| Message ID | 20241105112502.710427-2-avri.altman@wdc.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Untie the host lock entanglement - part 2 | expand |
A gentle ping. Thanks, Avri > -----Original Message----- > From: Avri Altman <avri.altman@wdc.com> > Sent: Tuesday, November 5, 2024 1:25 PM > To: Martin K . Petersen <martin.petersen@oracle.com> > Cc: linux-scsi@vger.kernel.org; linux-kernel@vger.kernel.org; Bart Van Assche > <bvanassche@acm.org>; Avri Altman <Avri.Altman@wdc.com> > Subject: [PATCH v3 1/2] scsi: ufs: core: Introduce a new clock_gating lock > > Introduce a new clock gating lock to serialize access to some of the clock gating > members instead of the host_lock. > > While at it, simplify the code with the guard() macro and co for automatic > cleanup of the new lock. There are some explicit > spin_lock_irqsave/spin_unlock_irqrestore snaking instances I left behind > because I couldn't make heads or tails of it. > > Additionally, move the trace_ufshcd_clk_gating() call from inside the region > protected by the lock as it doesn't needs protection. > > Signed-off-by: Avri Altman <avri.altman@wdc.com> > --- > drivers/ufs/core/ufshcd.c | 93 +++++++++++++++++---------------------- > include/ufs/ufshcd.h | 8 +++- > 2 files changed, 46 insertions(+), 55 deletions(-) > > diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c index > e338867bc96c..62c0e2323f50 100644 > --- a/drivers/ufs/core/ufshcd.c > +++ b/drivers/ufs/core/ufshcd.c > @@ -1811,19 +1811,17 @@ static void ufshcd_exit_clk_scaling(struct ufs_hba > *hba) static void ufshcd_ungate_work(struct work_struct *work) { > int ret; > - unsigned long flags; > struct ufs_hba *hba = container_of(work, struct ufs_hba, > clk_gating.ungate_work); > > cancel_delayed_work_sync(&hba->clk_gating.gate_work); > > - spin_lock_irqsave(hba->host->host_lock, flags); > - if (hba->clk_gating.state == CLKS_ON) { > - spin_unlock_irqrestore(hba->host->host_lock, flags); > - return; > + scoped_guard(spinlock_irqsave, &hba->clk_gating.lock) > + { > + if (hba->clk_gating.state == CLKS_ON) > + return; > } > > - spin_unlock_irqrestore(hba->host->host_lock, flags); > ufshcd_hba_vreg_set_hpm(hba); > ufshcd_setup_clocks(hba, true); > > @@ -1858,7 +1856,7 @@ void ufshcd_hold(struct ufs_hba *hba) > if (!ufshcd_is_clkgating_allowed(hba) || > !hba->clk_gating.is_initialized) > return; > - spin_lock_irqsave(hba->host->host_lock, flags); > + spin_lock_irqsave(&hba->clk_gating.lock, flags); > hba->clk_gating.active_reqs++; > > start: > @@ -1874,11 +1872,11 @@ void ufshcd_hold(struct ufs_hba *hba) > */ > if (ufshcd_can_hibern8_during_gating(hba) && > ufshcd_is_link_hibern8(hba)) { > - spin_unlock_irqrestore(hba->host->host_lock, flags); > + spin_unlock_irqrestore(&hba->clk_gating.lock, flags); > flush_result = flush_work(&hba- > >clk_gating.ungate_work); > if (hba->clk_gating.is_suspended && !flush_result) > return; > - spin_lock_irqsave(hba->host->host_lock, flags); > + spin_lock_irqsave(&hba->clk_gating.lock, flags); > goto start; > } > break; > @@ -1907,17 +1905,17 @@ void ufshcd_hold(struct ufs_hba *hba) > */ > fallthrough; > case REQ_CLKS_ON: > - spin_unlock_irqrestore(hba->host->host_lock, flags); > + spin_unlock_irqrestore(&hba->clk_gating.lock, flags); > flush_work(&hba->clk_gating.ungate_work); > /* Make