Re: [PATCH v2 5/7] perf cs-etm: Add helper cs_etm__get_pid_fmt()
On Thu, Feb 04, 2021 at 10:54:24AM +, Suzuki Kuruppassery Poulose wrote: [...] > > > > +int cs_etm__get_pid_fmt(u8 trace_chan_id, u64 *pid_fmt) > > > > +{ > > > > + struct int_node *inode; > > > > + u64 *metadata, val; > > > > + > > > > + inode = intlist__find(traceid_list, trace_chan_id); > > > > + if (!inode) > > > > + return -EINVAL; > > > > + > > > > + metadata = inode->priv; > > > > + > > > > + if (metadata[CS_ETM_MAGIC] == __perf_cs_etmv3_magic) { > > > > + val = metadata[CS_ETM_ETMCR]; > > > > + /* CONTEXTIDR is traced */ > > > > + if (val & BIT(ETM_OPT_CTXTID)) > > > > + *pid_fmt = BIT(ETM_OPT_CTXTID); > > > > + } else { > > > > + val = metadata[CS_ETMV4_TRCCONFIGR]; > > > > + > > > > + *pid_fmt = 0; > > > > + > > > > + /* CONTEXTIDR_EL2 is traced */ > > > > + if (val & (BIT(ETM4_CFG_BIT_VMID) | > > > > BIT(ETM4_CFG_BIT_VMID_OPT))) > > > > + *pid_fmt = BIT(ETM_OPT_CTXTID2); > > > > + > > > > + /* CONTEXTIDR_EL1 is traced */ > > > > + if (val & BIT(ETM4_CFG_BIT_CTXTID)) > > > > > > I haven't looked at how this gets used. But, Shouldn't this be : > > > > > > else if (val & BIT(ETM4_CFG_BIT_CTXTID)) ? > > > > Actually it's deliberately to set both bits ETM_OPT_CTXTID2 and > > ETM_OPT_CTXTID if user has enable configs "contextid1" and > > "contextid2". So this is exactly the reversed flow in the > > function cs_etmv4_get_config(). > > The point is, we don't care if the user selected both options. What we > care is, where can we find the PID. CONTEXTIDR_EL1 or CONTEXTIDR_EL2. > As such, get_pid_fmt simply should make that decision and pass it on. > So, if the CONTEXTIDR_EL2 is selected (which can only be done successfully > on an EL2 kernel), thats our pid. > > So we should return the format for the PID here. i.e > ETM_OPT_CTXTID2 OR ETM_OPT_CTXTID. But not both. Okay, if so I will follow your suggestion. Thanks, Leo
Re: [PATCH v2 5/7] perf cs-etm: Add helper cs_etm__get_pid_fmt()
On 2/4/21 3:47 AM, Leo Yan wrote: On Tue, Feb 02, 2021 at 11:19:22PM +, Suzuki Kuruppassery Poulose wrote: On 2/2/21 4:38 PM, Leo Yan wrote: This patch adds helper function cs_etm__get_pid_fmt(), by passing parameter "traceID", it returns the PID format. Signed-off-by: Leo Yan --- tools/perf/util/cs-etm.c | 43 tools/perf/util/cs-etm.h | 1 + 2 files changed, 44 insertions(+) diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c index a2a369e2fbb6..8194ddbd01e5 100644 --- a/tools/perf/util/cs-etm.c +++ b/tools/perf/util/cs-etm.c @@ -7,6 +7,7 @@ */ #include +#include #include #include #include @@ -156,6 +157,48 @@ int cs_etm__get_cpu(u8 trace_chan_id, int *cpu) return 0; } +/* + * The returned PID format is presented by two bits: + * + * Bit ETM_OPT_CTXTID: CONTEXTIDR or CONTEXTIDR_EL1 is traced; + * Bit ETM_OPT_CTXTID2: CONTEXTIDR_EL2 is traced. + * + * It's possible that these two bits are set together, this means the tracing + * contains PIDs for both CONTEXTIDR_EL1 and CONTEXTIDR_EL2. This is a bit confusing. If both the bits are set, the session was run on an EL2 kernel. Thus, the PID is always in CONTEXTIDR_EL2. Sorry for confusion. I'd like to rephrase as: It's possible that the two