perf/core improvements and fixes
Arnaldo Carvalho de Melo
maintainerHi Ingo,
Please consider pulling,
- Arnaldo
The following changes since commit 030ba6cd105c68ce919c5e239853b567490cd059:
perf/x86/intel: Use new topology_max_smt_threads() in HT leak workaround (2016-06-03 09:41:25 +0200)
are available in the git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git tags/perf-core-for-mingo-20160606
for you to fetch changes up to 7db91f251056f90fec4121f028680ab3153a0f3c:
perf config: Handle the error when config set is NULL at collect_config() (2016-06-06 17:43:19 -0300)
----------------------------------------------------------------
perf/core improvements and fixes:
User visible:
- Tooling support for TopDown counters, recently added to the kernel (Andi Kleen)
- Show call graphs in 'perf script' when 1st event doesn't have it but some other has (He Kuang)
- Fix terminal cleanup when handling invalid .perfconfig files in 'perf top' (Taeung Song)
Build fixes:
- Respect CROSS_COMPILE for the linker in libapi (Lucas Stach)
Infrastructure:
- Fix perf_evlist__alloc_mmap() failure path (Wang Nan)
- Provide way to extract integer value from format_field (Arnaldo Carvalho de Melo)
----------------------------------------------------------------
Andi Kleen (5):
perf test: Ignore .scale and other special files
perf stat: Basic support for TopDown in perf stat perf stat: Add computation of TopDown formulas
perf stat: Print topology/time headers with --metric-only perf stat: Add missing aggregation headers for --metric-only CSV
Arnaldo Carvalho de Melo (1):
perf evsel: Provide way to extract integer value from format_field
He Kuang (1):
perf script: Show call graphs when 1st event doesn't have it but some other has
Lucas Stach (1):
tools lib api: Respect CROSS_COMPILE for the linker
Taeung Song (2):
perf config: Fix abnormal termination at perf_parse_file() perf config: Handle the error when config set is NULL at collect_config()
Wang Nan (1):
perf evlist: Fix alloc_mmap() failure path
tools/lib/api/Makefile | 1 + tools/perf/Documentation/perf-stat.txt | 32 +++++++ tools/perf/arch/x86/util/Build | 1 + tools/perf/arch/x86/util/group.c | 27 ++++++ tools/perf/builtin-script.c | 23 +++-- tools/perf/builtin-stat.c | 165 ++++++++++++++++++++++++++++++--- tools/perf/tests/parse-events.c | 4 +- tools/perf/util/config.c | 22 +++-- tools/perf/util/evlist.c | 5 +- tools/perf/util/evsel.c | 25 +++-- tools/perf/util/evsel.h | 2 + tools/perf/util/group.h | 7 ++ tools/perf/util/parse-events.l | 1 + tools/perf/util/stat-shadow.c | 162 ++++++++++++++++++++++++++++++++ tools/perf/util/stat.c | 5 + tools/perf/util/stat.h | 5 + 16 files changed, 441 insertions(+), 46 deletions(-) create mode 100644 tools/perf/arch/x86/util/group.c create mode 100644 tools/perf/util/group.h
Arnaldo Carvalho de Melo
maintainerPATCH 1/11 perf evsel: Provide way to extract integer value from format_field
From: Arnaldo Carvalho de Melo <[email protected]>
Out of perf_evsel__intval(), that requires passing the variable name, that will then be searched in the list of tracepoint variables for the given evsel.
In cases such as syscall file descriptor ("fd") tracking, this is wasteful, we need just to use perf_evsel__field() and cache the format_field.
--- tools/perf/util/evsel.c | 25 +++++++++++++++---------- tools/perf/util/evsel.h | 2 ++ 2 files changed, 17 insertions(+), 10 deletions(-)
tools/perf/util/evsel.c +15 -10
@@ -2251,17 +2251,11 @@ void *perf_evsel__rawptr(struct perf_evsel *evsel, struct perf_sample *sample,return sample->raw_data + offset; } -u64 perf_evsel__intval (struct perf_evsel *evsel,struct perf_sample *sample, -const char *name) +u64 format_field__intval (struct format_field *field,struct perf_sample *sample, +bool needs_swap) { -struct format_field *field =perf_evsel__field (evsel, name); -void *ptr;u64 value; - -if (!field) -return 0 ; - - ptr = sample->raw_data + field->offset; +void *ptr = sample->raw_data + field->offset;switch (field->size) {case 1 :
@@ -2279,7 +2273,7 @@ u64 perf_evsel__intval(struct perf_evsel *evsel, struct perf_sample *sample,return 0 ; } -if (!evsel->needs_swap) +if (!needs_swap)return value;switch (field->size) {
@@ -2296,6 +2290,17 @@ u64 perf_evsel__intval(struct perf_evsel *evsel, struct perf_sample *sample,return 0 ; } +u64 perf_evsel__intval (struct perf_evsel *evsel,struct perf_sample *sample, +const char *name) +{ +struct format_field *field =perf_evsel__field (evsel, name); + +if (!field) +return 0 ; + +return field ?format_field__intval (field, sample, evsel->needs_swap) :0 ; +} +bool perf_evsel__fallback (struct perf_evsel *evsel,int err,char *msg,size_t msgsize) {
tools/perf/util/evsel.h +2 -0
@@ -261,6 +261,8 @@ static inline char *perf_evsel__strval(struct perf_evsel *evsel,struct format_field ; +u64 format_field__intval (struct format_field *field,struct perf_sample *sample,bool needs_swap); +struct format_field *perf_evsel__field (struct perf_evsel *evsel,const char *name);#define perf_evsel__match (evsel, t, c) \
Signature · 1 line
2.5.5
Arnaldo Carvalho de Melo
maintainerPATCH 2/11 perf evlist: Fix alloc_mmap() failure path
In reply to Arnaldo Carvalho de MeloFrom: Wang Nan <[email protected]>
If zalloc fail, setting evlist->mmap[i].fd is unsafe and perf_evlist__alloc_mmap() should bail out right after that.
