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authorOlof Johansson <olof@lixom.net>2013-07-12 19:59:39 +0200
committerOlof Johansson <olof@lixom.net>2013-07-12 19:59:39 +0200
commitf4b96f5e4ff8d86699c851c10245e102809b0331 (patch)
treef766102263bed71738431cabb4d4f6f086005cd8 /arch/x86/kernel/nmi.c
parentARM: omap2: add select of TI_PRIV_EDMA (diff)
parentARM: OMAP2+: omap2plus_defconfig: Enable appended DTB support (diff)
downloadlinux-f4b96f5e4ff8d86699c851c10245e102809b0331.tar.xz
linux-f4b96f5e4ff8d86699c851c10245e102809b0331.zip
Merge tag 'omap-for-v3.11/fixes-for-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes
Omap fixes and minor defconfig updates that would be good to get in before -rc1. * tag 'omap-for-v3.11/fixes-for-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap: ARM: OMAP2+: omap2plus_defconfig: Enable appended DTB support ARM: OMAP2+: Enable TI_EDMA in omap2plus_defconfig ARM: OMAP2+: omap2plus_defconfig: enable DRA752 thermal support by default ARM: OMAP2+: omap2plus_defconfig: enable TI bandgap driver ARM: OMAP2+: devices: remove duplicated include from devices.c ARM: OMAP3: igep0020: Set DSS pins in correct mux mode. ARM: OMAP2+: N900: enable N900-specific drivers even if device tree is enabled ARM: OMAP2+: Cocci spatch "ptr_ret.spatch" ARM: OMAP2+: Remove obsolete Makefile line ARM: OMAP5: Enable Cortex A15 errata 798181 ARM: scu: provide inline dummy functions when SCU is not present ARM: OMAP4: sleep: build OMAP4 specific functions only for OMAP4 ARM: OMAP2+: timer: initialize before using oh_name Signed-off-by: Olof Johansson <olof@lixom.net> Add/move/change conflicts in arch/arm/mach-omap2/Kconfig resolved.
Diffstat (limited to 'arch/x86/kernel/nmi.c')
-rw-r--r--arch/x86/kernel/nmi.c36
1 files changed, 34 insertions, 2 deletions
diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c
index 60308053fdb2..0920212e6159 100644
--- a/arch/x86/kernel/nmi.c
+++ b/arch/x86/kernel/nmi.c
@@ -14,6 +14,7 @@
#include <linux/kprobes.h>
#include <linux/kdebug.h>
#include <linux/nmi.h>
+#include <linux/debugfs.h>
#include <linux/delay.h>
#include <linux/hardirq.h>
#include <linux/slab.h>
@@ -29,6 +30,9 @@
#include <asm/nmi.h>
#include <asm/x86_init.h>
+#define CREATE_TRACE_POINTS
+#include <trace/events/nmi.h>
+
struct nmi_desc {
spinlock_t lock;
struct list_head head;
@@ -82,6 +86,15 @@ __setup("unknown_nmi_panic", setup_unknown_nmi_panic);
#define nmi_to_desc(type) (&nmi_desc[type])
+static u64 nmi_longest_ns = 1 * NSEC_PER_MSEC;
+static int __init nmi_warning_debugfs(void)
+{
+ debugfs_create_u64("nmi_longest_ns", 0644,
+ arch_debugfs_dir, &nmi_longest_ns);
+ return 0;
+}
+fs_initcall(nmi_warning_debugfs);
+
static int __kprobes nmi_handle(unsigned int type, struct pt_regs *regs, bool b2b)
{
struct nmi_desc *desc = nmi_to_desc(type);
@@ -96,8 +109,27 @@ static int __kprobes nmi_handle(unsigned int type, struct pt_regs *regs, bool b2
* can be latched at any given time. Walk the whole list
* to handle those situations.
*/
- list_for_each_entry_rcu(a, &desc->head, list)
- handled += a->handler(type, regs);
+ list_for_each_entry_rcu(a, &desc->head, list) {
+ u64 before, delta, whole_msecs;
+ int decimal_msecs, thishandled;
+
+ before = local_clock();
+ thishandled = a->handler(type, regs);
+ handled += thishandled;
+ delta = local_clock() - before;
+ trace_nmi_handler(a->handler, (int)delta, thishandled);
+
+ if (delta < nmi_longest_ns)
+ continue;
+
+ nmi_longest_ns = delta;
+ whole_msecs = do_div(delta, (1000 * 1000));
+ decimal_msecs = do_div(delta, 1000) % 1000;
+ printk_ratelimited(KERN_INFO
+ "INFO: NMI handler (%ps) took too long to run: "
+ "%lld.%03d msecs\n", a->handler, whole_msecs,
+ decimal_msecs);
+ }
rcu_read_unlock();