From 3c90e42a01426262f0cd166bc01b45c05562640d Mon Sep 17 00:00:00 2001 From: Shuicheng Lin Date: Wed, 9 Sep 2026 16:21:01 +0000 Subject: [PATCH] drm/xe/shrinker: Return the freed page count through a parameter MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit __xe_shrinker_walk() and xe_shrinker_walk() return either the number of pages freed or a negative error, so the two cannot be reported at once. On error the pages already freed are dropped, and since xe_shrinker_scan() only accumulates non-negative returns while *scanned is updated by pointer, the shrinker tells mm that it scanned without freeing. Accumulate the count into a caller-provided counter and return only the status, so an error no longer discards what the walk had freed. Fixes: 00c8efc3180f ("drm/xe: Add a shrinker for xe bos") Assisted-by: Claude:claude-opus-5 Reviewed-by: Thomas Hellström Cc: Matthew Brost Link: https://patch.msgid.link/20260909162102.1097006-2-shuicheng.lin@intel.com Signed-off-by: Shuicheng Lin (cherry picked from commit d7aac1a0235a6ce41e30cec385e2db8c33dad12d) Signed-off-by: Rodrigo Vivi --- drivers/gpu/drm/xe/xe_shrinker.c | 62 ++++++++++++++------------------ 1 file changed, 26 insertions(+), 36 deletions(-) diff --git a/drivers/gpu/drm/xe/xe_shrinker.c b/drivers/gpu/drm/xe/xe_shrinker.c index 83374cd57660..89445cd20238 100644 --- a/drivers/gpu/drm/xe/xe_shrinker.c +++ b/drivers/gpu/drm/xe/xe_shrinker.c @@ -54,13 +54,14 @@ xe_shrinker_mod_pages(struct xe_shrinker *shrinker, long shrinkable, long purgea write_unlock(&shrinker->lock); } -static s64 __xe_shrinker_walk(struct xe_device *xe, +static int __xe_shrinker_walk(struct xe_device *xe, struct ttm_operation_ctx *ctx, const struct xe_bo_shrink_flags flags, - unsigned long to_scan, unsigned long *scanned) + unsigned long to_scan, unsigned long *scanned, + unsigned long *freed) { unsigned int mem_type; - s64 freed = 0, lret; + s64 lret; for (mem_type = XE_PL_SYSTEM; mem_type <= XE_PL_TT; ++mem_type) { struct ttm_resource_manager *man = ttm_manager_type(&xe->ttm, mem_type); @@ -82,7 +83,7 @@ static s64 __xe_shrinker_walk(struct xe_device *xe, if (lret < 0) return lret; - freed += lret; + *freed += lret; if (*scanned >= to_scan) break; } @@ -90,7 +91,7 @@ static s64 __xe_shrinker_walk(struct xe_device *xe, xe_assert(xe, !IS_ERR(ttm_bo)); } - return freed; + return 0; } /* @@ -99,40 +100,35 @@ static s64 __xe_shrinker_walk(struct xe_device *xe, * add writeback. This avoids stalls and explicit writebacks with light or * moderate memory pressure. */ -static s64 xe_shrinker_walk(struct xe_device *xe, +static int xe_shrinker_walk(struct xe_device *xe, struct ttm_operation_ctx *ctx, const struct xe_bo_shrink_flags flags, - unsigned long to_scan, unsigned long *scanned) + unsigned long to_scan, unsigned long *scanned, + unsigned long *freed) { bool no_wait_gpu = true; struct xe_bo_shrink_flags save_flags = flags; - s64 lret, freed; + int ret; swap(no_wait_gpu, ctx->no_wait_gpu); save_flags.writeback = false; - lret = __xe_shrinker_walk(xe, ctx, save_flags, to_scan, scanned); + ret = __xe_shrinker_walk(xe, ctx, save_flags, to_scan, scanned, freed); swap(no_wait_gpu, ctx->no_wait_gpu); - if (lret < 0 || *scanned >= to_scan) - return lret; + if (ret || *scanned >= to_scan) + return ret; - freed = lret; if (!ctx->no_wait_gpu) { - lret = __xe_shrinker_walk(xe, ctx, save_flags, to_scan, scanned); - if (lret < 0) - return lret; - freed += lret; - if (*scanned >= to_scan) - return freed; + ret = __xe_shrinker_walk(xe, ctx, save_flags, to_scan, scanned, + freed); + if (ret || *scanned >= to_scan) + return ret; } - if (flags.writeback) { - lret = __xe_shrinker_walk(xe, ctx, flags, to_scan, scanned); - if (lret < 0) - return lret; - freed += lret; - } + if (flags.writeback) + ret = __xe_shrinker_walk(xe, ctx, flags, to_scan, scanned, + freed); - return freed; + return ret; } static unsigned long @@ -214,7 +210,6 @@ static unsigned long xe_shrinker_scan(struct shrinker *shrink, struct shrink_con bool runtime_pm; bool purgeable; bool can_backup = !!(sc->gfp_mask & __GFP_FS); - s64 lret; nr_to_scan = sc->nr_to_scan; @@ -225,12 +220,9 @@ static unsigned long xe_shrinker_scan(struct shrinker *shrink, struct shrink_con /* Might need runtime PM. Try to wake early if it looks like it. */ runtime_pm = xe_shrinker_runtime_pm_get(shrinker, false, nr_to_scan, can_backup); - if (purgeable && nr_scanned < nr_to_scan) { - lret = xe_shrinker_walk(shrinker->xe, &ctx, shrink_flags, - nr_to_scan, &nr_scanned); - if (lret >= 0) - freed += lret; - } + if (purgeable && nr_scanned < nr_to_scan) + xe_shrinker_walk(shrinker->xe, &ctx, shrink_flags, + nr_to_scan, &nr_scanned, &freed); sc->nr_scanned = nr_scanned; if (nr_scanned >= nr_to_scan || !can_backup) @@ -242,10 +234,8 @@ static unsigned long xe_shrinker_scan(struct shrinker *shrink, struct shrink_con shrink_flags.purge = false; - lret = xe_shrinker_walk(shrinker->xe, &ctx, shrink_flags, - nr_to_scan, &nr_scanned); - if (lret >= 0) - freed += lret; + xe_shrinker_walk(shrinker->xe, &ctx, shrink_flags, + nr_to_scan, &nr_scanned, &freed); sc->nr_scanned = nr_scanned; out: