- Linux-stable-mirror - lists.linaro.org

[Linux-stable-mirror] [PATCH] drm/i915/breadcrumbs: Ignore unsubmitted signalers

by Chris Wilson

When a request is preempted, it is unsubmitted from the HW queue and removed from the active list of breadcrumbs. In the process, this however triggers the signaler and it may see the clear rbtree with the old, and still valid, seqno. This confuses the signaler into action and signaling the fence. Fixes: d6a2289d9d6b ("drm/i915: Remove the preempted request from the execution queue") Signed-off-by: Chris Wilson <chris(a)chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin(a)linux.intel.com> Cc: Joonas Lahtinen <joonas.lahtinen(a)linux.intel.com> Cc: <stable(a)vger.kernel.org> # v4.12+ --- drivers/gpu/drm/i915/intel_breadcrumbs.c | 20 ++++---------------- 1 file changed, 4 insertions(+), 16 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_breadcrumbs.c b/drivers/gpu/drm/i915/intel_breadcrumbs.c index efbc627a2a25..b955f7d7bd0f 100644 --- a/drivers/gpu/drm/i915/intel_breadcrumbs.c +++ b/drivers/gpu/drm/i915/intel_breadcrumbs.c @@ -588,29 +588,16 @@ void intel_engine_remove_wait(struct intel_engine_cs *engine, spin_unlock_irq(&b->rb_lock); } -static bool signal_valid(const struct drm_i915_gem_request *request) -{ - return intel_wait_check_request(&request->signaling.wait, request); -} - static bool signal_complete(const struct drm_i915_gem_request *request) { if (!request) return false; - /* If another process served as the bottom-half it may have already - * signalled that this wait is already completed. - */ - if (intel_wait_complete(&request->signaling.wait)) - return signal_valid(request); - - /* Carefully check if the request is complete, giving time for the + /* + * Carefully check if the request is complete, giving time for the * seqno to be visible or if the GPU hung. */ - if (__i915_request_irq_complete(request)) - return true; - - return false; + return __i915_request_irq_complete(request); } static struct drm_i915_gem_request *to_signaler(struct rb_node *rb) @@ -712,6 +699,7 @@ static int intel_breadcrumbs_signaler(void *arg) &request->fence.flags)) { local_bh_disable(); dma_fence_signal(&request->fence); + GEM_BUG_ON(!i915_gem_request_completed(request)); local_bh_enable(); /* kick start the tasklets */ } -- 2.15.1

7 years, 9 months

2
5
0 0

[Linux-stable-mirror] [PATCH 3.18] ARM: exynos_defconfig: enable CONFIG_ROOT_NFS and dependencies

by Guillaume Tucker

Enable CONFIG_ROOT_NFS and dependencies (CONFIG_NFS_*, CONFIG_IP_PNP) in order to be able to boot the Exynos devices with NFS root. Tested on exynos4412-odroidx2. Signed-off-by: Guillaume Tucker <guillaume.tucker(a)collabora.com> --- arch/arm/configs/exynos_defconfig | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/arm/configs/exynos_defconfig b/arch/arm/configs/exynos_defconfig index e21ef830a483..999ea477be54 100644 --- a/arch/arm/configs/exynos_defconfig +++ b/arch/arm/configs/exynos_defconfig @@ -33,6 +33,10 @@ CONFIG_PACKET=y CONFIG_UNIX=y CONFIG_NET_KEY=y CONFIG_INET=y +CONFIG_IP_PNP=y +CONFIG_IP_PNP_DHCP=y +CONFIG_IP_PNP_BOOTP=y +CONFIG_IP_PNP_RARP=y CONFIG_RFKILL_REGULATOR=y CONFIG_UEVENT_HELPER_PATH="/sbin/hotplug" CONFIG_DEVTMPFS=y @@ -170,6 +174,10 @@ CONFIG_TMPFS=y CONFIG_TMPFS_POSIX_ACL=y CONFIG_CRAMFS=y CONFIG_ROMFS_FS=y +CONFIG_NFS_FS=y +CONFIG_NFS_V3_ACL=y +CONFIG_NFS_V4=y +CONFIG_ROOT_NFS=y CONFIG_NLS_CODEPAGE_437=y CONFIG_NLS_ASCII=y CONFIG_NLS_ISO8859_1=y -- 2.11.0

