From: Benjamin Herrenschmidt Date: Wed, 10 Jan 2018 06:10:12 +0000 (+1100) Subject: powerpc: Don't preempt_disable() in show_cpuinfo() X-Git-Tag: v4.15-rc9~17^2~3 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=349524bc0da698ec77f2057cf4a4948eb6349265;p=linux.git powerpc: Don't preempt_disable() in show_cpuinfo() This causes warnings from cpufreq mutex code. This is also rather unnecessary and ineffective. If we really want to prevent concurrent unplug, we could take the unplug read lock but I don't see this being critical. Fixes: cd77b5ce208c ("powerpc/powernv/cpufreq: Fix the frequency read by /proc/cpuinfo") Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Michael Ellerman --- diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c index 9d213542a48b..8fd3a70047f1 100644 --- a/arch/powerpc/kernel/setup-common.c +++ b/arch/powerpc/kernel/setup-common.c @@ -242,14 +242,6 @@ static int show_cpuinfo(struct seq_file *m, void *v) unsigned short maj; unsigned short min; - /* We only show online cpus: disable preempt (overzealous, I - * knew) to prevent cpu going down. */ - preempt_disable(); - if (!cpu_online(cpu_id)) { - preempt_enable(); - return 0; - } - #ifdef CONFIG_SMP pvr = per_cpu(cpu_pvr, cpu_id); #else @@ -358,9 +350,6 @@ static int show_cpuinfo(struct seq_file *m, void *v) #ifdef CONFIG_SMP seq_printf(m, "\n"); #endif - - preempt_enable(); - /* If this is the last cpu, print the summary */ if (cpumask_next(cpu_id, cpu_online_mask) >= nr_cpu_ids) show_cpuinfo_summary(m);