kernel.git/arch/arm64/kernel/perf_event.c, branch linux-4.9.y

arm64: perf: Disable PMU while processing counter overflows

2021-06-30T12:49:19Z

commit 3cce50dfec4a5b0414c974190940f47dd32c6dee upstream. The arm64 PMU updates the event counters and reprograms the counters in the overflow IRQ handler without disabling the PMU. This could potentially cause skews in for group counters, where the overflowed counters may potentially loose some event counts, while they are reprogrammed. To prevent this, disable the PMU while we process the counter overflows and enable it right back when we are done. This patch also moves the PMU stop/start routines to avoid a forward declaration. Suggested-by: Mark Rutland Cc: Will Deacon Acked-by: Mark Rutland Signed-off-by: Suzuki K Poulose Signed-off-by: Will Deacon Signed-off-by: Aman Priyadarshi Signed-off-by: Greg Kroah-Hartman

arm64: perf: set suppress_bind_attrs flag to true

2019-01-26T08:38:33Z

[ Upstream commit 81e9fa8bab381f8b6eb04df7cdf0f71994099bd4 ] The armv8_pmuv3 driver doesn't have a remove function, and when the test 'CONFIG_DEBUG_TEST_DRIVER_REMOVE=y' is enabled, the following Call trace can be seen. [ 1.424287] Failed to register pmu: armv8_pmuv3, reason -17 [ 1.424870] WARNING: CPU: 0 PID: 1 at ../kernel/events/core.c:11771 perf_event_sysfs_init+0x98/0xdc [ 1.425220] Modules linked in: [ 1.425531] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 4.19.0-rc7-next-20181012-00003-ge7a97b1ad77b-dirty #35 [ 1.425951] Hardware name: linux,dummy-virt (DT) [ 1.426212] pstate: 80000005 (Nzcv daif -PAN -UAO) [ 1.426458] pc : perf_event_sysfs_init+0x98/0xdc [ 1.426720] lr : perf_event_sysfs_init+0x98/0xdc [ 1.426908] sp : ffff00000804bd50 [ 1.427077] x29: ffff00000804bd50 x28: ffff00000934e078 [ 1.427429] x27: ffff000009546000 x26: 0000000000000007 [ 1.427757] x25: ffff000009280710 x24: 00000000ffffffef [ 1.428086] x23: ffff000009408000 x22: 0000000000000000 [ 1.428415] x21: ffff000009136008 x20: ffff000009408730 [ 1.428744] x19: ffff80007b20b400 x18: 000000000000000a [ 1.429075] x17: 0000000000000000 x16: 0000000000000000 [ 1.429418] x15: 0000000000000400 x14: 2e79726f74636572 [ 1.429748] x13: 696420656d617320 x12: 656874206e692065 [ 1.430060] x11: 6d616e20656d6173 x10: 2065687420687469 [ 1.430335] x9 : ffff00000804bd50 x8 : 206e6f7361657220 [ 1.430610] x7 : 2c3376756d705f38 x6 : ffff00000954d7ce [ 1.430880] x5 : 0000000000000000 x4 : 0000000000000000 [ 1.431226] x3 : 0000000000000000 x2 : ffffffffffffffff [ 1.431554] x1 : 4d151327adc50b00 x0 : 0000000000000000 [ 1.431868] Call trace: [ 1.432102] perf_event_sysfs_init+0x98/0xdc [ 1.432382] do_one_initcall+0x6c/0x1a8 [ 1.432637] kernel_init_freeable+0x1bc/0x280 [ 1.432905] kernel_init+0x18/0x160 [ 1.433115] ret_from_fork+0x10/0x18 [ 1.433297] ---[ end trace 27fd415390eb9883 ]--- Rework to set suppress_bind_attrs flag to avoid removing the device when CONFIG_DEBUG_TEST_DRIVER_REMOVE=y, since there's no real reason to remove the armv8_pmuv3 driver. Cc: Arnd Bergmann Co-developed-by: Arnd Bergmann Signed-off-by: Anders Roxell Signed-off-by: Will Deacon Signed-off-by: Sasha Levin