7 years, 9 months

2
5
0 0

[Linux-stable-mirror] [PATCH] ALSA: hda - Fix headset mic detection problem for two Dell machines

by Hui Wang

One of them has the codec of alc256 and the other one has the codec of alc289. Cc: <stable(a)vger.kernel.org> Signed-off-by: Hui Wang <hui.wang(a)canonical.com> --- sound/pci/hda/patch_realtek.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/sound/pci/hda/patch_realtek.c b/sound/pci/hda/patch_realtek.c index 2347588..b791efe 100644 --- a/sound/pci/hda/patch_realtek.c +++ b/sound/pci/hda/patch_realtek.c @@ -6735,6 +6735,11 @@ static const struct snd_hda_pin_quirk alc269_pin_fixup_tbl[] = { {0x14, 0x90170110}, {0x21, 0x02211020}), SND_HDA_PIN_QUIRK(0x10ec0256, 0x1028, "Dell", ALC255_FIXUP_DELL1_MIC_NO_PRESENCE, + {0x12, 0x90a60130}, + {0x14, 0x90170110}, + {0x14, 0x01011020}, + {0x21, 0x0221101f}), + SND_HDA_PIN_QUIRK(0x10ec0256, 0x1028, "Dell", ALC255_FIXUP_DELL1_MIC_NO_PRESENCE, ALC256_STANDARD_PINS), SND_HDA_PIN_QUIRK(0x10ec0256, 0x1043, "ASUS", ALC256_FIXUP_ASUS_MIC, {0x14, 0x90170110}, @@ -6803,6 +6808,10 @@ static const struct snd_hda_pin_quirk alc269_pin_fixup_tbl[] = { {0x12, 0x90a60120}, {0x14, 0x90170110}, {0x21, 0x0321101f}), + SND_HDA_PIN_QUIRK(0x10ec0289, 0x1028, "Dell", ALC225_FIXUP_DELL1_MIC_NO_PRESENCE, + {0x12, 0xb7a60130}, + {0x14, 0x90170110}, + {0x21, 0x04211020}), SND_HDA_PIN_QUIRK(0x10ec0290, 0x103c, "HP", ALC269_FIXUP_HP_MUTE_LED_MIC1, ALC290_STANDARD_PINS, {0x15, 0x04211040}, -- 2.7.4

7 years, 9 months

2
1
0 0

[Linux-stable-mirror] [PATCH 4.4.y 1/2] drm: rcar-du: Use the VBK interrupt for vblank events

by Nhan Nguyen

From: Laurent Pinchart <laurent.pinchart+renesas(a)ideasonboard.com> commit cbbb90b0c084d7dfb2ed8e3fecf8df200fbdd2a0 upstream. When implementing support for interlaced modes, the driver switched from reporting vblank events on the vertical blanking (VBK) interrupt to the frame end interrupt (FRM). This incorrectly divided the reported refresh rate by two. Fix it by moving back to the VBK interrupt. Fixes: 906eff7fcada ("drm: rcar-du: Implement support for interlaced modes") Cc: stable(a)vger.kernel.org Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas(a)ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham+renesas(a)ideasonboard.com> Signed-off-by: thongsyho <thong.ho.px(a)rvc.renesas.com> Signed-off-by: Nhan Nguyen <nhan.nguyen.yb(a)renesas.com> --- drivers/gpu/drm/rcar-du/rcar_du_crtc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c index 9befd62..25bdab6 100644 --- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c +++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c @@ -531,7 +531,7 @@ static irqreturn_t rcar_du_crtc_irq(int irq, void *arg) status = rcar_du_crtc_read(rcrtc, DSSR); rcar_du_crtc_write(rcrtc, DSRCR, status & DSRCR_MASK); - if (status & DSSR_FRM) { + if (status & DSSR_VBK) { drm_handle_vblank(rcrtc->crtc.dev, rcrtc->index); rcar_du_crtc_finish_page_flip(rcrtc); ret = IRQ_HANDLED; -- 1.9.1