sure state is CLKS_ON before returning */ > - spin_lock_irqsave(hba->host->host_lock, flags); > + spin_lock_irqsave(&hba->clk_gating.lock, flags); > goto start; > default: > dev_err(hba->dev, "%s: clk gating is in invalid state %d\n", > __func__, hba->clk_gating.state); > break; > } > - spin_unlock_irqrestore(hba->host->host_lock, flags); > + spin_unlock_irqrestore(&hba->clk_gating.lock, flags); > } > EXPORT_SYMBOL_GPL(ufshcd_hold); > > @@ -1925,29 +1923,28 @@ static void ufshcd_gate_work(struct work_struct > *work) { > struct ufs_hba *hba = container_of(work, struct ufs_hba, > clk_gating.gate_work.work); > - unsigned long flags; > int ret; > > - spin_lock_irqsave(hba->host->host_lock, flags); > - /* > - * In case you are here to cancel this work the gating state > - * would be marked as REQ_CLKS_ON. In this case save time by > - * skipping the gating work and exit after changing the clock > - * state to CLKS_ON. > - */ > - if (hba->clk_gating.is_suspended || > - (hba->clk_gating.state != REQ_CLKS_OFF)) { > - hba->clk_gating.state = CLKS_ON; > - trace_ufshcd_clk_gating(dev_name(hba->dev), > - hba->clk_gating.state); > - goto rel_lock; > + scoped_guard(spinlock_irqsave, &hba->clk_gating.lock) > + { > + /* > + * In case you are here to cancel this work the gating state > + * would be marked as REQ_CLKS_ON. In this case save time by > + * skipping the gating work and exit after changing the clock > + * state to CLKS_ON. > + */ > + if (hba->clk_gating.is_suspended || > + hba->clk_gating.state != REQ_CLKS_OFF) { > + hba->clk_gating.state = CLKS_ON; > + trace_ufshcd_clk_gating(dev_name(hba->dev), > + hba->clk_gating.state); > + return; > + } > + if (ufshcd_is_ufs_dev_busy(hba) || > + hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL) > + return; > } > > - if (ufshcd_is_ufs_dev_busy(hba) || hba->ufshcd_state != > UFSHCD_STATE_OPERATIONAL) > - goto rel_lock; > - > - spin_unlock_irqrestore(hba->host->host_lock, flags); > - > /* put the link into hibern8 mode before turning off clocks */ > if (ufshcd_can_hibern8_during_gating(hba)) { > ret = ufshcd_uic_hibern8_enter(hba); > @@ -1957,7 +1954,7 @@ static void ufshcd_gate_work(struct work_struct > *work) > __func__, ret); > trace_ufshcd_clk_gating(dev_name(hba->dev), > hba->clk_gating.state); > - goto out; > + return; > } > ufshcd_set_link_hibern8(hba); > } > @@ -1977,16 +1974,12 @@ static void ufshcd_gate_work(struct work_struct > *work) > * prevent from doing cancel work multiple times when there are > * new requests arriving before the current cancel work is done. > */ > - spin_lock_irqsave(hba->host->host_lock, flags); > + guard(spinlock_irqsave)(&hba->clk_gating.lock); > if (hba->clk_gating.state == REQ_CLKS_OFF) { > hba->clk_gating.state = CLKS_OFF; > trace_ufshcd_clk_gating(dev_name(hba->dev), > hba->clk_gating.state); > } > -rel_lock: > - spin_unlock_irqrestore(hba->host->host_lock, flags); > -out: > - return; > } > > /* host lock must be held before calling this variant */ @@ -2013,11 +2006,8 > @@ static void __ufshcd_release(struct ufs_hba *hba) > > void ufshcd_release(struct ufs_hba *hba) { > - unsigned long