Hi Namhyung, On 1/4/23 07:17, Namhyung Kim wrote:
Add missing perf_event_attr fields, new event codes and sample type. Also add descriptions for PERF_FORMAT_LOST. Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
Thanks for the revised patch! Please see some minor comments below. Cheers, Alex
--- man2/perf_event_open.2 | 200 ++++++++++++++++++++++++++++++++++++++--- 1 file changed, 190 insertions(+), 10 deletions(-) diff --git a/man2/perf_event_open.2 b/man2/perf_event_open.2 index 8e94fb4ac..2cf673f3d 100644 --- a/man2/perf_event_open.2 +++ b/man2/perf_event_open.2 @@ -245,8 +245,15 @@ struct perf_event_attr { instead of events */ cgroup : 1, /* include cgroup events */ text_poke : 1, /* include text poke events */ + build_id : 1, /* use build id in mmap2 events */ + inherit_thread : 1, /* children only inherit */ + /* if cloned with CLONE_THREAD */ + remove_on_exec : 1, /* event is removed from task + on exec */ + sigtrap : 1, /* send synchronous SIGTRAP + on event */- __reserved_1 : 30;+ __reserved_1 : 26;union {__u32 wakeup_events; /* wakeup every n events */ @@ -277,6 +284,9 @@ struct perf_event_attr { __u32 aux_watermark; /* aux bytes before wakeup */ __u16 sample_max_stack; /* max frames in callchain */ __u16 __reserved_2; /* align to u64 */ + __u32 aux_sample_size; /* max aux sample size */ + __u32 __reserved_3; /* align to u64 */ + __u64 sig_data; /* user data for sigtrap */};.EE @@ -538,6 +548,19 @@ Informational sample record types such as mmap or comm must be associated with an active event. This dummy event allows gathering such records without requiring a counting event. +.TP +.BR PERF_COUNT_SW_BPF_OUTPUT " (since Linux 4.4)" +.\" commit a43eec304259a6c637f4014a6d4767159b6a3aa3 +This is used to generate raw sample data from BPF. +BPF programs can write to this event using +.B bpf_perf_event_output +helper. +.TP +.BR PERF_COUNT_SW_CGROUP_SWITCHES " (since Linux 5.13)" +.\" commit d0d1dd628527c77db2391ce0293c1ed344b2365f +This counts context switches to a task in a different cgroup. +In other words, if the next task is in the same cgroup, +it won't count the switch. .RE .PP .RS @@ -879,6 +902,41 @@ This corresponds to the field in the .B PERF_RECORD_CGROUP event. +.TP +.BR PERF_SAMPLE_DATA_PAGE_SIZE " (since Linux 5.11)" +.\" commit 8d97e71811aaafe4abf611dc24822fd6e73df1a1 +Records page size of data like in +.BR PERF_SAMPLE_ADDR . +.TP +.BR PERF_SAMPLE_CODE_PAGE_SIZE " (since Linux 5.11)" +.\" commit 995f088efebe1eba0282a6ffa12411b37f8990c2 +Records page size of ip like in +.BR PERF_SAMPLE_IP . +.TP +.BR PERF_SAMPLE_WEIGHT_STRUCT " (since Linux 5.12)" +.\" commit 2a6c6b7d7ad346f0679d0963cb19b3f0ea7ef32c +Records hardware provided weight values like in +.BR PERF_SAMPLE_WEIGHT , +but it can represent multiple values in a struct. +This shares the same space as the +.BR PERF_SAMPLE_WEIGHT , +so users can apply either of those, not the both. +When used, it would have the following format and +the meaning of each fields is dependent to the +hardware implementation. +.PP +.in +4n +.EX +union perf_sample_weight { + u64 full; /* PERF_SAMPLE_WEIGHT */ + struct { /* PERF_SAMPLE_WEIGHT_STRUCT */ + u32 var1_dw; + u16 var2_w; + u16 var3_w; + }; +}; +.EE +.in .RE .TP .I read_format @@ -908,6 +966,15 @@ Adds a 64-bit unique value that corresponds to the event group. .TP .B PERF_FORMAT_GROUP Allows all counter values in an event group to be read with one read. +.TP +.B PERF_FORMAT_LOST " (since Linux 6.0)" +.