[linux-yocto] [PATCH 04/10] irqchip/gic-v3-its: Move pending table allocation to init time
Paul Gortmaker
paul.gortmaker at windriver.com
Mon Oct 1 09:33:04 PDT 2018
From: Marc Zyngier <marc.zyngier at arm.com>
commit 4a0819bb25d12d39c0390636122eefba232596c1 from linux-rt-devel.
Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
[bigeasy: backport commit effe377d415 ("irqchip/gic-v3-its: Move pending
table allocation to init time")]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy at linutronix.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker at windriver.com>
---
drivers/irqchip/irq-gic-v3-its.c | 94 +++++++++++++++++++-------------------
include/linux/irqchip/arm-gic-v3.h | 1 +
2 files changed, 49 insertions(+), 46 deletions(-)
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 4bca2439ee7d..907e5c5169e9 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1556,7 +1556,7 @@ 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;
@@ -1854,17 +1854,15 @@ static int its_alloc_collections(struct its_node *its)
return 0;
}
-static struct page *its_allocate_pending_table(unsigned int cpu)
+static struct page *its_allocate_pending_table(gfp_t gfp_flags)
{
struct page *pend_page;
- unsigned int order;
/*
* The pending pages have to be at least 64kB aligned,
* hence the 'max(LPI_PENDBASE_SZ, SZ_64K)' below.
*/
- order = get_order(max_t(u32, LPI_PENDBASE_SZ, SZ_64K));
- pend_page = alloc_pages_node(cpu_to_node(cpu), GFP_KERNEL | __GFP_ZERO,
- order);
+ pend_page = alloc_pages(gfp_flags | __GFP_ZERO,
+ get_order(max_t(u32, LPI_PENDBASE_SZ, SZ_64K)));
if (!pend_page)
return NULL;
@@ -1880,25 +1878,31 @@ static void its_free_pending_table(struct page *pt)
get_order(max_t(u32, LPI_PENDBASE_SZ, SZ_64K)));
}
-static int its_alloc_pend_page(unsigned int cpu)
+static int __init allocate_lpi_tables(void)
{
- struct page *pend_page;
- phys_addr_t paddr;
+ int err, cpu;
- pend_page = gic_data_rdist_cpu(cpu)->pend_page;
- if (pend_page)
- return 0;
+ err = its_alloc_lpi_prop_table();
+ if (err)
+ return err;
- pend_page = its_allocate_pending_table(cpu);
- if (!pend_page) {
- pr_err("Failed to allocate PENDBASE for CPU%d\n",
- smp_processor_id());
- return -ENOMEM;
+ /*
+ * 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", cpu);
+ return -ENOMEM;
+ }
+
+ gic_data_rdist_cpu(cpu)->pend_page = pend_page;
}
- paddr = page_to_phys(pend_page);
- pr_info("CPU%d: using LPI pending table @%pa\n", cpu, &paddr);
- gic_data_rdist_cpu(cpu)->pend_page = pend_page;
return 0;
}
@@ -1906,13 +1910,15 @@ 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 we didn't allocate the pending table yet, do it now */
- pend_page = gic_data_rdist()->pend_page;
- if (!pend_page)
+ 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 |
@@ -1964,6 +1970,10 @@ 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)
@@ -2744,7 +2754,7 @@ static int its_vpe_init(struct its_vpe *vpe)
return vpe_id;
/* Allocate VPT */
- vpt_page = its_allocate_pending_table(raw_smp_processor_id());
+ vpt_page = its_allocate_pending_table(GFP_KERNEL);
if (!vpt_page) {
its_vpe_id_free(vpe_id);
return -ENOMEM;
@@ -3439,16 +3449,6 @@ 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;
@@ -3458,7 +3458,18 @@ 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);
@@ -3714,18 +3725,9 @@ int __init its_init(struct fwnode_handle *handle, struct rdists *rdists,
}
gic_rdists = rdists;
- err = its_alloc_lpi_tables();
- if (err)
- return err;
- err = cpuhp_setup_state(CPUHP_BP_PREPARE_DYN, "irqchip/arm/gicv3:prepare",
- its_alloc_pend_page, NULL);
- if (err < 0) {
- pr_warn("ITS: Can't register CPU-hoplug callback.\n");
- return err;
- }
- err = its_alloc_pend_page(smp_processor_id());
- if (err < 0)
+ err = allocate_lpi_tables();
+ if (err)
return err;
list_for_each_entry(its, &its_nodes, entry)
diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h
index cbb872c1b607..f4bf3bd5f3db 100644
--- a/include/linux/irqchip/arm-gic-v3.h
+++ b/include/linux/irqchip/arm-gic-v3.h
@@ -574,6 +574,7 @@ struct rdists {
void __iomem *rd_base;
struct page *pend_page;
phys_addr_t phys_base;
+ bool lpi_enabled;
} __percpu *rdist;
struct page *prop_page;
int id_bits;
--
2.15.0
More information about the linux-yocto
mailing list