From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3D86842A9B; Tue, 27 May 2025 17:49:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748368191; cv=none; b=WeNMozryn6cv2Qo8UDU9ZfoyPSXX9plPvAn1iXm5HZIroDKrttqwaN0/XXr2Mu4ulY2ZNUHWLJWcQwCWlGdSOF5vWfzZ/evSrhE4V1aR5djxFZJySHILqliAgDV/2OSW093iYSp42yZJWlK7bRkk1P5qyEjmg6M2muZPPWzxGQU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748368191; c=relaxed/simple; bh=TsMvn1a3uyFs70ifyaPK22nINvXPAuPi4AYpW703t+M=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WsLBhws2UTj+dQcHFPzOvGjTCoXZWnCVtl+5o4+h2cSOaca5XmRFwLd7VPodXMpHQjplyvev/iY+whjxFQcW5OgDx2UFSIXv34eaMRPe2i6x+SWoNjFj8f6zjiIulTFd7pDRs5PCH3HINbD4+DX07u9FHNW3iPV9cB9kW2x9KFA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Un6n9Etq; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Un6n9Etq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2BAD1C4CEE9; Tue, 27 May 2025 17:49:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1748368190; bh=TsMvn1a3uyFs70ifyaPK22nINvXPAuPi4AYpW703t+M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Un6n9EtqmMa4mPmUGsifZsbf4/7mMEOzZe4yFsXBWlrTDjKbraCwRy3DTDalUpbbd ASVcvuUuxPrDv8XhMckSM8PL7MyMjj+6RrelgxDRHVVeluTBqBrQlv/xMtCFQd6eeF LOchZsnpUvYs+arBmcHDhWuKLQwANz+kqPKVnA6I= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Lucas De Marchi , Rodrigo Vivi , Vinay Belgaumkar , Sasha Levin Subject: [PATCH 6.14 627/783] drm/xe: Add locks in gtidle code Date: Tue, 27 May 2025 18:27:04 +0200 Message-ID: <20250527162538.683470736@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250527162513.035720581@linuxfoundation.org> References: <20250527162513.035720581@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Vinay Belgaumkar [ Upstream commit d160dc6f53914d729be7fcb7afbd0e9e6a3725b2 ] The update of the residency values needs to be protected by a lock to avoid multiple entrypoints, for example when multiple userspace clients read the sysfs file. Other in-kernel clients are going to be added to sample these values, making the problem worse. Protect those updates with a raw_spinlock so it can be called by future integration with perf pmu. Suggested-by: Lucas De Marchi Cc: Rodrigo Vivi Cc: Lucas De Marchi Signed-off-by: Vinay Belgaumkar Reviewed-by: Lucas De Marchi Link: https://patchwork.freedesktop.org/patch/msgid/20250110173308.2412232-2-lucas.demarchi@intel.com Signed-off-by: Lucas De Marchi Signed-off-by: Sasha Levin --- drivers/gpu/drm/xe/xe_gt_idle.c | 23 ++++++++++++++++++++--- drivers/gpu/drm/xe/xe_gt_idle.h | 1 + drivers/gpu/drm/xe/xe_gt_idle_types.h | 3 +++ 3 files changed, 24 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/xe/xe_gt_idle.c b/drivers/gpu/drm/xe/xe_gt_idle.c index ffd3ba7f66561..fbbace7b0b12a 100644 --- a/drivers/gpu/drm/xe/xe_gt_idle.c +++ b/drivers/gpu/drm/xe/xe_gt_idle.c @@ -69,6 +69,8 @@ static u64 get_residency_ms(struct xe_gt_idle *gtidle, u64 cur_residency) { u64 delta, overflow_residency, prev_residency; + lockdep_assert_held(>idle->lock); + overflow_residency = BIT_ULL(32); /* @@ -275,8 +277,21 @@ static ssize_t idle_status_show(struct device *dev, return sysfs_emit(buff, "%s\n", gt_idle_state_to_string(state)); } -static DEVICE_ATTR_RO(idle_status); +u64 xe_gt_idle_residency_msec(struct xe_gt_idle *gtidle) +{ + struct xe_guc_pc *pc = gtidle_to_pc(gtidle); + u64 residency; + unsigned long flags; + + raw_spin_lock_irqsave(>idle->lock, flags); + residency = get_residency_ms(gtidle, gtidle->idle_residency(pc)); + raw_spin_unlock_irqrestore(>idle->lock, flags); + + return residency; +} + +static DEVICE_ATTR_RO(idle_status); static ssize_t idle_residency_ms_show(struct device *dev, struct device_attribute *attr, char *buff) { @@ -285,10 +300,10 @@ static ssize_t idle_residency_ms_show(struct device *dev, u64 residency; xe_pm_runtime_get(pc_to_xe(pc)); - residency = gtidle->idle_residency(pc); + residency = xe_gt_idle_residency_msec(gtidle); xe_pm_runtime_put(pc_to_xe(pc)); - return sysfs_emit(buff, "%llu\n", get_residency_ms(gtidle, residency)); + return sysfs_emit(buff, "%llu\n", residency); } static DEVICE_ATTR_RO(idle_residency_ms); @@ -331,6 +346,8 @@ int xe_gt_idle_init(struct xe_gt_idle *gtidle) if (!kobj) return -ENOMEM; + raw_spin_lock_init(>idle->lock); + if (xe_gt_is_media_type(gt)) { snprintf(gtidle->name, sizeof(gtidle->name), "gt%d-mc", gt->info.id); gtidle->idle_residency = xe_guc_pc_mc6_residency; diff --git a/drivers/gpu/drm/xe/xe_gt_idle.h b/drivers/gpu/drm/xe/xe_gt_idle.h index 4455a6501cb07..591a01e181bcc 100644 --- a/drivers/gpu/drm/xe/xe_gt_idle.h +++ b/drivers/gpu/drm/xe/xe_gt_idle.h @@ -17,5 +17,6 @@ void xe_gt_idle_disable_c6(struct xe_gt *gt); void xe_gt_idle_enable_pg(struct xe_gt *gt); void xe_gt_idle_disable_pg(struct xe_gt *gt); int xe_gt_idle_pg_print(struct xe_gt *gt, struct drm_printer *p); +u64 xe_gt_idle_residency_msec(struct xe_gt_idle *gtidle); #endif /* _XE_GT_IDLE_H_ */ diff --git a/drivers/gpu/drm/xe/xe_gt_idle_types.h b/drivers/gpu/drm/xe/xe_gt_idle_types.h index b8b297a3f8848..a3667c567f8a7 100644 --- a/drivers/gpu/drm/xe/xe_gt_idle_types.h +++ b/drivers/gpu/drm/xe/xe_gt_idle_types.h @@ -6,6 +6,7 @@ #ifndef _XE_GT_IDLE_SYSFS_TYPES_H_ #define _XE_GT_IDLE_SYSFS_TYPES_H_ +#include #include struct xe_guc_pc; @@ -31,6 +32,8 @@ struct xe_gt_idle { u64 cur_residency; /** @prev_residency: previous residency counter */ u64 prev_residency; + /** @lock: Lock protecting idle residency counters */ + raw_spinlock_t lock; /** @idle_status: get the current idle state */ enum xe_gt_idle_state (*idle_status)(struct xe_guc_pc *pc); /** @idle_residency: get idle residency counter */ -- 2.39.5