From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julia Lawall Date: Sat, 15 Jul 2017 20:59:35 +0000 Subject: Re: [PATCH 06/11] irqchip: mips-cpu: Drop unnecessary static Message-Id: List-Id: References: <1500149266-32357-1-git-send-email-Julia.Lawall@lip6.fr> <1500149266-32357-7-git-send-email-Julia.Lawall@lip6.fr> <83D70E98-A5D4-48E5-9397-25826083E2A8@gmail.com> In-Reply-To: <83D70E98-A5D4-48E5-9397-25826083E2A8@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Mark D Rustad Cc: Julia Lawall , Thomas Gleixner , keescook@chromium.org, kernel-janitors@vger.kernel.org, Jason Cooper , Marc Zyngier , linux-kernel@vger.kernel.org On Sat, 15 Jul 2017, Mark D Rustad wrote: > > > On Jul 15, 2017, at 1:07 PM, Julia Lawall wrote: > > > > Drop static on a local variable, when the variable is initialized before > > any possible use. Thus, the static has no benefit. > > I think this is in error like the other one. I believe that the irq_chip structure needs a persistent lifetime. I'm not following in this case. chip is a pointer to a structure, not a structure. Its address is not taken. irq_set_chip_and_handler that uses it below is a fnuction, so it just gets the value. julia > > > The semantic patch that fixes this problem is as follows: > > (http://coccinelle.lip6.fr/) > > > > // > > @bad exists@ > > position p; > > identifier x; > > type T; > > @@ > > static T x@p; > > ... > > x = <+...x...+> > > > > @@ > > identifier x; > > expression e; > > type T; > > position p != bad.p; > > @@ > > -static > > T x@p; > > ... when != x > > when strict > > ?x = e; > > // > > > > Signed-off-by: Julia Lawall > > > > --- > > These patches are all independent of each other. > > > > drivers/irqchip/irq-mips-cpu.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff -u -p a/drivers/irqchip/irq-mips-cpu.c b/drivers/irqchip/irq-mips-cpu.c > > --- a/drivers/irqchip/irq-mips-cpu.c > > +++ b/drivers/irqchip/irq-mips-cpu.c > > @@ -154,7 +154,7 @@ asmlinkage void __weak plat_irq_dispatch > > static int mips_cpu_intc_map(struct irq_domain *d, unsigned int irq, > > irq_hw_number_t hw) > > { > > - static struct irq_chip *chip; > > + struct irq_chip *chip; > > > > if (hw < 2 && cpu_has_mipsmt) { > > /* Software interrupts are used for MT/CMT IPI */ > > > > -- > Mark Rustad, MRustad@gmail.com > >