From: Marc Zyngier Date: Fri, 27 Jul 2018 13:38:54 +0100 Subject: [PATCH 008/351] irqchip/gic-v3-its: Move pending table allocation to init time Origin: https://git.kernel.org/cgit/linux/kernel/git/rt/linux-stable-rt.git/commit?id=d9fb57db9ae54bc1252eb9cb8eb620889742c94e Signed-off-by: Marc Zyngier Signed-off-by: Sebastian Andrzej Siewior --- drivers/irqchip/irq-gic-v3-its.c | 80 +++++++++++++++++++----------- include/linux/irqchip/arm-gic-v3.h | 1 + 2 files changed, 53 insertions(+), 28 deletions(-) diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index 86334aef4bd0..f51970b6b51a 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -178,6 +178,7 @@ static DEFINE_RAW_SPINLOCK(vmovp_lock); static DEFINE_IDA(its_vpeid_ida); #define gic_data_rdist() (raw_cpu_ptr(gic_rdists->rdist)) +#define gic_data_rdist_cpu(cpu) (per_cpu_ptr(gic_rdists->rdist, cpu)) #define gic_data_rdist_rd_base() (gic_data_rdist()->rd_base) #define gic_data_rdist_vlpi_base() (gic_data_rdist_rd_base() + SZ_128K) @@ -1658,7 +1659,7 @@ static void its_free_prop_table(struct page *prop_page) get_order(LPI_PROPBASE_SZ)); } -static int __init its_alloc_lpi_tables(void) +static int __init its_alloc_lpi_prop_table(void) { phys_addr_t paddr; @@ -2006,30 +2007,47 @@ static u64 its_clear_vpend_valid(void __iomem *vlpi_base) return val; } -static void its_cpu_init_lpis(void) +static int __init allocate_lpi_tables(void) { - void __iomem *rbase = gic_data_rdist_rd_base(); - struct page *pend_page; - u64 val, tmp; + int err, cpu; - /* If we didn't allocate the pending table yet, do it now */ - pend_page = gic_data_rdist()->pend_page; - if (!pend_page) { - phys_addr_t paddr; + err = its_alloc_lpi_prop_table(); + if (err) + return err; + + /* + * We allocate all the pending tables anyway, as we may have a + * mix of RDs that have had LPIs enabled, and some that + * don't. We'll free the unused ones as each CPU comes online. + */ + for_each_possible_cpu(cpu) { + struct page *pend_page; pend_page = its_allocate_pending_table(GFP_NOWAIT); if (!pend_page) { - pr_err("Failed to allocate PENDBASE for CPU%d\n", - smp_processor_id()); - return; + pr_err("Failed to allocate PENDBASE for CPU%d\n", cpu); + return -ENOMEM; } - paddr = page_to_phys(pend_page); - pr_info("CPU%d: using LPI pending table @%pa\n", - smp_processor_id(), &paddr); - gic_data_rdist()->pend_page = pend_page; + gic_data_rdist_cpu(cpu)->pend_page = pend_page; } + return 0; +} + +static void its_cpu_init_lpis(void) +{ + void __iomem *rbase = gic_data_rdist_rd_base(); + struct page *pend_page; + phys_addr_t paddr; + u64 val, tmp; + + if (gic_data_rdist()->lpi_enabled) + return; + + pend_page = gic_data_rdist()->pend_page; + paddr = page_to_phys(pend_page); + /* set PROPBASE */ val = (page_to_phys(gic_rdists->prop_page) | GICR_PROPBASER_InnerShareable | @@ -2105,6 +2123,10 @@ static void its_cpu_init_lpis(void) /* Make sure the GIC has seen the above */ dsb(sy); + gic_data_rdist()->lpi_enabled = true; + pr_info("GICv3: CPU%d: using LPI pending table @%pa\n", + smp_processor_id(), + &paddr); } static void its_cpu_init_collection(struct its_node *its) @@ -3584,16 +3606,6 @@ static int redist_disable_lpis(void) u64 timeout = USEC_PER_SEC; u64 val; - /* - * If coming via a CPU hotplug event, we don't need to disable - * LPIs before trying to re-enable them. They are already - * configured and all is well in the world. Detect this case - * by checking the allocation of the pending table for the - * current CPU. - */ - if (gic_data_rdist()->pend_page) - return 0; - if (!gic_rdists_supports_plpis()) { pr_info("CPU%d: LPIs not supported\n", smp_processor_id()); return -ENXIO; @@ -3603,7 +3615,18 @@ static int redist_disable_lpis(void) if (!(val & GICR_CTLR_ENABLE_LPIS)) return 0; - pr_warn("CPU%d: Booted with LPIs enabled, memory probably corrupted\n", + /* + * If coming via a CPU hotplug event, we don't need to disable + * LPIs before trying to re-enable them. They are already + * configured and all is well in the world. + */ + if (gic_data_rdist()->lpi_enabled) + return 0; + + /* + * From that point on, we only try to do some damage control. + */ + pr_warn("GICv3: CPU%d: Booted with LPIs enabled, memory probably corrupted\n", smp_processor_id()); add_taint(TAINT_CRAP, LOCKDEP_STILL_OK); @@ -3859,7 +3882,8 @@ int __init its_init(struct fwnode_handle *handle, struct rdists *rdists, } gic_rdists = rdists; - err = its_alloc_lpi_tables(); + + err = allocate_lpi_tables(); if (err) return err; diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h index 1d21e98d6854..fdddead7e307 100644 --- a/include/linux/irqchip/arm-gic-v3.h +++ b/include/linux/irqchip/arm-gic-v3.h @@ -585,6 +585,7 @@ struct rdists { void __iomem *rd_base; struct page *pend_page; phys_addr_t phys_base; + bool lpi_enabled; } __percpu *rdist; struct page *prop_page; u64 flags;