arm64: perf: Ignore exclude_hv when kernel is running in HYP

2018-04-13T17:47:57Z

[ Upstream commit 78a19cfdf37d19002c83c8790853c1cc10feccdc ] commit d98ecdaca296 ("arm64: perf: Count EL2 events if the kernel is running in HYP") returns -EINVAL when perf system call perf_event_open is called with exclude_hv != exclude_kernel. This change breaks applications on VHE enabled ARMv8.1 platforms. The issue was observed with HHVM application, which calls perf_event_open with exclude_hv = 1 and exclude_kernel = 0. There is no separate hypervisor privilege level when VHE is enabled, the host kernel runs at EL2. So when VHE is enabled, we should ignore exclude_hv from the application. This behaviour is consistent with PowerPC where the exclude_hv is ignored when the hypervisor is not present and with x86 where this flag is ignored. Signed-off-by: Ganapatrao Kulkarni [will: added comment to justify the behaviour of exclude_hv] Signed-off-by: Will Deacon Signed-off-by: Catalin Marinas Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

KVM: arm64: Fix the issues when guest PMCCFILTR is configured

2016-11-18T09:06:58Z

KVM calls kvm_pmu_set_counter_event_type() when PMCCFILTR is configured. But this function can't deals with PMCCFILTR correctly because the evtCount bits of PMCCFILTR, which is reserved 0, conflits with the SW_INCR event type of other PMXEVTYPER registers. To fix it, when eventsel == 0, this function shouldn't return immediately; instead it needs to check further if select_idx is ARMV8_PMU_CYCLE_IDX. Another issue is that KVM shouldn't copy the eventsel bits of PMCCFILTER blindly to attr.config. Instead it ought to convert the request to the "cpu cycle" event type (i.e. 0x11). To support this patch and to prevent duplicated definitions, a limited set of ARMv8 perf event types were relocated from perf_event.c to asm/perf_event.h. Cc: stable@vger.kernel.org # 4.6+ Acked-by: Will Deacon Signed-off-by: Wei Huang Signed-off-by: Marc Zyngier

arm64: pmu: Hoist pmu platform device name

2016-09-16T16:11:34Z

Move the PMU name into a common header file so it may be referenced by other users. Signed-off-by: Jeremy Linton Signed-off-by: Will Deacon

arm64: pmu: Probe default hw/cache counters

2016-09-16T16:11:33Z

ARMv8 machines can identify the micro/arch defined counters that are available on a machine. Add all these counters to the default armv8 perf map. At run-time disable the counters which are not available on the given PMU. Signed-off-by: Jeremy Linton Acked-by: Will Deacon Signed-off-by: Will Deacon

arm64: pmu: add fallback probe table

2016-09-16T16:11:33Z

In preparation for ACPI support, add a pmu_probe_info table to the arm_pmu_device_probe() call. This table gets used when probing in the absence of a devicetree node for PMU. Signed-off-by: Mark Salter Signed-off-by: Jeremy Linton Signed-off-by: Will Deacon

arm64: perf: move to common attr_group fields

2016-09-09T13:51:51Z

By using a common attr_groups array, the common arm_pmu code can set up common files (e.g. cpumask) for us in subsequent patches. Signed-off-by: Mark Rutland Cc: Will Deacon Signed-off-by: Will Deacon

arm64: perf: Use the builtin_platform_driver

2016-08-22T09:00:48Z

Use the builtin_platform_driver() to simplify code. Signed-off-by: Kefeng Wang Signed-off-by: Will Deacon

arm64: perf: don't expose CHAIN event in sysfs

2016-04-25T14:05:24Z

The CHAIN event allows two 32-bit counters to be treated as a single 64-bit counter, under certain allocation restrictions on the PMU. Whilst userspace could theoretically create CHAIN events using the raw event syntax, we don't really want to advertise this in sysfs, since it's useless in isolation. This patch removes the event from our /sys entries. Reported-by: Mark Rutland Signed-off-by: Will Deacon