Re: [PATCH v2 07/11] powerpc: add a shared interface to get gpci version and capabilities
From: Cody P Schafer
Date: Tue Feb 25 2014 - 16:21:29 EST
On 02/24/2014 07:33 PM, Michael Ellerman wrote:
[PATCH v2 07/11] powerpc: add a shared interface to get gpci version and capabilities
All the patches that touch perf should be "powerpc/perf: foo"
Ok.
On Fri, 2014-14-02 at 22:02:11 UTC, Cody P Schafer wrote:
...
I realise this is a fairly small patch but a changelog is still nice. You could
for example mention that we don't currently use .ga, .expanded or .lab but
we're adding the logic anyway because ...
Well, we do use them to expose some more information to the user (via
sysfs attributes). Always nice to know what capabilities are enabled.
But sure, I can explain why each bit in that structure is a good idea.
Signed-off-by: Cody P Schafer <cody@xxxxxxxxxxxxxxxxxx>
---
arch/powerpc/perf/hv-common.c | 39 +++++++++++++++++++++++++++++++++++++++
arch/powerpc/perf/hv-common.h | 17 +++++++++++++++++
2 files changed, 56 insertions(+)
create mode 100644 arch/powerpc/perf/hv-common.c
create mode 100644 arch/powerpc/perf/hv-common.h
diff --git a/arch/powerpc/perf/hv-common.c b/arch/powerpc/perf/hv-common.c
new file mode 100644
index 0000000..47e02b3
--- /dev/null
+++ b/arch/powerpc/perf/hv-common.c
@@ -0,0 +1,39 @@
+#include <asm/io.h>
+#include <asm/hvcall.h>
+
+#include "hv-gpci.h"
+#include "hv-common.h"
+
+unsigned long hv_perf_caps_get(struct hv_perf_caps *caps)
+{
+ unsigned long r;
+ struct p {
+ struct hv_get_perf_counter_info_params params;
+ struct cv_system_performance_capabilities caps;
+ } __packed __aligned(sizeof(uint64_t));
+
+ struct p arg = {
+ .params = {
+ .counter_request = cpu_to_be32(
+ CIR_SYSTEM_PERFORMANCE_CAPABILITIES),
+ .starting_index = cpu_to_be32(-1),
+ .counter_info_version_in = 0,
+ }
+ };
+
+ r = plpar_hcall_norets(H_GET_PERF_COUNTER_INFO,
+ virt_to_phys(&arg), sizeof(arg));
+
+ if (r)
+ return r;
+
+ pr_devel("capability_mask: 0x%x\n", arg.caps.capability_mask);
+
+ caps->version = arg.params.counter_info_version_out;
+ caps->collect_privileged = !!arg.caps.perf_collect_privileged;
+ caps->ga = !!(arg.caps.capability_mask & CV_CM_GA);
+ caps->expanded = !!(arg.caps.capability_mask & CV_CM_EXPANDED);
+ caps->lab = !!(arg.caps.capability_mask & CV_CM_LAB);
+
+ return r;
+}
diff --git a/arch/powerpc/perf/hv-common.h b/arch/powerpc/perf/hv-common.h
new file mode 100644
index 0000000..7e615bd
--- /dev/null
+++ b/arch/powerpc/perf/hv-common.h
@@ -0,0 +1,17 @@
+#ifndef LINUX_POWERPC_PERF_HV_COMMON_H_
+#define LINUX_POWERPC_PERF_HV_COMMON_H_
+
+#include <linux/types.h>
+
+struct hv_perf_caps {
+ u16 version;
+ u16 collect_privileged:1,
+ ga:1,
+ expanded:1,
+ lab:1,
+ unused:12;
+};
+
+unsigned long hv_perf_caps_get(struct hv_perf_caps *caps);
+
+#endif
--
1.8.5.4
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