--- tools/perf/util/evlist.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
tools/perf/util/evlist.c +4 -1
@@ -946,9 +946,12 @@ static int perf_evlist__alloc_mmap(struct perf_evlist *evlist)if (cpu_map__empty (evlist->cpus)) evlist->nr_mmaps =thread_map__nr (evlist->threads); evlist->mmap =zalloc (evlist->nr_mmaps *sizeof (struct perf_mmap )); +if (!evlist->mmap) +return -ENOMEM ; +for (i =0 ; i < evlist->nr_mmaps; i++) evlist->mmap[i].fd =-1 ; -return evlist->mmap !=NULL ?0 : -ENOMEM ; +return 0 ; }struct mmap_params {
Signature · 1 line
2.5.5
Arnaldo Carvalho de Melo
maintainerPATCH 3/11 tools lib api: Respect CROSS_COMPILE for the linker
In reply to Arnaldo Carvalho de MeloFrom: Lucas Stach <[email protected]>
This fixes cross compilation of libapi.
--- tools/lib/api/Makefile | 1 + 1 file changed, 1 insertion(+)
tools/lib/api/Makefile +1 -0
@@ -10,6 +10,7 @@ endif CC = $(CROSS_COMPILE)gcc AR = $(CROSS_COMPILE)ar +LD = $(CROSS_COMPILE)ld MAKEFLAGS += --no-print-directory
Signature · 1 line
2.5.5
Arnaldo Carvalho de Melo
maintainerPATCH 4/11 perf script: Show call graphs when 1st event doesn't have it but some other has
In reply to Arnaldo Carvalho de MeloFrom: He Kuang <[email protected]>
There's a display inconsistency when there are multiple tracepoint events, some of which have the 'call-graph' config option set but the first one hasn't, i.e. the whole logic for call graph processing is enabled only if the first tracepoint event has call-graph set.
For instance, if we record signal_deliver with call-graph and signal_generate without:
$ perf record -g -a -e signal:signal_deliver -e signal:signal_generate/call-graph=no/
[ perf record: Captured and wrote 0.017 MB perf.data (2 samples) ]
$ perf script
kworker/u2:1 13 [000] 6563.875949: signal:signal_generate: sig=2 errno=0 code=128 comm=perf pid=1313 grp=1 res=0 ff61cc __send_signal+0x3ec ([kernel.kallsyms])
perf 1313 [000] 6563.877584: signal:signal_deliver: sig=2 errno=0 code=128 sa_handler=43115e sa_flags=14000000
7ffff314 get_signal+0x80007f0023a4 ([kernel.kallsyms])
7fffe358 do_signal+0x80007f002028 ([kernel.kallsyms])
7fffa5e8 exit_to_usermode_loop+0x80007f002053 ([kernel.kallsyms])
...Then we exchange the order of these two events in commandline, and keep signal_generate without call-graph.
$ perf record -g -a -e signal:signal_generate/call-graph=no/ -e signal:signal_deliver
[ perf record: Captured and wrote 0.017 MB perf.data (2 samples) ]
$ perf script
kworker/u2:2 1314 [000] 6933.353060: signal:signal_generate: sig=2 errno=0 code=128 comm=perf pid=1321 grp=1 res=0
perf 1321 [000] 6933.353872: signal:signal_deliver: sig=2 errno=0 code=128 sa_handler=43115e sa_flags=14000000This time, the callchain of the event signal_deliver disappeared. The problem is caused by that perf only checks for the first evsel in evlist and decides if callchain should be printed.
This patch traverses all evsels in evlist to see if any of them have callchains, and shows the right result:
$ perf script
kworker/u2:2 1314 [000] 6933.353060: signal:signal_generate: sig=2 errno=0 code=128 comm=perf pid=1321 grp=1 res=0 ff61cc __send_signal+0x3ec ([kernel.kallsyms]) perf 1321 [000] 6933.353872: signal:signal_deliver: sig=2 errno=0 code=128 sa_handler=43115e sa_flags=14000000
7ffff314 get_signal+0x80007f0023a4 ([kernel.kallsyms])
7fffe358 do_signal+0x80007f002028 ([kernel.kallsyms])
7fffa5e8 exit_to_usermode_loop+0x80007f002053 ([kernel.kallsyms])
...--- tools/perf/builtin-script.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-)
tools/perf/builtin-script.c +13 -10
@@ -339,7 +339,7 @@ static void set_print_ip_opts(struct perf_event_attr *attr)*/ static int perf_session__check_output_opt (struct perf_session *session) { -int j; +unsigned int j;struct perf_evsel *evsel;for (j =0 ; j <PERF_TYPE_MAX ; ++j) {
@@ -388,17 +388,20 @@ static int perf_session__check_output_opt(struct perf_session *session)struct perf_event_attr *attr; j =PERF_TYPE_TRACEPOINT ; - evsel =perf_session__find_first_evtype (session, j); -if (evsel ==NULL ) - goto out; - attr = &evsel->attr; +evlist__for_each (session->evlist, evsel) { +if (evsel->attr.type != j) +continue ; + + attr = &evsel->attr; -if (attr->sample_type &PERF_SAMPLE_CALLCHAIN ) { - output[j].fields |=PERF_OUTPUT_IP ; - output[j].fields |=PERF_OUTPUT_SYM ; - output[j].fields |=PERF_OUTPUT_DSO ; -set_print_ip_opts (attr); +if (attr->sample_type &PERF_SAMPLE_CALLCHAIN ) { + output[j].fields |=PERF_OUTPUT_IP ; + output[j].fields |=PERF_OUTPUT_SYM ; + output[j].fields |=PERF_OUTPUT_DSO ; +set_print_ip_opts (attr); + goto out; + } } }
Signature · 1 line
2.5.5
Arnaldo Carvalho de Melo
maintainerPATCH 5/11 perf test: Ignore .scale and other special files
In reply to Arnaldo Carvalho de MeloFrom: Andi Kleen <[email protected]>
'perf test' tries to parse all entries in /sys/devices/cpu/events/. Ignore the special entries like '.scale', which cannot be directly parsed as an event. This patch assumes all files containing a '.' are special and can be ignored.
