17a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt#ifndef _LINUX_RING_BUFFER_H 27a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt#define _LINUX_RING_BUFFER_H 37a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 41744a21d57d9c60136461adb6afa85e51b3e94d9Vegard Nossum#include <linux/kmemcheck.h> 57a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt#include <linux/mm.h> 67a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt#include <linux/seq_file.h> 77a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 87a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtstruct ring_buffer; 97a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtstruct ring_buffer_iter; 107a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 117a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt/* 12c3706f005c3aaf570e71f0f083fdbb59a5a9fa2eWenji Huang * Don't refer to this struct directly, use functions below. 137a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt */ 147a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtstruct ring_buffer_event { 151744a21d57d9c60136461adb6afa85e51b3e94d9Vegard Nossum kmemcheck_bitfield_begin(bitfield); 16334d4169a6592d3fcd863bbe822a8f6985ffa9afLai Jiangshan u32 type_len:5, time_delta:27; 171744a21d57d9c60136461adb6afa85e51b3e94d9Vegard Nossum kmemcheck_bitfield_end(bitfield); 181744a21d57d9c60136461adb6afa85e51b3e94d9Vegard Nossum 197a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt u32 array[]; 207a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt}; 217a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 227a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt/** 237a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt * enum ring_buffer_type - internal ring buffer types 247a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt * 252d622719f1572ef31e0616444a515eba3094d050Tom Zanussi * @RINGBUF_TYPE_PADDING: Left over page padding or discarded event 262d622719f1572ef31e0616444a515eba3094d050Tom Zanussi * If time_delta is 0: 272d622719f1572ef31e0616444a515eba3094d050Tom Zanussi * array is ignored 282d622719f1572ef31e0616444a515eba3094d050Tom Zanussi * size is variable depending on how much 297a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt * padding is needed 302d622719f1572ef31e0616444a515eba3094d050Tom Zanussi * If time_delta is non zero: 31334d4169a6592d3fcd863bbe822a8f6985ffa9afLai Jiangshan * array[0] holds the actual length 32334d4169a6592d3fcd863bbe822a8f6985ffa9afLai Jiangshan * size = 4 + length (bytes) 337a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt * 347a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt * @RINGBUF_TYPE_TIME_EXTEND: Extend the time delta 357a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt * array[0] = time delta (28 .. 59) 367a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt * size = 8 bytes 377a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt * 387a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt * @RINGBUF_TYPE_TIME_STAMP: Sync time stamp with external clock 39361b73d5c34f59c3fd107bb9dbe7a1fbff2c2517Lai Jiangshan * array[0] = tv_nsec 40361b73d5c34f59c3fd107bb9dbe7a1fbff2c2517Lai Jiangshan * array[1..2] = tv_sec 417a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt * size = 16 bytes 427a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt * 43334d4169a6592d3fcd863bbe822a8f6985ffa9afLai Jiangshan * <= @RINGBUF_TYPE_DATA_TYPE_LEN_MAX: 44334d4169a6592d3fcd863bbe822a8f6985ffa9afLai Jiangshan * Data record 45334d4169a6592d3fcd863bbe822a8f6985ffa9afLai Jiangshan * If type_len is zero: 467a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt * array[0] holds the actual length 47361b73d5c34f59c3fd107bb9dbe7a1fbff2c2517Lai Jiangshan * array[1..(length+3)/4] holds data 48334d4169a6592d3fcd863bbe822a8f6985ffa9afLai Jiangshan * size = 4 + length (bytes) 497a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt * else 50334d4169a6592d3fcd863bbe822a8f6985ffa9afLai Jiangshan * length = type_len << 2 51361b73d5c34f59c3fd107bb9dbe7a1fbff2c2517Lai Jiangshan * array[0..