bits ETM_OPT_CTXTID and ETM_OPT_CTXTID2 are enabled at the same time when the session runs on an EL2 kernel. This means the CONTEXTIDR_EL1 and CONTEXTIDR_EL2 both will be recorded in the trace data, the tool will selectively use CONTEXTIDR_EL2 as PID. + */ +int cs_etm__get_pid_fmt(u8 trace_chan_id, u64 *pid_fmt) +{ + struct int_node *inode; + u64 *metadata, val; + + inode = intlist__find(traceid_list, trace_chan_id); + if (!inode) + return -EINVAL; + + metadata = inode->priv; + + if (metadata[CS_ETM_MAGIC] == __perf_cs_etmv3_magic) { + val = metadata[CS_ETM_ETMCR]; + /* CONTEXTIDR is traced */ + if (val & BIT(ETM_OPT_CTXTID)) + *pid_fmt = BIT(ETM_OPT_CTXTID); + } else { + val = metadata[CS_ETMV4_TRCCONFIGR]; + + *pid_fmt = 0; + + /* CONTEXTIDR_EL2 is traced */ + if (val & (BIT(ETM4_CFG_BIT_VMID) | BIT(ETM4_CFG_BIT_VMID_OPT))) + *pid_fmt = BIT(ETM_OPT_CTXTID2); + + /* CONTEXTIDR_EL1 is traced */ + if (val & BIT(ETM4_CFG_BIT_CTXTID)) I haven't looked at how this gets used. But, Shouldn't this be : else if (val & BIT(ETM4_CFG_BIT_CTXTID)) ? Actually it's deliberately to set both bits ETM_OPT_CTXTID2 and ETM_OPT_CTXTID if user has enable configs "contextid1" and "contextid2". So this is exactly the reversed flow in the function cs_etmv4_get_config(). The point is, we don't care if the user selected both options. What we care is, where can we find the PID. CONTEXTIDR_EL1 or CONTEXTIDR_EL2. As such, get_pid_fmt simply should make that decision and pass it on. So, if the CONTEXTIDR_EL2 is selected (which can only be done successfully on an EL2 kernel), thats our pid. So we should return the format for the PID here. i.e ETM_OPT_CTXTID2 OR ETM_OPT_CTXTID. But not both. Cheers Suzuki
Re: [PATCH v2 5/7] perf cs-etm: Add helper cs_etm__get_pid_fmt()
On Tue, Feb 02, 2021 at 11:19:22PM +, Suzuki Kuruppassery Poulose wrote: > On 2/2/21 4:38 PM, Leo Yan wrote: > > This patch adds helper function cs_etm__get_pid_fmt(), by passing > > parameter "traceID", it returns the PID format. > > > > Signed-off-by: Leo Yan > > --- > > tools/perf/util/cs-etm.c | 43 > > tools/perf/util/cs-etm.h | 1 + > > 2 files changed, 44 insertions(+) > > > > diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c > > index a2a369e2fbb6..8194ddbd01e5 100644 > > --- a/tools/perf/util/cs-etm.c > > +++ b/tools/perf/util/cs-etm.c > > @@ -7,6 +7,7 @@ > >*/ > > #include > > +#include > > #include > > #include > > #include > > @@ -156,6 +157,48 @@ int cs_etm__get_cpu(u8 trace_chan_id, int *cpu) > > return 0; > > } > > +/* > > + * The returned PID format is presented by two bits: > > + * > > + * Bit ETM_OPT_CTXTID: CONTEXTIDR or CONTEXTIDR_EL1 is traced; > > + * Bit ETM_OPT_CTXTID2: CONTEXTIDR_EL2 is traced. > > + * > > + * It's possible that these two bits are set together, this means the > > tracing > > + * contains PIDs for both CONTEXTIDR_EL1 and CONTEXTIDR_EL2. > > This is a bit confusing. If both the bits are set, the session > was run on an EL2 kernel. Thus, the PID is always in CONTEXTIDR_EL2. Sorry for confusion. I'd like to rephrase as: It's possible that the two bits ETM_OPT_CTXTID and ETM_OPT_CTXTID2 are enabled at the same time when the session runs on an EL2 kernel. This