--- tools/perf/tests/parse-events.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
tools/perf/tests/parse-events.c +2 -2
@@ -1783,8 +1783,8 @@ static int test_pmu_events(void)struct evlist_test e;char name[MAX_NAME ]; -if (!strcmp (ent->d_name,"." ) || - !strcmp (ent->d_name,".." )) +/* Names containing . are special and cannot be used directly */ +if (strchr (ent->d_name,'.' ))continue ;snprintf (name,MAX_NAME ,"cpu/event=%s/u" , ent->d_name);
Signature · 1 line
2.5.5
Arnaldo Carvalho de Melo
maintainerPATCH 6/11 perf stat: Basic support for TopDown in perf stat
In reply to Arnaldo Carvalho de MeloFrom: Andi Kleen <[email protected]>
Add basic plumbing for TopDown in perf stat
TopDown is intended to replace the frontend cycles idle/ backend cycles idle metrics in standard perf stat output. These metrics are not reliable in many workloads, due to out of order effects.
This implements a new --topdown mode in perf stat (similar to --transaction) that measures the pipe line bottlenecks using standardized formulas. The measurement can be all done with 5 counters (one fixed counter)
The result are four metrics:
FrontendBound, BackendBound, BadSpeculation, Retiring
that describe the CPU pipeline behavior on a high level.
The full top down methology has many hierarchical metrics. This implementation only supports level 1 which can be collected without multiplexing. A full implementation of top down on top of perf is available in pmu-tools toplev. (http://github.com/andikleen/pmu-tools)
The current version works on Intel Core CPUs starting with Sandy Bridge, and Atom CPUs starting with Silvermont. In principle the generic metrics should be also implementable on other out of order CPUs.
TopDown level 1 uses a set of abstracted metrics which are generic to out of order CPU cores (although some CPUs may not implement all of them):
topdown-total-slots Available slots in the pipeline topdown-slots-issued Slots issued into the pipeline topdown-slots-retired Slots successfully retired topdown-fetch-bubbles Pipeline gaps in the frontend topdown-recovery-bubbles Pipeline gaps during recovery
from misspeculation
These metrics then allow to compute four useful metrics:
FrontendBound, BackendBound, Retiring, BadSpeculation.
Add a new --topdown options to enable events. When --topdown is specified set up events for all topdown events supported by the kernel. Add topdown-* as a special case to the event parser, as is needed for all events containing -.
The actual code to compute the metrics is in follow-on patches.
v2: Use standard sysctl read function.
v3: Move x86 specific code to arch/
v4: Enable --metric-only implicitly for topdown.
v5: Add --single-thread option to not force per core mode
v6: Fix output order of topdown metrics
v7: Allow combining with -d
v8: Remove --single-thread again
v9: Rename functions, adding arch_ and topdown_.
v10: Expand man page and describe TopDown better Paste intro into commit description.
Print error when malloc fails.
--- tools/perf/Documentation/perf-stat.txt | 32 +++++++++ tools/perf/arch/x86/util/Build | 1 + tools/perf/arch/x86/util/group.c | 27 ++++++++ tools/perf/builtin-stat.c | 119 ++++++++++++++++++++++++++++++++- tools/perf/util/group.h | 7 ++ tools/perf/util/parse-events.l | 1 + 6 files changed, 184 insertions(+), 3 deletions(-) create mode 100644 tools/perf/arch/x86/util/group.c create mode 100644 tools/perf/util/group.h
tools/perf/Documentation/perf-stat.txt +32 -0
@@ -204,6 +204,38 @@ Aggregate counts per physical processor for system-wide mode measurements. --no-aggr:: Do not aggregate counts across all monitored CPUs. +--topdown:: +Print top down level 1 metrics if supported by the CPU. This allows to +determine bottle necks in the CPU pipeline for CPU bound workloads, +by breaking the cycles consumed down into frontend bound, backend bound, +bad speculation and retiring. + +Frontend bound means that the CPU cannot fetch and decode instructions fast +enough. Backend bound means that computation or memory access is the bottle +neck. Bad Speculation means that the CPU wasted cycles due to branch +mispredictions and similar issues. Retiring means that the CPU computed without +an