(length+3)/4-1] holds data 52361b73d5c34f59c3fd107bb9dbe7a1fbff2c2517Lai Jiangshan * size = 4 + length (bytes) 537a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt */ 547a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtenum ring_buffer_type { 55334d4169a6592d3fcd863bbe822a8f6985ffa9afLai Jiangshan RINGBUF_TYPE_DATA_TYPE_LEN_MAX = 28, 567a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt RINGBUF_TYPE_PADDING, 577a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt RINGBUF_TYPE_TIME_EXTEND, 587a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt /* FIXME: RINGBUF_TYPE_TIME_STAMP not implemented */ 597a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt RINGBUF_TYPE_TIME_STAMP, 607a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt}; 617a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 627a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtunsigned ring_buffer_event_length(struct ring_buffer_event *event); 637a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtvoid *ring_buffer_event_data(struct ring_buffer_event *event); 647a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 65fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedt/* 66fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedt * ring_buffer_discard_commit will remove an event that has not 67fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedt * ben committed yet. If this is used, then ring_buffer_unlock_commit 68fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedt * must not be called on the discarded event. This function 69fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedt * will try to remove the event from the ring buffer completely 70fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedt * if another event has not been written after it. 71fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedt * 72fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedt * Example use: 73fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedt * 74fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedt * if (some_condition) 75fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedt * ring_buffer_discard_commit(buffer, event); 76fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedt * else 77fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedt * ring_buffer_unlock_commit(buffer, event); 78fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedt */ 79fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedtvoid ring_buffer_discard_commit(struct ring_buffer *buffer, 80fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedt struct ring_buffer_event *event); 81fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedt 82fa1b47dd85453ec7d4bcfe4aa4a2d172ba452fc3Steven Rostedt/* 837a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt * size is in bytes for each per CPU buffer. 847a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt */ 857a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtstruct ring_buffer * 861f8a6a10fb9437eac3f516ea4324a19087872f30Peter Zijlstra__ring_buffer_alloc(unsigned long size, unsigned flags, struct lock_class_key *key); 871f8a6a10fb9437eac3f516ea4324a19087872f30Peter Zijlstra 881f8a6a10fb9437eac3f516ea4324a19087872f30Peter Zijlstra/* 891f8a6a10fb9437eac3f516ea4324a19087872f30Peter Zijlstra * Because the ring buffer is generic, if other users of the ring buffer get 901f8a6a10fb9437eac3f516ea4324a19087872f30Peter Zijlstra * traced by ftrace, it can produce lockdep warnings. We need to keep each 911f8a6a10fb9437eac3f516ea4324a19087872f30Peter Zijlstra * ring buffer's lock class separate. 921f8a6a10fb9437eac3f516ea4324a19087872f30Peter Zijlstra */ 931f8a6a10fb9437eac3f516ea4324a19087872f30Peter Zijlstra#define ring_buffer_alloc(size, flags) \ 941f8a6a10fb9437eac3f516ea4324a19087872f30Peter Zijlstra({ \ 951f8a6a10fb9437eac3f516ea4324a19087872f30Peter Zijlstra static struct lock_class_key __key; \ 961f8a6a10fb9437eac3f516ea4324a19087872f30Peter Zijlstra __ring_buffer_alloc((size), (flags), &__key); \ 971f8a6a10fb9437eac3f516ea4324a19087872f30Peter Zijlstra}) 981f8a6a10fb9437eac3f516ea4324a19087872f30Peter Zijlstra 997a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtvoid ring_buffer_free(struct ring_buffer *buffer); 1007a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 1017a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtint ring_buffer_resize(struct ring_buffer *buffer, unsigned long size); 1027a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 