-----Original Message----- From: Tvrtko Ursulin <[email protected]> Sent: Thursday, October 5, 2023 1:55 AM To: Cavitt, Jonathan <[email protected]>; [email protected] Cc: Dutt, Sudeep <[email protected]>; Chang, Yu bruce <[email protected]>; [email protected]; Iddamsetty, Aravind <[email protected]>; Yang, Fei <[email protected]>; Shyti, Andi <[email protected]>; Harrison, John C <[email protected]>; Das, Nirmoy <[email protected]>; Krzysztofik, Janusz <[email protected]>; Roper, Matthew D <[email protected]> Subject: Re: [PATCH v5 2/4] drm/i915: Define and use GuC and CTB TLB invalidation routines > > > On 04/10/2023 19:36, Jonathan Cavitt wrote: > > From: Prathap Kumar Valsan <[email protected]> > > > > The GuC firmware had defined the interface for Translation Look-Aside > > Buffer (TLB) invalidation. We should use this interface when > > invalidating the engine and GuC TLBs. > > Add additional functionality to intel_gt_invalidate_tlb, invalidating > > the GuC TLBs and falling back to GT invalidation when the GuC is > > disabled. > > The invalidation is done by sending a request directly to the GuC > > tlb_lookup that invalidates the table. The invalidation is submitted as > > a wait request and is performed in the CT event handler. This means we > > cannot perform this TLB invalidation path if the CT is not enabled. > > If the request isn't fulfilled in two seconds, this would constitute > > an error in the invalidation as that would constitute either a lost > > request or a severe GuC overload. > > The tlb_lookup table is allocated as an xarray because the set of > > pending TLB invalidations may have no upper bound. The consequence of > > this is that all actions interfacting with this table need to use the > > xarray functions, such as xa_alloc_cyclic_irq for array insertion. > > > > With this new invalidation routine, we can perform GuC-based GGTT > > invalidations. GuC-based GGTT invalidation is incompatible with > > MMIO invalidation so we should not perform MMIO invalidation when > > GuC-based GGTT invalidation is expected. > > This respun (series) includes changes some but not all points that I > have raised, or at least asked about in the last round. There were no > replies, to explain either that I was wrong, or whatever, against the > points left un-modified. Some of those I raised more than once. > > And while I appreciate addressing review feedback and quick respins, I > don't enjoy the silence on the unaddressed parts since that is not how > the review should work. Therefore I will not be reviewing this version > until all review comments are dealt with one way or the other.
I went back through your previous revision notes just now. AFAICT, the only revision note I did not address in this patch series pertains to the necessity for if (!intel_guc_ct_enabled(&guc->ct)) in guc_send_invalidate_tlb. However, I cannot see where this is guarded against in the code prior, so it still appears necessary. If this is incorrect, please inform me of what I may have missed. I understand it's difficult to see what's changed between revisions, and I recognize that was my fault for not including a cover letter: I was under the impression I was to not include cover letters in upstream patches unless I had some additional information to