diff options
| author | Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com> | 2010-03-01 02:58:16 +0000 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2010-03-09 11:57:10 +1100 |
| commit | 0212f2602a38e740d5a96aba4cebfc2ebc993ecf (patch) | |
| tree | c65166065be1d195ca603b7d71f8ed4f5d32e223 | |
| parent | 8dbce53cc249a76e9450708d291fce5a7e29c6a1 (diff) | |
powerpc: Move checks in pseries_mach_cpu_die()
Rearrange condition checks for better code readability and
prevention of possible race conditions when
preferred_offline_state can potentially change during the
execution of pseries_mach_cpu_die(). The patch will make
pseries_mach_cpu_die() put cpu in one of the consistent states
and not hit the run over BUG()
Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| -rw-r--r-- | arch/powerpc/platforms/pseries/hotplug-cpu.c | 30 |
1 files changed, 15 insertions, 15 deletions
diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c index 349e0af9389..fefb7f84800 100644 --- a/arch/powerpc/platforms/pseries/hotplug-cpu.c +++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c @@ -140,25 +140,25 @@ static void pseries_mach_cpu_die(void) if (!get_lppaca()->shared_proc) get_lppaca()->donate_dedicated_cpu = 0; get_lppaca()->idle = 0; - } - if (get_preferred_offline_state(cpu) == CPU_STATE_ONLINE) { - unregister_slb_shadow(hwcpu, __pa(get_slb_shadow())); + if (get_preferred_offline_state(cpu) == CPU_STATE_ONLINE) { + unregister_slb_shadow(hwcpu, __pa(get_slb_shadow())); - /* - * Call to start_secondary_resume() will not return. - * Kernel stack will be reset and start_secondary() - * will be called to continue the online operation. - */ - start_secondary_resume(); + /* + * Call to start_secondary_resume() will not return. + * Kernel stack will be reset and start_secondary() + * will be called to continue the online operation. + */ + start_secondary_resume(); + } + } - } else if (get_preferred_offline_state(cpu) == CPU_STATE_OFFLINE) { + /* Requested state is CPU_STATE_OFFLINE at this point */ + WARN_ON(get_preferred_offline_state(cpu) != CPU_STATE_OFFLINE); - set_cpu_current_state(cpu, CPU_STATE_OFFLINE); - unregister_slb_shadow(hard_smp_processor_id(), - __pa(get_slb_shadow())); - rtas_stop_self(); - } + set_cpu_current_state(cpu, CPU_STATE_OFFLINE); + unregister_slb_shadow(hwcpu, __pa(get_slb_shadow())); + rtas_stop_self(); /* Should never get here... */ BUG(); |