lkml.org 
[lkml]   [2017]   [Jun]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[tip:x86/platform] x86/PCI: Select CONFIG_PCI_LOCKLESS_CONFIG
Commit-ID:  df65c1bcd9b7b639177a5a15da1b8dc3bee4f5fa
Gitweb: http://git.kernel.org/tip/df65c1bcd9b7b639177a5a15da1b8dc3bee4f5fa
Author: Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Thu, 16 Mar 2017 22:50:07 +0100
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitDate: Wed, 28 Jun 2017 22:32:56 +0200

x86/PCI: Select CONFIG_PCI_LOCKLESS_CONFIG

All x86 PCI configuration space accessors have either their own
serialization or can operate completely lockless (ECAM).

Disable the global lock in the generic PCI configuration space accessors.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Bjorn Helgaas <helgaas@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: linux-pci@vger.kernel.org
Link: http://lkml.kernel.org/r/20170316215057.295079391@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

---
arch/x86/Kconfig | 1 +
arch/x86/pci/common.c | 4 ++--
2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 0efb4c9..0652c9f 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -166,6 +166,7 @@ config X86
select HAVE_UNSTABLE_SCHED_CLOCK
select HAVE_USER_RETURN_NOTIFIER
select IRQ_FORCED_THREADING
+ select PCI_LOCKLESS_CONFIG
select PERF_EVENTS
select RTC_LIB
select RTC_MC146818_LIB
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index 190e718..cfd1a89 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -75,8 +75,8 @@ struct pci_ops pci_root_ops = {
};

/*
- * This interrupt-safe spinlock protects all accesses to PCI
- * configuration space.
+ * This interrupt-safe spinlock protects all accesses to PCI configuration
+ * space, except for the mmconfig (ECAM) based operations.
*/
DEFINE_RAW_SPINLOCK(pci_config_lock);

\
 
 \ /
  Last update: 2017-06-28 22:50    [W:0.205 / U:0.296 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site