provide, but the way I write cover letters gives the impression that this is not the case. I added a cover letter to version six that retroactively applies version change notes to all prior revisions. This may have been missed because I accidentally left the dii-client tag (and a stale patch duplicate patch) in the series, so it may have been seen as a series sent to the wrong email address. I'll aim to remove the tag for version seven. -Jonathan Cavitt > > Regards, > > Tvrtko > > > Signed-off-by: Prathap Kumar Valsan <[email protected]> > > Signed-off-by: Bruce Chang <[email protected]> > > Signed-off-by: Chris Wilson <[email protected]> > > Signed-off-by: Umesh Nerlige Ramappa <[email protected]> > > Signed-off-by: Jonathan Cavitt <[email protected]> > > Signed-off-by: Aravind Iddamsetty <[email protected]> > > Signed-off-by: Fei Yang <[email protected]> > > CC: Andi Shyti <[email protected]> > > --- > > drivers/gpu/drm/i915/gt/intel_ggtt.c | 42 ++-- > > drivers/gpu/drm/i915/gt/intel_tlb.c | 14 +- > > .../gpu/drm/i915/gt/uc/abi/guc_actions_abi.h | 33 +++ > > drivers/gpu/drm/i915/gt/uc/intel_guc.h | 22 ++ > > drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c | 6 + > > drivers/gpu/drm/i915/gt/uc/intel_guc_fwif.h | 1 + > > .../gpu/drm/i915/gt/uc/intel_guc_submission.c | 211 +++++++++++++++++- > > 7 files changed, 313 insertions(+), 16 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/gt/intel_ggtt.c > > b/drivers/gpu/drm/i915/gt/intel_ggtt.c > > index 4d7d88b92632b..be8c216d29f91 100644 > > --- a/drivers/gpu/drm/i915/gt/intel_ggtt.c > > +++ b/drivers/gpu/drm/i915/gt/intel_ggtt.c > > @@ -206,22 +206,38 @@ static void gen8_ggtt_invalidate(struct i915_ggtt > > *ggtt) > > intel_uncore_write_fw(uncore, GFX_FLSH_CNTL_GEN6, GFX_FLSH_CNTL_EN); > > } > > > > -static void guc_ggtt_invalidate(struct i915_ggtt *ggtt) > > +static void guc_ggtt_ct_invalidate(struct intel_gt *gt) > > { > > - struct drm_i915_private *i915 = ggtt->vm.i915; > > + struct intel_uncore *uncore = gt->uncore; > > + intel_wakeref_t wakeref; > > > > - gen8_ggtt_invalidate(ggtt); > > + with_intel_runtime_pm_if_active(uncore->rpm, wakeref) { > > + struct intel_guc *guc = >->uc.guc; > > > > - if (GRAPHICS_VER(i915) >= 12) { > > - struct intel_gt *gt; > > + intel_guc_invalidate_tlb(guc); > > + } > > +} > > > > - list_for_each_entry(gt, &ggtt->gt_list, ggtt_link) > > - intel_uncore_write_fw(gt->uncore, > > - GEN12_GUC_TLB_INV_CR, > > - GEN12_GUC_TLB_INV_CR_INVALIDATE); > > - } else { > > - intel_uncore_write_fw(ggtt->vm.gt->uncore, > > - GEN8_GTCR, GEN8_GTCR_INVALIDATE); > > +static void guc_ggtt_invalidate(struct i915_ggtt *ggtt) > > +{ > > + struct drm_i915_private *i915 = ggtt->vm.i915; > > + struct intel_gt *gt; > > + > > + if (!IS_GEN9_LP(i915) && GRAPHICS_VER(i915) < 11) > > + gen8_ggtt_invalidate(ggtt); > > + > > + list_for_each_entry(gt, &ggtt->gt_list, ggtt_link) { > > + if (HAS_GUC_TLB_INVALIDATION(i915) && > > + intel_guc_is_ready(>->uc.guc)) { > > + guc_ggtt_ct_invalidate(gt); > > + } else if (GRAPHICS_VER(i915) >= 12) { > > + intel_uncore_write(gt->uncore, > > + GEN12_GUC_TLB_INV_CR, > > + GEN12_GUC_TLB_INV_CR_INVALIDATE); > > + } else { > > + intel_uncore_write(gt->uncore, > > + GEN8_GTCR, GEN8_GTCR_INVALIDATE); > > + } > > } > > } > > > > @@ -1243,7 +1259,7 @@ static int gen8_gmch_probe(struct i915_ggtt *ggtt) > > ggtt->vm.raw_insert_page = gen8_ggtt_insert_page; > > } > > > > - if (intel_uc_wants_guc(&ggtt->vm.gt->uc)) > > + if (intel_uc_wants_guc_submission(&ggtt->vm.gt->uc)) > > ggtt->invalidate = guc_ggtt_invalidate; > > else > > ggtt->invalidate = gen8_ggtt_invalidate; > > diff --git a/drivers/gpu/drm/i915/gt/intel_tlb.c > > b/drivers/gpu/drm/i915/gt/intel_tlb.c > > index 139608c30d978..a84563c178bc6 100644 > > --- a/drivers/gpu/drm/i915/gt/intel_tlb.c > > +++ b/drivers/gpu/drm/i915/gt/intel_tlb.c > > @@ -12,6 +12,7 @@ > > #include "intel_gt_print.h" > > #include "intel_gt_regs.h" > > #include "intel_tlb.h" > > +#include "uc/intel_guc.h" > > > > /* > > * HW architecture suggest typical invalidation time at 40us, > > @@ -131,11 +132,22 @@ void intel_gt_invalidate_tlb_full(struct intel_gt > > *gt, u32 seqno) > > return; > > > > with_intel_gt_pm_if_awake(gt, wakeref) { > > + struct intel_guc *guc = >->uc.guc; > > + > > mutex_lock(>->tlb.invalidate_lock); > > if (tlb_seqno_passed(gt, seqno)) > > goto unlock; > > > > - mmio_invalidate_full(gt); > > + if (HAS_GUC_TLB_INVALIDATION(gt->i915)) { > > + /* > > + * Only perform GuC TLB invalidation if GuC is ready. > > + * Otherwise, skip invalidation altogeter. > > + */ > > + if (intel_guc_is_ready(guc)) > > + intel_guc_invalidate_tlb_full(guc); > > + } else { > > + mmio_invalidate_full(gt); > > + } > > > > write_seqcount_invalidate(>->tlb.seqno); > > unlock: > > diff --git a/drivers/gpu/drm/i915/gt/uc/abi/guc_actions_abi.h > > b/drivers/gpu/drm/i915/gt/uc/abi/guc_actions_abi.h > > index f359bef046e0b..9dff8012d5e76 100644 > > --- a/drivers/gpu/drm/i915/gt/uc/abi/guc_actions_abi.h > > +++ b/drivers/gpu/drm/i915/gt/uc/abi/guc_actions_abi.h > > @@ -138,6 +138,8 @@ enum intel_guc_action { > > INTEL_GUC_ACTION_REGISTER_CONTEXT_MULTI_LRC = 0x4601, > > INTEL_GUC_ACTION_CLIENT_SOFT_RESET = 0x5507, > > INTEL_GUC_ACTION_SET_ENG_UTIL_BUFF = 0x550A, > > + INTEL_GUC_ACTION_TLB_INVALIDATION = 0x7000, > > + INTEL_GUC_ACTION_TLB_INVALIDATION_DONE = 0x7001, > > INTEL_GUC_ACTION_STATE_CAPTURE_NOTIFICATION = 0x8002, > > INTEL_GUC_ACTION_NOTIFY_FLUSH_LOG_BUFFER_TO_FILE = 0x8003, > > INTEL_GUC_ACTION_NOTIFY_CRASH_DUMP_POSTED = 0x8004, > > @@ -181,4 +183,35 @@ enum intel_guc_state_capture_event_status { > > > > #define INTEL_GUC_STATE_CAPTURE_EVENT_STATUS_MASK 0x000000FF > > > > +#define INTEL_GUC_TLB_INVAL_TYPE_MASK REG_GENMASK(7, 0) > > +#define INTEL_GUC_TLB_INVAL_MODE_MASK REG_GENMASK(11, 8) > > +#define INTEL_GUC_TLB_INVAL_FLUSH_CACHE REG_BIT(31) > > + > > +enum intel_guc_tlb_invalidation_type { > > + INTEL_GUC_TLB_INVAL_FULL = 0x0, > > + INTEL_GUC_TLB_INVAL_GUC = 0x3, > > +}; > > + > > +/* > > + * 0: Heavy mode of Invalidation: > > + * The pipeline of the engine(s) for which the invalidation is targeted to > > is > > + * blocked, and all the in-flight transactions are guaranteed to be > > Globally > > + * Observed before completing the TLB invalidation > > + * 1: Lite mode of Invalidation: > > + * TLBs of the targeted engine(s) are immediately invalidated. > > + * In-flight transactions are NOT guaranteed to be Globally Observed before > > + * completing TLB invalidation. > > + * Light Invalidation Mode is to be used only when > > + * it can be guaranteed (by SW) that the address translations remain > > invariant > > + * for the in-flight transactions across the TLB invalidation. In other > > words, > > + * this mode can be used when the TLB invalidation is intended to clear > > out the > > + * stale cached translations that are no longer in use. Light Invalidation > > Mode > > + * is much faster than the Heavy Invalidation Mode, as it does not wait > > for the > > + * in-flight transactions to be GOd. > > + */ > > +enum intel_guc_tlb_inval_mode { > > + INTEL_GUC_TLB_INVAL_MODE_HEAVY = 0x0, > > + INTEL_GUC_TLB_INVAL_MODE_LITE = 0x1, > > +}; > > + > > #endif /* _ABI_GUC_ACTIONS_ABI_H */ > > diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.h > > b/drivers/gpu/drm/i915/gt/uc/intel_guc.h > > index 6c392bad29c19..d7203ba88b0c0 100644 > > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc.h > > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.h > > @@ -79,6 +79,18 @@ struct intel_guc { > > */ > > atomic_t outstanding_submission_g2h; > > > > + /** @tlb_lookup: xarray to store all pending TLB invalidation requests > > */ > > + struct xarray tlb_lookup; > > + > > + /** > > + * @serial_slot: id to the initial waiter created in tlb_lookup, > > + * which is used only when failed to allocate new waiter. > > + */ > > + u32 serial_slot; > > + > > + /** @next_seqno: the next id (sequence no.) to allocate. */ > > + u32 next_seqno; > > + > > /** @interrupts: pointers to GuC interrupt-managing functions. */ > > struct { > > bool enabled; > > @@ -296,6 +308,11 @@ struct intel_guc { > > #define MAKE_GUC_VER_STRUCT(ver) MAKE_GUC_VER((ver).major, (ver).minor, > > (ver).patch) > > #define GUC_SUBMIT_VER(guc) > > MAKE_GUC_VER_STRUCT((guc)->submission_version) > > > > +struct intel_guc_tlb_wait { > > + struct wait_queue_head wq; > > + bool busy; > > +}; > > + > > static inline struct intel_guc *log_to_guc(struct intel_guc_log *log) > > { > > return container_of(log, struct intel_guc, log); > > @@ -418,6 +435,11 @@ static inline bool intel_guc_is_supported(struct > > intel_guc *guc) > > return intel_uc_fw_is_supported(&guc->fw); > > } > > > > +int intel_guc_invalidate_tlb_full(struct intel_guc *guc); > > +int intel_guc_invalidate_tlb(struct intel_guc *guc); > > +int intel_guc_tlb_invalidation_done(struct intel_guc *guc, const u32 *hxg, > > + u32 size); > > + > > static inline bool intel_guc_is_wanted(struct intel_guc *guc) > > { > > return intel_uc_fw_is_enabled(&guc->fw); > > diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c > > b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c > > index 6e22af31513a5..1ee4d4a988398 100644 > > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c > > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c > > @@ -1115,6 +1115,11 @@ static int ct_process_request(struct intel_guc_ct > > *ct, struct ct_incoming_msg *r > > case INTEL_GUC_ACTION_NOTIFY_EXCEPTION: > > ret = intel_guc_crash_process_msg(guc, action); > > break; > > + case INTEL_GUC_ACTION_TLB_INVALIDATION_DONE: > > + ret = intel_guc_tlb_invalidation_done(ct_to_guc(ct), hxg, > > request->size); > > + if (unlikely(ret)) > > + ct_free_msg(request); > > + break; > > default: > > ret = -EOPNOTSUPP; > > break; > > @@ -1186,6 +1191,7 @@ static int ct_handle_event(struct intel_guc_ct *ct, > > struct