From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A3718C3ABB6 for ; Tue, 6 May 2025 01:58:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=GfWWBHP4TE4uEg1T6lSCPsQsLGjZBRlZyRRMeoLEjKg=; b=LIwmDRRJTSFM8B A8RigT1/BcKhhXhUheFxChP6MgKPoxpwd3iyh4tpflEyjVEloTXdsL5CBitXUF5MSzhKo1iN/iObG rYWFN7/12dJvQs7BysdKWatvlPRp/1Ls/4etFsUhe/qFb+JLfsJ13iK3g0FXc/cPZ0lDDpnSA0Y7k HCnIxmpJBnakZufYlabQMCpOr+1kbR1F6J6FIhTREV4gl3dcHZFVdE45kr7dxfskOQ0jNIfAyHeuM 9J75HhzIXTRjrYlDrmfYba2s5P3x0hveibiod25aLoLusFAZgISwbnooLrrUlMU24G2jS5kI8slRM 02CWOVnCpNwjtnxJ6VmA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uC7ZI-00000009dHh-1Jbf; Tue, 06 May 2025 01:58:00 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uC4cz-00000008sCM-1RbO for linux-riscv@lists.infradead.org; Mon, 05 May 2025 22:49:38 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 8AF8C5C5717; Mon, 5 May 2025 22:47:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 52B0BC4CEED; Mon, 5 May 2025 22:49:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1746485376; bh=IIXK9K2DVzIQoWl91FaWaC67MYNxQPN0H26Z8DZxsgg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ry+pjD6YMpviKAtn30mSSsQi2gJkZEZJcj5Q9SLYvUOXu+cG61VTho7HfliPj/SSP AtBg2jRgGIbs9EO2u+KH7aq8Hs8t/vdhyGZSYqDndDMrQzCAHz0wh4/4nnGtgncGJX CG13G4jMVj7as3lVReppNPpEsrVWOuQdXMhyIGYsLJHNvEOn1owvl3BGDYcmZvBoNg m3jfRg5YVamLzl8a9uqDRF/MdAimf/Mu+Mju4EiZd6AM80QFznZct4a9aYTAq4UjZ8 AVRl2lYMsRa1El2P7BtCTLVe7IF2t8Lxv9oTa5jUUcr0BDHSgprBEQlU4rz3n5wQ+N 4osKjEbvSQMTg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Anup Patel , Thomas Gleixner , Sasha Levin , anup@brainfault.org, paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, linux-riscv@lists.infradead.org Subject: [PATCH AUTOSEL 6.12 298/486] irqchip/riscv-imsic: Separate next and previous pointers in IMSIC vector Date: Mon, 5 May 2025 18:36:14 -0400 Message-Id: <20250505223922.2682012-298-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250505223922.2682012-1-sashal@kernel.org> References: <20250505223922.2682012-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.12.26 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250505_154937_474068_F63E1E7F X-CRM114-Status: GOOD ( 23.78 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: Anup Patel [ Upstream commit 0f67911e821c67ecfccc365a2103ce276a9a56fe ] Currently, there is only one "move" pointer in struct imsic_vector so during vector movement the old vector points to the new vector and new vector points to itself. To support forced cleanup of the old vector, add separate "move_next" and "move_prev" pointers to struct imsic_vector, where during vector movement the "move_next" pointer of the old vector points to the new vector and the "move_prev" pointer of the new vector points to the old vector. Both "move_next" and "move_prev" pointers are cleared separately by __imsic_local_sync() with a restriction that "move_prev" on the new CPU is cleared only after the old CPU has cleared "move_next". Signed-off-by: Anup Patel Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20250217085657.789309-8-apatel@ventanamicro.com Signed-off-by: Sasha Levin --- drivers/irqchip/irq-riscv-imsic-early.c | 8 ++- drivers/irqchip/irq-riscv-imsic-state.c | 96 +++++++++++++++++-------- drivers/irqchip/irq-riscv-imsic-state.h | 7 +- 3 files changed, 78 insertions(+), 33 deletions(-) diff --git a/drivers/irqchip/irq-riscv-imsic-early.c b/drivers/irqchip/irq-riscv-imsic-early.c index c5c2e6929a2f5..b5def6268936e 100644 --- a/drivers/irqchip/irq-riscv-imsic-early.c +++ b/drivers/irqchip/irq-riscv-imsic-early.c @@ -77,6 +77,12 @@ static void imsic_handle_irq(struct irq_desc *desc) struct imsic_vector *vec; unsigned long local_id; + /* + * Process pending local synchronization instead of waiting + * for per-CPU local timer to expire. + */ + imsic_local_sync_all(false); + chained_irq_enter(chip, desc); while ((local_id = csr_swap(CSR_TOPEI, 0))) { @@ -120,7 +126,7 @@ static int imsic_starting_cpu(unsigned int cpu) * Interrupts identities might have been enabled/disabled while * this CPU was not running so sync-up local enable/disable state. */ - imsic_local_sync_all(); + imsic_local_sync_all(true); /* Enable local interrupt delivery */ imsic_local_delivery(true); diff --git a/drivers/irqchip/irq-riscv-imsic-state.c b/drivers/irqchip/irq-riscv-imsic-state.c index b97e6cd89ed74..1aeba76d72795 100644 --- a/drivers/irqchip/irq-riscv-imsic-state.c +++ b/drivers/irqchip/irq-riscv-imsic-state.c @@ -124,10 +124,11 @@ void __imsic_eix_update(unsigned long base_id, unsigned long num_id, bool pend, } } -static void __imsic_local_sync(struct imsic_local_priv *lpriv) +static bool __imsic_local_sync(struct imsic_local_priv *lpriv) { struct imsic_local_config *mlocal; struct imsic_vector *vec, *mvec; + bool ret = true; int i; lockdep_assert_held(&lpriv->lock); @@ -143,35 +144,75 @@ static void __imsic_local_sync(struct imsic_local_priv *lpriv) __imsic_id_clear_enable(i); /* - * If the ID was being moved to a new ID on some other CPU - * then we can get a MSI during the movement so check the - * ID pending bit and re-trigger the new ID on other CPU - * using MMIO write. + * Clear the previous vector pointer of the new vector only + * after the movement is complete on the old CPU. */ - mvec = READ_ONCE(vec->move); - WRITE_ONCE(vec->move, NULL); - if (mvec && mvec != vec) { + mvec = READ_ONCE(vec->move_prev); + if (mvec) { + /* + * If the old vector has not been updated then + * try again in the next sync-up call. + */ + if (READ_ONCE(mvec->move_next)) { + ret = false; + continue; + } + + WRITE_ONCE(vec->move_prev, NULL); + } + + /* + * If a vector was being moved to a new vector on some other + * CPU then we can get a MSI during the movement so check the + * ID pending bit and re-trigger the new ID on other CPU using + * MMIO write. + */ + mvec = READ_ONCE(vec->move_next); + if (mvec) { if (__imsic_id_read_clear_pending(i)) { mlocal = per_cpu_ptr(imsic->global.local, mvec->cpu); writel_relaxed(mvec->local_id, mlocal->msi_va); } + WRITE_ONCE(vec->move_next, NULL); imsic_vector_free(&lpriv->vectors[i]); } skip: bitmap_clear(lpriv->dirty_bitmap, i, 1); } + + return ret; } -void imsic_local_sync_all(void) +#ifdef CONFIG_SMP +static void __imsic_local_timer_start(struct imsic_local_priv *lpriv) +{ + lockdep_assert_held(&lpriv->lock); + + if (!timer_pending(&lpriv->timer)) { + lpriv->timer.expires = jiffies + 1; + add_timer_on(&lpriv->timer, smp_processor_id()); + } +} +#else +static inline void __imsic_local_timer_start(struct imsic_local_priv *lpriv) +{ +} +#endif + +void imsic_local_sync_all(bool force_all) { struct imsic_local_priv *lpriv = this_cpu_ptr(imsic->lpriv); unsigned long flags; raw_spin_lock_irqsave(&lpriv->lock, flags); - bitmap_fill(lpriv->dirty_bitmap, imsic->global.nr_ids + 1); - __imsic_local_sync(lpriv); + + if (force_all) + bitmap_fill(lpriv->dirty_bitmap, imsic->global.nr_ids + 1); + if (!