7 years, 9 months

3
3
0 0

[Linux-stable-mirror] [PATCH 4.9.y 2/2] drm: rcar-du: Fix race condition when disabling planes at CRTC stop

by Nhan Nguyen

From: Laurent Pinchart <laurent.pinchart+renesas(a)ideasonboard.com> commit 641307df71fe77d7b38a477067495ede05d47295 upstream. When stopping the CRTC the driver must disable all planes and wait for the change to take effect at the next vblank. Merely calling drm_crtc_wait_one_vblank() is not enough, as the function doesn't include any mechanism to handle the race with vblank interrupts. Replace the drm_crtc_wait_one_vblank() call with a manual mechanism that handles the vblank interrupt race. Cc: stable(a)vger.kernel.org Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas(a)ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham+renesas(a)ideasonboard.com> Signed-off-by: thongsyho <thong.ho.px(a)rvc.renesas.com> Signed-off-by: Nhan Nguyen <nhan.nguyen.yb(a)renesas.com> --- drivers/gpu/drm/rcar-du/rcar_du_crtc.c | 53 ++++++++++++++++++++++++++++++---- drivers/gpu/drm/rcar-du/rcar_du_crtc.h | 8 +++++ 2 files changed, 55 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c index 848f7f2..3322b15 100644 --- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c +++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c @@ -392,6 +392,31 @@ static void rcar_du_crtc_start(struct rcar_du_crtc *rcrtc) rcrtc->started = true; } +static void rcar_du_crtc_disable_planes(struct rcar_du_crtc *rcrtc) +{ + struct rcar_du_device *rcdu = rcrtc->group->dev; + struct drm_crtc *crtc = &rcrtc->crtc; + u32 status; + /* Make sure vblank interrupts are enabled. */ + drm_crtc_vblank_get(crtc); + /* + * Disable planes and calculate how many vertical blanking interrupts we + * have to wait for. If a vertical blanking interrupt has been triggered + * but not processed yet, we don't know whether it occurred before or + * after the planes got disabled. We thus have to wait for two vblank + * interrupts in that case. + */ + spin_lock_irq(&rcrtc->vblank_lock); + rcar_du_group_write(rcrtc->group, rcrtc->index % 2 ? DS2PR : DS1PR, 0); + status = rcar_du_crtc_read(rcrtc, DSSR); + rcrtc->vblank_count = status & DSSR_VBK ? 2 : 1; + spin_unlock_irq(&rcrtc->vblank_lock); + if (!wait_event_timeout(rcrtc->vblank_wait, rcrtc->vblank_count == 0, + msecs_to_jiffies(100))) + dev_warn(rcdu->dev, "vertical blanking timeout\n"); + drm_crtc_vblank_put(crtc); +} + static void rcar_du_crtc_stop(struct rcar_du_crtc *rcrtc) { struct drm_crtc *crtc = &rcrtc->crtc; @@ -400,17 +425,16 @@ static void rcar_du_crtc_stop(struct rcar_du_crtc *rcrtc) return; /* Disable all planes and wait for the change to take effect. This is - * required as the DSnPR registers are updated on vblank, and no vblank - * will occur once the CRTC is stopped. Disabling planes when starting - * the CRTC thus wouldn't be enough as it would start scanning out - * immediately from old frame buffers until the next vblank. + * required as the plane enable registers are updated on vblank, and no + * vblank will occur once the CRTC is stopped. Disabling planes when + * starting the CRTC thus wouldn't be enough as it would start scanning + * out immediately from old frame buffers until the next vblank. * * This increases the CRTC stop delay, especially when multiple CRTCs * are stopped in one operation as we now wait for one vblank per CRTC. * Whether this can be improved needs to be researched. */ - rcar_du_group_write(rcrtc->group, rcrtc->index % 2 ? DS2PR : DS1PR, 0); - drm_crtc_wait_one_vblank(crtc); + rcar_du_crtc_disable_planes(rcrtc); /* Disable vertical blanking interrupt reporting. We first need to wait * for page flip completion before stopping the CRTC as userspace @@ -548,10 +572,25 @@ static irqreturn_t rcar_du_crtc_irq(int irq, void *arg) irqreturn_t ret = IRQ_NONE; u32 status; + spin_lock(&rcrtc->vblank_lock); + status = rcar_du_crtc_read(rcrtc, DSSR); rcar_du_crtc_write(rcrtc, DSRCR, status & DSRCR_MASK); if (status & DSSR_VBK) { + /* + * Wake up the vblank wait if the counter reaches 0. This must + * be protected by the vblank_lock to avoid races in + * rcar_du_crtc_disable_planes(). + */ + if (rcrtc->vblank_count) { + if (--rcrtc->vblank_count == 0) + wake_up(&rcrtc->vblank_wait); + } + } + spin_unlock(&rcrtc->vblank_lock); + + if (status & DSSR_VBK) { drm_crtc_handle_vblank(&rcrtc->crtc); rcar_du_crtc_finish_page_flip(rcrtc); ret = IRQ_HANDLED; @@ -606,6 +645,8 @@ int rcar_du_crtc_create(struct rcar_du_group *rgrp, unsigned int index) } init_waitqueue_head(&rcrtc->flip_wait); + init_waitqueue_head(&rcrtc->vblank_wait); + spin_lock_init(&rcrtc->vblank_lock); rcrtc->group = rgrp; rcrtc->mmio_offset = mmio_offsets[index]; diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.h b/drivers/gpu/drm/rcar-du/rcar_du_crtc.h index 6f08b7e..48bef05 100644 --- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.h +++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.h @@ -15,6 +15,7 @@ #define __RCAR_DU_CRTC_H__ #include <linux/mutex.h> +#include <linux/spinlock.h> #include <linux/wait.h> #include <drm/drmP.h> @@ -33,6 +34,9 @@ * @started: whether the CRTC has been started and is running * @event: event to post when the pending page flip completes * @flip_wait: wait queue used to signal page flip completion + * @vblank_lock: protects vblank_wait and vblank_count + * @vblank_wait: wait queue used to signal vertical blanking + * @vblank_count: number of vertical blanking interrupts to wait for * @outputs: bitmask of the outputs (enum rcar_du_output) driven by this CRTC * @group: CRTC group this CRTC belongs to */ @@ -48,6 +52,10 @@ struct rcar_du_crtc { struct drm_pending_vblank_event *event; wait_queue_head_t flip_wait; + spinlock_t vblank_lock; + wait_queue_head_t vblank_wait; + unsigned int vblank_count; + unsigned int outputs; struct rcar_du_group *group; -- 1.9.1

