From ad334d89a695460ca1387d96bb8ab7aef0909df4 Mon Sep 17 00:00:00 2001 From: Greg Kurz Date: Mon, 24 Feb 2020 20:23:43 +0100 Subject: [PATCH] spapr: Handle pending hot plug/unplug requests at CAS If a hot plug or unplug request is pending at CAS, we currently trigger a CAS reboot, which severely increases the guest boot time. This is because SLOF doesn't handle hot plug events and we had no way to fix the FDT that gets presented to the guest. We can do better thanks to recent changes in QEMU and SLOF: - we now return a full FDT to SLOF during CAS - SLOF was fixed to correctly detect any device that was either added or removed since boot time and to update its internal DT accordingly. The right solution is to process all pending hot plug/unplug requests during CAS: convert hot plugged devices to cold plugged devices and remove the hot unplugged ones, which is exactly what spapr_drc_reset() does. Also clear all hot plug events that are currently queued since they're no longer relevant. Note that SLOF cannot currently populate hot plugged PCI bridges or PHBs at CAS. Until this limitation is lifted, SLOF will reset the machine when this scenario occurs : this will allow the FDT to be fully processed when SLOF is started again (ie. the same effect as the CAS reboot that would occur anyway without this patch). Signed-off-by: Greg Kurz Message-Id: <158257222352.4102917.8984214333937947307.stgit@bahia.lan> Signed-off-by: David Gibson --- hw/ppc/spapr_events.c | 13 +++++++++++++ hw/ppc/spapr_hcall.c | 11 +++++------ include/hw/ppc/spapr.h | 1 + 3 files changed, 19 insertions(+), 6 deletions(-) diff --git a/hw/ppc/spapr_events.c b/hw/ppc/spapr_events.c index 8b32b7eea5..2afd1844e4 100644 --- a/hw/ppc/spapr_events.c +++ b/hw/ppc/spapr_events.c @@ -983,6 +983,19 @@ void spapr_clear_pending_events(SpaprMachineState *spapr) } } +void spapr_clear_pending_hotplug_events(SpaprMachineState *spapr) +{ + SpaprEventLogEntry *entry = NULL, *next_entry; + + QTAILQ_FOREACH_SAFE(entry, &spapr->pending_events, next, next_entry) { + if (spapr_event_log_entry_type(entry) == RTAS_LOG_TYPE_HOTPLUG) { + QTAILQ_REMOVE(&spapr->pending_events, entry, next); + g_free(entry->extended_log); + g_free(entry); + } + } +} + void spapr_events_init(SpaprMachineState *spapr) { int epow_irq = SPAPR_IRQ_EPOW; diff --git a/hw/ppc/spapr_hcall.c b/hw/ppc/spapr_hcall.c index 934eb12d27..c2b3286625 100644 --- a/hw/ppc/spapr_hcall.c +++ b/hw/ppc/spapr_hcall.c @@ -1640,7 +1640,7 @@ static uint32_t cas_check_pvr(SpaprMachineState *spapr, PowerPCCPU *cpu, return best_compat; } -static bool spapr_transient_dev_before_cas(void) +static void spapr_handle_transient_dev_before_cas(SpaprMachineState *spapr) { Object *drc_container; ObjectProperty *prop; @@ -1658,10 +1658,11 @@ static bool spapr_transient_dev_before_cas(void) prop->name, NULL)); if (spapr_drc_transient(drc)) { - return true; + spapr_drc_reset(drc); } } - return false; + + spapr_clear_pending_hotplug_events(spapr); } static target_ulong h_client_architecture_support(PowerPCCPU *cpu, @@ -1834,9 +1835,7 @@ static target_ulong h_client_architecture_support(PowerPCCPU *cpu, spapr_irq_update_active_intc(spapr); - if (spapr_transient_dev_before_cas()) { - spapr->cas_reboot = true; - } + spapr_handle_transient_dev_before_cas(spapr); if (!spapr->cas_reboot) { void *fdt; diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h index 09110961a5..a4216935a1 100644 --- a/include/hw/ppc/spapr.h +++ b/include/hw/ppc/spapr.h @@ -824,6 +824,7 @@ int spapr_hpt_shift_for_ramsize(uint64_t ramsize); void spapr_reallocate_hpt(SpaprMachineState *spapr, int shift, Error **errp); void spapr_clear_pending_events(SpaprMachineState *spapr); +void spapr_clear_pending_hotplug_events(SpaprMachineState *spapr); int spapr_max_server_number(SpaprMachineState *spapr); void spapr_store_hpte(PowerPCCPU *cpu, hwaddr ptex, uint64_t pte0, uint64_t pte1); -- 2.11.4.GIT