| Message ID | 1522379724-30648-5-git-send-email-leo.yan@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | Coresight: Support panic kdump | expand |
On Fri, Mar 30, 2018 at 11:15:22AM +0800, Leo Yan wrote: > Since Coresight panic kdump functionality has been ready, this patch is > to hook panic callback function for ETB/ETF driver. The driver data > structure has allocated a buffer when the session started, so simply > save tracing data into this buffer when panic happens and update buffer > related info for kdump. > > Signed-off-by: Leo Yan <leo.yan@linaro.org> > --- > drivers/hwtracing/coresight/coresight-tmc-etf.c | 30 +++++++++++++++++++++++++ > 1 file changed, 30 insertions(+) > > diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c > index e2513b7..d20d546 100644 > --- a/drivers/hwtracing/coresight/coresight-tmc-etf.c > +++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c > @@ -504,6 +504,35 @@ static void tmc_update_etf_buffer(struct coresight_device *csdev, > CS_LOCK(drvdata->base); > } > > +static void tmc_panic_cb(void *data) I would call the function tmc_kdump_panic_cb()... That way there is absolutely no confusion as to what it does. > +{ > + struct coresight_device *csdev = (struct coresight_device *)data; > + struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); > + unsigned long flags; > + > + if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETB && > + drvdata->config_type != TMC_CONFIG_TYPE_ETF)) > + return; > + > + if (drvdata->mode == CS_MODE_DISABLED) > + return; This is racy - between the check and acquiring the spinlock someone may beat you to it. > + > + spin_lock_irqsave(&drvdata->spinlock, flags); if (drvdata->mode == CS_MODE_DISABLED) goto out; drvdata->mode = CS_MODE_DISABLED > + > + CS_UNLOCK(drvdata->base); > + > + tmc_flush_and_stop(drvdata); > + tmc_etb_dump_hw(drvdata); > + > + CS_LOCK(drvdata->base); > + > + /* Update buffer info for panic dump */ > + csdev->kdump_buf = drvdata->buf; > + csdev->kdump_buf_sz = drvdata->len; out: > + > + spin_unlock_irqrestore(&drvdata->spinlock, flags); > +} > + > static const struct coresight_ops_sink tmc_etf_sink_ops = { > .enable = tmc_enable_etf_sink, > .disable = tmc_disable_etf_sink, > @@ -512,6 +541,7 @@ static const struct coresight_ops_sink tmc_etf_sink_ops = { > .set_buffer = tmc_set_etf_buffer, > .reset_buffer = tmc_reset_etf_buffer, > .update_buffer = tmc_update_etf_buffer, > + .panic_cb = tmc_panic_cb, > }; > > static const struct coresight_ops_link tmc_etf_link_ops = { > -- > 2.7.4 >
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c index e2513b7..d20d546 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etf.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c @@ -504,6 +504,35 @@ static void tmc_update_etf_buffer(struct coresight_device *csdev, CS_LOCK(drvdata->base); } +static void tmc_panic_cb(void *data) +{ + struct coresight_device *csdev = (struct coresight_device *)data; + struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); + unsigned long flags; + + if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETB && + drvdata->config_type != TMC_CONFIG_TYPE_ETF)) + return; + + if (drvdata->mode == CS_MODE_DISABLED) + return; + + spin_lock_irqsave(&drvdata->spinlock, flags); + + CS_UNLOCK(drvdata->base); + + tmc_flush_and_stop(drvdata); + tmc_etb_dump_hw(drvdata); + + CS_LOCK(drvdata->base); + + /* Update buffer info for panic dump */ + csdev->kdump_buf = drvdata->buf; + csdev->kdump_buf_sz = drvdata->len; + + spin_unlock_irqrestore(&drvdata->spinlock, flags); +} + static const struct coresight_ops_sink tmc_etf_sink_ops = { .enable = tmc_enable_etf_sink, .disable = tmc_disable_etf_sink, @@ -512,6 +541,7 @@ static const struct coresight_ops_sink tmc_etf_sink_ops = { .set_buffer = tmc_set_etf_buffer, .reset_buffer = tmc_reset_etf_buffer, .update_buffer = tmc_update_etf_buffer, + .panic_cb = tmc_panic_cb, }; static const struct coresight_ops_link tmc_etf_link_ops = {
Since Coresight panic kdump functionality has been ready, this patch is to hook panic callback function for ETB/ETF driver. The driver data structure has allocated a buffer when the session started, so simply save tracing data into this buffer when panic happens and update buffer related info for kdump. Signed-off-by: Leo Yan <leo.yan@linaro.org> --- drivers/hwtracing/coresight/coresight-tmc-etf.c | 30 +++++++++++++++++++++++++ 1 file changed, 30 insertions(+) -- 2.7.4