7 years, 9 months

1
0
0 0

[Linux-stable-mirror] [PATCH 4.9.y 1/2] drm: rcar-du: Use the VBK interrupt for vblank events

by Nhan Nguyen

From: Laurent Pinchart <laurent.pinchart+renesas(a)ideasonboard.com> commit cbbb90b0c084d7dfb2ed8e3fecf8df200fbdd2a0 upstream. When implementing support for interlaced modes, the driver switched from reporting vblank events on the vertical blanking (VBK) interrupt to the frame end interrupt (FRM). This incorrectly divided the reported refresh rate by two. Fix it by moving back to the VBK interrupt. Fixes: 906eff7fcada ("drm: rcar-du: Implement support for interlaced modes") Cc: stable(a)vger.kernel.org Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas(a)ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham+renesas(a)ideasonboard.com> Signed-off-by: thongsyho <thong.ho.px(a)rvc.renesas.com> Signed-off-by: Nhan Nguyen <nhan.nguyen.yb(a)renesas.com> --- drivers/gpu/drm/rcar-du/rcar_du_crtc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c index a2ec6d8..848f7f2 100644 --- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c +++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c @@ -551,7 +551,7 @@ static irqreturn_t rcar_du_crtc_irq(int irq, void *arg) status = rcar_du_crtc_read(rcrtc, DSSR); rcar_du_crtc_write(rcrtc, DSRCR, status & DSRCR_MASK); - if (status & DSSR_FRM) { + if (status & DSSR_VBK) { drm_crtc_handle_vblank(&rcrtc->crtc); rcar_du_crtc_finish_page_flip(rcrtc); ret = IRQ_HANDLED; -- 1.9.1

7 years, 9 months

1
0
0 0

[Linux-stable-mirror] [PATCH 4.9.y 3/3] ASoC: rsnd: avoid duplicate free_irq()

by Nhan Nguyen

From: Kuninori Morimoto <kuninori.morimoto.gx(a)renesas.com> commit e0936c3471a8411a5df327641fa3ffe12a2fb07b upstream. commit 1f8754d4daea5f ("ASoC: rsnd: don't call free_irq() on Parent SSI") fixed Parent SSI duplicate free_irq(). But on Renesas Sound, not only Parent SSI but also Multi SSI have same issue. This patch avoid duplicate free_irq() if it was not pure SSI. Fixes: 1f8754d4daea5f ("ASoC: rsnd: don't call free_irq() on Parent SSI") Cc: stable(a)vger.kernel.org Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx(a)renesas.com> Signed-off-by: Mark Brown <broonie(a)kernel.org> Signed-off-by: thongsyho <thong.ho.px(a)rvc.renesas.com> Signed-off-by: Nhan Nguyen <nhan.nguyen.yb(a)renesas.com> --- sound/soc/sh/rcar/ssi.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/sound/soc/sh/rcar/ssi.c b/sound/soc/sh/rcar/ssi.c index 9472d99..3454cba 100644 --- a/sound/soc/sh/rcar/ssi.c +++ b/sound/soc/sh/rcar/ssi.c @@ -694,12 +694,12 @@ static int rsnd_ssi_dma_remove(struct rsnd_mod *mod, struct rsnd_priv *priv) { struct rsnd_ssi *ssi = rsnd_mod_to_ssi(mod); - struct rsnd_mod *ssi_parent_mod = rsnd_io_to_mod_ssip(io); + struct rsnd_mod *pure_ssi_mod = rsnd_io_to_mod_ssi(io); struct device *dev = rsnd_priv_to_dev(priv); int irq = ssi->irq; - /* Do nothing for SSI parent mod */ - if (ssi_parent_mod == mod) + /* Do nothing if non SSI (= SSI parent, multi SSI) mod */ + if (pure_ssi_mod != mod) return 0; /* PIO will request IRQ again */ -- 1.9.1

7 years, 9 months

1
0
0 0

[Linux-stable-mirror] [PATCH 4.9.y 2/3] ASoC: rsnd: don't call free_irq() on Parent SSI

by Nhan Nguyen

From: Kuninori Morimoto <kuninori.morimoto.gx(a)renesas.com> commit 1f8754d4daea5f257370a52a30fcb22798c54516 upstream. If SSI uses shared pin, some SSI will be used as parent SSI. Then, normal SSI's remove and Parent SSI's remove (these are same SSI) will be called when unbind or remove timing. In this case, free_irq() will be called twice. This patch solve this issue. Cc: stable(a)vger.kernel.org Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx(a)renesas.com> Tested-by: Hiroyuki Yokoyama <hiroyuki.yokoyama.vx(a)renesas.com> Reported-by: Hiroyuki Yokoyama <hiroyuki.yokoyama.vx(a)renesas.com> Signed-off-by: Mark Brown <broonie(a)kernel.org> Signed-off-by: thongsyho <thong.ho.px(a)rvc.renesas.com> Signed-off-by: Nhan Nguyen <nhan.nguyen.yb(a)renesas.com> --- sound/soc/sh/rcar/ssi.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/sound/soc/sh/rcar/ssi.c b/sound/soc/sh/rcar/ssi.c index 6cb6db0..9472d99 100644 --- a/sound/soc/sh/rcar/ssi.c +++ b/sound/soc/sh/rcar/ssi.c @@ -694,9 +694,14 @@ static int rsnd_ssi_dma_remove(struct rsnd_mod *mod, struct rsnd_priv *priv) { struct rsnd_ssi *ssi = rsnd_mod_to_ssi(mod); + struct rsnd_mod *ssi_parent_mod = rsnd_io_to_mod_ssip(io); struct device *dev = rsnd_priv_to_dev(priv); int irq = ssi->irq; + /* Do nothing for SSI parent mod */ + if (ssi_parent_mod == mod) + return 0; + /* PIO will request IRQ again */ devm_free_irq(dev, irq, mod); -- 1.9.1