103750912fa366312e9c5bc83eab352898a26750401David Sharpvoid ring_buffer_change_overwrite(struct ring_buffer *buffer, int val); 104750912fa366312e9c5bc83eab352898a26750401David Sharp 1050a9877514c4fed10a70720293b37213dd172ee3eArnaldo Carvalho de Melostruct ring_buffer_event *ring_buffer_lock_reserve(struct ring_buffer *buffer, 1060a9877514c4fed10a70720293b37213dd172ee3eArnaldo Carvalho de Melo unsigned long length); 1077a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtint ring_buffer_unlock_commit(struct ring_buffer *buffer, 1080a9877514c4fed10a70720293b37213dd172ee3eArnaldo Carvalho de Melo struct ring_buffer_event *event); 1097a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtint ring_buffer_write(struct ring_buffer *buffer, 1107a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt unsigned long length, void *data); 1117a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 1127a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtstruct ring_buffer_event * 11366a8cb95ed04025664d1db4e952155ee1dccd048Steven Rostedtring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts, 11466a8cb95ed04025664d1db4e952155ee1dccd048Steven Rostedt unsigned long *lost_events); 1157a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtstruct ring_buffer_event * 11666a8cb95ed04025664d1db4e952155ee1dccd048Steven Rostedtring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts, 11766a8cb95ed04025664d1db4e952155ee1dccd048Steven Rostedt unsigned long *lost_events); 1187a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 1197a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtstruct ring_buffer_iter * 12072c9ddfd4c5bf54ef03cfdf57026416cb678eebaDavid Millerring_buffer_read_prepare(struct ring_buffer *buffer, int cpu); 12172c9ddfd4c5bf54ef03cfdf57026416cb678eebaDavid Millervoid ring_buffer_read_prepare_sync(void); 12272c9ddfd4c5bf54ef03cfdf57026416cb678eebaDavid Millervoid ring_buffer_read_start(struct ring_buffer_iter *iter); 1237a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtvoid ring_buffer_read_finish(struct ring_buffer_iter *iter); 1247a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 1257a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtstruct ring_buffer_event * 1267a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtring_buffer_iter_peek(struct ring_buffer_iter *iter, u64 *ts); 1277a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtstruct ring_buffer_event * 1287a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtring_buffer_read(struct ring_buffer_iter *iter, u64 *ts); 1297a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtvoid ring_buffer_iter_reset(struct ring_buffer_iter *iter); 1307a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtint ring_buffer_iter_empty(struct ring_buffer_iter *iter); 1317a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 1327a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtunsigned long ring_buffer_size(struct ring_buffer *buffer); 1337a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 1347a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtvoid ring_buffer_reset_cpu(struct ring_buffer *buffer, int cpu); 1357a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtvoid ring_buffer_reset(struct ring_buffer *buffer); 1367a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 13785bac32c4a52c592b857f2c360cc5ec93a097d70Steven Rostedt#ifdef CONFIG_RING_BUFFER_ALLOW_SWAP 1387a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtint ring_buffer_swap_cpu(struct ring_buffer *buffer_a, 1397a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt struct ring_buffer *buffer_b, int cpu); 14085bac32c4a52c592b857f2c360cc5ec93a097d70Steven Rostedt#else 14185bac32c4a52c592b857f2c360cc5ec93a097d70Steven Rostedtstatic inline int 14285bac32c4a52c592b857f2c360cc5ec93a097d70Steven Rostedtring_buffer_swap_cpu(struct ring_buffer *buffer_a, 14385bac32c4a52c592b857f2c360cc5ec93a097d70Steven Rostedt struct ring_buffer *buffer_b, int cpu) 14485bac32c4a52c592b857f2c360cc5ec93a097d70Steven Rostedt{ 14585bac32c4a52c592b857f2c360cc5ec93a097d70Steven Rostedt return -ENODEV; 14685bac32c4a52c592b857f2c360cc5ec93a097d70Steven Rostedt} 14785bac32c4a52c592b857f2c360cc5ec93a097d70Steven Rostedt#endif 1487a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 