Commit 8aa8c2d4 authored by Lucas De Marchi's avatar Lucas De Marchi
Browse files

drm/xe/rtp: Drop sentinels from arg to xe_rtp_process_to_sr() 



There's a mismatch on API: while xe_rtp_process_to_sr() processes
entries until an entry without name, the active tracking with
xe_rtp_process_ctx_enable_active_tracking() needs to use the number of
elements. The number of elements is taken everywhere using ARRAY_SIZE(),
but that will have one entry too many. This leads to the following
warning, as reported by lkp:

   drivers/gpu/drm/xe/xe_tuning.c: In function 'xe_tuning_dump':
>> include/drm/drm_print.h:228:31: warning: '%s' directive argument is null [-Wformat-overflow=]
     228 |         drm_printf((printer), "%.*s" fmt, (indent), "\t\t\t\t\tX", ##__VA_ARGS__)
         |                               ^~~~~~
   drivers/gpu/drm/xe/xe_tuning.c:226:17: note: in expansion of macro 'drm_printf_indent'
     226 |                 drm_printf_indent(p, 1, "%s\n", engine_tunings[idx].name);
         |                 ^~~~~~~~~~~~~~~~~

That's because it will still process the last entry when tracking the
active tunings. The same issue exists in the WAs. Change
xe_rtp_process_to_sr() to also take the number of elements so the empty
entry can be removed and the warning should go away. Fixing on the
active-tracking side would more fragile as the it would need a `- 1`
everywhere and continue to use a different approach for number of
elements.

Aside from the warning, it's a non-issue as there would always be enough
bits allocated and the last entry would never be active since
xe_rtp_process_to_sr() stops on the sentinel.

Reported-by: default avatarkernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202503021906.P2MwAvyK-lkp@intel.com/


Cc: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Reviewed-by: default avatarTvrtko Ursulin <tvrtko.ursulin@igalia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250306-fix-print-warning-v1-1-979c3dc03c0d@intel.com


Signed-off-by: default avatarLucas De Marchi <lucas.demarchi@intel.com>
parent 89f8d10f

drivers/gpu/drm/xe/tests/xe_rtp_test.c

+1 −1
Original line number Diff line number Diff line
@@ -320,7 +320,7 @@ static void xe_rtp_process_to_sr_tests(struct kunit *test) 
		count_rtp_entries++;



	xe_rtp_process_ctx_enable_active_tracking(&ctx, &active, count_rtp_entries);

	xe_rtp_process_to_sr(&ctx, param->entries, reg_sr);

	xe_rtp_process_to_sr(&ctx, param->entries, count_rtp_entries, reg_sr);



	xa_for_each(&reg_sr->xa, idx, sre) {

		if (idx == param->expected_reg.addr)

drivers/gpu/drm/xe/xe_hw_engine.c

+2 −4
Original line number Diff line number Diff line
@@ -400,10 +400,9 @@ xe_hw_engine_setup_default_lrc_state(struct xe_hw_engine *hwe) 
					   PREEMPT_GPGPU_THREAD_GROUP_LEVEL)),

		  XE_RTP_ENTRY_FLAG(FOREACH_ENGINE)

		},

		{}

	};



	xe_rtp_process_to_sr(&ctx, lrc_setup, &hwe->reg_lrc);

	xe_rtp_process_to_sr(&ctx, lrc_setup, ARRAY_SIZE(lrc_setup), &hwe->reg_lrc);

}



static void
@@ -459,10 +458,9 @@ hw_engine_setup_default_state(struct xe_hw_engine *hwe) 
		  XE_RTP_ACTIONS(SET(CSFE_CHICKEN1(0), CS_PRIORITY_MEM_READ,

				     XE_RTP_ACTION_FLAG(ENGINE_BASE)))

		},

		{}

	};



	xe_rtp_process_to_sr(&ctx, engine_entries, &hwe->reg_sr);

	xe_rtp_process_to_sr(&ctx, engine_entries, ARRAY_SIZE(engine_entries), &hwe->reg_sr);

}



static const struct engine_info *find_engine_info(enum xe_engine_class class, int instance)

drivers/gpu/drm/xe/xe_reg_whitelist.c

+2 −2
Original line number Diff line number Diff line
@@ -88,7 +88,6 @@ static const struct xe_rtp_entry_sr register_whitelist[] = { 
				   RING_FORCE_TO_NONPRIV_ACCESS_RD |

				   RING_FORCE_TO_NONPRIV_RANGE_4))

	},

	{}

};



static void whitelist_apply_to_hwe(struct xe_hw_engine *hwe)
@@ -137,7 +136,8 @@ void xe_reg_whitelist_process_engine(struct xe_hw_engine *hwe) 
{

	struct xe_rtp_process_ctx ctx = XE_RTP_PROCESS_CTX_INITIALIZER(hwe);



	xe_rtp_process_to_sr(&ctx, register_whitelist, &hwe->reg_whitelist);

	xe_rtp_process_to_sr(&ctx, register_whitelist, ARRAY_SIZE(register_whitelist),

			     &hwe->reg_whitelist);

	whitelist_apply_to_hwe(hwe);

}

drivers/gpu/drm/xe/xe_rtp.c

+5 −1
Original line number Diff line number Diff line
@@ -237,6 +237,7 @@ static void rtp_mark_active(struct xe_device *xe, 
 *                        the save-restore argument.

 * @ctx: The context for processing the table, with one of device, gt or hwe

 * @entries: Table with RTP definitions

 * @n_entries: Number of entries to process, usually ARRAY_SIZE(entries)

 * @sr: Save-restore struct where matching rules execute the action. This can be

 *      viewed as the "coalesced view" of multiple the tables. The bits for each

 *      register set are expected not to collide with previously added entries
@@ -247,6 +248,7 @@ static void rtp_mark_active(struct xe_device *xe, 
 */

void xe_rtp_process_to_sr(struct xe_rtp_process_ctx *ctx,

			  const struct xe_rtp_entry_sr *entries,

			  size_t n_entries,

			  struct xe_reg_sr *sr)

{

	const struct xe_rtp_entry_sr *entry;
@@ -259,7 +261,9 @@ void xe_rtp_process_to_sr(struct xe_rtp_process_ctx *ctx, 
	if (IS_SRIOV_VF(xe))

		return;



	for (entry = entries; entry && entry->name; entry++) {

	xe_assert(xe, entries);



	for (entry = entries; entry - entries < n_entries; entry++) {

		bool match = false;



		if (entry->flags & XE_RTP_ENTRY_FLAG_FOREACH_ENGINE) {

drivers/gpu/drm/xe/xe_rtp.h

+1 −1
Original line number Diff line number Diff line
@@ -430,7 +430,7 @@ void xe_rtp_process_ctx_enable_active_tracking(struct xe_rtp_process_ctx *ctx, 


void xe_rtp_process_to_sr(struct xe_rtp_process_ctx *ctx,

			  const struct xe_rtp_entry_sr *entries,

			  struct xe_reg_sr *sr);

			  size_t n_entries, struct xe_reg_sr *sr);



void xe_rtp_process(struct xe_rtp_process_ctx *ctx,

		    const struct xe_rtp_entry *entries);