\" commit 119a784c81270eb88e573174ed2209225d646656 +Adds a 64-bit value that is the number of lost samples for this event. +This would be only meaningful when +.I sample_period +or +.I sample_freq +is set. .RE .TP .I disabled @@ -1243,7 +1310,7 @@ This enables the generation of .B PERF_RECORD_BPF_EVENT records when an eBPF program is loaded or unloaded. .TP -.IR auxevent " (since Linux 5.4)" +.IR aux_output " (since Linux 5.4)" .\" commit ab43762ef010967e4ccd53627f70a2eecbeafefb This allows normal (non-AUX) events to generate data for AUX events if the hardware supports it. @@ -1261,6 +1328,31 @@ This enables the generation of records when there's a change to the kernel text (i.e., self-modifying code). .TP +.IR build_id " (since Linux 5.12)" +.\" commit 88a16a1309333e43d328621ece3e9fa37027e8eb +This changes the contents in the +.B PERF_RECORD_MMAP2 +to have a build-id instead of device and inode numbers. +.TP +.IR inherit_thread " (since Linux 5.13)" +.\" commit 2b26f0aa004995f49f7b6f4100dd0e4c39a9ed5f +This disables the inheritance of the event to a child process. +Only new threads in the same process (which is cloned with +.BR CLONE_THREAD ) +will inherit the event. +.TP +.IR remove_on_exec " (since Linux 5.13)" +.\" commit 2e498d0a74e5b88a6689ae1b811f247f91ff188e +This closes the event when it starts a new process image by +.BR execve (2) +system call. +.TP +.IR sigtrap " (since Linux 5.13)" +.\" commit 97ba62b278674293762c3d91f724f1bb922f04e0 +This enables synchronous signal delivery of +.B SIGTRAP +on event overflow. +.TP .IR wakeup_events ", " wakeup_watermark This union sets how many samples .RI ( wakeup_events ) @@ -1471,6 +1563,21 @@ includes .BR PERF_SAMPLE_CALLCHAIN , this field specifies how many stack frames to report when generating the callchain. +.TP +.IR aux_sample_size " (since Linux 5.5)" +.\" commit a4faf00d994c40e64f656805ac375c65e324eefb +When +.B PERF_SAMPLE_AUX +flag is set, specify the desired size of AUX data. +Note that it can get smaller data than the specified size. +.TP +.IR sig_data " (since Linux 5.13)" +.\" commit 97ba62b278674293762c3d91f724f1bb922f04e0 +This data will be copied to user's signal handler (through +.I si_perf +in the +.IR siginfo_t ) +to disambiguate which event triggered the signal. .SS Reading results Once a .BR perf_event_open () @@ -1502,6 +1609,7 @@ struct read_format { struct { u64 value; /* The value of the event */ u64 id; /* if PERF_FORMAT_ID */ + u64 lost; /* if PERF_FORMAT_LOST */ } values[nr]; }; .EE @@ -1520,6 +1628,7 @@ struct read_format { u64 time_enabled; /* if PERF_FORMAT_TOTAL_TIME_ENABLED */ u64 time_running; /* if PERF_FORMAT_TOTAL_TIME_RUNNING */ u64 id; /* if PERF_FORMAT_ID */ + u64 lost; /* if PERF_FORMAT_LOST */ }; .EE .in @@ -1551,6 +1660,12 @@ A globally unique value for this particular event; only present if .B PERF_FORMAT_ID was specified in .IR read_format . +.TP +.I lost +The number of lost samples of this event; only present if +.B PERF_FORMAT_LOST +was specified in +.IR read_format . .SS MMAP layout When using .BR perf_event_open () @@ -2002,6 +2117,22 @@ to the actual instruction that triggered the event. See also .IR perf_event_attr.precise_ip . .TP +.BR PERF_RECORD_MISC_SWITCH_OUT_PREEMPT " (since Linux 4.17)" +.\" commit 101592b4904ecf6b8ed2a4784d41d180319d95a1 +When a +.B PERF_RECORD_SWITCH +or +.B PERF_RECORD_SWITCH_CPU_WIDE +record is generated, this indicates the context switch +was a preemption. +.TP +.BR PERF_RECORD_MISC_MMAP_BUILD_ID " (since Linux 5.12)" +.