flags; > - > - spin_lock_irqsave(hba->host->host_lock, flags); > + guard(spinlock_irqsave)(&hba->clk_gating.lock); > __ufshcd_release(hba); > - spin_unlock_irqrestore(hba->host->host_lock, flags); > } > EXPORT_SYMBOL_GPL(ufshcd_release); > > @@ -2032,11 +2022,9 @@ static ssize_t ufshcd_clkgate_delay_show(struct > device *dev, void ufshcd_clkgate_delay_set(struct device *dev, unsigned long > value) { > struct ufs_hba *hba = dev_get_drvdata(dev); > - unsigned long flags; > > - spin_lock_irqsave(hba->host->host_lock, flags); > + guard(spinlock_irqsave)(&hba->clk_gating.lock); > hba->clk_gating.delay_ms = value; > - spin_unlock_irqrestore(hba->host->host_lock, flags); > } > EXPORT_SYMBOL_GPL(ufshcd_clkgate_delay_set); > > @@ -2064,7 +2052,6 @@ static ssize_t ufshcd_clkgate_enable_store(struct > device *dev, > struct device_attribute *attr, const char *buf, size_t count) { > struct ufs_hba *hba = dev_get_drvdata(dev); > - unsigned long flags; > u32 value; > > if (kstrtou32(buf, 0, &value)) > @@ -2072,9 +2059,10 @@ static ssize_t ufshcd_clkgate_enable_store(struct > device *dev, > > value = !!value; > > - spin_lock_irqsave(hba->host->host_lock, flags); > + guard(spinlock_irqsave)(&hba->clk_gating.lock); > + > if (value == hba->clk_gating.is_enabled) > - goto out; > + return count; > > if (value) > __ufshcd_release(hba); > @@ -2082,8 +2070,7 @@ static ssize_t ufshcd_clkgate_enable_store(struct > device *dev, > hba->clk_gating.active_reqs++; > > hba->clk_gating.is_enabled = value; > -out: > - spin_unlock_irqrestore(hba->host->host_lock, flags); > + > return count; > } > > @@ -2125,6 +2112,8 @@ static void ufshcd_init_clk_gating(struct ufs_hba > *hba) > INIT_DELAYED_WORK(&hba->clk_gating.gate_work, > ufshcd_gate_work); > INIT_WORK(&hba->clk_gating.ungate_work, ufshcd_ungate_work); > > + spin_lock_init(&hba->clk_gating.lock); > + > hba->clk_gating.clk_gating_workq = alloc_ordered_workqueue( > "ufs_clk_gating_%d", WQ_MEM_RECLAIM | WQ_HIGHPRI, > hba->host->host_no); > @@ -9112,7 +9101,6 @@ static int ufshcd_setup_clocks(struct ufs_hba *hba, > bool on) > int ret = 0; > struct ufs_clk_info *clki; > struct list_head *head = &hba->clk_list_head; > - unsigned long flags; > ktime_t start = ktime_get(); > bool clk_state_changed = false; > > @@ -9163,11 +9151,10 @@ static int ufshcd_setup_clocks(struct ufs_hba *hba, > bool on) > clk_disable_unprepare(clki->clk); > } > } else if (!ret && on) { > - spin_lock_irqsave(hba->host->host_lock, flags); > - hba->clk_gating.state = CLKS_ON; > + scoped_guard(spinlock_irqsave, &hba->clk_gating.lock) > + hba->clk_gating.state = CLKS_ON; > trace_ufshcd_clk_gating(dev_name(hba->dev), > hba->clk_gating.state); > - spin_unlock_irqrestore(hba->host->host_lock, flags); > } > > if (clk_state_changed) > diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h index > d7aca9e61684..8f9997b0dbf9 100644 > --- a/include/ufs/ufshcd.h > +++ b/include/ufs/ufshcd.h > @@ -403,6 +403,8 @@ enum clk_gating_state { > * delay_ms > * @ungate_work: worker to turn on clocks that will be used in case of > * interrupt context > + * @clk_gating_workq: workqueue for clock gating work. > + * @lock: serialize access to some struct ufs_clk_gating members > * @state: the current clocks state > * @delay_ms: gating delay in ms > * @is_suspended: clk gating is suspended when set to 1 which can be used > @@ -413,11 +415,14 @@ enum clk_gating_state { > * @is_initialized: Indicates whether clock gating is initialized or not > * @active_reqs: number of requests that are pending and should be waited for > * completion before gating clocks. > - * @clk_gating_workq: workqueue for clock gating work. > */ > struct ufs_clk_gating { > struct delayed_work gate_work; > struct work_struct ungate_work; > + struct workqueue_struct *clk_gating_workq; > + > + spinlock_t lock; > + > enum clk_gating_state state; > unsigned long delay_ms; > bool is_suspended; > @@ -426,7 +431,6 @@ struct ufs_clk_gating { > bool is_enabled; > bool is_initialized; > int active_reqs; > - struct workqueue_struct *clk_gating_workq; > }; > > /** > -- > 2.25.1
On Tue, 2024-11-05 at 13:25 +0200, Avri Altman wrote: > - spin_lock_irqsave(hba->host->host_lock, flags); > - /* > - * In case you are here to cancel this work the gating state > - * would be marked as REQ_CLKS_ON. In this case save time by > - * skipping the gating work and exit after changing the clock > - * state to CLKS_ON. > - */ > - if (hba->clk_gating.is_suspended || > - (hba->clk_gating.state != REQ_CLKS_OFF)) { > - hba->clk_gating.state = CLKS_ON; > - trace_ufshcd_clk_gating(dev_name(hba->dev), > - hba->clk_gating.state); > - goto rel_lock; > + scoped_guard(spinlock_irqsave, &hba->clk_gating.lock) > + { > + /* > + * In case you are here to cancel this work the > gating state > + * would be marked as REQ_CLKS_ON. In this case save > time by > + * skipping the gating work and exit after changing > the clock > + * state to CLKS_ON. > + */ > + if (hba->clk_gating.is_suspended || > + hba->clk_gating.state != REQ_CLKS_OFF) { > + hba->clk_gating.state = CLKS_ON; > + trace_ufshcd_clk_gating(dev_name(hba->dev), > + hba- > >clk_gating.state); > + return; > + } > + if (ufshcd_is_ufs_dev_busy(hba) || > + hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL) > + return; > } I'm wondering if it would be safe to replace host_lock with gating.lock or scaling.lock. For instance, in above context, ufshcd_state needs to be checked, but it's currently serialized by host_lock. King regards, Bean
> On Tue, 2024-11-05 at 13:25 +0200, Avri Altman wrote: > > - spin_lock_irqsave(hba->host->host_lock, flags); > > - /* > > - * In case you are here to cancel this work the gating state > > - * would be marked as REQ_CLKS_ON. In this case save time by > > - * skipping the gating work and exit after changing the clock > > - * state to CLKS_ON. > > - */ > > - if (hba->clk_gating.is_suspended || > > - (hba->clk_gating.state != REQ_CLKS_OFF)) { > > - hba->clk_gating.state = CLKS_ON; > > - trace_ufshcd_clk_gating(dev_name(hba->dev), > > - hba->clk_gating.state); > > - goto rel_lock; > > + scoped_guard(spinlock_irqsave, &hba->clk_gating.lock) > > + { > > + /* > > + * In case you are here to cancel this work the > > gating state > > + * would be marked as REQ_CLKS_ON. In this case save > > time by > > + * skipping the gating work and exit after changing > > the clock > > + * state to CLKS_ON. > > + */ > > + if (hba->clk_gating.is_suspended || > > + hba->clk_gating.state != REQ_CLKS_OFF) { > > + hba->clk_gating.state = CLKS_ON; > > + trace_ufshcd_clk_gating(dev_name(hba->dev), > > + hba- > > >clk_gating.state); > > + return; > > + } > > + if (ufshcd_is_ufs_dev_busy(hba) || > > + hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL) > > + return; > > } > > I'm wondering if it would be safe to replace host_lock with gating.lock or > scaling.lock. For instance, in above context, ufshcd_state needs to be checked, > but it's currently serialized by host_lock. Hi, thank you for your feedback. Yeah - I think you have a valid point. I will remove the state check out of the scope of the clk_gating.lock, and restore it under the host lock. Thanks, Avri > > King regards, > Bean
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c index e338867bc96c..62c0e2323f50 100644 --- a/drivers/ufs/core/ufshcd.c +++ b/drivers/ufs/core/ufshcd.c @@ -1811,19 +1811,17 @@ static void ufshcd_exit_clk_scaling(struct ufs_hba *hba) static void ufshcd_ungate_work(struct work_struct *work) { int ret; - unsigned long flags; struct ufs_hba *hba = container_of(work, struct ufs_hba, clk_gating.ungate_work); cancel_delayed_work_sync(&hba->clk_gating.gate_work); - spin_lock_irqsave(hba->host->host_lock, flags); - if (hba->clk_gating.state == CLKS_ON) { - spin_unlock_irqrestore(hba->host->host_lock, flags); - return; + scoped_guard(spinlock_irqsave, &hba->clk_gating.lock) + { + if (hba->clk_gating.state == CLKS_ON) + return; } - spin_unlock_irqrestore(hba->host->host_lock, flags); ufshcd_hba_vreg_set_hpm(hba); ufshcd_setup_clocks(hba, true); @@ -1858,7 +1856,7 @@ void ufshcd_hold(struct ufs_hba *hba) if (!ufshcd_is_clkgating_allowed(hba) || !hba->clk_gating.is_initialized) return; - spin_lock_irqsave(hba->host->host_lock, flags); + spin_lock_irqsave(&hba->clk_gating.lock, flags); hba->clk_gating.active_reqs++; start: @@ -1874,11 +1872,11 @@ void ufshcd_hold(struct ufs_hba *hba) */ if (ufshcd_can_hibern8_during_gating(hba) && ufshcd_is_link_hibern8(hba)) { - spin_unlock_irqrestore(hba->host->host_lock, flags); + spin_unlock_irqrestore(&hba->clk_gating.lock, flags); flush_result = flush_work(&hba->clk_gating.ungate_work); if (hba->clk_gating.is_suspended && !flush_result) return; - spin_lock_irqsave(hba->host->host_lock, flags); + spin_lock_irqsave(&hba->clk_gating.lock, flags); goto start; } break; @@ -1907,17 +1905,17 @@ void ufshcd_hold(struct ufs_hba *hba) */ fallthrough; case REQ_CLKS_ON: - spin_unlock_irqrestore(hba->host->host_lock, flags); + spin_unlock_irqrestore(&hba->clk_gating.lock, flags); flush_work(&hba->clk_gating.ungate_work); /* Make sure state is CLKS_ON before returning */ - spin_lock_irqsave(hba->host->host_lock, flags); + spin_lock_irqsave(&hba->clk_gating.lock, flags); goto start; default: dev_err(hba->dev, "%s: clk gating is in invalid state %d\n", __func__, hba->clk_gating.state); break; } - spin_unlock_irqrestore(hba->host->host_lock, flags); + spin_unlock_irqrestore(&hba->clk_gating.lock, flags); } EXPORT_SYMBOL_GPL(ufshcd_hold); @@ -1925,29 +1923,28 @@ static void ufshcd_gate_work(struct work_struct *work) { struct ufs_hba *hba = container_of(work, struct ufs_hba, clk_gating.gate_work.work); - unsigned long flags; int ret; - spin_lock_irqsave(hba->host->host_lock, flags); - /* - * In case you are here to cancel this work the gating state - * would be marked as REQ_CLKS_ON. In this case save time by - * skipping the gating work and exit after changing the clock - * state to