diff options
author | Ingo Molnar <mingo@elte.hu> | 2010-02-08 08:55:43 +0100 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2010-02-08 08:55:46 +0100 |
commit | 6d3e0907b8b239d16720d144e2675ecf10d3bc3b (patch) | |
tree | e0b0743b5f6f82b057cafc4f3687396a6e01a0b4 /tools | |
parent | 23577256953c870de9b724c3a2611ce7be6a1e4e (diff) | |
parent | 50200df462023b187d80a99a52f5f2cfe3c86c26 (diff) | |
download | talos-obmc-linux-6d3e0907b8b239d16720d144e2675ecf10d3bc3b.tar.gz talos-obmc-linux-6d3e0907b8b239d16720d144e2675ecf10d3bc3b.zip |
Merge branch 'sched/urgent' into sched/core
Merge reason: Merge dependent fix, update to latest -rc.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'tools')
-rw-r--r-- | tools/perf/.gitignore | 1 | ||||
-rw-r--r-- | tools/perf/Makefile | 52 | ||||
-rw-r--r-- | tools/perf/builtin-buildid-list.c | 2 | ||||
-rw-r--r-- | tools/perf/builtin-diff.c | 3 | ||||
-rw-r--r-- | tools/perf/builtin-kmem.c | 11 | ||||
-rw-r--r-- | tools/perf/builtin-record.c | 14 | ||||
-rw-r--r-- | tools/perf/builtin-report.c | 5 | ||||
-rw-r--r-- | tools/perf/builtin-timechart.c | 2 | ||||
-rw-r--r-- | tools/perf/builtin-trace.c | 4 | ||||
-rw-r--r-- | tools/perf/design.txt | 8 |
10 files changed, 63 insertions, 39 deletions
diff --git a/tools/perf/.gitignore b/tools/perf/.gitignore index fe08660ce0bd..124760bb37b5 100644 --- a/tools/perf/.gitignore +++ b/tools/perf/.gitignore @@ -13,6 +13,7 @@ perf*.xml perf*.html common-cmds.h perf.data +perf.data.old tags TAGS cscope* diff --git a/tools/perf/Makefile b/tools/perf/Makefile index 4390d225686d..2e7fa3a06806 100644 --- a/tools/perf/Makefile +++ b/tools/perf/Makefile @@ -250,7 +250,19 @@ PTHREAD_LIBS = -lpthread # explicitly what architecture to check for. Fix this up for yours.. SPARSE_FLAGS = -D__BIG_ENDIAN__ -D__powerpc__ -ifeq ($(shell sh -c "echo 'int foo(void) {char X[2]; return 3;}' | $(CC) -x c -c -Werror -fstack-protector-all - -o /dev/null "$(QUIET_STDERR)" && echo y"), y) +ifeq ($(V), 2) + QUIET_STDERR = ">/dev/null" +else + QUIET_STDERR = ">/dev/null 2>&1" +endif + +BITBUCKET = "/dev/null" + +ifneq ($(shell sh -c "(echo '\#include <stdio.h>'; echo 'int main(void) { return puts(\"hi\"); }') | $(CC) -x c - $(ALL_CFLAGS) -o $(BITBUCKET) "$(QUIET_STDERR)" && echo y"), y) + BITBUCKET = .perf.dev.null +endif + +ifeq ($(shell sh -c "echo 'int foo(void) {char X[2]; return 3;}' | $(CC) -x c -c -Werror -fstack-protector-all - -o $(BITBUCKET) "$(QUIET_STDERR)" && echo y"), y) CFLAGS := $(CFLAGS) -fstack-protector-all endif @@ -343,13 +355,18 @@ LIB_H += util/include/linux/string.h LIB_H += util/include/linux/types.h LIB_H += util/include/asm/asm-offsets.h LIB_H += util/include/asm/bitops.h +LIB_H += util/include/asm/bug.h LIB_H += util/include/asm/byteorder.h LIB_H += util/include/asm/swab.h LIB_H += util/include/asm/system.h LIB_H += util/include/asm/uaccess.h LIB_H += perf.h +LIB_H += util/cache.h +LIB_H += util/callchain.h +LIB_H += util/debug.h LIB_H += util/debugfs.h LIB_H += util/event.h +LIB_H += util/exec_cmd.h LIB_H += util/types.h LIB_H += util/levenshtein.h LIB_H += util/parse-options.h @@ -362,6 +379,7 @@ LIB_H += util/session.h LIB_H += util/strbuf.h LIB_H += util/string.h LIB_H += util/strlist.h +LIB_H += util/svghelper.h LIB_H += util/run-command.h LIB_H += util/sigchain.h LIB_H += util/symbol.h @@ -370,6 +388,8 @@ LIB_H += util/values.h LIB_H += util/sort.h LIB_H += util/hist.h LIB_H += util/thread.h +LIB_H += util/trace-event.h +LIB_H += util/trace-event-perl.h LIB_H += util/probe-finder.h LIB_H += util/probe-event.h @@ -443,11 +463,6 @@ BUILTIN_OBJS += builtin-kmem.o PERFLIBS = $(LIB_FILE) -ifeq ($(V), 2) - QUIET_STDERR = ">/dev/null" -else - QUIET_STDERR = ">/dev/null 2>&1" -endif # # Platform specific tweaks # @@ -475,19 +490,19 @@ ifeq ($(uname_S),Darwin) PTHREAD_LIBS = endif -ifeq ($(shell sh -c "(echo '\#include <libelf.h>'; echo 'int main(void) { Elf * elf = elf_begin(0, ELF_C_READ, 0); return (long)elf; }') | $(CC) -x c - $(ALL_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -o /dev/null $(ALL_LDFLAGS) $(EXTLIBS) "$(QUIET_STDERR)" && echo y"), y) -ifneq ($(shell sh -c "(echo '\#include <gnu/libc-version.h>'; echo 'int main(void) { const char * version = gnu_get_libc_version(); return (long)version; }') | $(CC) -x c - $(ALL_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -o /dev/null $(ALL_LDFLAGS) $(EXTLIBS) "$(QUIET_STDERR)" && echo y"), y) +ifeq ($(shell sh -c "(echo '\#include <libelf.h>'; echo 'int main(void) { Elf * elf = elf_begin(0, ELF_C_READ, 0); return (long)elf; }') | $(CC) -x c - $(ALL_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) "$(QUIET_STDERR)" && echo y"), y) +ifneq ($(shell sh -c "(echo '\#include <gnu/libc-version.h>'; echo 'int main(void) { const char * version = gnu_get_libc_version(); return (long)version; }') | $(CC) -x c - $(ALL_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) "$(QUIET_STDERR)" && echo y"), y) msg := $(error No gnu/libc-version.h found, please install glibc-dev[el]/glibc-static); endif - ifneq ($(shell sh -c "(echo '\#include <libelf.h>'; echo 'int main(void) { Elf * elf = elf_begin(0, ELF_C_READ_MMAP, 0); return (long)elf; }') | $(CC) -x c - $(ALL_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -o /dev/null $(ALL_LDFLAGS) $(EXTLIBS) "$(QUIET_STDERR)" && echo y"), y) + ifneq ($(shell sh -c "(echo '\#include <libelf.h>'; echo 'int main(void) { Elf * elf = elf_begin(0, ELF_C_READ_MMAP, 0); return (long)elf; }') | $(CC) -x c - $(ALL_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) "$(QUIET_STDERR)" && echo y"), y) BASIC_CFLAGS += -DLIBELF_NO_MMAP endif else msg := $(error No libelf.h/libelf found, please install libelf-dev/elfutils-libelf-devel and glibc-dev[el]); endif -ifneq ($(shell sh -c "(echo '\#ifndef _MIPS_SZLONG'; echo '\#define _MIPS_SZLONG 0'; echo '\#endif'; echo '\#include <dwarf.h>'; echo '\#include <libdwarf.h>'; echo 'int main(void) { Dwarf_Debug dbg; Dwarf_Error err; Dwarf_Ranges *rng; dwarf_init(0, DW_DLC_READ, 0, 0, &dbg, &err); dwarf_get_ranges(dbg, 0, &rng, 0, 0, &err); return (long)dbg; }') | $(CC) -x c - $(ALL_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -I/usr/include/libdwarf -ldwarf -lelf -o /dev/null $(ALL_LDFLAGS) $(EXTLIBS) "$(QUIET_STDERR)" && echo y"), y) +ifneq ($(shell sh -c "(echo '\#ifndef _MIPS_SZLONG'; echo '\#define _MIPS_SZLONG 0'; echo '\#endif'; echo '\#include <dwarf.h>'; echo '\#include <libdwarf.h>'; echo 'int main(void) { Dwarf_Debug dbg; Dwarf_Error err; Dwarf_Ranges *rng; dwarf_init(0, DW_DLC_READ, 0, 0, &dbg, &err); dwarf_get_ranges(dbg, 0, &rng, 0, 0, &err); return (long)dbg; }') | $(CC) -x c - $(ALL_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -I/usr/include/libdwarf -ldwarf -lelf -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) "$(QUIET_STDERR)" && echo y"), y) msg := $(warning No libdwarf.h found or old libdwarf.h found, disables dwarf support. Please install libdwarf-dev/libdwarf-devel >= 20081231); BASIC_CFLAGS += -DNO_LIBDWARF else @@ -501,7 +516,7 @@ PERL_EMBED_LDOPTS = `perl -MExtUtils::Embed -e ldopts 2>/dev/null` PERL_EMBED_CCOPTS = `perl -MExtUtils::Embed -e ccopts 2>/dev/null` endif -ifneq ($(shell sh -c "(echo '\#include <EXTERN.h>'; echo '\#include <perl.h>'; echo 'int main(void) { perl_alloc(); return 0; }') | $(CC) -x c - $(PERL_EMBED_CCOPTS) -o /dev/null $(PERL_EMBED_LDOPTS) > /dev/null 2>&1 && echo y"), y) +ifneq ($(shell sh -c "(echo '\#include <EXTERN.h>'; echo '\#include <perl.h>'; echo 'int main(void) { perl_alloc(); return 0; }') | $(CC) -x c - $(PERL_EMBED_CCOPTS) -o $(BITBUCKET) $(PERL_EMBED_LDOPTS) > /dev/null 2>&1 && echo y"), y) BASIC_CFLAGS += -DNO_LIBPERL else ALL_LDFLAGS += $(PERL_EMBED_LDOPTS) @@ -511,20 +526,20 @@ endif ifdef NO_DEMANGLE BASIC_CFLAGS += -DNO_DEMANGLE else - has_bfd := $(shell sh -c "(echo '\#include <bfd.h>'; echo 'int main(void) { bfd_demangle(0, 0, 0); return 0; }') | $(CC) -x c - $(ALL_CFLAGS) -o /dev/null $(ALL_LDFLAGS) $(EXTLIBS) -lbfd "$(QUIET_STDERR)" && echo y") + has_bfd := $(shell sh -c "(echo '\#include <bfd.h>'; echo 'int main(void) { bfd_demangle(0, 0, 0); return 0; }') | $(CC) -x c - $(ALL_CFLAGS) -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) -lbfd "$(QUIET_STDERR)" && echo y") ifeq ($(has_bfd),y) EXTLIBS += -lbfd else - has_bfd_iberty := $(shell sh -c "(echo '\#include <bfd.h>'; echo 'int main(void) { bfd_demangle(0, 0, 0); return 0; }') | $(CC) -x c - $(ALL_CFLAGS) -o /dev/null $(ALL_LDFLAGS) $(EXTLIBS) -lbfd -liberty "$(QUIET_STDERR)" && echo y") + has_bfd_iberty := $(shell sh -c "(echo '\#include <bfd.h>'; echo 'int main(void) { bfd_demangle(0, 0, 0); return 0; }') | $(CC) -x c - $(ALL_CFLAGS) -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) -lbfd -liberty "$(QUIET_STDERR)" && echo y") ifeq ($(has_bfd_iberty),y) EXTLIBS += -lbfd -liberty else - has_bfd_iberty_z := $(shell sh -c "(echo '\#include <bfd.h>'; echo 'int main(void) { bfd_demangle(0, 0, 0); return 0; }') | $(CC) -x c - $(ALL_CFLAGS) -o /dev/null $(ALL_LDFLAGS) $(EXTLIBS) -lbfd -liberty -lz "$(QUIET_STDERR)" && echo y") + has_bfd_iberty_z := $(shell sh -c "(echo '\#include <bfd.h>'; echo 'int main(void) { bfd_demangle(0, 0, 0); return 0; }') | $(CC) -x c - $(ALL_CFLAGS) -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) -lbfd -liberty -lz "$(QUIET_STDERR)" && echo y") ifeq ($(has_bfd_iberty_z),y) EXTLIBS += -lbfd -liberty -lz else - has_cplus_demangle := $(shell sh -c "(echo 'extern char *cplus_demangle(const char *, int);'; echo 'int main(void) { cplus_demangle(0, 0); return 0; }') | $(CC) -x c - $(ALL_CFLAGS) -o /dev/null $(ALL_LDFLAGS) $(EXTLIBS) -liberty "$(QUIET_STDERR)" && echo y") + has_cplus_demangle := $(shell sh -c "(echo 'extern char *cplus_demangle(const char *, int);'; echo 'int main(void) { cplus_demangle(0, 0); return 0; }') | $(CC) -x c - $(ALL_CFLAGS) -o $(BITBUCKET) $(ALL_LDFLAGS) $(EXTLIBS) -liberty "$(QUIET_STDERR)" && echo y") ifeq ($(has_cplus_demangle),y) EXTLIBS += -liberty BASIC_CFLAGS += -DHAVE_CPLUS_DEMANGLE @@ -772,7 +787,7 @@ export TAR INSTALL DESTDIR SHELL_PATH SHELL = $(SHELL_PATH) -all:: shell_compatibility_test $(ALL_PROGRAMS) $(BUILT_INS) $(OTHER_PROGRAMS) PERF-BUILD-OPTIONS +all:: .perf.dev.null shell_compatibility_test $(ALL_PROGRAMS) $(BUILT_INS) $(OTHER_PROGRAMS) PERF-BUILD-OPTIONS ifneq (,$X) $(foreach p,$(patsubst %$X,%,$(filter %$X,$(ALL_PROGRAMS) $(BUILT_INS) perf$X)), test '$p' -ef '$p$X' || $(RM) '$p';) endif @@ -1099,6 +1114,11 @@ clean: .PHONY: .FORCE-PERF-VERSION-FILE TAGS tags cscope .FORCE-PERF-CFLAGS .PHONY: .FORCE-PERF-BUILD-OPTIONS +.perf.dev.null: + touch .perf.dev.null + +.INTERMEDIATE: .perf.dev.null + ### Make sure built-ins do not have dups and listed in perf.c # check-builtins:: diff --git a/tools/perf/builtin-buildid-list.c b/tools/perf/builtin-buildid-list.c index e693e6777af5..1e99ac806913 100644 --- a/tools/perf/builtin-buildid-list.c +++ b/tools/perf/builtin-buildid-list.c @@ -17,7 +17,7 @@ static char const *input_name = "perf.data"; static int force; -static const char *const buildid_list_usage[] = { +static const char * const buildid_list_usage[] = { "perf buildid-list [<options>]", NULL }; diff --git a/tools/perf/builtin-diff.c b/tools/perf/builtin-diff.c index 4d33b55d5584..bd71b8ceafb7 100644 --- a/tools/perf/builtin-diff.c +++ b/tools/perf/builtin-diff.c @@ -189,8 +189,9 @@ out_delete: return ret; } -static const char *const diff_usage[] = { +static const char * const diff_usage[] = { "perf diff [<options>] [old_file] [new_file]", + NULL, }; static const struct option options[] = { diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c index fc21ad79dd83..93c67bf53d2c 100644 --- a/tools/perf/builtin-kmem.c +++ b/tools/perf/builtin-kmem.c @@ -137,7 +137,7 @@ static void insert_alloc_stat(unsigned long call_site, unsigned long ptr, if (data && data->ptr == ptr) { data->hit++; data->bytes_req += bytes_req; - data->bytes_alloc += bytes_req; + data->bytes_alloc += bytes_alloc; } else { data = malloc(sizeof(*data)); if (!data) @@ -177,7 +177,7 @@ static void insert_caller_stat(unsigned long call_site, if (data && data->call_site == call_site) { data->hit++; data->bytes_req += bytes_req; - data->bytes_alloc += bytes_req; + data->bytes_alloc += bytes_alloc; } else { data = malloc(sizeof(*data)); if (!data) @@ -375,7 +375,7 @@ static void __print_result(struct rb_root *root, struct perf_session *session, printf("%.102s\n", graph_dotted_line); printf(" %-34s |", is_caller ? "Callsite": "Alloc Ptr"); - printf(" Total_alloc/Per | Total_req/Per | Hit | Ping-pong | Frag\n"); + printf(" Total_alloc/Per | Total_req/Per | Hit | Ping-pong | Frag\n"); printf("%.102s\n", graph_dotted_line); next = rb_first(root); @@ -401,7 +401,7 @@ static void __print_result(struct rb_root *root, struct perf_session *session, snprintf(buf, sizeof(buf), "%#Lx", addr); printf(" %-34s |", buf); - printf(" %9llu/%-5lu | %9llu/%-5lu | %6lu | %8lu | %6.3f%%\n", + printf(" %9llu/%-5lu | %9llu/%-5lu | %8lu | %8lu | %6.3f%%\n", (unsigned long long)data->bytes_alloc, (unsigned long)data->bytes_alloc / data->hit, (unsigned long long)data->bytes_req, @@ -784,7 +784,8 @@ int cmd_kmem(int argc, const char **argv, const char *prefix __used) setup_sorting(&alloc_sort, default_sort_order); return __cmd_kmem(); - } + } else + usage_with_options(kmem_usage, kmem_options); return 0; } diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 63136d0534d4..265425322734 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -402,7 +402,7 @@ static void atexit_header(void) perf_header__write(&session->header, output, true); } -static int __cmd_record(int argc __used, const char **argv) +static int __cmd_record(int argc, const char **argv) { int i, counter; struct stat st; @@ -411,6 +411,7 @@ static int __cmd_record(int argc __used, const char **argv) int err; unsigned long waking = 0; int child_ready_pipe[2], go_pipe[2]; + const bool forks = target_pid == -1 && argc > 0; char buf; page_size = sysconf(_SC_PAGE_SIZE); @@ -422,7 +423,7 @@ static int __cmd_record(int argc __used, const char **argv) signal(SIGCHLD, sig_handler); signal(SIGINT, sig_handler); - if (pipe(child_ready_pipe) < 0 || pipe(go_pipe) < 0) { + if (forks && (pipe(child_ready_pipe) < 0 || pipe(go_pipe) < 0)) { perror("failed to create pipes"); exit(-1); } @@ -483,7 +484,7 @@ static int __cmd_record(int argc __used, const char **argv) atexit(atexit_header); - if (target_pid == -1) { + if (forks) { pid = fork(); if (pid < 0) { perror("failed to fork"); @@ -550,7 +551,7 @@ static int __cmd_record(int argc __used, const char **argv) return err; } - if (!system_wide) + if (!system_wide && profile_cpu == -1) event__synthesize_thread(pid, process_synthesized_event, session); else @@ -569,7 +570,8 @@ static int __cmd_record(int argc __used, const char **argv) /* * Let the child rip */ - close(go_pipe[1]); + if (forks) + close(go_pipe[1]); for (;;) { int hits = samples; @@ -667,7 +669,7 @@ int cmd_record(int argc, const char **argv, const char *prefix __used) argc = parse_options(argc, argv, options, record_usage, PARSE_OPT_STOP_AT_NON_OPTION); - if (!argc && target_pid == -1 && (!system_wide || profile_cpu == -1)) + if (!argc && target_pid == -1 && !system_wide && profile_cpu == -1) usage_with_options(record_usage, options); symbol__init(); diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c index 