existing printk_tick() handler. This will drop output when its more frequent than once a tick, however only the affinity thing could possible go that fast and for that just one should suffice to notify the admin he's done something silly.. Signed-off-by: Peter Zijlstra Cc: Linus Torvalds Cc: Andrew Morton Link: http://lkml.kernel.org/n/tip-wua3lmkt3dg8nfts66o6brne@git.kernel.org Signed-off-by: Ingo Molnar --- kernel/sched/core.c | 2 +- kernel/sched/rt.c | 8 +++++++- 2 files changed, 8 insertions(+), 2 deletions(-) (limited to 'kernel/sched') diff --git a/kernel/sched/core.c b/kernel/sched/core.c index b1ccce819ce..8781cec7c3e 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1284,7 +1284,7 @@ static int select_fallback_rq(int cpu, struct task_struct *p) * leave kernel. */ if (p->mm && printk_ratelimit()) { - printk(KERN_INFO "process %d (%s) no longer affine to cpu%d\n", + printk_sched("process %d (%s) no longer affine to cpu%d\n", task_pid_nr(p), p->comm, cpu); } diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 7f7e7cdcb47..b60dad72017 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -864,8 +864,14 @@ static int sched_rt_runtime_exceeded(struct rt_rq *rt_rq) * but accrue some time due to boosting. */ if (likely(rt_b->rt_runtime)) { + static bool once = false; + rt_rq->rt_throttled = 1; - printk_once(KERN_WARNING "sched: RT throttling activated\n"); + + if (!once) { + once = true; + printk_sched("sched: RT throttling activated\n"); + } } else { /* * In case we did anyway, make it go away, -- cgit v1.2.3-70-g09d2