dm_test_ism...e_and_cancel(9)

💅 dm_test_ism_dispatch_hysteresis_schedule_and_cancel — a Kernel API Manual moment 🎀

okay so bestie, welcome to the Kernel API Manual ✨ — today's main character is dm_test_ism_dispatch_hysteresis_schedule_and_cancel(9), and she is literally here to cover the HYSTERESIS_WAITING dispatch arms. no cap, that's the whole vibe. 🦋

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✨ NAME ✨

dm_test_ism_dispatch_hysteresis_schedule_and_cancel — cover the HYSTERESIS_WAITING dispatch arms 💖

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🌸 SYNOPSIS 🌸

void dm_test_ism_dispatch_hysteresis_schedule_and_cancel (struct kunit
test );

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🎀 ARGUMENTS 🎀

• test — the KUnit test context, aka the little group chat this test is living in 🫶

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🔥 DESCRIPTION 🔥

so here's the lore, bestie. ENTER_IDLE_REQUESTED moves FULL_POWER_RUNNING -> HYSTERESIS_WAITING. slay, transition ate. 💅

then the current-state arm of dm_ism_dispatch_power_state does its thing: it records the idle timestamp, computes a (non-zero!) idle-allow delay, and schedules the delayed worker. iconic behaviour, honestly. ⭐

after that, a subsequent BEGIN_CURSOR_UPDATE (-> HYSTERESIS_BUSY) exercises the previous-state arm, which cancels that pending worker. so we're out here testing the schedule and the cancel — hence the name, iykyk. 😭

and the important bit: neither arm reaches the DC-dependent idle-optimization commit path. so like, don't go looking for it, it's not invited to this party 🙈

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👑 SEE ALSO 👑

🧚 Kernel file 🧚

./drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_ism_test.c

🌈 the whole friend group 🌈

• dm_test_ism_idle_delay_entry_count_exceeds_history_size(9)
• dm_test_ism_init_sets_initial_state(9)
• dm_test_ism_fini_after_init(9)
• dm_test_ism_set_last_idle_ts_updates_timestamp(9)
• dm_test_ism_insert_record_basic(9)
• dm_test_ism_insert_record_wraps_around(9)
• dm_test_ism_trigger_event_valid_transition(9)
• dm_test_ism_trigger_event_invalid_transition(9)
• dm_test_dispatch_next_event_hyst_wait_no_delay(9)
• dm_test_dispatch_next_event_hyst_wait_with_delay(9)
• dm_test_dispatch_next_event_opt_idle_no_sso_delay(9)
• dm_test_dispatch_next_event_opt_idle_with_sso_delay(9)
• dm_test_dispatch_next_event_timer_aborted(9)
• dm_test_dispatch_next_event_no_action_state(9)
• dm_test_ism_commit_event_no_state(9)
• dm_test_ism_commit_event_cursor_transition(9)
• dm_test_ism_commit_event_invalid_event(9)
• dm_test_ism_force_full_power(9)
• dm_test_ism_disable_enable_cycle(9)
• dm_test_ism_dispatch_optimized_idle_defers_sso(9)

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💀 reminder bestie: these are cross-references, not bonus levels. read them if you wanna know the neighbours, but this page is this page. periodt. 🍓

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and that's a wrap on our little manpage date 💜 — brought to you by source ./drivers/gpu/drm/amd/display/..., dated October 2026, page dm_test_ism...e_and_cancel(9). go forth and test those arms, queen 👑✨