5c2ab5357ec6..860f1eeeea7d 100644 --- a/tools/perf/builtin-report.c +++ b/tools/perf/builtin-report.c @@ -269,7 +269,7 @@ parse_callchain_opt(const struct option *opt __used, const char *arg, else if (!strncmp(tok, "none", strlen(arg))) { callchain_param.mode = CHAIN_NONE; - symbol_conf.use_callchain = true; + symbol_conf.use_callchain = false; return 0; } @@ -294,8 +294,7 @@ setup: return 0; } -//static const char * const report_usage[] = { -const char * const report_usage[] = { +static const char * const report_usage[] = { "perf report [<options>] <command>", NULL }; diff --git a/tools/perf/builtin-timechart.c b/tools/perf/builtin-timechart.c index a589a43112d6..3f8bbcfb1e9b 100644 --- a/tools/perf/builtin-timechart.c +++ b/tools/perf/builtin-timechart.c @@ -280,7 +280,7 @@ static u64 cpus_pstate_state[MAX_CPUS]; static int process_comm_event(event_t *event, struct perf_session *session __used) { - pid_set_comm(event->comm.pid, event->comm.comm); + pid_set_comm(event->comm.tid, event->comm.comm); return 0; } diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index e2285e28720f..574a215e800b 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -512,7 +512,7 @@ static char *get_script_path(const char *script_root, const char *suffix) return path; } -static const char * const annotate_usage[] = { +static const char * const trace_usage[] = { "perf trace [<options>] <command>", NULL }; @@ -581,7 +581,7 @@ int cmd_trace(int argc, const char **argv, const char *prefix __used) setup_scripting(); - argc = parse_options(argc, argv, options, annotate_usage, + argc = parse_options(argc, argv, options, trace_usage, PARSE_OPT_STOP_AT_NON_OPTION); if (symbol__init() < 0) diff --git a/tools/perf/design.txt b/tools/perf/design.txt index f000c30877ac..8d0de5130db3 100644 --- a/tools/perf/design.txt +++ b/tools/perf/design.txt @@ -21,7 +21,7 @@ There's one file descriptor per virtual counter used. The special file descriptor is opened via the perf_event_open() system call: - int sys_perf_event_open(struct perf_event_hw_event *hw_event_uptr, + int sys_perf_event_open(struct perf_event_attr *hw_event_uptr, pid_t pid, int cpu, int group_fd, unsigned long flags); @@ -32,9 +32,9 @@ can be used to set the blocking mode, etc. Multiple counters can be kept open at a time, and the counters can be poll()ed. -When creating a new counter fd, 'perf_event_hw_event' is: +When creating a new counter fd, 'perf_event_attr' is: -struct perf_event_hw_event { +struct perf_event_attr { /* * The MSB of the config word signifies if the rest contains cpu * specific (raw) counter configuration data, if unset, the next @@ -399,7 +399,7 @@ Notification of new events is possible through poll()/select()/epoll() and fcntl() managing signals. Normally a notification is generated for every page filled, however one can -additionally set perf_event_hw_event.wakeup_events to generate one every +additionally set perf_event_attr.wakeup_events to generate one every so many counter overflow events. Future work will include a splice() interface to the ring-buffer. |