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authorIngo Molnar <mingo@elte.hu>2010-11-26 15:07:02 +0100
committerIngo Molnar <mingo@elte.hu>2010-11-26 15:07:02 +0100
commit6c869e772c72d509d0db243a56c205ef48a29baf (patch)
tree9a290f1742526a8816f94560cb09bc0a09c910de /arch
parente4e91ac410356da3a518188f371e9d3b52ee38ee (diff)
parentee6dcfa40a50fe12a3ae0fb4d2653c66c3ed6556 (diff)
Merge branch 'perf/urgent' into perf/core
Conflicts: arch/x86/kernel/apic/hw_nmi.c Merge reason: Resolve conflict, queue up dependent patch. Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch')
-rw-r--r--arch/x86/Kconfig2
-rw-r--r--arch/x86/kernel/apic/hw_nmi.c7
-rw-r--r--arch/x86/kernel/cpu/perf_event.c20
-rw-r--r--arch/x86/kernel/entry_64.S2
-rw-r--r--arch/x86/kernel/hw_breakpoint.c4
5 files changed, 31 insertions, 4 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index e8327686d3c5..e330da21b84f 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -21,7 +21,7 @@ config X86
select HAVE_UNSTABLE_SCHED_CLOCK
select HAVE_IDE
select HAVE_OPROFILE
- select HAVE_PERF_EVENTS if (!M386 && !M486)
+ select HAVE_PERF_EVENTS
select HAVE_IRQ_WORK
select HAVE_IOREMAP_PROT
select HAVE_KPROBES
diff --git a/arch/x86/kernel/apic/hw_nmi.c b/arch/x86/kernel/apic/hw_nmi.c
index 3e25afe9a62a..a0e71cb4fa9c 100644
--- a/arch/x86/kernel/apic/hw_nmi.c
+++ b/arch/x86/kernel/apic/hw_nmi.c
@@ -17,9 +17,6 @@
#include <linux/nmi.h>
#include <linux/module.h>
-/* For reliability, we're prepared to waste bits here. */
-static DECLARE_BITMAP(backtrace_mask, NR_CPUS) __read_mostly;
-
#ifdef CONFIG_HARDLOCKUP_DETECTOR
u64 hw_nmi_get_sample_period(void)
{
@@ -27,6 +24,10 @@ u64 hw_nmi_get_sample_period(void)
}
#endif
+
+/* For reliability, we're prepared to waste bits here. */
+static DECLARE_BITMAP(backtrace_mask, NR_CPUS) __read_mostly;
+
#ifdef arch_trigger_all_cpu_backtrace
void arch_trigger_all_cpu_backtrace(void)
{
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 5273c7b90b8b..7c1a4c35fd41 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -372,6 +372,20 @@ static void release_pmc_hardware(void) {}
#endif
+static bool check_hw_exists(void)
+{
+ u64 val, val_new = 0;
+ int ret = 0;
+
+ val = 0xabcdUL;
+ ret |= checking_wrmsrl(x86_pmu.perfctr, val);
+ ret |= rdmsrl_safe(x86_pmu.perfctr, &val_new);
+ if (ret || val != val_new)
+ return false;
+
+ return true;
+}
+
static void reserve_ds_buffers(void);
static void release_ds_buffers(void);
@@ -1363,6 +1377,12 @@ void __init init_hw_perf_events(void)
pmu_check_apic();
+ /* sanity check that the hardware exists or is emulated */
+ if (!check_hw_exists()) {
+ pr_cont("Broken PMU hardware detected, software events only.\n");
+ return;
+ }
+
pr_cont("%s PMU driver.\n", x86_pmu.name);
if (x86_pmu.quirks)
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index fe2690d71c0c..e3ba417e8697 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -295,6 +295,7 @@ ENDPROC(native_usergs_sysret64)
.endm
/* save partial stack frame */
+ .pushsection .kprobes.text, "ax"
ENTRY(save_args)
XCPT_FRAME
cld
@@ -334,6 +335,7 @@ ENTRY(save_args)
ret
CFI_ENDPROC
END(save_args)
+ .popsection
ENTRY(save_rest)
PARTIAL_FRAME 1 REST_SKIP+8
diff --git a/arch/x86/kernel/hw_breakpoint.c b/arch/x86/kernel/hw_breakpoint.c
index ff15c9dcc25d..42c594254507 100644
--- a/arch/x86/kernel/hw_breakpoint.c
+++ b/arch/x86/kernel/hw_breakpoint.c
@@ -433,6 +433,10 @@ static int __kprobes hw_breakpoint_handler(struct die_args *args)
dr6_p = (unsigned long *)ERR_PTR(args->err);
dr6 = *dr6_p;
+ /* If it's a single step, TRAP bits are random */
+ if (dr6 & DR_STEP)
+ return NOTIFY_DONE;
+
/* Do an early return if no trap bits are set in DR6 */
if ((dr6 & DR_TRAP_BITS) == 0)
return NOTIFY_DONE;