7 years, 9 months

1
0
0 0

[Linux-stable-mirror] [PATCH 4.9.y 1/3] ASoC: simple-card: Fix misleading error message

by Nhan Nguyen

From: Julian Scheel <julian(a)jusst.de> commit 7ac45d1635a4cd2e99a4b11903d4a2815ca1b27b upstream. In case cpu could not be found the error message would always refer to /codec/ not being found in DT. Fix this by catching the cpu node not found case explicitly. Cc: stable(a)vger.kernel.org Signed-off-by: Julian Scheel <julian(a)jusst.de> Signed-off-by: Mark Brown <broonie(a)kernel.org> Signed-off-by: thongsyho <thong.ho.px(a)rvc.renesas.com> Signed-off-by: Nhan Nguyen <nhan.nguyen.yb(a)renesas.com> --- sound/soc/generic/simple-card.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/sound/soc/generic/simple-card.c b/sound/soc/generic/simple-card.c index f608f8d2..dd88c2c 100644 --- a/sound/soc/generic/simple-card.c +++ b/sound/soc/generic/simple-card.c @@ -232,13 +232,19 @@ static int asoc_simple_card_dai_link_of(struct device_node *node, snprintf(prop, sizeof(prop), "%scpu", prefix); cpu = of_get_child_by_name(node, prop); + if (!cpu) { + ret = -EINVAL; + dev_err(dev, "%s: Can't find %s DT node\n", __func__, prop); + goto dai_link_of_err; + } + snprintf(prop, sizeof(prop), "%splat", prefix); plat = of_get_child_by_name(node, prop); snprintf(prop, sizeof(prop), "%scodec", prefix); codec = of_get_child_by_name(node, prop); - if (!cpu || !codec) { + if (!codec) { ret = -EINVAL; dev_err(dev, "%s: Can't find %s DT node\n", __func__, prop); goto dai_link_of_err; -- 1.9.1

7 years, 9 months

1
0
0 0

Re: [Linux-stable-mirror] [tip:sched/urgent] sched/rt: Up the root domain ref count when passing it around via IPIs