apparently bottleneck. The bottleneck is only the real bottleneck +if the workload is actually bound by the CPU and not by something else. + +For best results it is usually a good idea to use it with interval +mode like -I 1000, as the bottleneck of workloads can change often. + +The top down metrics are collected per core instead of per +CPU thread. Per core mode is automatically enabled +and -a (global monitoring) is needed, requiring root rights or +perf.perf_event_paranoid=-1. + +Topdown uses the full Performance Monitoring Unit, and needs +disabling of the NMI watchdog (as root): +echo 0 > /proc/sys/kernel/nmi_watchdog +for best results. Otherwise the bottlenecks may be inconsistent +on workload with changing phases. + +This enables --metric-only, unless overriden with --no-metric-only. + +To interpret the results it is usually needed to know on which +CPUs the workload runs on. If needed the CPUs can be forced using +taskset. EXAMPLES --------
tools/perf/arch/x86/util/Build +1 -0
@@ -3,6 +3,7 @@ libperf-y += tsc.o libperf-y += pmu.o libperf-y += kvm-stat.o libperf-y += perf_regs.o +libperf-y += group.o libperf-$(CONFIG_DWARF) += dwarf-regs.o libperf-$(CONFIG_BPF_PROLOGUE) += dwarf-regs.o
tools/perf/arch/x86/util/group.c new file +27 -0
@@ -0,0 +1,27 @@ +#include <stdio.h> +#include "api/fs/fs.h" +#include "util/group.h" + +/* +* Check whether we can use a group for top down. +* Without a group may get bad results due to multiplexing. +*/ +bool arch_topdown_check_group (bool *warn) +{ +int n; + +if (sysctl__read_int ("kernel/nmi_watchdog" , &n) <0 ) +return false; +if (n >0 ) { + *warn = true; +return false; + } +return true; +} + +void arch_topdown_group_warn (void ) +{ +fprintf (stderr, +"nmi_watchdog enabled with topdown. May give wrong results.\n" +"Disable with echo 0 > /proc/sys/kernel/nmi_watchdog\n" ); +}
tools/perf/builtin-stat.c +116 -3
183 lines not on this page · raw message
tools/perf/util/group.h new file +7 -0
@@ -0,0 +1,7 @@ +#ifndef GROUP_H +#define GROUP_H 1 + +bool arch_topdown_check_group (bool *warn); +void arch_topdown_group_warn (void ); + +#endif
tools/perf/util/parse-events.l +1 -0
@@ -260,6 +260,7 @@ cycles-ct { return str(yyscanner, PE_KERNEL_PMU_EVENT); } cycles-t { return str(yyscanner, PE_KERNEL_PMU_EVENT); } mem-loads { return str(yyscanner, PE_KERNEL_PMU_EVENT); } mem-stores { return str(yyscanner, PE_KERNEL_PMU_EVENT); } +topdown-[a-z-]+ { return str(yyscanner, PE_KERNEL_PMU_EVENT); } L1-dcache|l1-d|l1d|L1-data | L1-icache|l1-i|l1i|L1-instruction |
Signature · 1 line
2.5.5
Arnaldo Carvalho de Melo
maintainerPATCH 7/11 perf stat: Add computation of TopDown formulas
In reply to Arnaldo Carvalho de MeloFrom: Andi Kleen <[email protected]>
Implement the TopDown formulas in 'perf stat'. The topdown basic metrics reported by the kernel are collected, and the formulas are computed and output as normal metrics.
See the kernel commit exporting the events for details on the used metrics.
Committer note:
Output example:
# perf stat --topdown -a usleep 1
Performance counter stats for 'system wide':
retiring bad speculation frontend bound backend bound
S0-C0 2 23.8% 11.6% 28.3% 36.3% S0-C1 2 16.2% 15.7% 36.5% 31.6%
0.000579956 seconds time elapsed
#
v2: Always print all metrics, only use thresholds for coloring.
v3: Mark retiring over threshold green, not red.
v4: Only print one decimal digit
Fix color printing of one metric
v5: Avoid printing -0.0
v6: Remove extra frontend event lookup
--- tools/perf/util/stat-shadow.c | 162 ++++++++++++++++++++++++++++++++++++++++++ tools/perf/util/stat.c | 5 ++ tools/perf/util/stat.h | 5 ++ 3 files changed, 172 insertions(+)
tools/perf/util/stat-shadow.c +162 -0
@@ -36,6 +36,11 @@ static struct stats runtime_dtlb_cache_stats[NUM_CTX][MAX_NR_CPUS];static struct stats runtime_cycles_in_tx_stats[NUM_CTX ][MAX_NR_CPUS ];static struct stats runtime_transaction_stats[NUM_CTX ][MAX_NR_CPUS ];static struct stats runtime_elision_stats[NUM_CTX ][MAX_NR_CPUS ]; +static struct stats runtime_topdown_total_slots[NUM_CTX ][MAX_NR_CPUS ]; +static struct stats runtime_topdown_slots_issued[NUM_CTX ][MAX_NR_CPUS ]; +static struct stats runtime_topdown_slots_retired[NUM_CTX ][MAX_NR_CPUS ]; +static struct stats runtime_topdown_fetch_bubbles[NUM_CTX ][MAX_NR_CPUS ]; +static struct stats runtime_topdown_recovery_bubbles[NUM_CTX ][MAX_NR_CPUS ];static bool have_frontend_stalled;struct stats walltime_nsecs_stats;