ct_incoming_msg *requ > > switch (action) { > > case INTEL_GUC_ACTION_SCHED_CONTEXT_MODE_DONE: > > case INTEL_GUC_ACTION_DEREGISTER_CONTEXT_DONE: > > + case INTEL_GUC_ACTION_TLB_INVALIDATION_DONE: > > g2h_release_space(ct, request->size); > > } > > > > diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_fwif.h > > b/drivers/gpu/drm/i915/gt/uc/intel_guc_fwif.h > > index b4d56eccfb1f0..a7c9874e122a3 100644 > > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_fwif.h > > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_fwif.h > > @@ -22,6 +22,7 @@ > > /* Payload length only i.e. don't include G2H header length */ > > #define G2H_LEN_DW_SCHED_CONTEXT_MODE_SET 2 > > #define G2H_LEN_DW_DEREGISTER_CONTEXT 1 > > +#define G2H_LEN_DW_INVALIDATE_TLB 1 > > > > #define GUC_CONTEXT_DISABLE 0 > > #define GUC_CONTEXT_ENABLE 1 > > diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > > b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > > index 2cce5ec1ff00d..12f79abd889ce 100644 > > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > > @@ -1798,9 +1798,11 @@ static void __guc_reset_context(struct intel_context > > *ce, intel_engine_mask_t st > > > > void intel_guc_submission_reset(struct intel_guc *guc, > > intel_engine_mask_t stalled) > > { > > + struct intel_guc_tlb_wait *wait; > > struct intel_context *ce; > > unsigned long index; > > unsigned long flags; > > + unsigned long i; > > > > if (unlikely(!guc_submission_initialized(guc))) { > > /* Reset called during driver load? GuC not yet initialised! */ > > @@ -1826,6 +1828,14 @@ void intel_guc_submission_reset(struct intel_guc > > *guc, intel_engine_mask_t stall > > > > /* GuC is blown away, drop all references to contexts */ > > xa_destroy(&guc->context_lookup); > > + > > + /* > > + * The full GT reset will have cleared the TLB caches and flushed the > > + * G2H message queue; we can release all the blocked waiters. > > + */ > > + xa_for_each(&guc->tlb_lookup, i, wait) { > > + wake_up(&wait->wq); > > + } > > } > > > > static void guc_cancel_context_requests(struct intel_context *ce) > > @@ -1948,6 +1958,49 @@ void intel_guc_submission_reset_finish(struct > > intel_guc *guc) > > static void destroyed_worker_func(struct work_struct *w); > > static void reset_fail_worker_func(struct work_struct *w); > > > > +static int init_tlb_lookup(struct intel_guc *guc) > > +{ > > + struct intel_guc_tlb_wait *wait; > > + int err; > > + > > + if (!HAS_GUC_TLB_INVALIDATION(guc_to_gt(guc)->i915)) > > + return 0; > > + > > + xa_init_flags(&guc->tlb_lookup, XA_FLAGS_ALLOC); > > + > > + wait = kzalloc(sizeof(*wait), GFP_KERNEL); > > + if (!wait) > > + return -ENOMEM; > > + > > + init_waitqueue_head(&wait->wq); > > + > > + /* Preallocate a shared id for use under memory pressure. */ > > + err = xa_alloc_cyclic_irq(&guc->tlb_lookup, &guc->serial_slot, wait, > > + xa_limit_32b, &guc->next_seqno, GFP_KERNEL); > > + if (err == -ENOMEM) { > > + kfree(wait); > > + return err; > > + } > > + > > + return 0; > > +} > > + > > +static void fini_tlb_lookup(struct intel_guc *guc) > > +{ > > + struct intel_guc_tlb_wait *wait; > > + > > + if (!HAS_GUC_TLB_INVALIDATION(guc_to_gt(guc)->i915)) > > + return; > > + > > + wait = xa_load(&guc->tlb_lookup, guc->serial_slot); > > + if (wait) { > > + GEM_BUG_ON(wait->busy); > > + kfree(wait); > > + } > > + > > + xa_destroy(&guc->tlb_lookup); > > +} > > + > > /* > > * Set up the memory resources to be shared with the GuC (via the GGTT) > > * at firmware loading time. > > @@ -1966,11 +2019,15 @@ int intel_guc_submission_init(struct intel_guc *guc) > > return ret; > > } > > > > + ret = init_tlb_lookup(guc); > > + if (ret) > > + goto destroy_pool; > > + > > guc->submission_state.guc_ids_bitmap = > > bitmap_zalloc(NUMBER_MULTI_LRC_GUC_ID(guc), GFP_KERNEL); > > if (!guc->submission_state.guc_ids_bitmap) { > > ret = -ENOMEM; > > - goto destroy_pool; > > + goto destroy_tlb; > > } > > > > guc->timestamp.ping_delay = (POLL_TIME_CLKS / gt->clock_frequency + 1) > > * HZ; > > @@ -1979,9 +2036,10 @@ int intel_guc_submission_init(struct intel_guc *guc) > > > > return 0; > > > > +destroy_tlb: > > + fini_tlb_lookup(guc); > > destroy_pool: > > guc_lrc_desc_pool_destroy_v69(guc); > > - > > return ret; > > } > > > > @@ -1994,6 +2052,7 @@ void intel_guc_submission_fini(struct intel_guc *guc) > > guc_lrc_desc_pool_destroy_v69(guc); > > i915_sched_engine_put(guc->sched_engine); > > bitmap_free(guc->submission_state.guc_ids_bitmap); > > + fini_tlb_lookup(guc); > > guc->submission_initialized = false; > > } > > > > @@ -4624,6 +4683,154 @@ g2h_context_lookup(struct intel_guc *guc, u32 > > ctx_id) > > return ce; > > } > > > > +static void wait_wake_outstanding_tlb_g2h(struct intel_guc *guc, u32 seqno) > > +{ > > + struct intel_guc_tlb_wait *wait; > > + unsigned long flags; > > + > > + xa_lock_irqsave(&guc->tlb_lookup, flags); > > + wait = xa_load(&guc->tlb_lookup, seqno); > > + > > + /* We received a response after the waiting task did exit with a > > timeout */ > > + if (wait) > > + wake_up(&wait->wq); > > + else > > + drm_dbg(&guc_to_gt(guc)->i915->drm, > > + "Stale TLB invalidation response with seqno %d\n", > > seqno); > > + > > + xa_unlock_irqrestore(&guc->tlb_lookup, flags); > > +} > > + > > +int intel_guc_tlb_invalidation_done(struct intel_guc *guc, const u32 *hxg, > > u32 size) > > +{ > > + u32 seqno, hxg_len, len; > > + > > + hxg_len = size - GUC_CTB_MSG_MIN_LEN; > > + len = hxg_len - GUC_HXG_MSG_MIN_LEN; > > + > > + /* Check for underflow */ > > + if (unlikely(len < 1 || len > size)) > > + return -EPROTO; > > + > > + seqno = hxg[GUC_HXG_MSG_MIN_LEN]; > > + wait_wake_outstanding_tlb_g2h(guc, seqno); > > + return 0; > > +} > > + > > +static long must_wait_woken(struct wait_queue_entry *wq_entry, long > > timeout) > > +{ > > + /* > > + * This is equivalent to wait_woken() with the exception that > > + * we do not wake up early if the kthread task has been completed. > > + * As we are called from page reclaim in any task context, > > + * we may be invoked from stopped kthreads, but we *must* > > + * complete the wait from the HW . > > + * > > + * A second problem is that since we are called under reclaim > > + * and wait_woken() inspected the thread state, it makes an invalid > > + * assumption that all PF_KTHREAD tasks have set_kthread_struct() > > + * called upon them, and will trigger a GPF in is_kthread_should_stop(). > > + */ > > + do { > > + set_current_state(TASK_UNINTERRUPTIBLE); > > + if (wq_entry->flags & WQ_FLAG_WOKEN) > > + break; > > + > > + timeout = schedule_timeout(timeout); > > + } while (timeout); > > + __set_current_state(TASK_RUNNING); > > + > > + /* See wait_woken() and woken_wake_function() */ > > + smp_store_mb(wq_entry->flags, wq_entry->flags & ~WQ_FLAG_WOKEN); > > + > > + return timeout; > > +} > > + > > +static int guc_send_invalidate_tlb(struct intel_guc *guc, u32 type) > > +{ > > + struct intel_guc_tlb_wait _wq, *wq = &_wq; > > + DEFINE_WAIT_FUNC(wait, woken_wake_function); > > + struct intel_gt *gt = guc_to_gt(guc); > > + int err; > > + u32 seqno; > > + u32 action[] = { > > + INTEL_GUC_ACTION_TLB_INVALIDATION, > > + 0, > > + REG_FIELD_PREP(INTEL_GUC_TLB_INVAL_TYPE_MASK, type) | > > + REG_FIELD_PREP(INTEL_GUC_TLB_INVAL_MODE_MASK, > > + INTEL_GUC_TLB_INVAL_MODE_HEAVY) | > > + INTEL_GUC_TLB_INVAL_FLUSH_CACHE, > > + }; > > + u32 size = ARRAY_SIZE(action); > > + > > + if (!intel_guc_ct_enabled(&guc->ct)) > > + return -EINVAL; > > + > > + init_waitqueue_head(&_wq.wq); > > + > > + if (xa_alloc_cyclic_irq(&guc->tlb_lookup, &seqno, wq, > > + xa_limit_32b, &guc->next_seqno, > > + GFP_ATOMIC | __GFP_NOWARN) < 0) { > > + /* Under severe memory pressure? Serialise TLB allocations */ > > + xa_lock_irq(&guc->tlb_lookup); > > + wq = xa_load(&guc->tlb_lookup, guc->serial_slot); > > + wait_event_lock_irq(wq->wq, > > + !READ_ONCE(wq->busy), > > + guc->tlb_lookup.xa_lock); > > + /* > > + * Update wq->busy under lock to ensure only one waiter can > > + * issue the TLB invalidation command using the serial slot at a > > + * time. The condition is set to true before releasing the lock > > + * so that other caller continue to wait until woken up again. > > + */ > > + wq->busy = true; > > + xa_unlock_irq(&guc->tlb_lookup); > > + > > + seqno = guc->serial_slot; > > + } > > + > > + action[1] = seqno; > > + > > + add_wait_queue(&wq->wq, &wait); > > + > > + err = intel_guc_send_busy_loop(guc, action, size, > > G2H_LEN_DW_INVALIDATE_TLB, true); > > + if (err) > > + goto out; > > + > > + /* > > + * GuC has a timeout of 1ms for a TLB invalidation response from GAM. > > On a > > + * timeout GuC drops the request and has no mechanism to notify the > > host about > > + * the timeout. There is also no mechanism for determining the number > > of > > + * any/all messages in the CT channel. Ergo, keep a larger timeout > > that accounts > > + * for this individual timeout and the max number of outstanding > > invalidation > > + * requests that can be queued in CT buffer. > > + */ > > +#define OUTSTANDING_GUC_TIMEOUT_PERIOD (HZ * 2) > > + if (!must_wait_woken(&wait, OUTSTANDING_GUC_TIMEOUT_PERIOD)) { > > + gt_err(gt, > > + "TLB invalidation response timed out for seqno %u\n", > > seqno); > > + err = -ETIME; > > + } > > +out: > > + remove_wait_queue(&wq->wq, &wait); > > + if (seqno != guc->serial_slot) > > + xa_erase_irq(&guc->tlb_lookup, seqno); > > + > > + return err; > > +} > > + > > +/* Full TLB invalidation */ > > +int intel_guc_invalidate_tlb_full(struct intel_guc *guc) > > +{ > > + return guc_send_invalidate_tlb(guc, INTEL_GUC_TLB_INVAL_FULL); > > +} > > + > > +/* GuC TLB Invalidation: Invalidate the TLB's of GuC itself. */ > > +int intel_guc_invalidate_tlb(struct intel_guc *guc) > > +{ > > + return guc_send_invalidate_tlb(guc, INTEL_GUC_TLB_INVAL_GUC); > > +} > > + > > int intel_guc_deregister_done_process_msg(struct intel_guc *guc, > > const u32 *msg, > > u32 len) >