by Steven Rostedt

I see this was just applied to Linus's tree. This too probably should be tagged for stable as well. -- Steve On Tue, 6 Feb 2018 03:54:42 -0800 "tip-bot for Steven Rostedt (VMware)" <tipbot(a)zytor.com> wrote: > Commit-ID: 364f56653708ba8bcdefd4f0da2a42904baa8eeb > Gitweb: https://git.kernel.org/tip/364f56653708ba8bcdefd4f0da2a42904baa8eeb > Author: Steven Rostedt (VMware) <rostedt(a)goodmis.org> > AuthorDate: Tue, 23 Jan 2018 20:45:38 -0500 > Committer: Ingo Molnar <mingo(a)kernel.org> > CommitDate: Tue, 6 Feb 2018 10:20:33 +0100 > > sched/rt: Up the root domain ref count when passing it around via IPIs > > When issuing an IPI RT push, where an IPI is sent to each CPU that has more > than one RT task scheduled on it, it references the root domain's rto_mask, > that contains all the CPUs within the root domain that has more than one RT > task in the runable state. The problem is, after the IPIs are initiated, the > rq->lock is released. This means that the root domain that is associated to > the run queue could be freed while the IPIs are going around. > > Add a sched_get_rd() and a sched_put_rd() that will increment and decrement > the root domain's ref count respectively. This way when initiating the IPIs, > the scheduler will up the root domain's ref count before releasing the > rq->lock, ensuring that the root domain does not go away until the IPI round > is complete. > > Reported-by: Pavan Kondeti <pkondeti(a)codeaurora.org> > Signed-off-by: Steven Rostedt (VMware) <rostedt(a)goodmis.org> > Signed-off-by: Peter Zijlstra (Intel) <peterz(a)infradead.org> > Cc: Andrew Morton <akpm(a)linux-foundation.org> > Cc: Linus Torvalds <torvalds(a)linux-foundation.org> > Cc: Mike Galbraith <efault(a)gmx.de> > Cc: Peter Zijlstra <peterz(a)infradead.org> > Cc: Thomas Gleixner <tglx(a)linutronix.de> > Fixes: 4bdced5c9a292 ("sched/rt: Simplify the IPI based RT balancing logic") > Link: http://lkml.kernel.org/r/CAEU1=PkiHO35Dzna8EQqNSKW1fr1y1zRQ5y66X117MG06sQtN… > Signed-off-by: Ingo Molnar <mingo(a)kernel.org> > --- > kernel/sched/rt.c | 9 +++++++-- > kernel/sched/sched.h | 2 ++ > kernel/sched/topology.c | 13 +++++++++++++ > 3 files changed, 22 insertions(+), 2 deletions(-) > > diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c > index 2fb627d..89a086e 100644 > --- a/kernel/sched/rt.c > +++ b/kernel/sched/rt.c > @@ -1990,8 +1990,11 @@ static void tell_cpu_to_push(struct rq *rq) > > rto_start_unlock(&rq->rd->rto_loop_start); > > - if (cpu >= 0) > + if (cpu >= 0) { > + /* Make sure the rd does not get freed while pushing */ > + sched_get_rd(rq->rd); > irq_work_queue_on(&rq->rd->rto_push_work, cpu); > + } > } > > /* Called from hardirq context */ > @@ -2021,8 +2024,10 @@ void rto_push_irq_work_func(struct irq_work *work) > > raw_spin_unlock(&rd->rto_lock); > > - if (cpu < 0) > + if (cpu < 0) { > + sched_put_rd(rd); > return; > + } > > /* Try the next RT overloaded CPU */ > irq_work_queue_on(&rd->rto_push_work, cpu); > diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h > index 2e95505..fb5fc45 100644 > --- a/kernel/sched/sched.h > +++ b/kernel/sched/sched.h > @@ -691,6 +691,8 @@ extern struct mutex sched_domains_mutex; > extern void init_defrootdomain(void); > extern int sched_init_domains(const struct cpumask *cpu_map); > extern void rq_attach_root(struct rq *rq, struct root_domain *rd); > +extern void sched_get_rd(struct root_domain *rd); > +extern void sched_put_rd(struct root_domain *rd); > > #ifdef HAVE_RT_PUSH_IPI > extern void rto_push_irq_work_func(struct irq_work *work); > diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c > index 034cbed..519b024 100644 > --- a/kernel/sched/topology.c > +++ b/kernel/sched/topology.c > @@ -259,6 +259,19 @@ void rq_attach_root(struct rq *rq, struct root_domain *rd) > call_rcu_sched(&old_rd->rcu, free_rootdomain); > } > > +void sched_get_rd(struct root_domain *rd) > +{ > + atomic_inc(&rd->refcount); > +} > + > +void sched_put_rd(struct root_domain *rd) > +{ > + if (!atomic_dec_and_test(&rd->refcount)) > + return; > + > + call_rcu_sched(&rd->rcu, free_rootdomain); > +} > + > static int init_rootdomain(struct root_domain *rd) > { > if (!zalloc_cpumask_var(&rd->span, GFP_KERNEL))

7 years, 9 months

1
0
0 0

2025

2024

2023

2022

2021

2020

2019

2018

2017

Linux-stable-mirror