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Yes, the existing wait is 2s which seems to be overkill. > > Suggested-by: Matthew Brost Reviewed-by: Matthew Brost > Signed-off-by: Michal Wajdeczko > --- > drivers/gpu/drm/xe/xe_guc_ct.c | 12 +++++++----- > 1 file changed, 7 insertions(+), 5 deletions(-) > > diff --git a/drivers/gpu/drm/xe/xe_guc_ct.c b/drivers/gpu/drm/xe/xe_guc_ct.c > index dfbf76037b04..d4111124cd5f 100644 > --- a/drivers/gpu/drm/xe/xe_guc_ct.c > +++ b/drivers/gpu/drm/xe/xe_guc_ct.c > @@ -32,6 +32,7 @@ > #include "xe_guc_tlb_inval.h" > #include "xe_map.h" > #include "xe_pm.h" > +#include "xe_sleep.h" > #include "xe_sriov_vf.h" > #include "xe_trace_guc.h" > > @@ -1101,7 +1102,8 @@ static int dequeue_one_g2h(struct xe_guc_ct *ct); > */ > static bool guc_ct_send_wait_for_retry(struct xe_guc_ct *ct, u32 len, > u32 g2h_len, struct g2h_fence *g2h_fence, > - unsigned int *sleep_period_ms) > + unsigned int *sleep_period_ms, > + unsigned int *sleep_total_ms) > { > struct xe_device *xe = ct_to_xe(ct); > > @@ -1115,15 +1117,14 @@ static bool guc_ct_send_wait_for_retry(struct xe_guc_ct *ct, u32 len, > if (!h2g_has_room(ct, len + GUC_CTB_HDR_LEN)) { > struct guc_ctb *h2g = &ct->ctbs.h2g; > > - if (*sleep_period_ms == 1024) > + if (*sleep_total_ms > 1000) > return false; > > trace_xe_guc_ct_h2g_flow_control(xe, h2g->info.head, h2g->info.tail, > h2g->info.size, > h2g->info.space, > len + GUC_CTB_HDR_LEN); > - msleep(*sleep_period_ms); > - *sleep_period_ms <<= 1; > + xe_sleep_exponential_ms(sleep_period_ms, 64); > } else { > struct xe_device *xe = ct_to_xe(ct); > struct guc_ctb *g2h = &ct->ctbs.g2h; > @@ -1161,6 +1162,7 @@ static int guc_ct_send_locked(struct xe_guc_ct *ct, const u32 *action, u32 len, > { > struct xe_gt *gt = ct_to_gt(ct); > unsigned int sleep_period_ms = 1; > + unsigned int sleep_total_ms = 0; > int ret; > > xe_gt_assert(gt, !g2h_len || !g2h_fence); > @@ -1173,7 +1175,7 @@ static int guc_ct_send_locked(struct xe_guc_ct *ct, const u32 *action, u32 len, > > if (unlikely(ret == -EBUSY)) { > if (!guc_ct_send_wait_for_retry(ct, len, g2h_len, g2h_fence, > - &sleep_period_ms)) > + &sleep_period_ms, &sleep_total_ms)) > goto broken; > goto try_again; > } > -- > 2.47.1 >