means the CONTEXTIDR_EL1 and CONTEXTIDR_EL2 both will be recorded in the trace data, the tool will selectively use CONTEXTIDR_EL2 as PID. > > + */ > > +int cs_etm__get_pid_fmt(u8 trace_chan_id, u64 *pid_fmt) > > +{ > > + struct int_node *inode; > > + u64 *metadata, val; > > + > > + inode = intlist__find(traceid_list, trace_chan_id); > > + if (!inode) > > + return -EINVAL; > > + > > + metadata = inode->priv; > > + > > + if (metadata[CS_ETM_MAGIC] == __perf_cs_etmv3_magic) { > > + val = metadata[CS_ETM_ETMCR]; > > + /* CONTEXTIDR is traced */ > > + if (val & BIT(ETM_OPT_CTXTID)) > > + *pid_fmt = BIT(ETM_OPT_CTXTID); > > + } else { > > + val = metadata[CS_ETMV4_TRCCONFIGR]; > > + > > + *pid_fmt = 0; > > + > > + /* CONTEXTIDR_EL2 is traced */ > > + if (val & (BIT(ETM4_CFG_BIT_VMID) | BIT(ETM4_CFG_BIT_VMID_OPT))) > > + *pid_fmt = BIT(ETM_OPT_CTXTID2); > > + > > + /* CONTEXTIDR_EL1 is traced */ > > + if (val & BIT(ETM4_CFG_BIT_CTXTID)) > > I haven't looked at how this gets used. But, Shouldn't this be : > > else if (val & BIT(ETM4_CFG_BIT_CTXTID)) ? Actually it's deliberately to set both bits ETM_OPT_CTXTID2 and ETM_OPT_CTXTID if user has enable configs "contextid1" and "contextid2". So this is exactly the reversed flow in the function cs_etmv4_get_config(). Thanks, Leo
Re: [PATCH v2 5/7] perf cs-etm: Add helper cs_etm__get_pid_fmt()
On 2/2/21 4:38 PM, Leo Yan wrote: This patch adds helper function cs_etm__get_pid_fmt(), by passing parameter "traceID", it returns the PID format. Signed-off-by: Leo Yan --- tools/perf/util/cs-etm.c | 43 tools/perf/util/cs-etm.h | 1 + 2 files changed, 44 insertions(+) diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c index a2a369e2fbb6..8194ddbd01e5 100644 --- a/tools/perf/util/cs-etm.c +++ b/tools/perf/util/cs-etm.c @@ -7,6 +7,7 @@ */ #include +#include #include #include #include @@ -156,6 +157,48 @@ int cs_etm__get_cpu(u8 trace_chan_id, int *cpu) return 0; } +/* + * The returned PID format is presented by two bits: + * + * Bit ETM_OPT_CTXTID: CONTEXTIDR or CONTEXTIDR_EL1 is traced; + * Bit ETM_OPT_CTXTID2: CONTEXTIDR_EL2 is traced. + * + * It's possible that these two bits are set together, this means the tracing + * contains PIDs for both CONTEXTIDR_EL1 and CONTEXTIDR_EL2. This is a bit confusing. If both the bits are set, the session was run on an EL2 kernel. Thus, the PID is always in CONTEXTIDR_EL2. + */ +int cs_etm__get_pid_fmt(u8 trace_chan_id, u64 *pid_fmt) +{ + struct int_node *inode; + u64 *metadata, val; + + inode = intlist__find(traceid_list, trace_chan_id); + if (!inode) + return -EINVAL; + + metadata = inode->priv; + + if (metadata[CS_ETM_MAGIC] == __perf_cs_etmv3_magic) { + val = metadata[CS_ETM_ETMCR]; + /* CONTEXTIDR is traced */ + if (val & BIT(ETM_OPT_CTXTID)) + *pid_fmt = BIT(ETM_OPT_CTXTID); + } else { + val = metadata[CS_ETMV4_TRCCONFIGR]; + + *pid_fmt = 0; + + /* CONTEXTIDR_EL2 is traced */ + if (val & (BIT(ETM4_CFG_BIT_VMID) | BIT(ETM4_CFG_BIT_VMID_OPT))) + *pid_fmt = BIT(ETM_OPT_CTXTID2); + + /* CONTEXTIDR_EL1 is traced */ + if (val & BIT(ETM4_CFG_BIT_CTXTID)) I haven't looked at how this gets used. But, Shouldn't this be : else if (val & BIT(ETM4_CFG_BIT_CTXTID)) ? Suzuki