On 14 September 2016 at 15:19, Robert Bragg robert@sixbynine.org wrote:
Consistent with the kernel.perf_event_paranoid sysctl option that can allow non-root users to access system wide cpu metrics, this can optionally allow non-root users to access system wide OA counter metrics from Gen graphics hardware.
Signed-off-by: Robert Bragg robert@sixbynine.org
drivers/gpu/drm/i915/i915_drv.h | 1 + drivers/gpu/drm/i915/i915_perf.c | 45 +++++++++++++++++++++++++++++++++++++++- 2 files changed, 45 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index f5ddf70..eaba7a9 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -2142,6 +2142,7 @@ struct drm_i915_private { bool initialized;
struct kobject *metrics_kobj;
struct ctl_table_header *sysctl_header; struct mutex lock; struct list_head streams;diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c index e890c38..38b13fa 100644 --- a/drivers/gpu/drm/i915/i915_perf.c +++ b/drivers/gpu/drm/i915/i915_perf.c @@ -62,6 +62,8 @@ #define POLL_FREQUENCY 200 #define POLL_PERIOD (NSEC_PER_SEC / POLL_FREQUENCY)
+static u32 i915_perf_stream_paranoid = true;
/* The maximum exponent the hardware accepts is 63 (essentially it selects one
- of the 64bit timestamp bits to trigger reports from) but there's currently
- no known use case for sampling as infrequently as once per 47 thousand years.
@@ -1170,7 +1172,13 @@ int i915_perf_open_ioctl_locked(struct drm_device *dev, } }
if (!specific_ctx && !capable(CAP_SYS_ADMIN)) {
/* Similar to perf's kernel.perf_paranoid_cpu sysctl option* we check a dev.i915.perf_stream_paranoid sysctl option* to determine if it's ok to access system wide OA counters* without CAP_SYS_ADMIN privileges.*/if (!specific_ctx &&i915_perf_stream_paranoid && !capable(CAP_SYS_ADMIN)) { DRM_ERROR("Insufficient privileges to open system-wide i915 perf stream\n"); ret = -EACCES; goto err_ctx;@@ -1417,6 +1425,37 @@ void i915_perf_unregister(struct drm_i915_private *dev_priv) dev_priv->perf.metrics_kobj = NULL; }
+static struct ctl_table oa_table[] = {
{.procname = "perf_stream_paranoid",.data = &i915_perf_stream_paranoid,.maxlen = sizeof(i915_perf_stream_paranoid),.mode = 0644,.proc_handler = proc_dointvec,
If this really is just a bool, why not:
.proc_handler = proc_dointvec_minmax, .extra1 = &zero, .extra2 = &one
Reviewed-by: Matthew Auld matthew.auld@intel.com