[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <1376189294-32022-22-git-send-email-yinghai@kernel.org>
Date: Sat, 10 Aug 2013 19:48:07 -0700
From: Yinghai Lu <yinghai@...nel.org>
To: Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar <mingo@...e.hu>,
"H. Peter Anvin" <hpa@...or.com>, Tony Luck <tony.luck@...el.com>,
Bjorn Helgaas <bhelgaas@...gle.com>,
"Rafael J. Wysocki" <rjw@...k.pl>
Cc: linux-pci@...r.kernel.org, linux-kernel@...r.kernel.org,
linux-acpi@...r.kernel.org, Yinghai Lu <yinghai@...nel.org>,
Paul Gortmaker <paul.gortmaker@...driver.com>,
Joerg Roedel <joro@...tes.org>,
Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>,
Sebastian Andrzej Siewior <sebastian@...akpoint.cc>
Subject: [PATCH v4 21/28] x86, irq: Make mp_register_ioapic handle hot-added ioapic
It needs to reserve irq range in allocated_irqs bitmaps
and irq_base will be used to get right irq for ioapic/pin or gsi.
also need to use lock to protect ioapics_mask to avoid racing.
Signed-off-by: Yinghai Lu <yinghai@...nel.org>
Cc: Paul Gortmaker <paul.gortmaker@...driver.com>
Cc: Joerg Roedel <joro@...tes.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
Cc: Sebastian Andrzej Siewior <sebastian@...akpoint.cc>
---
arch/x86/include/asm/mpspec.h | 1 +
arch/x86/kernel/apic/io_apic.c | 68 ++++++++++++++++++++++++++++++++----------
2 files changed, 54 insertions(+), 15 deletions(-)
diff --git a/arch/x86/include/asm/mpspec.h b/arch/x86/include/asm/mpspec.h
index 626cf70..13cf60c 100644
--- a/arch/x86/include/asm/mpspec.h
+++ b/arch/x86/include/asm/mpspec.h
@@ -96,6 +96,7 @@ static inline void early_reserve_e820_mpc_new(void) { }
void generic_processor_info(int apicid, int version);
#ifdef CONFIG_ACPI
+int __mp_register_ioapic(int id, u32 address, u32 gsi_base, bool hot);
extern void mp_register_ioapic(int id, u32 address, u32 gsi_base);
extern void mp_override_legacy_irq(u8 bus_irq, u8 polarity, u8 trigger,
u32 gsi);
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 60c6706..1616a35 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -94,6 +94,16 @@ static struct ioapic {
} ioapics[MAX_IO_APICS];
DECLARE_BITMAP(ioapics_mask, MAX_IO_APICS);
+static DEFINE_MUTEX(ioapics_mask_lock);
+
+static void lock_ioapics(void)
+{
+ mutex_lock(&ioapics_mask_lock);
+}
+static void unlock_ioapics(void)
+{
+ mutex_unlock(&ioapics_mask_lock);
+}
#define mpc_ioapic_ver(ioapic_idx) ioapics[ioapic_idx].mp_config.apicver
@@ -3885,25 +3895,28 @@ static __init int bad_ioapic_register(int idx)
return 0;
}
-void __init mp_register_ioapic(int id, u32 address, u32 gsi_base)
+int __mp_register_ioapic(int id, u32 address, u32 gsi_base, bool hotadd)
{
int idx;
int entries;
struct mp_ioapic_gsi *gsi_cfg;
+ int ret = -EINVAL;
if (bad_ioapic(address))
- return;
+ return ret;
+
+ lock_ioapics();
/* already registered ? */
idx = __mp_find_ioapic(gsi_base);
if (idx >= 0)
- return;
+ goto out;
idx = find_first_zero_bit(ioapics_mask, MAX_IO_APICS);
if (idx >= MAX_IO_APICS) {
pr_warn("WARNING: Max # of I/O APICs (%d) exceeded, skipping\n",
MAX_IO_APICS);
- return;
+ goto out;
}
ioapics[idx].mp_config.type = MP_IOAPIC;
@@ -3912,10 +3925,8 @@ void __init mp_register_ioapic(int id, u32 address, u32 gsi_base)
set_fixmap_nocache(FIX_IO_APIC_BASE_0 + idx, address);
- if (bad_ioapic_register(idx)) {
- clear_fixmap(FIX_IO_APIC_BASE_0 + idx);
- return;
- }
+ if (bad_ioapic_register(idx))
+ goto clear_out;
ioapics[idx].mp_config.apicid = io_apic_unique_id(id);
ioapics[idx].mp_config.apicver = io_apic_get_version(idx);
@@ -3926,11 +3937,8 @@ void __init mp_register_ioapic(int id, u32 address, u32 gsi_base)
*/
entries = io_apic_get_redir_entries(idx);
- if (!entries || entries > MP_MAX_IOAPIC_PIN) {
- clear_fixmap(FIX_IO_APIC_BASE_0 + idx);
- memset(&ioapics[idx], 0, sizeof(struct ioapic));
- return;
- }
+ if (!entries || entries > MP_MAX_IOAPIC_PIN)
+ goto clear_out;
gsi_cfg = mp_ioapic_gsi_routing(idx);
gsi_cfg->gsi_base = gsi_base;
@@ -3941,8 +3949,21 @@ void __init mp_register_ioapic(int id, u32 address, u32 gsi_base)
*/
ioapics[idx].nr_registers = entries;
- if (gsi_cfg->gsi_end >= gsi_top)
- gsi_top = gsi_cfg->gsi_end + 1;
+ if (!hotadd) {
+ /*
+ * irqs will be reserved in arch_early_irq_init()
+ * don't need to update gsi_top for hot add case
+ */
+ if (gsi_cfg->gsi_end >= gsi_top)
+ gsi_top = gsi_cfg->gsi_end + 1;
+ } else {
+ int irq = reserve_ioapic_gsi_irq_base(idx);
+
+ if (irq < 0)
+ goto clear_out;
+
+ alloc_ioapic_saved_registers(idx);
+ }
pr_info("IOAPIC[%d]: apic_id %d, version %d, address 0x%x, GSI %d-%d\n",
idx, mpc_ioapic_id(idx),
@@ -3951,6 +3972,23 @@ void __init mp_register_ioapic(int id, u32 address, u32 gsi_base)
set_bit(idx, ioapics_mask);
nr_ioapics = bitmap_weight(ioapics_mask, MAX_IO_APICS);
+
+ unlock_ioapics();
+
+ return 0;
+
+clear_out:
+ clear_fixmap(FIX_IO_APIC_BASE_0 + idx);
+ memset(&ioapics[idx], 0, sizeof(struct ioapic));
+out:
+ unlock_ioapics();
+
+ return ret;
+}
+
+void mp_register_ioapic(int id, u32 address, u32 gsi_base)
+{
+ __mp_register_ioapic(id, address, gsi_base, false);
}
/* Enable IOAPIC early just for system timer */
--
1.8.1.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists