kernel/git/stable/linux.git/arch/powerpc/perf, branch linux-3.15.y

powerpc/perf: Fix MMCR2 handling for EBB

2014-08-07T23:53:51+00:00

commit 8903461c9bc56fcb041fb92d054e2529951770b6 upstream. In the recent commit b50a6c584bb4 "Clear MMCR2 when enabling PMU", I screwed up the handling of MMCR2 for tasks using EBB. We must make sure we set MMCR2 *before* ebb_switch_in(), otherwise we overwrite the value of MMCR2 that userspace may have written. That potentially breaks a task that uses EBB and manually uses MMCR2 for event freezing. Fixes: b50a6c584bb4 ("powerpc/perf: Clear MMCR2 when enabling PMU") Signed-off-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman

powerpc/perf: Clear MMCR2 when enabling PMU

2014-07-17T23:23:12+00:00

commit b50a6c584bb47b370f84bfd746770c0bbe7129b7 upstream. On POWER8 when switching to a KVM guest we set bits in MMCR2 to freeze the PMU counters. Aside from on boot they are then never reset, resulting in stuck perf counters for any user in the guest or host. We now set MMCR2 to 0 whenever enabling the PMU, which provides a sane state for perf to use the PMU counters under either the guest or the host. This was manifesting as a bug with ppc64_cpu --frequency: $ sudo ppc64_cpu --frequency WARNING: couldn't run on cpu 0 WARNING: couldn't run on cpu 8 ... WARNING: couldn't run on cpu 144 WARNING: couldn't run on cpu 152 min: 18446744073.710 GHz (cpu -1) max: 0.000 GHz (cpu -1) avg: 0.000 GHz The command uses a perf counter to measure CPU cycles over a fixed amount of time, in order to approximate the frequency of the machine. The counters were returning zero once a guest was started, regardless of weather it was still running or had been shut down. By dumping the value of MMCR2, it was observed that once a guest is running MMCR2 is set to 1s - which stops counters from running: $ sudo sh -c 'echo p > /proc/sysrq-trigger' CPU: 0 PMU registers, ppmu = POWER8 n_counters = 6 PMC1: 5b635e38 PMC2: 00000000 PMC3: 00000000 PMC4: 00000000 PMC5: 1bf5a646 PMC6: 5793d378 PMC7: deadbeef PMC8: deadbeef MMCR0: 0000000080000000 MMCR1: 000000001e000000 MMCRA: 0000040000000000 MMCR2: fffffffffffffc00 EBBHR: 0000000000000000 EBBRR: 0000000000000000 BESCR: 0000000000000000 SIAR: 00000000000a51cc SDAR: c00000000fc40000 SIER: 0000000001000000 This is done unconditionally in book3s_hv_interrupts.S upon entering the guest, and the original value is only save/restored if the host has indicated it was using the PMU. This is okay, however the user of the PMU needs to ensure that it is in a defined state when it starts using it. Fixes: e05b9b9e5c10 ("powerpc/perf: Power8 PMU support") Signed-off-by: Joel Stanley Acked-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman

powerpc/perf: Add PPMU_ARCH_207S define

2014-07-17T23:23:12+00:00

commit 4d9690dd56b0d18f2af8a9d4a279cb205aae3345 upstream. Instead of separate bits for every POWER8 PMU feature, have a single one for v2.07 of the architecture. This saves us adding a MMCR2 define for a future patch. Signed-off-by: Joel Stanley Acked-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman

powerpc/perf: Never program book3s PMCs with values >= 0x80000000

2014-07-17T23:23:12+00:00

commit f56029410a13cae3652d1f34788045c40a13ffc7 upstream. We are seeing a lot of PMU warnings on POWER8: Can't find PMC that caused IRQ Looking closer, the active PMC is 0 at this point and we took a PMU exception on the transition from negative to 0. Some versions of POWER8 have an issue where they edge detect and not level detect PMC overflows. A number of places program the PMC with (0x80000000 - period_left), where period_left can be negative. We can either fix all of these or just ensure that period_left is always >= 1. This patch takes the second option. Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman

powerpc/perf/hv-24x7: Catalog version number is be64, not be32

2014-04-28T06:31:50+00:00

The catalog version number was changed from a be32 (with proceeding 32bits of padding) to a be64, update the code to treat it as a be64 Signed-off-by: Cody P Schafer Signed-off-by: Benjamin Herrenschmidt

powerpc/perf/hv-24x7: Remove [static 4096], sparse chokes on it

2014-04-28T03:11:27+00:00

Signed-off-by: Cody P Schafer Signed-off-by: Benjamin Herrenschmidt

powerpc/perf/hv-24x7: Use (unsigned long) not (u32) values when calling plpar_hcall_norets()

2014-04-28T03:11:26+00:00

Signed-off-by: Cody P Schafer Signed-off-by: Benjamin Herrenschmidt

powerpc/perf/hv-gpci: Make device attr static

2014-04-28T03:11:26+00:00

Signed-off-by: Cody P Schafer Signed-off-by: Benjamin Herrenschmidt

powerpc/perf/hv_gpci: Probe failures use pr_debug(), and padding reduced

2014-04-28T03:11:25+00:00

fixup for "powerpc/perf: Add support for the hv gpci (get performance counter info) interface". Makes the "not enabled" message less awful (and hidden unless debugging). Signed-off-by: Cody P Schafer Signed-off-by: Benjamin Herrenschmidt

powerpc/perf/hv_24x7: Probe errors changed to pr_debug(), padding fixed

2014-04-28T03:11:25+00:00

fixup for "powerpc/perf: Add support for the hv 24x7 interface" Makes the "not enabled" message less awful (and hides it in most cases). Signed-off-by: Cody P Schafer Signed-off-by: Benjamin Herrenschmidt