Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751976AbaAXQl4 (ORCPT ); Fri, 24 Jan 2014 11:41:56 -0500 Received: from mail-ie0-f180.google.com ([209.85.223.180]:52502 "EHLO mail-ie0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751242AbaAXQla (ORCPT ); Fri, 24 Jan 2014 11:41:30 -0500 From: =?UTF-8?q?Adrien=20Verg=C3=A9?= To: Russell King Cc: =?UTF-8?q?Adrien=20Verg=C3=A9?= , Catalin Marinas , Will Deacon , Ben Dooks , "zhangwei(Jovi)" , Andrew Morton , Randy Dunlap , Mathieu Poirier , Christopher Covington , Dirk Behme , Michel Dagenais , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH V2 5/6] ARM CoreSight: ETM: Add PID control support Date: Fri, 24 Jan 2014 11:40:55 -0500 Message-Id: <1390581656-16372-6-git-send-email-adrienverge@gmail.com> X-Mailer: git-send-email 1.8.5.2 In-Reply-To: <1390581656-16372-1-git-send-email-adrienverge@gmail.com> References: <1390581656-16372-1-git-send-email-adrienverge@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In the same manner as for enabling tracing, an entry is created in sysfs to set the PID that triggers tracing. This change is effective only if CONFIG_PID_IN_CONTEXTIDR is set, and thus is not compatible with PID namespaces. Signed-off-by: Adrien Vergé --- arch/arm/include/asm/hardware/coresight.h | 5 ++ arch/arm/kernel/etm.c | 82 ++++++++++++++++++++++++++++--- 2 files changed, 80 insertions(+), 7 deletions(-) diff --git a/arch/arm/include/asm/hardware/coresight.h b/arch/arm/include/asm/hardware/coresight.h index 8c50cf6..2051af0 100644 --- a/arch/arm/include/asm/hardware/coresight.h +++ b/arch/arm/include/asm/hardware/coresight.h @@ -98,6 +98,11 @@ #define ETMR_ADDRCOMP_VAL(x) (0x40 + (x) * 4) #define ETMR_ADDRCOMP_ACC_TYPE(x) (0x80 + (x) * 4) +#ifdef CONFIG_PID_IN_CONTEXTIDR +#define ETMR_CTXIDCOMP_VAL(x) (0x1b0 + (x) * 4) +#define ETMR_CTXIDCOMP_MASK (0x1bc) +#endif + /* ETM status register, "ETM Architecture", 3.3.2 */ #define ETMR_STATUS (0x10) #define ETMST_OVERFLOW BIT(0) diff --git a/arch/arm/kernel/etm.c b/arch/arm/kernel/etm.c index 4442e5c..54b5128 100644 --- a/arch/arm/kernel/etm.c +++ b/arch/arm/kernel/etm.c @@ -40,12 +40,14 @@ struct tracectx { void __iomem *etm_regs; unsigned long flags; int naddrcmppairs; + int nctxidcmp; int etm_portsz; struct device *dev; struct clk *emu_clk; struct mutex mutex; unsigned long addrrange_start; unsigned long addrrange_end; + int pid; }; static struct tracectx tracer; @@ -59,14 +61,18 @@ static inline bool trace_isrunning(struct tracectx *t) * Setups ETM to trace only when: * - address between start and end * or address not between start and end (if exclude) + * - in user-space when process id equals pid, + * in kernel-space (if pid == 0), + * always (if pid == -1) * - 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) +static int etm_setup(struct tracectx *t, int n, + unsigned long start, unsigned long end, int exclude, + int pid, + int data) { - u32 flags = ETMAAT_ARM | ETMAAT_IGNCONTEXTID | ETMAAT_NSONLY | \ - ETMAAT_NOVALCMP; + u32 flags = ETMAAT_ARM | ETMAAT_NSONLY | ETMAAT_NOVALCMP; if (n < 1 || n > t->naddrcmppairs) return -EINVAL; @@ -75,6 +81,23 @@ static int etm_setup_address_range(struct tracectx *t, int n, * to bits in a word */ n--; +#ifdef CONFIG_PID_IN_CONTEXTIDR + if (pid < 0) { + /* ignore Context ID */ + flags |= ETMAAT_IGNCONTEXTID; + } else { + flags |= ETMAAT_VALUE1; + + /* Set up the first Context ID comparator. + Process ID is found in the 24 first bits of Context ID + (provided by CONFIG_PID_IN_CONTEXTIDR) */ + etm_writel(t, pid << 8, ETMR_CTXIDCOMP_VAL(0)); + etm_writel(t, 0xff, ETMR_CTXIDCOMP_MASK); + } +#else + flags |= ETMAAT_IGNCONTEXTID; +#endif + if (data) flags |= ETMAAT_DLOADSTORE; else @@ -124,8 +147,10 @@ static int trace_start(struct tracectx *t) return -EFAULT; } - etm_setup_address_range(t, 1, t->addrrange_start, t->addrrange_end, - 0, 0); + etm_setup(t, 1, + t->addrrange_start, t->addrrange_end, 0, + t->pid, + 0); etm_writel(t, 0, ETMR_TRACEENCTRL2); etm_writel(t, 0, ETMR_TRACESSCTRL); etm_writel(t, 0x6f, ETMR_TRACEENEVT); @@ -486,6 +511,7 @@ static ssize_t trace_info_show(struct device *dev, return sprintf(buf, "Trace buffer len: %d\n" "Addr comparator pairs: %d\n" + "Ctx ID comparators: %d\n" "ETBR_WRITEADDR:\t%08x\n" "ETBR_READADDR:\t%08x\n" "ETBR_STATUS:\t%08x\n" @@ -494,6 +520,7 @@ static ssize_t trace_info_show(struct device *dev, "ETMR_STATUS:\t%08x\n", datalen, tracer.naddrcmppairs, + tracer.nctxidcmp, etb_wa, etb_ra, etb_st, @@ -566,6 +593,36 @@ static ssize_t trace_addrrange_store(struct device *dev, DEVICE_ATTR(trace_addrrange, S_IRUGO|S_IWUSR, trace_addrrange_show, trace_addrrange_store); +#ifdef CONFIG_PID_IN_CONTEXTIDR +static ssize_t trace_pid_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%d\n", tracer.pid); +} + +static ssize_t trace_pid_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t n) +{ + int pid; + + if (tracer.flags & TRACER_RUNNING) + return -EBUSY; + + if (sscanf(buf, "%i", &pid) != 1) + return -EINVAL; + + mutex_lock(&tracer.mutex); + tracer.pid = pid; + mutex_unlock(&tracer.mutex); + + return n; +} + +DEVICE_ATTR(trace_pid, S_IRUGO|S_IWUSR, trace_pid_show, trace_pid_store); +#endif + static int etm_probe(struct amba_device *dev, const struct amba_id *id) { struct tracectx *t = &tracer; @@ -595,6 +652,7 @@ static int etm_probe(struct amba_device *dev, const struct amba_id *id) t->etm_portsz = 1; t->addrrange_start = (unsigned long) _stext; t->addrrange_end = (unsigned long) _etext; + t->pid = -1; /* trace everything */ etm_unlock(t); (void)etm_readl(t, ETMMR_PDSR); @@ -602,6 +660,7 @@ static int etm_probe(struct amba_device *dev, const struct amba_id *id) (void)etm_readl(&tracer, ETMMR_OSSRR); t->naddrcmppairs = etm_readl(t, ETMR_CONFCODE) & 0xf; + t->nctxidcmp = (etm_readl(t, ETMR_CONFCODE) >> 24) & 0x3; etm_writel(t, 0x440, ETMR_CTRL); etm_lock(t); @@ -609,7 +668,7 @@ static int etm_probe(struct amba_device *dev, const struct amba_id *id) if (ret) goto out_unmap; - /* failing to create any of these three is not fatal */ + /* failing to create any of these four is not fatal */ ret = device_create_file(&dev->dev, &dev_attr_trace_info); if (ret) dev_dbg(&dev->dev, "Failed to create trace_info in sysfs\n"); @@ -622,6 +681,12 @@ static int etm_probe(struct amba_device *dev, const struct amba_id *id) if (ret) dev_dbg(&dev->dev, "Failed to create trace_addrrange in sysfs\n"); +#ifdef CONFIG_PID_IN_CONTEXTIDR + ret = device_create_file(&dev->dev, &dev_attr_trace_pid); + if (ret) + dev_dbg(&dev->dev, "Failed to create trace_pid in sysfs\n"); +#endif + dev_dbg(t->dev, "ETM AMBA driver initialized.\n"); out: @@ -652,6 +717,9 @@ static int etm_remove(struct amba_device *dev) device_remove_file(&dev->dev, &dev_attr_trace_info); device_remove_file(&dev->dev, &dev_attr_trace_mode); device_remove_file(&dev->dev, &dev_attr_trace_addrrange); +#ifdef CONFIG_PID_IN_CONTEXTIDR + device_remove_file(&dev->dev, &dev_attr_trace_pid); +#endif return 0; } -- 1.8.5.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/