\" commit 88a16a1309333e43d328621ece3e9fa37027e8eb +This indicates that the content of +.B PERF_SAMPLE_MMAP2 +contains build-ID data instead of device major and minor numbers +as well as the inode number. +.TP .BR PERF_RECORD_MISC_EXT_RESERVED " (since Linux 2.6.35)" .\" commit 1676b8a077c352085d52578fb4f29350b58b6e74 This indicates there is extended data available (currently not used). @@ -2201,7 +2332,9 @@ struct { char data[size]; /* if PERF_SAMPLE_STACK_USER */ u64 dyn_size; /* if PERF_SAMPLE_STACK_USER && size != 0 */ - u64 weight; /* if PERF_SAMPLE_WEIGHT */ + union perf_sample_weight; + /* if PERF_SAMPLE_WEIGHT */ + /* || PERF_SAMPLE_WEIGHT_STRUCT */ u64 data_src; /* if PERF_SAMPLE_DATA_SRC */ u64 transaction; /* if PERF_SAMPLE_TRANSACTION */ u64 abi; /* if PERF_SAMPLE_REGS_INTR */ @@ -2209,6 +2342,12 @@ struct { /* if PERF_SAMPLE_REGS_INTR */ u64 phys_addr; /* if PERF_SAMPLE_PHYS_ADDR */ u64 cgroup; /* if PERF_SAMPLE_CGROUP */ + u64 data_page_size; + /* if PERF_SAMPLE_DATA_PAGE_SIZE */ + u64 code_page_size; + /* if PERF_SAMPLE_CODE_PAGE_SIZE */ + u64 size; /* if PERF_SAMPLE_AUX */ + char data[size]; /* if PERF_SAMPLE_AUX */ }; .EE .in @@ -2410,7 +2549,7 @@ is 0. .TP .I weight If -.B PERF_SAMPLE_WEIGHT +.B PERF_SAMPLE_WEIGHT "or" PERF_SAMPLE_WEIGHT_STRUCT
These should go in separate lines (otherwise, whitespaces are missing): .B FOO or .B BAR
is enabled, then a 64-bit value provided by the hardware is recorded that indicates how costly the event was. This allows expensive events to stand out more clearly @@ -2643,7 +2782,28 @@ If the flag is set, then the 64-bit cgroup ID (for the perf_event subsystem) is recorded. To get the pathname of the cgroup, the ID should match to one in a -.B PERF_RECORD_CGROUP . +.BR PERF_RECORD_CGROUP . +.TP +.I data_page_size +If the +.B PERF_SAMPLE_DATA_PAGE_SIZE +flag is set, +then the 64-bit page size value of the +.B data +address is recorded. +.TP +.I code_page_size +If the +.B PERF_SAMPLE_CODE_PAGE_SIZE +flag is set, +then the 64-bit page size value of the +.B ip +address is recorded. +.TP +.IR size ", " data[size]
I prefer having them in separate lines (I know the current page already has that ugly stuff, but I'd rather write new stuff properly):
.TP .I size .TQ .IR data [ size ] TQ is a continuation tag for TP.
+If +.B PERF_SAMPLE_AUX +is enabled, then a snapshot of the aux buffer is recorded. .RE .TP .B PERF_RECORD_MMAP2 @@ -2653,7 +2813,9 @@ calls returning executable mappings. The format is similar to that of the .B PERF_RECORD_MMAP record, but includes extra values that allow uniquely identifying -shared mappings. +shared mappings. Depending on the
Please _always_ break lines after a period (and usually also after a comma; and before an opening parenthesis, or after a closing one). But for periods it's a rather hard rule.
+.B PERF_RECORD_MISC_MMAP_BUILD_ID
+bit in the header, the extra values have different layout and meanings.
.IP
.in +4n
.EX
@@ -2664,10 +2826,20 @@ struct {
u64 addr;
u64 len;
u64 pgoff;
- u32 maj;
- u32 min;
- u64 ino;
- u64 ino_generation;
+ union {
+ struct {
+ u32 maj;
+ u32 min;
+ u64 ino;
+ u64 ino_generation;
+ };
+ struct { /* if PERF_RECORD_MISC_MMAP_BUILD_ID */
+ u8 build_id_size;
+ u8 __reserved_1;
+ u16 __reserved_2;
+ u8 build_id[20];
+ };
+ };
u32 prot;
u32 flags;
char filename[];
@@ -2704,6 +2876,14 @@ is the inode number.
.I ino_generation
is the inode generation.
.TP
+.I build_id_size
+is the actual size of
+.I build_id
+field (up to 20).
+.TP
+.I build_id
+is a raw data to identify a binary.
+.TP
.I prot
is the protection information.
.TP
-- <http://www.alejandro-colomar.es/>
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