diff options
| author | Catalin Marinas <catalin.marinas@arm.com> | 2007-02-15 19:05:29 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2007-02-16 13:06:56 +0000 |
| commit | 0e0ba76926c37f11f38670db0cb33728f502551e (patch) | |
| tree | ef6c4b005b64fe9c42a2a9cd903442b1e252797d /arch | |
| parent | 7770bddb27ea84519486d8bb5d35d36d580c451b (diff) | |
[ARM] 4201/1: SMP barriers pair needed for the secondary boot process
In some situations, the pen_release store in platform_secondary_init()
may stay forever in the write buffer while the CPU is waiting on the
boot_lock to be released in boot_secondary(). The primary CPU could
never see the pen_release update without the barriers.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm/mach-realview/platsmp.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/arm/mach-realview/platsmp.c b/arch/arm/mach-realview/platsmp.c index 709a9b1ac634..fce3596f9950 100644 --- a/arch/arm/mach-realview/platsmp.c +++ b/arch/arm/mach-realview/platsmp.c @@ -59,6 +59,7 @@ void __cpuinit platform_secondary_init(unsigned int cpu) * pen, then head off into the C entry point */ pen_release = -1; + smp_wmb(); /* * Synchronise with the boot thread. @@ -102,6 +103,7 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle) timeout = jiffies + (1 * HZ); while (time_before(jiffies, timeout)) { + smp_rmb(); if (pen_release == -1) break; |