1497a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtint ring_buffer_empty(struct ring_buffer *buffer); 1507a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtint ring_buffer_empty_cpu(struct ring_buffer *buffer, int cpu); 1517a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 1527a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtvoid ring_buffer_record_disable(struct ring_buffer *buffer); 1537a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtvoid ring_buffer_record_enable(struct ring_buffer *buffer); 154499e547057f5bba5cd6f87ebe59b05d0c59da905Steven Rostedtvoid ring_buffer_record_off(struct ring_buffer *buffer); 155499e547057f5bba5cd6f87ebe59b05d0c59da905Steven Rostedtvoid ring_buffer_record_on(struct ring_buffer *buffer); 156499e547057f5bba5cd6f87ebe59b05d0c59da905Steven Rostedtint ring_buffer_record_is_on(struct ring_buffer *buffer); 1577a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtvoid ring_buffer_record_disable_cpu(struct ring_buffer *buffer, int cpu); 1587a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtvoid ring_buffer_record_enable_cpu(struct ring_buffer *buffer, int cpu); 1597a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 160c64e148a3be3cb786534ad38298c25c833116c26Vaibhav Nagarnaikunsigned long ring_buffer_oldest_event_ts(struct ring_buffer *buffer, int cpu); 161c64e148a3be3cb786534ad38298c25c833116c26Vaibhav Nagarnaikunsigned long ring_buffer_bytes_cpu(struct ring_buffer *buffer, int cpu); 1627a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtunsigned long ring_buffer_entries(struct ring_buffer *buffer); 1637a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtunsigned long ring_buffer_overruns(struct ring_buffer *buffer); 164e09373f22e76cc048ca5fe10a9ff9012f5d64309Robert Richterunsigned long ring_buffer_entries_cpu(struct ring_buffer *buffer, int cpu); 165e09373f22e76cc048ca5fe10a9ff9012f5d64309Robert Richterunsigned long ring_buffer_overrun_cpu(struct ring_buffer *buffer, int cpu); 166f0d2c681ac0a85142fc8abe65fc33fcad35cb9b7Steven Rostedtunsigned long ring_buffer_commit_overrun_cpu(struct ring_buffer *buffer, int cpu); 1677a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 16837886f6a9f62d22530ffee8d3f9215c8345b6969Steven Rostedtu64 ring_buffer_time_stamp(struct ring_buffer *buffer, int cpu); 16937886f6a9f62d22530ffee8d3f9215c8345b6969Steven Rostedtvoid ring_buffer_normalize_time_stamp(struct ring_buffer *buffer, 17037886f6a9f62d22530ffee8d3f9215c8345b6969Steven Rostedt int cpu, u64 *ts); 17137886f6a9f62d22530ffee8d3f9215c8345b6969Steven Rostedtvoid ring_buffer_set_clock(struct ring_buffer *buffer, 17237886f6a9f62d22530ffee8d3f9215c8345b6969Steven Rostedt u64 (*clock)(void)); 1737a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 174ef7a4a161472b952941bf78855a9cd95703c024eSteven Rostedtsize_t ring_buffer_page_len(void *page); 175ef7a4a161472b952941bf78855a9cd95703c024eSteven Rostedt 176ef7a4a161472b952941bf78855a9cd95703c024eSteven Rostedt 1777ea5906405a1f3fc1c0033dfd7e02f2cfd1de5e5Vaibhav Nagarnaikvoid *ring_buffer_alloc_read_page(struct ring_buffer *buffer, int cpu); 1788789a9e7df6bf9b93739c4c7d4e380725bc9e936Steven Rostedtvoid ring_buffer_free_read_page(struct ring_buffer *buffer, void *data); 179ef7a4a161472b952941bf78855a9cd95703c024eSteven Rostedtint ring_buffer_read_page(struct ring_buffer *buffer, void **data_page, 180ef7a4a161472b952941bf78855a9cd95703c024eSteven Rostedt size_t len, int cpu, int full); 1818789a9e7df6bf9b93739c4c7d4e380725bc9e936Steven Rostedt 182d1b182a8d49ed6416325b4e0a1cb0f17cd4e702aSteven Rostedtstruct trace_seq; 183d1b182a8d49ed6416325b4e0a1cb0f17cd4e702aSteven Rostedt 184d1b182a8d49ed6416325b4e0a1cb0f17cd4e702aSteven Rostedtint ring_buffer_print_entry_header(struct trace_seq *s); 185d1b182a8d49ed6416325b4e0a1cb0f17cd4e702aSteven Rostedtint ring_buffer_print_page_header(struct trace_seq *s); 186d1b182a8d49ed6416325b4e0a1cb0f17cd4e702aSteven Rostedt 1877a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedtenum ring_buffer_flags { 1887a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt RB_FL_OVERWRITE = 1 << 0, 1897a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt}; 1907a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt 1917a8e76a3829f1067b70f715771ff88baf2fbf3c3Steven Rostedt#endif /* _LINUX_RING_BUFFER_H */ 192