vtime: Warn if irqs aren't disabled on system time accounting APIs (1b2852b1) · Commits · 戴 / test

System time accounting APIs such as vtime_account_system() and vtime_account_idle() need to be irqsafe. Current callers include irq entry, exit and kvm, all of which have been checked against that requirement. Now it's better to grow that with an automatic check in case we have further callers or we missed something. Suggested-by:

Steven Rostedt <rostedt@goodmis.org> Signed-off-by:

Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com>

arch/ia64/kernel/time.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -119,6 +119,8 @@ static cputime_t vtime_delta(struct task_struct *tsk)
		cputime_t delta_stime;
		__u64 now;

		WARN_ON_ONCE(!irqs_disabled());

		now = ia64_get_itc();

		delta_stime = cycle_to_cputime(ti->ac_stime + (now - ti->ac_stamp));

arch/powerpc/kernel/time.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -297,6 +297,8 @@ static u64 vtime_delta(struct task_struct *tsk,
		u64 now, nowscaled, deltascaled;
		u64 udelta, delta, user_scaled;

		WARN_ON_ONCE(!irqs_disabled());

		now = mftb();
		nowscaled = read_spurr(now);
		get_paca()->system_time += now - get_paca()->starttime;

arch/s390/kernel/vtime.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -132,6 +132,8 @@ void vtime_account(struct task_struct *tsk)
		struct thread_info *ti = task_thread_info(tsk);
		u64 timer, system;

		WARN_ON_ONCE(!irqs_disabled());

		timer = S390_lowcore.last_update_timer;
		S390_lowcore.last_update_timer = get_vtimer();
		S390_lowcore.system_timer += timer - S390_lowcore.last_update_timer;

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