linux-kernel - [PATCH 2/4] perf, x86: Fix handle

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 31 Aug 2010 22:56:44 -0400
From:	Don Zickus <dzickus@...hat.com>
To:	mingo@...e.hu
Cc:	peterz@...radead.org, robert.richter@....com, gorcunov@...il.com,
	fweisbec@...il.com, linux-kernel@...r.kernel.org,
	ying.huang@...el.com, ming.m.lin@...el.com, yinghai@...nel.org,
	andi@...stfloor.org, Peter Zijlstra <a.p.zijlstra@...llo.nl>
Subject: [PATCH 2/4] perf, x86: Fix handle_irq return values

From: Peter Zijlstra <a.p.zijlstra@...llo.nl>

Now that we rely on the number of handled overflows, ensure all handle_irq
implementations actually return the right number.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@...llo.nl>
Tested-by: Don Zickus <dzickus@...hat.com>
LKML-Reference: <1282228033.2605.204.camel@...top>
---
 arch/x86/kernel/cpu/perf_event_intel.c |    9 +++++++--
 arch/x86/kernel/cpu/perf_event_p4.c    |    2 +-
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c
index d8d86d0..4539b4b 100644
--- a/arch/x86/kernel/cpu/perf_event_intel.c
+++ b/arch/x86/kernel/cpu/perf_event_intel.c
@@ -713,6 +713,7 @@ static int intel_pmu_handle_irq(struct pt_regs *regs)
 	struct cpu_hw_events *cpuc;
 	int bit, loops;
 	u64 ack, status;
+	int handled = 0;
 
 	perf_sample_data_init(&data, 0);
 
@@ -743,12 +744,16 @@ again:
 	/*
 	 * PEBS overflow sets bit 62 in the global status register
 	 */
-	if (__test_and_clear_bit(62, (unsigned long *)&status))
+	if (__test_and_clear_bit(62, (unsigned long *)&status)) {
+		handled++;
 		x86_pmu.drain_pebs(regs);
+	}
 
 	for_each_set_bit(bit, (unsigned long *)&status, X86_PMC_IDX_MAX) {
 		struct perf_event *event = cpuc->events[bit];
 
+		handled++;
+
 		if (!test_bit(bit, cpuc->active_mask))
 			continue;
 
@@ -772,7 +777,7 @@ again:
 
 done:
 	intel_pmu_enable_all(0);
-	return 1;
+	return handled;
 }
 
 static struct event_constraint *
diff --git a/arch/x86/kernel/cpu/perf_event_p4.c b/arch/x86/kernel/cpu/perf_event_p4.c
index febb12c..d470c91 100644
--- a/arch/x86/kernel/cpu/perf_event_p4.c
+++ b/arch/x86/kernel/cpu/perf_event_p4.c
@@ -690,7 +690,7 @@ static int p4_pmu_handle_irq(struct pt_regs *regs)
 		inc_irq_stat(apic_perf_irqs);
 	}
 
-	return handled > 0;
+	return handled;
 }
 
 /*
-- 
1.7.2.2

--
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/