| Message ID | 1380045916-29833-1-git-send-email-srinivas.pandruvada@linux.intel.com (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Delegated to: | Zhang Rui |
| Headers | show |
On Tue, 2013-09-24 at 11:05 -0700, Srinivas Pandruvada wrote: > x86_pkg_temp receives thermal notifications via a callback from a > therm_throt driver, where thermal interrupts are processed. > This callback is pkg_temp_thermal_platform_thermal_notify. Here to > avoid multiple interrupts from cores in a package, we disable the > source and also set a variable to avoid scheduling delayed work function. > This variable is protected via spin_lock_irqsave. On one buggy platform, > we still receiving interrupts even if the source is disabled. This > can cause deadlock/lockdep warning, when interrupt is generated while under > spinlock in work function. > Change spin_lock to spin_lock_irqsave and spin_unlock to > spin_unlock_irqrestore as the data it is trying to protect can also > be modified in a notification call called from interrupt handler. > > Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> applied to thermal .next. thanks, rui > --- > drivers/thermal/x86_pkg_temp_thermal.c | 14 ++++++++------ > 1 file changed, 8 insertions(+), 6 deletions(-) > > diff --git a/drivers/thermal/x86_pkg_temp_thermal.c b/drivers/thermal/x86_pkg_temp_thermal.c > index f36950e..7722cb9 100644 > --- a/drivers/thermal/x86_pkg_temp_thermal.c > +++ b/drivers/thermal/x86_pkg_temp_thermal.c > @@ -316,18 +316,19 @@ static void pkg_temp_thermal_threshold_work_fn(struct work_struct *work) > int phy_id = topology_physical_package_id(cpu); > struct phy_dev_entry *phdev = pkg_temp_thermal_get_phy_entry(cpu); > bool notify = false; > + unsigned long flags; > > if (!phdev) > return; > > - spin_lock(&pkg_work_lock); > + spin_lock_irqsave(&pkg_work_lock, flags); > ++pkg_work_cnt; > if (unlikely(phy_id > max_phy_id)) { > - spin_unlock(&pkg_work_lock); > + spin_unlock_irqrestore(&pkg_work_lock, flags); > return; > } > pkg_work_scheduled[phy_id] = 0; > - spin_unlock(&pkg_work_lock); > + spin_unlock_irqrestore(&pkg_work_lock, flags); > > enable_pkg_thres_interrupt(); > rdmsrl(MSR_IA32_PACKAGE_THERM_STATUS, msr_val); > @@ -397,6 +398,7 @@ static int pkg_temp_thermal_device_add(unsigned int cpu) > int thres_count; > u32 eax, ebx, ecx, edx; > u8 *temp; > + unsigned long flags; > > cpuid(6, &eax, &ebx, &ecx, &edx); > thres_count = ebx & 0x07; > @@ -420,19 +422,19 @@ static int pkg_temp_thermal_device_add(unsigned int cpu) > goto err_ret_unlock; > } > > - spin_lock(&pkg_work_lock); > + spin_lock_irqsave(&pkg_work_lock, flags); > if (topology_physical_package_id(cpu) > max_phy_id) > max_phy_id = topology_physical_package_id(cpu); > temp = krealloc(pkg_work_scheduled, > (max_phy_id+1) * sizeof(u8), GFP_ATOMIC); > if (!temp) { > - spin_unlock(&pkg_work_lock); > + spin_unlock_irqrestore(&pkg_work_lock, flags); > err = -ENOMEM; > goto err_ret_free; > } > pkg_work_scheduled = temp; > pkg_work_scheduled[topology_physical_package_id(cpu)] = 0; > - spin_unlock(&pkg_work_lock); > + spin_unlock_irqrestore(&pkg_work_lock, flags); > > phy_dev_entry->phys_proc_id = topology_physical_package_id(cpu); > phy_dev_entry->first_cpu = cpu; -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/thermal/x86_pkg_temp_thermal.c b/drivers/thermal/x86_pkg_temp_thermal.c index f36950e..7722cb9 100644 --- a/drivers/thermal/x86_pkg_temp_thermal.c +++ b/drivers/thermal/x86_pkg_temp_thermal.c @@ -316,18 +316,19 @@ static void pkg_temp_thermal_threshold_work_fn(struct work_struct *work) int phy_id = topology_physical_package_id(cpu); struct phy_dev_entry *phdev = pkg_temp_thermal_get_phy_entry(cpu); bool notify = false; + unsigned long flags; if (!phdev) return; - spin_lock(&pkg_work_lock); + spin_lock_irqsave(&pkg_work_lock, flags); ++pkg_work_cnt; if (unlikely(phy_id > max_phy_id)) { - spin_unlock(&pkg_work_lock); + spin_unlock_irqrestore(&pkg_work_lock, flags); return; } pkg_work_scheduled[phy_id] = 0; - spin_unlock(&pkg_work_lock); + spin_unlock_irqrestore(&pkg_work_lock, flags); enable_pkg_thres_interrupt(); rdmsrl(MSR_IA32_PACKAGE_THERM_STATUS, msr_val); @@ -397,6 +398,7 @@ static int pkg_temp_thermal_device_add(unsigned int cpu) int thres_count; u32 eax, ebx, ecx, edx; u8 *temp; + unsigned long flags; cpuid(6, &eax, &ebx, &ecx, &edx); thres_count = ebx & 0x07; @@ -420,19 +422,19 @@ static int pkg_temp_thermal_device_add(unsigned int cpu) goto err_ret_unlock; } - spin_lock(&pkg_work_lock); + spin_lock_irqsave(&pkg_work_lock, flags); if (topology_physical_package_id(cpu) > max_phy_id) max_phy_id = topology_physical_package_id(cpu); temp = krealloc(pkg_work_scheduled, (max_phy_id+1) * sizeof(u8), GFP_ATOMIC); if (!temp) { - spin_unlock(&pkg_work_lock); + spin_unlock_irqrestore(&pkg_work_lock, flags); err = -ENOMEM; goto err_ret_free; } pkg_work_scheduled = temp; pkg_work_scheduled[topology_physical_package_id(cpu)] = 0; - spin_unlock(&pkg_work_lock); + spin_unlock_irqrestore(&pkg_work_lock, flags); phy_dev_entry->phys_proc_id = topology_physical_package_id(cpu); phy_dev_entry->first_cpu = cpu;
x86_pkg_temp receives thermal notifications via a callback from a therm_throt driver, where thermal interrupts are processed. This callback is pkg_temp_thermal_platform_thermal_notify. Here to avoid multiple interrupts from cores in a package, we disable the source and also set a variable to avoid scheduling delayed work function. This variable is protected via spin_lock_irqsave. On one buggy platform, we still receiving interrupts even if the source is disabled. This can cause deadlock/lockdep warning, when interrupt is generated while under spinlock in work function. Change spin_lock to spin_lock_irqsave and spin_unlock to spin_unlock_irqrestore as the data it is trying to protect can also be modified in a notification call called from interrupt handler. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> --- drivers/thermal/x86_pkg_temp_thermal.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-)