CLKS_ON. - */ - if (hba->clk_gating.is_suspended || - (hba->clk_gating.state != REQ_CLKS_OFF)) { - hba->clk_gating.state = CLKS_ON; - trace_ufshcd_clk_gating(dev_name(hba->dev), - hba->clk_gating.state); - goto rel_lock; + scoped_guard(spinlock_irqsave, &hba->clk_gating.lock) + { + /* + * In case you are here to cancel this work the gating state + * would be marked as REQ_CLKS_ON. In this case save time by + * skipping the gating work and exit after changing the clock + * state to CLKS_ON. + */ + if (hba->clk_gating.is_suspended || + hba->clk_gating.state != REQ_CLKS_OFF) { + hba->clk_gating.state = CLKS_ON; + trace_ufshcd_clk_gating(dev_name(hba->dev), + hba->clk_gating.state); + return; + } + if (ufshcd_is_ufs_dev_busy(hba) || + hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL) + return; } - if (ufshcd_is_ufs_dev_busy(hba) || hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL) - goto rel_lock; - - spin_unlock_irqrestore(hba->host->host_lock, flags); - /* put the link into hibern8 mode before turning off clocks */ if (ufshcd_can_hibern8_during_gating(hba)) { ret = ufshcd_uic_hibern8_enter(hba); @@ -1957,7 +1954,7 @@ static void ufshcd_gate_work(struct work_struct *work) __func__, ret); trace_ufshcd_clk_gating(dev_name(hba->dev), hba->clk_gating.state); - goto out; + return; } ufshcd_set_link_hibern8(hba); } @@ -1977,16 +1974,12 @@ static void ufshcd_gate_work(struct work_struct *work) * prevent from doing cancel work multiple times when there are * new requests arriving before the current cancel work is done. */ - spin_lock_irqsave(hba->host->host_lock, flags); + guard(spinlock_irqsave)(&hba->clk_gating.lock); if (hba->clk_gating.state == REQ_CLKS_OFF) { hba->clk_gating.state = CLKS_OFF; trace_ufshcd_clk_gating(dev_name(hba->dev), hba->clk_gating.state); } -rel_lock: - spin_unlock_irqrestore(hba->host->host_lock, flags); -out: - return; } /* host lock must be held before calling this variant */ @@ -2013,11 +2006,8 @@ static void __ufshcd_release(struct ufs_hba *hba) void ufshcd_release(struct ufs_hba *hba) { - unsigned long flags; - - spin_lock_irqsave(hba->host->host_lock, flags); + guard(spinlock_irqsave)(&hba->clk_gating.lock); __ufshcd_release(hba); - spin_unlock_irqrestore(hba->host->host_lock, flags); } EXPORT_SYMBOL_GPL(ufshcd_release); @@ -2032,11 +2022,9 @@ static ssize_t ufshcd_clkgate_delay_show(struct device *dev, void ufshcd_clkgate_delay_set(struct device *dev, unsigned long value) { struct ufs_hba *hba = dev_get_drvdata(dev); - unsigned long flags; - spin_lock_irqsave(hba->host->host_lock, flags); + guard(spinlock_irqsave)(&hba->clk_gating.lock); hba->clk_gating.delay_ms = value; - spin_unlock_irqrestore(hba->host->host_lock, flags); } EXPORT_SYMBOL_GPL(ufshcd_clkgate_delay_set); @@ -2064,7 +2052,6 @@ static ssize_t ufshcd_clkgate_enable_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct ufs_hba *hba = dev_get_drvdata(dev); - unsigned long flags; u32 value; if (kstrtou32(buf, 0, &value)) @@ -2072,9 +2059,10 @@ static ssize_t ufshcd_clkgate_enable_store(struct device *dev, value = !!value; - spin_lock_irqsave(hba->host->host_lock, flags); + guard(spinlock_irqsave)(&hba->clk_gating.lock); + if (value == hba->clk_gating.is_enabled) - goto out; + return count; if (value) __ufshcd_release(hba); @@ -2082,8 +2070,7 @@ static ssize_t ufshcd_clkgate_enable_store(struct device *dev, hba->clk_gating.active_reqs++; hba->clk_gating.is_enabled = value; -out: - spin_unlock_irqrestore(hba->host->host_lock, flags); + return count; } @@ -2125,6 +2112,8 @@ static void ufshcd_init_clk_gating(struct ufs_hba *hba) INIT_DELAYED_WORK(&hba->clk_gating.gate_work, ufshcd_gate_work); INIT_WORK(&hba->clk_gating.ungate_work, ufshcd_ungate_work); + spin_lock_init(&hba->clk_gating.lock); + hba->clk_gating.clk_gating_workq = alloc_ordered_workqueue( "ufs_clk_gating_%d", WQ_MEM_RECLAIM | WQ_HIGHPRI, hba->host->host_no); @@ -9112,7 +9101,6 @@ static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on) int ret = 0; struct ufs_clk_info *clki; struct list_head *head = &hba->clk_list_head; - unsigned long flags; ktime_t start = ktime_get(); bool clk_state_changed = false; @@ -9163,11 +9151,10 @@ static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on) clk_disable_unprepare(clki->clk); } } else if (!ret && on) { - spin_lock_irqsave(hba->host->host_lock, flags); - hba->clk_gating.state = CLKS_ON; + scoped_guard(spinlock_irqsave, &hba->clk_gating.lock) + hba->clk_gating.state = CLKS_ON; trace_ufshcd_clk_gating(dev_name(hba->dev), hba->clk_gating.state); - spin_unlock_irqrestore(hba->host->host_lock, flags); } if (clk_state_changed) diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h index d7aca9e61684..8f9997b0dbf9 100644 --- a/include/ufs/ufshcd.h +++ b/include/ufs/ufshcd.h @@ -403,6 +403,8 @@ enum clk_gating_state { * delay_ms * @ungate_work: worker to turn on clocks that will be used in case of * interrupt context + * @clk_gating_workq: workqueue for clock gating work. + * @lock: serialize access to some struct ufs_clk_gating members * @state: the current clocks state * @delay_ms: gating delay in ms * @is_suspended: clk gating is suspended when set to 1 which can be used @@ -413,11 +415,14 @@ enum clk_gating_state { * @is_initialized: Indicates whether clock gating is initialized or not * @active_reqs: number of requests that are pending and should be waited for * completion before gating clocks. - * @clk_gating_workq: workqueue for clock gating work. */ struct ufs_clk_gating { struct delayed_work gate_work; struct work_struct ungate_work; + struct workqueue_struct *clk_gating_workq; + + spinlock_t lock; + enum clk_gating_state state; unsigned long delay_ms; bool is_suspended; @@ -426,7 +431,6 @@ struct ufs_clk_gating { bool is_enabled; bool is_initialized; int active_reqs; - struct workqueue_struct *clk_gating_workq; }; /**
Introduce a new clock gating lock to serialize access to some of the clock gating members instead of the host_lock. While at it, simplify the code with the guard() macro and co for automatic cleanup of the new lock. There are some explicit spin_lock_irqsave/spin_unlock_irqrestore snaking instances I left behind because I couldn't make heads or tails of it. Additionally, move the trace_ufshcd_clk_gating() call from inside the region protected by the lock as it doesn't needs protection. Signed-off-by: Avri Altman <avri.altman@wdc.com> --- drivers/ufs/core/ufshcd.c | 93 +++++++++++++++++---------------------- include/ufs/ufshcd.h | 8 +++- 2 files changed, 46 insertions(+), 55 deletions(-)