| Message ID | 1467132967-19751-1-git-send-email-david.s.gordon@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 28/06/16 17:56, Dave Gordon wrote: > Part spin-wait, part sleep-wait. > Plus one example of where it might be used. > > Signed-off-by: Dave Gordon <david.s.gordon@intel.com> > --- > drivers/gpu/drm/i915/i915_guc_submission.c | 2 +- > drivers/gpu/drm/i915/intel_drv.h | 10 ++++++++++ > 2 files changed, 11 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c > index 355b647..ff99910 100644 > --- a/drivers/gpu/drm/i915/i915_guc_submission.c > +++ b/drivers/gpu/drm/i915/i915_guc_submission.c > @@ -98,7 +98,7 @@ static int host2guc_action(struct intel_guc *guc, u32 *data, u32 len) > I915_WRITE(HOST2GUC_INTERRUPT, HOST2GUC_TRIGGER); > > /* No HOST2GUC command should take longer than 10ms */ > - ret = wait_for_atomic(host2guc_action_response(dev_priv, &status), 10); > + ret = wait_for_hybrid(host2guc_action_response(dev_priv, &status), 10, 10); > if (status != GUC2HOST_STATUS_SUCCESS) { > /* > * Either the GuC explicitly returned an error (which > diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h > index 3156d8d..096e07c 100644 > --- a/drivers/gpu/drm/i915/intel_drv.h > +++ b/drivers/gpu/drm/i915/intel_drv.h > @@ -103,6 +103,16 @@ > #define wait_for_atomic(COND, MS) _wait_for_atomic((COND), (MS) * 1000) > #define wait_for_atomic_us(COND, US) _wait_for_atomic((COND), (US)) > > +/* Hybrid wait: > + * first spin-wait for up to <US> microseconds, > + * if <COND> still not true, sleep-wait for MS milliseconds > + */ > +#define wait_for_hybrid(COND, US, MS) ({ \ > + int ret__ = wait_for_atomic_us(COND, US); \ > + if (ret__) ret__ = wait_for(COND, MS); \ > + ret__; \ > + }) > + > #define KHz(x) (1000 * (x)) > #define MHz(x) KHz(1000 * (x)) Wouldn't harm anything if you know typical GuC response time is under 10us and 10ms timeout is backed with some documentation. Another idea could be a wait_for variant which takes those values, so typical and maximum response time, and then it could decide statically in the macro what to do. Regards, Tvrtko
diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c index 355b647..ff99910 100644 --- a/drivers/gpu/drm/i915/i915_guc_submission.c +++ b/drivers/gpu/drm/i915/i915_guc_submission.c @@ -98,7 +98,7 @@ static int host2guc_action(struct intel_guc *guc, u32 *data, u32 len) I915_WRITE(HOST2GUC_INTERRUPT, HOST2GUC_TRIGGER); /* No HOST2GUC command should take longer than 10ms */ - ret = wait_for_atomic(host2guc_action_response(dev_priv, &status), 10); + ret = wait_for_hybrid(host2guc_action_response(dev_priv, &status), 10, 10); if (status != GUC2HOST_STATUS_SUCCESS) { /* * Either the GuC explicitly returned an error (which diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index 3156d8d..096e07c 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -103,6 +103,16 @@ #define wait_for_atomic(COND, MS) _wait_for_atomic((COND), (MS) * 1000) #define wait_for_atomic_us(COND, US) _wait_for_atomic((COND), (US)) +/* Hybrid wait: + * first spin-wait for up to <US> microseconds, + * if <COND> still not true, sleep-wait for MS milliseconds + */ +#define wait_for_hybrid(COND, US, MS) ({ \ + int ret__ = wait_for_atomic_us(COND, US); \ + if (ret__) ret__ = wait_for(COND, MS); \ + ret__; \ + }) + #define KHz(x) (1000 * (x)) #define MHz(x) KHz(1000 * (x))
Part spin-wait, part sleep-wait. Plus one example of where it might be used. Signed-off-by: Dave Gordon <david.s.gordon@intel.com> --- drivers/gpu/drm/i915/i915_guc_submission.c | 2 +- drivers/gpu/drm/i915/intel_drv.h | 10 ++++++++++ 2 files changed, 11 insertions(+), 1 deletion(-)