@@ -82,6 +87,11 @@ void perf_stat__reset_shadow_stats(void) sizeof(runtime_transaction_stats));memset (runtime_elision_stats,0 ,sizeof (runtime_elision_stats));memset (&walltime_nsecs_stats,0 ,sizeof (walltime_nsecs_stats)); +memset (runtime_topdown_total_slots,0 ,sizeof (runtime_topdown_total_slots)); +memset (runtime_topdown_slots_retired,0 ,sizeof (runtime_topdown_slots_retired)); +memset (runtime_topdown_slots_issued,0 ,sizeof (runtime_topdown_slots_issued)); +memset (runtime_topdown_fetch_bubbles,0 ,sizeof (runtime_topdown_fetch_bubbles)); +memset (runtime_topdown_recovery_bubbles,0 ,sizeof (runtime_topdown_recovery_bubbles)); }/*
@@ -105,6 +115,16 @@ void perf_stat__update_shadow_stats(struct perf_evsel *counter, u64 *count,update_stats (&runtime_transaction_stats[ctx][cpu], count[0 ]); else if (perf_stat_evsel__is(counter, ELISION_START)) update_stats(&runtime_elision_stats[ctx][cpu], count[0]); + else if (perf_stat_evsel__is(counter, TOPDOWN_TOTAL_SLOTS)) + update_stats(&runtime_topdown_total_slots[ctx][cpu], count[0]); + else if (perf_stat_evsel__is(counter, TOPDOWN_SLOTS_ISSUED)) + update_stats(&runtime_topdown_slots_issued[ctx][cpu], count[0]); + else if (perf_stat_evsel__is(counter, TOPDOWN_SLOTS_RETIRED)) + update_stats(&runtime_topdown_slots_retired[ctx][cpu], count[0]); + else if (perf_stat_evsel__is(counter, TOPDOWN_FETCH_BUBBLES)) + update_stats(&runtime_topdown_fetch_bubbles[ctx][cpu],count[0]); + else if (perf_stat_evsel__is(counter, TOPDOWN_RECOVERY_BUBBLES)) + update_stats(&runtime_topdown_recovery_bubbles[ctx][cpu], count[0]); else if (perf_evsel__match(counter, HARDWARE, HW_STALLED_CYCLES_FRONTEND)) update_stats(&runtime_stalled_cycles_front_stats[ctx][cpu], count[0]); else if (perf_evsel__match(counter, HARDWARE, HW_STALLED_CYCLES_BACKEND))
@@ -302,6 +322,107 @@ static void print_ll_cache_misses(int cpu, out->print_metric (out->ctx, color,"%7.2f%%" ,"of all LL-cache hits" , ratio); } +/* +* High level "TopDown" CPU core pipe line bottleneck break down. +* +* Basic concept following +* Yasin, A Top Down Method for Performance analysis and Counter architecture +* ISPASS14 +* +* The CPU pipeline is divided into 4 areas that can be bottlenecks: +* +* Frontend -> Backend -> Retiring +* BadSpeculation in addition means out of order execution that is thrown away +* (for example branch mispredictions) +* Frontend is instruction decoding. +* Backend is execution, like computation and accessing data in memory +* Retiring is good execution that is not directly bottlenecked +* +* The formulas are computed in slots. +* A slot is an entry in the pipeline each for the pipeline width +* (for example a 4-wide pipeline has 4 slots for each cycle) +* +* Formulas: +* BadSpeculation = ((SlotsIssued - SlotsRetired) + RecoveryBubbles) / +* TotalSlots +* Retiring = SlotsRetired / TotalSlots +* FrontendBound = FetchBubbles / TotalSlots +* BackendBound = 1.0 - BadSpeculation - Retiring - FrontendBound +* +* The kernel provides the mapping to the low level CPU events and any scaling +* needed for the CPU pipeline width, for example: +* +* TotalSlots = Cycles * 4 +* +* The scaling factor is communicated in the sysfs unit. +* +* In some cases the CPU may not be able to measure all the formulas due to +* missing events. In this case multiple formulas are combined, as possible. +* +* Full TopDown supports more levels to sub-divide each area: for example +* BackendBound into computing bound and memory bound. For now we only +* support Level 1 TopDown. +*/ + +static double sanitize_val (double x) +{ +if (x <0 && x >=-0.02 ) +return 0.0 ; +return x; +} + +static double td_total_slots (int ctx,int cpu) +{ +return avg_stats (&runtime_topdown_total_slots[ctx][cpu]); +} + +static double td_bad_spec (int ctx,int cpu) +{ +double bad_spec =0 ; +double total_slots; +double total; + + total =avg_stats (&runtime_topdown_slots_issued[ctx][cpu]) - +avg_stats (&runtime_topdown_slots_retired[ctx][cpu]) + +avg_stats (&runtime_topdown_recovery_bubbles[ctx][cpu]); + total_slots =td_total_slots (ctx, cpu); +if (total_slots) + bad_spec = total / total_slots; +return sanitize_val (bad_spec); +} + +static double td_retiring (int ctx,int cpu) +{ +double retiring =0 ; +double total_slots =td_total_slots (ctx, cpu); +double ret_slots =avg_stats (&runtime_topdown_slots_retired[ctx][cpu]); + +if (total_slots) + retiring = ret_slots / total_slots; +return retiring; +} + +static double td_fe_bound (int ctx,int cpu) +{ +double fe_bound =0 ; +double total_slots =td_total_slots (ctx, cpu); +double fetch_bub =avg_stats (&runtime_topdown_fetch_bubbles[ctx][cpu]); + +if (total_slots) + fe_bound = fetch_bub / total_slots; +return fe_bound; +} + +static double td_be_bound (int ctx,int cpu) +{ +double sum = (td_fe_bound (ctx, cpu) + +td_bad_spec (ctx, cpu) + +td_retiring (ctx, cpu)); +if (sum ==0 ) +return 0 ; +return sanitize_val (1.0 - sum); +} +void perf_stat__print_shadow_stats (struct perf_evsel *evsel,double avg,int cpu,struct perf_stat_output_ctx *out)
@@ -309,6 +430,7 @@ void perf_stat__print_shadow_stats(struct perf_evsel *evsel,void *ctxp = out->ctx;print_metric_t print_metric = out->print_metric;double total, ratio =0.0 , total2; +const char *color =NULL ;int ctx =evsel_context (evsel);if (perf_evsel__match (evsel,HARDWARE ,HW_INSTRUCTIONS )) {
@@ -452,6 +574,46 @@ void perf_stat__print_shadow_stats(struct perf_evsel *evsel, avg / ratio); else print_metric(ctxp, NULL, NULL, "CPUs utilized", 0); + } else if (perf_stat_evsel__is(evsel, TOPDOWN_FETCH_BUBBLES)) { +double fe_bound =td_fe_bound (ctx, cpu); + +if (fe_bound >0.2 ) + color =PERF_COLOR_RED ; +print_metric (ctxp, color,"%8.1f%%" ,"frontend bound" , + fe_bound *100. ); + }else if (perf_stat_evsel__is (evsel,TOPDOWN_SLOTS_RETIRED )) { +double retiring =td_retiring (ctx, cpu); + +if (retiring >0.7 ) + color =PERF_COLOR_GREEN ; +print_metric (ctxp, color,"%8.1f%%" ,"retiring" , + retiring *100. ); + }else if (perf_stat_evsel__is (evsel,TOPDOWN_RECOVERY_BUBBLES )) { +double bad_spec =td_bad_spec (ctx, cpu); + +if (bad_spec >0.1 ) + color =PERF_COLOR_RED ; +print_metric (ctxp, color,"%8.1f%%" ,"bad speculation" , + bad_spec *100. ); + }else if (perf_stat_evsel__is (evsel,TOPDOWN_SLOTS_ISSUED )) { +double be_bound =td_be_bound (ctx, cpu); +const char *name ="backend bound" ; +static int have_recovery_bubbles =-1 ; + +/* In case the CPU does not support topdown-recovery-bubbles */ +if (have_recovery_bubbles <0 ) + have_recovery_bubbles =pmu_have_event ("cpu" , +"topdown-recovery-bubbles" ); +if (!have_recovery_bubbles) + name ="backend bound/bad spec" ; + +if (be_bound >0.2 ) + color =PERF_COLOR_RED ; +if (td_total_slots (ctx, cpu) >0 ) +print_metric (ctxp, color,"%8.1f%%" , name, + be_bound *100. ); +else +print_metric (ctxp,NULL ,NULL , name,0 ); }else if (runtime_nsecs_stats[cpu].n !=0 ) {char unit ='M' ;char unit_buf[10 ];
tools/perf/util/stat.c +5 -0
@@ -79,6 +79,11 @@ static const char *id_str[PERF_STAT_EVSEL_ID__MAX] = { ID(TRANSACTION_START, cpu/tx-start/), ID(ELISION_START, cpu/el-start/), ID(CYCLES_IN_TX_CP, cpu/cycles-ct/), +ID (TOPDOWN_TOTAL_SLOTS , topdown-total-slots), +ID (TOPDOWN_SLOTS_ISSUED , topdown-slots-issued), +ID (TOPDOWN_SLOTS_RETIRED , topdown-slots-retired), +ID (TOPDOWN_FETCH_BUBBLES , topdown-fetch-bubbles), + ID(TOPDOWN_RECOVERY_BUBBLES, topdown-recovery-bubbles), };#undef ID
tools/perf/util/stat.h +5 -0
@@ -17,6 +17,11 @@ enum perf_stat_evsel_id {PERF_STAT_EVSEL_ID__TRANSACTION_START ,PERF_STAT_EVSEL_ID__ELISION_START ,PERF_STAT_EVSEL_ID__CYCLES_IN_TX_CP , +PERF_STAT_EVSEL_ID__TOPDOWN_TOTAL_SLOTS , +PERF_STAT_EVSEL_ID__TOPDOWN_SLOTS_ISSUED , +PERF_STAT_EVSEL_ID__TOPDOWN_SLOTS_RETIRED , +PERF_STAT_EVSEL_ID__TOPDOWN_FETCH_BUBBLES , +PERF_STAT_EVSEL_ID__TOPDOWN_RECOVERY_BUBBLES , PERF_STAT_EVSEL_ID__MAX, };
Signature · 1 line
2.5.5
Arnaldo Carvalho de Melo
maintainerPATCH 8/11 perf stat: Print topology/time headers with --metric-only
In reply to Arnaldo Carvalho de MeloFrom: Andi Kleen <[email protected]>
When --metric-only is enabled there were no headers for the topology in interval mode. Also when headers were printed they were on a separate line.