__imsic_local_sync(lpriv)) + __imsic_local_timer_start(lpriv); + raw_spin_unlock_irqrestore(&lpriv->lock, flags); } @@ -190,12 +231,7 @@ void imsic_local_delivery(bool enable) #ifdef CONFIG_SMP static void imsic_local_timer_callback(struct timer_list *timer) { - struct imsic_local_priv *lpriv = this_cpu_ptr(imsic->lpriv); - unsigned long flags; - - raw_spin_lock_irqsave(&lpriv->lock, flags); - __imsic_local_sync(lpriv); - raw_spin_unlock_irqrestore(&lpriv->lock, flags); + imsic_local_sync_all(false); } static void __imsic_remote_sync(struct imsic_local_priv *lpriv, unsigned int cpu) @@ -216,14 +252,11 @@ static void __imsic_remote_sync(struct imsic_local_priv *lpriv, unsigned int cpu */ if (cpu_online(cpu)) { if (cpu == smp_processor_id()) { - __imsic_local_sync(lpriv); - return; + if (__imsic_local_sync(lpriv)) + return; } - if (!timer_pending(&lpriv->timer)) { - lpriv->timer.expires = jiffies + 1; - add_timer_on(&lpriv->timer, cpu); - } + __imsic_local_timer_start(lpriv); } } #else @@ -278,8 +311,9 @@ void imsic_vector_unmask(struct imsic_vector *vec) raw_spin_unlock(&lpriv->lock); } -static bool imsic_vector_move_update(struct imsic_local_priv *lpriv, struct imsic_vector *vec, - bool new_enable, struct imsic_vector *new_move) +static bool imsic_vector_move_update(struct imsic_local_priv *lpriv, + struct imsic_vector *vec, bool is_old_vec, + bool new_enable, struct imsic_vector *move_vec) { unsigned long flags; bool enabled; @@ -289,7 +323,10 @@ static bool imsic_vector_move_update(struct imsic_local_priv *lpriv, struct imsi /* Update enable and move details */ enabled = READ_ONCE(vec->enable); WRITE_ONCE(vec->enable, new_enable); - WRITE_ONCE(vec->move, new_move); + if (is_old_vec) + WRITE_ONCE(vec->move_next, move_vec); + else + WRITE_ONCE(vec->move_prev, move_vec); /* Mark the vector as dirty and synchronize */ bitmap_set(lpriv->dirty_bitmap, vec->local_id, 1); @@ -322,8 +359,8 @@ void imsic_vector_move(struct imsic_vector *old_vec, struct imsic_vector *new_ve * interrupt on the old vector while device was being moved * to the new vector. */ - enabled = imsic_vector_move_update(old_lpriv, old_vec, false, new_vec); - imsic_vector_move_update(new_lpriv, new_vec, enabled, new_vec); + enabled = imsic_vector_move_update(old_lpriv, old_vec, true, false, new_vec); + imsic_vector_move_update(new_lpriv, new_vec, false, enabled, old_vec); } #ifdef CONFIG_GENERIC_IRQ_DEBUGFS @@ -386,7 +423,8 @@ struct imsic_vector *imsic_vector_alloc(unsigned int hwirq, const struct cpumask vec = &lpriv->vectors[local_id]; vec->hwirq = hwirq; vec->enable = false; - vec->move = NULL; + vec->move_next = NULL; + vec->move_prev = NULL; return vec; } diff --git a/drivers/irqchip/irq-riscv-imsic-state.h b/drivers/irqchip/irq-riscv-imsic-state.h index 391e442808275..f02842b84ed58 100644 --- a/drivers/irqchip/irq-riscv-imsic-state.h +++ b/drivers/irqchip/irq-riscv-imsic-state.h @@ -23,7 +23,8 @@ struct imsic_vector { unsigned int hwirq; /* Details accessed using local lock held */ bool enable; - struct imsic_vector *move; + struct imsic_vector *move_next; + struct imsic_vector *move_prev; }; struct imsic_local_priv { @@ -74,7 +75,7 @@ static inline void __imsic_id_clear_enable(unsigned long id) __imsic_eix_update(id, 1, false, false); } -void imsic_local_sync_all(void); +void imsic_local_sync_all(bool force_all); void imsic_local_delivery(bool enable); void imsic_vector_mask(struct imsic_vector *vec); @@ -87,7 +88,7 @@ static inline bool imsic_vector_isenabled(struct imsic_vector *vec) static inline struct imsic_vector *imsic_vector_get_move(struct imsic_vector *vec) { - return READ_ONCE(vec->move); + return READ_ONCE(vec->move_prev); } void imsic_vector_move(struct imsic_vector *old_vec, struct imsic_vector *new_vec); -- 2.39.5 _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv