Messages in this thread | | | Date | Mon, 23 Sep 2019 10:47:18 +0200 | From | Peter Zijlstra <> | Subject | Re: [RFC patch 10/15] x86/entry: Move irq tracing to C code |
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On Thu, Sep 19, 2019 at 05:03:24PM +0200, Thomas Gleixner wrote: > To prepare for converting the exit to usermode code to the generic version, > move the irqflags tracing into C code. > > Signed-off-by: Thomas Gleixner <tglx@linutronix.de> > --- > arch/x86/entry/common.c | 10 ++++++++++ > arch/x86/entry/entry_32.S | 11 +---------- > arch/x86/entry/entry_64.S | 10 ++-------- > arch/x86/entry/entry_64_compat.S | 21 --------------------- > 4 files changed, 13 insertions(+), 39 deletions(-) > > --- a/arch/x86/entry/common.c > +++ b/arch/x86/entry/common.c > @@ -102,6 +102,8 @@ static void exit_to_usermode_loop(struct > struct thread_info *ti = current_thread_info(); > u32 cached_flags; > > + trace_hardirqs_off();
Bah.. so this gets called from:
- C code, with IRQs disabled - entry_64.S:error_exit - entry_32.S:resume_userspace
The first obviously doesn't need this annotation, but this patch doesn't remove the TRACE_IRQS_OFF from entry_64.S and only the 32bit case is changed.
Is that entry_64.S case an oversight, or do we need an extensive comment on this one?
> addr_limit_user_check(); > > lockdep_assert_irqs_disabled(); > @@ -137,6 +139,8 @@ static void exit_to_usermode_loop(struct > user_enter_irqoff(); > > mds_user_clear_cpu_buffers(); > +
/* Return to userspace (IRET) will re-enable interrupts */ > + trace_hardirqs_on(); > }
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