Before:
$ perf stat --metric-only -A -I 1000 -a
1.001038376 frontend cycles idle insn per cycle stalled cycles per insn branch-misses of all branches
1.001038376 CPU0 123.54% 0.23 5.29 7.61%
1.001038376 CPU1 137.78% 0.24 5.13 10.07%
1.001038376 CPU2 64.48% 0.22 5.50 6.84%After:
$ perf stat --metric-only -A -I 1000 -a
1.001111114 CPU0 82.46% 0.32 2.60 7.64%
1.001111114 CPU1 126.63% 0.02 42.83 0.15%
1.001111114 CPU2 193.54% 0.32 2.59 6.92%v2: Move all headers on a single line
--- tools/perf/builtin-stat.c | 32 ++++++++++++++++++++++---------- 1 file changed, 22 insertions(+), 10 deletions(-)
tools/perf/builtin-stat.c +22 -10
@@ -1316,7 +1316,7 @@ static int aggr_header_lens[] = { [AGGR_GLOBAL] = 0, }; -static void print_metric_headers (char *prefix) +static void print_metric_headers (const char *prefix,bool no_indent) {struct perf_stat_output_ctx out;struct perf_evsel *counter;
@@ -1327,7 +1327,7 @@ static void print_metric_headers(char *prefix)if (prefix)fprintf (stat_config.output,"%s" , prefix); -if (!csv_output) +if (!csv_output && !no_indent)fprintf (stat_config.output,"%*s" , aggr_header_lens[stat_config.aggr_mode],"" );
@@ -1352,28 +1352,40 @@ static void print_interval(char *prefix, struct timespec *ts)sprintf (prefix,"%6lu.%09lu%s" , ts->tv_sec, ts->tv_nsec, csv_sep); -if (num_print_interval ==0 && !csv_output && !metric_only) { +if (num_print_interval ==0 && !csv_output) {switch (stat_config.aggr_mode) {case AGGR_SOCKET : -fprintf (output,"# time socket cpus counts %*s events\n" , unit_width,"unit" ); +fprintf (output,"# time socket cpus" ); +if (!metric_only) +fprintf (output," counts %*s events\n" , unit_width,"unit" );break ;case AGGR_CORE : -fprintf (output,"# time core cpus counts %*s events\n" , unit_width,"unit" ); +fprintf (output,"# time core cpus" ); +if (!metric_only) +fprintf (output," counts %*s events\n" , unit_width,"unit" );break ;case AGGR_NONE : -fprintf (output,"# time CPU counts %*s events\n" , unit_width,"unit" ); +fprintf (output,"# time CPU" ); +if (!metric_only) +fprintf (output," counts %*s events\n" , unit_width,"unit" );break ;case AGGR_THREAD : -fprintf (output,"# time comm-pid counts %*s events\n" , unit_width,"unit" ); +fprintf (output,"# time comm-pid" ); +if (!metric_only) +fprintf (output," counts %*s events\n" , unit_width,"unit" );break ;case AGGR_GLOBAL :default : -fprintf (output,"# time counts %*s events\n" , unit_width,"unit" ); +fprintf (output,"# time" ); +if (!metric_only) +fprintf (output," counts %*s events\n" , unit_width,"unit" );case AGGR_UNSET :break ; } } +if (num_print_interval ==0 && metric_only) +print_metric_headers (" " , true);if (++num_print_interval ==25 ) num_print_interval =0 ; }
@@ -1442,8 +1454,8 @@ static void print_counters(struct timespec *ts, int argc, const char **argv)if (metric_only) {static int num_print_iv; -if (num_print_iv ==0 ) -print_metric_headers (prefix); +if (num_print_iv ==0 && !interval) +print_metric_headers (prefix, false);if (num_print_iv++ ==25 ) num_print_iv =0 ;if (stat_config.aggr_mode ==AGGR_GLOBAL && prefix)
Signature · 1 line
2.5.5
Arnaldo Carvalho de Melo
maintainerPATCH 9/11 perf stat: Add missing aggregation headers for --metric-only CSV
In reply to Arnaldo Carvalho de MeloFrom: Andi Kleen <[email protected]>
When in CSV mode --metric-only outputs an header, unlike the other modes. Previously it did not properly print headers for the aggregation columns, so the headers were actually shifted against the real values.
Fix this here by outputting the correct headers for CSV.
v2: Indent array.
--- tools/perf/builtin-stat.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
tools/perf/builtin-stat.c +14 -0
@@ -1316,6 +1316,14 @@ static int aggr_header_lens[] = { [AGGR_GLOBAL] = 0, }; +static const char *aggr_header_csv[] = { + [AGGR_CORE ] ="core,cpus," , + [AGGR_SOCKET ] ="socket,cpus" , + [AGGR_NONE ] ="cpu," , + [AGGR_THREAD ] ="comm-pid," , + [AGGR_GLOBAL ] ="" +}; +static void print_metric_headers (const char *prefix,bool no_indent) {struct perf_stat_output_ctx out;
@@ -1330,6 +1338,12 @@ static void print_metric_headers(const char *prefix, bool no_indent)if (!csv_output && !no_indent)fprintf (stat_config.output,"%*s" , aggr_header_lens[stat_config.aggr_mode],"" ); +if (csv_output) { +if (stat_config.interval) +fputs ("time," , stat_config.output); +fputs (aggr_header_csv[stat_config.aggr_mode], + stat_config.output); + }/* Print metrics headers only */ evlist__for_each (evsel_list, counter) {
Signature · 1 line
2.5.5
Arnaldo Carvalho de Melo
maintainerPATCH 10/11 perf config: Fix abnormal termination at perf_parse_file()
In reply to Arnaldo Carvalho de MeloFrom: Taeung Song <[email protected]>
If a config file has wrong key-value pairs, the perf process will be forcibly terminated by die() at perf_parse_file() called by perf_config() so terminal settings can be crushed because of unusual termination.
For example:
If user config file has a wrong value 'red;default' instead of a normal value like 'red, default' for a key 'colors.top',
# cat ~/.perfconfig
[colors]
medium = red;default # wrong valueand if running sub-command 'top',
# perf top
perf process is dead by force and terminal setting is broken with a messge like below.
Fatal: bad config file line 2 in /root/.perfconfig
So fix it.
If perf_config() can return on failure without calling die() at perf_parse_file(), this problem can be solved.
And if a config file has wrong values, show the error message and then use default config values instead of wrong config values.
