In the same manner as for enabling tracing, an entry is created in sysfs to set the address range that triggers tracing.
Signed-off-by: Adrien Vergé <adrienve...@gmail.com> Cc: Russell King <li...@arm.linux.org.uk> Cc: Ben Dooks <ben.do...@codethink.co.uk> Cc: Will Deacon <will.dea...@arm.com> Cc: Dietmar Eggemann <dietmar.eggem...@arm.com> Cc: Andrew Morton <a...@linux-foundation.org> Cc: "zhangwei(Jovi)" <jovi.zhang...@huawei.com> Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org> Cc: Randy Dunlap <rdun...@infradead.org> --- arch/arm/kernel/etm.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 50 insertions(+), 3 deletions(-) diff --git a/arch/arm/kernel/etm.c b/arch/arm/kernel/etm.c index bd7e8e4..a72382b 100644 --- a/arch/arm/kernel/etm.c +++ b/arch/arm/kernel/etm.c @@ -44,6 +44,8 @@ struct tracectx { struct device *dev; struct clk *emu_clk; struct mutex mutex; + unsigned long addrrange_start; + unsigned long addrrange_end; }; static struct tracectx tracer; @@ -53,6 +55,13 @@ static inline bool trace_isrunning(struct tracectx *t) return !!(t->flags & TRACER_RUNNING); } +/* + * Setups ETM to trace only when: + * - address between start and end + * or address not between start and end (if exclude) + * - trace executed instructions + * or trace loads and stores (if data) + */ static int etm_setup_address_range(struct tracectx *t, int n, unsigned long start, unsigned long end, int exclude, int data) { @@ -115,8 +124,8 @@ static int trace_start(struct tracectx *t) return -EFAULT; } - etm_setup_address_range(t, 1, (unsigned long)_stext, - (unsigned long)_etext, 0, 0); + etm_setup_address_range(t, 1, t->addrrange_start, t->addrrange_end, + 0, 0); etm_writel(t, 0, ETMR_TRACEENCTRL2); etm_writel(t, 0, ETMR_TRACESSCTRL); etm_writel(t, 0x6f, ETMR_TRACEENEVT); @@ -532,6 +541,37 @@ static ssize_t trace_mode_store(struct kobject *kobj, static struct kobj_attribute trace_mode_attr = __ATTR(trace_mode, 0644, trace_mode_show, trace_mode_store); +static ssize_t trace_addrrange_show(struct kobject *kobj, + struct kobj_attribute *attr, + char *buf) +{ + return sprintf(buf, "%08lx - %08lx\n", tracer.addrrange_start, + tracer.addrrange_end); +} + +static ssize_t trace_addrrange_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t n) +{ + unsigned long start, end; + + if (tracer.flags & TRACER_RUNNING) + return -EBUSY; + + if (sscanf(buf, "%08lx - %08lx", &start, &end) != 2) + return -EINVAL; + + mutex_lock(&tracer.mutex); + tracer.addrrange_start = start; + tracer.addrrange_end = end; + mutex_unlock(&tracer.mutex); + + return n; +} + +static struct kobj_attribute trace_addrrange_attr = + __ATTR(trace_addrrange, 0644, trace_addrrange_show, trace_addrrange_store); + static int etm_probe(struct amba_device *dev, const struct amba_id *id) { struct tracectx *t = &tracer; @@ -559,6 +599,8 @@ static int etm_probe(struct amba_device *dev, const struct amba_id *id) t->dev = &dev->dev; t->flags = TRACER_CYCLE_ACC; t->etm_portsz = 1; + t->addrrange_start = (unsigned long) _stext; + t->addrrange_end = (unsigned long) _etext; etm_unlock(t); (void)etm_readl(t, ETMMR_PDSR); @@ -574,7 +616,7 @@ static int etm_probe(struct amba_device *dev, const struct amba_id *id) if (ret) goto out_unmap; - /* failing to create any of these two is not fatal */ + /* failing to create any of these three is not fatal */ ret = sysfs_create_file(&dev->dev.kobj, &trace_info_attr.attr); if (ret) dev_dbg(&dev->dev, "Failed to create trace_info in sysfs\n"); @@ -583,6 +625,10 @@ static int etm_probe(struct amba_device *dev, const struct amba_id *id) if (ret) dev_dbg(&dev->dev, "Failed to create trace_mode in sysfs\n"); + ret = sysfs_create_file(&dev->dev.kobj, &trace_addrrange_attr.attr); + if (ret) + dev_dbg(&dev->dev, "Failed to create trace_addrrange in sysfs\n"); + dev_dbg(t->dev, "ETM AMBA driver initialized.\n"); out: @@ -612,6 +658,7 @@ static int etm_remove(struct amba_device *dev) sysfs_remove_file(&dev->dev.kobj, &trace_running_attr.attr); sysfs_remove_file(&dev->dev.kobj, &trace_info_attr.attr); sysfs_remove_file(&dev->dev.kobj, &trace_mode_attr.attr); + sysfs_remove_file(&dev->dev.kobj, &trace_addrrange_attr.attr); return 0; } -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/