| Message ID | 20161028021430.2177-10-robert@sixbynine.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, 2016-10-27 at 19:14 -0700, Robert Bragg 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> > Reviewed-by: Matthew Auld <matthew.auld@intel.com> > --- > drivers/gpu/drm/i915/i915_drv.h | 1 + > drivers/gpu/drm/i915/i915_perf.c | 50 +++++++++++++++++++++++++++++++++++++++- > 2 files changed, 50 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h > index 01438fb..a138f86 100644 > --- a/drivers/gpu/drm/i915/i915_drv.h > +++ b/drivers/gpu/drm/i915/i915_drv.h > @@ -2171,6 +2171,7 @@ 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 8d07c41..4e42073 100644 > --- a/drivers/gpu/drm/i915/i915_perf.c > +++ b/drivers/gpu/drm/i915/i915_perf.c > @@ -64,6 +64,11 @@ > #define POLL_FREQUENCY 200 > #define POLL_PERIOD (NSEC_PER_SEC / POLL_FREQUENCY) > > +/* for sysctl proc_dointvec_minmax of dev.i915.perf_stream_paranoid */ > +static int zero; > +static int one = 1; > +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. > @@ -1207,7 +1212,13 @@ i915_perf_open_ioctl_locked(struct drm_i915_private *dev_priv, > } > } > > - 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; > @@ -1454,6 +1465,39 @@ 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_minmax, > + .extra1 = &zero, > + .extra2 = &one, > + }, > + {} > +}; > + > +static struct ctl_table i915_root[] = { > + { > + .procname = "i915", > + .maxlen = 0, > + .mode = 0555, > + .child = oa_table, > + }, > + {} > +}; > + > +static struct ctl_table dev_root[] = { > + { > + .procname = "dev", > + .maxlen = 0, > + .mode = 0555, > + .child = i915_root, > + }, > + {} > +}; > + > void i915_perf_init(struct drm_i915_private *dev_priv) > { > if (!IS_HASWELL(dev_priv)) > @@ -1484,6 +1528,8 @@ void i915_perf_init(struct drm_i915_private *dev_priv) > dev_priv->perf.oa.n_builtin_sets = > i915_oa_n_builtin_metric_sets_hsw; > > + dev_priv->perf.sysctl_header = register_sysctl_table(dev_root); > + > dev_priv->perf.initialized = true; > } > > @@ -1492,6 +1538,8 @@ void i915_perf_fini(struct drm_i915_private *dev_priv) > if (!dev_priv->perf.initialized) > return; > > + unregister_sysctl_table(dev_priv->perf.sysctl_header); > + > memset(&dev_priv->perf.oa.ops, 0, sizeof(dev_priv->perf.oa.ops)); > dev_priv->perf.initialized = false; > } Looks fine. Reviewed-by: Sourab Gupta <sourab.gupta@intel.com>
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 01438fb..a138f86 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -2171,6 +2171,7 @@ 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 8d07c41..4e42073 100644 --- a/drivers/gpu/drm/i915/i915_perf.c +++ b/drivers/gpu/drm/i915/i915_perf.c @@ -64,6 +64,11 @@ #define POLL_FREQUENCY 200 #define POLL_PERIOD (NSEC_PER_SEC / POLL_FREQUENCY) +/* for sysctl proc_dointvec_minmax of dev.i915.perf_stream_paranoid */ +static int zero; +static int one = 1; +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. @@ -1207,7 +1212,13 @@ i915_perf_open_ioctl_locked(struct drm_i915_private *dev_priv, } } - 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; @@ -1454,6 +1465,39 @@ 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_minmax, + .extra1 = &zero, + .extra2 = &one, + }, + {} +}; + +static struct ctl_table i915_root[] = { + { + .procname = "i915", + .maxlen = 0, + .mode = 0555, + .child = oa_table, + }, + {} +}; + +static struct ctl_table dev_root[] = { + { + .procname = "dev", + .maxlen = 0, + .mode = 0555, + .child = i915_root, + }, + {} +}; + void i915_perf_init(struct drm_i915_private *dev_priv) { if (!IS_HASWELL(dev_priv)) @@ -1484,6 +1528,8 @@ void i915_perf_init(struct drm_i915_private *dev_priv) dev_priv->perf.oa.n_builtin_sets = i915_oa_n_builtin_metric_sets_hsw; + dev_priv->perf.sysctl_header = register_sysctl_table(dev_root); + dev_priv->perf.initialized = true; } @@ -1492,6 +1538,8 @@ void i915_perf_fini(struct drm_i915_private *dev_priv) if (!dev_priv->perf.initialized) return; + unregister_sysctl_table(dev_priv->perf.sysctl_header); + memset(&dev_priv->perf.oa.ops, 0, sizeof(dev_priv->perf.oa.ops)); dev_priv->perf.initialized = false; }