--- tools/perf/util/config.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-)
tools/perf/util/config.c +7 -9
@@ -275,7 +275,8 @@ static int perf_parse_file(config_fn_t fn, void *data)break ; } } -die ("bad config file line %d in %s" , config_linenr, config_file_name); +pr_err ("bad config file line %d in %s\n" , config_linenr, config_file_name); +return -1 ; }static int parse_unit_factor (const char *end,unsigned long *val)
@@ -479,16 +480,15 @@ static int perf_config_global(void)int perf_config (config_fn_t fn,void *data) { -int ret =0 , found =0 ; +int ret =-1 ;const char *home =NULL ;/* Setting $PERF_CONFIG makes perf read _only_ the given config file. */ if (config_exclusive_filename)return perf_config_from_file (fn, config_exclusive_filename, data);if (perf_config_system () && !access (perf_etc_perfconfig (),R_OK )) { - ret +=perf_config_from_file (fn,perf_etc_perfconfig (), - data); - found +=1 ; +if (perf_config_from_file (fn,perf_etc_perfconfig (), data) <0 ) + goto out; } home =getenv ("HOME" );
@@ -514,14 +514,12 @@ int perf_config(config_fn_t fn, void *data)if (!st.st_size) goto out_free; - ret +=perf_config_from_file (fn, user_config, data); - found +=1 ; + ret =perf_config_from_file (fn, user_config, data); + out_free:free (user_config); } out: -if (found ==0 ) -return -1 ;return ret; }
Signature · 1 line
2.5.5
Arnaldo Carvalho de Melo
maintainerPATCH 11/11 perf config: Handle the error when config set is NULL at collect_config()
In reply to Arnaldo Carvalho de MeloFrom: Taeung Song <[email protected]>
collect_config() collect all config key-value pairs from config files and put each config info in config set. But if config set (i.e. 'set' variable at collect_config()) is NULL, this is wrong so handle it.
--- tools/perf/util/config.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
tools/perf/util/config.c +5 -1
@@ -607,8 +607,12 @@ static int collect_config(const char *var, const char *value,struct perf_config_section *section =NULL ;struct perf_config_item *item =NULL ;struct perf_config_set *set = perf_config_set; -struct list_head *sections = &set->sections; +struct list_head *sections; +if (set ==NULL ) +return -1 ; + + sections = &set->sections; key = ptr =strdup (var);if (!key) {pr_debug ("%s: strdup failed\n" , __func__);
Signature · 1 line
2.5.5
Quoted 76 lines · Arnaldo Carvalho de Melo
Hi Ingo,
Please consider pulling,
- Arnaldo
The following changes since commit
030ba6cd105c68ce919c5e239853b567490cd059:perf/x86/intel: Use new
topology_max_smt_threads()in HT leak workaround (2016-06-03 09:41:25 +0200)are available in the git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.gittags/perf-core-for-mingo-20160606for you to fetch changes up to
7db91f251056f90fec4121f028680ab3153a0f3c:perf config: Handle the error when config set is NULL at
collect_config()(2016-06-06 17:43:19 -0300)----------------------------------------------------------------
perf/core improvements and fixes:User visible:
- Tooling support for TopDown counters, recently added to the kernel (Andi Kleen)
- Show call graphs in 'perf script' when 1st event doesn't have it but some other has (He Kuang)
- Fix terminal cleanup when handling invalid .perfconfig files in 'perf top' (Taeung Song)
Build fixes:
- Respect
CROSS_COMPILEfor the linker in libapi (Lucas Stach)Infrastructure:
- Fix
perf_evlist__alloc_mmap()failure path (Wang Nan)- Provide way to extract integer value from
format_field(Arnaldo Carvalho de Melo)Signed-off-by Arnaldo Carvalho de Melo <[email protected]>----------------------------------------------------------------
Andi Kleen (5):
perf test: Ignore .scale and other special files
perf stat: Basic support for TopDown in perf stat perf stat: Add computation of TopDown formulas
perf stat: Print topology/time headers with --metric-only perf stat: Add missing aggregation headers for --metric-only CSVArnaldo Carvalho de Melo (1):
perf evsel: Provide way to extract integer value fromformat_fieldHe Kuang (1):
perf script: Show call graphs when 1st event doesn't have it but some other hasLucas Stach (1):
tools lib api: RespectCROSS_COMPILEfor the linkerTaeung Song (2):
perf config: Fix abnormal termination atperf_parse_file()perf config: Handle the error when config set is NULL atcollect_config()Wang Nan (1):
perf evlist: Fixalloc_mmap()failure pathtools/lib/api/Makefile | 1 + tools/perf/Documentation/perf-stat.txt | 32 +++++++ tools/perf/arch/x86/util/Build | 1 + tools/perf/arch/x86/util/group.c | 27 ++++++ tools/perf/builtin-script.c | 23 +++-- tools/perf/builtin-stat.c | 165 ++++++++++++++++++++++++++++++--- tools/perf/tests/parse-events.c | 4 +- tools/perf/util/config.c | 22 +++-- tools/perf/util/evlist.c | 5 +- tools/perf/util/evsel.c | 25 +++-- tools/perf/util/evsel.h | 2 +
Quoted 8 lines
tools/perf/util/group.h | 7 ++ tools/perf/util/parse-events.l | 1 + tools/perf/util/stat-shadow.c | 162 ++++++++++++++++++++++++++++++++ tools/perf/util/stat.c | 5 + tools/perf/util/stat.h | 5 + 16 files changed, 441 insertions(+), 46 deletions(-) create mode 100644 tools/perf/arch/x86/util/group.c create mode 100644 tools/perf/util/group.h
Pulled, thanks a lot Arnaldo!
Ingo