linux_dsm_epyc7002/tools/perf/util/ordered-events.c

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 21:07:57 +07:00
// SPDX-License-Identifier: GPL-2.0
#include <errno.h>
#include <inttypes.h>
#include <linux/list.h>
#include <linux/compiler.h>
perf session: Add option to copy events when queueing When processing events the session code has an ordered samples queue which is used to time-sort events coming in across multiple mmaps. At a later point in time samples on the queue are flushed up to some timestamp at which point the event is actually processed. When analyzing events live (ie., record/analysis path in the same command) there is a race that leads to corrupted events and parse errors which cause perf to terminate. The problem is that when the event is placed in the ordered samples queue it is only a reference to the event which is really sitting in the mmap buffer. Even though the event is queued for later processing the mmap tail pointer is updated which indicates to the kernel that the event has been processed. The race is flushing the event from the queue before it gets overwritten by some other event. For commands trying to process events live (versus just writing to a file) and processing a high rate of events this leads to parse failures and perf terminates. Examples hitting this problem are 'perf kvm stat live', especially with nested VMs which generate 100,000+ traces per second, and a command processing scheduling events with a high rate of context switching -- e.g., running 'perf bench sched pipe'. This patch offers live commands an option to copy the event when it is placed in the ordered samples queue. Based on a patch from David Ahern <dsahern@gmail.com> Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1412347212-28237-2-git-send-email-yarygin@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-10-03 21:40:11 +07:00
#include <linux/string.h>
#include "ordered-events.h"
#include "session.h"
#include "asm/bug.h"
#include "debug.h"
#define pr_N(n, fmt, ...) \
eprintf(n, debug_ordered_events, fmt, ##__VA_ARGS__)
#define pr(fmt, ...) pr_N(1, pr_fmt(fmt), ##__VA_ARGS__)
static void queue_event(struct ordered_events *oe, struct ordered_event *new)
{
struct ordered_event *last = oe->last;
u64 timestamp = new->timestamp;
struct list_head *p;
++oe->nr_events;
oe->last = new;
pr_oe_time2(timestamp, "queue_event nr_events %u\n", oe->nr_events);
if (!last) {
list_add(&new->list, &oe->events);
oe->max_timestamp = timestamp;
return;
}
/*
* last event might point to some random place in the list as it's
* the last queued event. We expect that the new event is close to
* this.
*/
if (last->timestamp <= timestamp) {
while (last->timestamp <= timestamp) {
p = last->list.next;
if (p == &oe->events) {
list_add_tail(&new->list, &oe->events);
oe->max_timestamp = timestamp;
return;
}
last = list_entry(p, struct ordered_event, list);
}
list_add_tail(&new->list, &last->list);
} else {
while (last->timestamp > timestamp) {
p = last->list.prev;
if (p == &oe->events) {
list_add(&new->list, &oe->events);
return;
}
last = list_entry(p, struct ordered_event, list);
}
list_add(&new->list, &last->list);
}
}
perf session: Add option to copy events when queueing When processing events the session code has an ordered samples queue which is used to time-sort events coming in across multiple mmaps. At a later point in time samples on the queue are flushed up to some timestamp at which point the event is actually processed. When analyzing events live (ie., record/analysis path in the same command) there is a race that leads to corrupted events and parse errors which cause perf to terminate. The problem is that when the event is placed in the ordered samples queue it is only a reference to the event which is really sitting in the mmap buffer. Even though the event is queued for later processing the mmap tail pointer is updated which indicates to the kernel that the event has been processed. The race is flushing the event from the queue before it gets overwritten by some other event. For commands trying to process events live (versus just writing to a file) and processing a high rate of events this leads to parse failures and perf terminates. Examples hitting this problem are 'perf kvm stat live', especially with nested VMs which generate 100,000+ traces per second, and a command processing scheduling events with a high rate of context switching -- e.g., running 'perf bench sched pipe'. This patch offers live commands an option to copy the event when it is placed in the ordered samples queue. Based on a patch from David Ahern <dsahern@gmail.com> Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1412347212-28237-2-git-send-email-yarygin@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-10-03 21:40:11 +07:00
static union perf_event *__dup_event(struct ordered_events *oe,
union perf_event *event)
{
union perf_event *new_event = NULL;
if (oe->cur_alloc_size < oe->max_alloc_size) {
new_event = memdup(event, event->header.size);
if (new_event)
oe->cur_alloc_size += event->header.size;
}
return new_event;
}
static union perf_event *dup_event(struct ordered_events *oe,
union perf_event *event)
{
return oe->copy_on_queue ? __dup_event(oe, event) : event;
}
static void __free_dup_event(struct ordered_events *oe, union perf_event *event)
perf session: Add option to copy events when queueing When processing events the session code has an ordered samples queue which is used to time-sort events coming in across multiple mmaps. At a later point in time samples on the queue are flushed up to some timestamp at which point the event is actually processed. When analyzing events live (ie., record/analysis path in the same command) there is a race that leads to corrupted events and parse errors which cause perf to terminate. The problem is that when the event is placed in the ordered samples queue it is only a reference to the event which is really sitting in the mmap buffer. Even though the event is queued for later processing the mmap tail pointer is updated which indicates to the kernel that the event has been processed. The race is flushing the event from the queue before it gets overwritten by some other event. For commands trying to process events live (versus just writing to a file) and processing a high rate of events this leads to parse failures and perf terminates. Examples hitting this problem are 'perf kvm stat live', especially with nested VMs which generate 100,000+ traces per second, and a command processing scheduling events with a high rate of context switching -- e.g., running 'perf bench sched pipe'. This patch offers live commands an option to copy the event when it is placed in the ordered samples queue. Based on a patch from David Ahern <dsahern@gmail.com> Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1412347212-28237-2-git-send-email-yarygin@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-10-03 21:40:11 +07:00
{
if (event) {
perf session: Add option to copy events when queueing When processing events the session code has an ordered samples queue which is used to time-sort events coming in across multiple mmaps. At a later point in time samples on the queue are flushed up to some timestamp at which point the event is actually processed. When analyzing events live (ie., record/analysis path in the same command) there is a race that leads to corrupted events and parse errors which cause perf to terminate. The problem is that when the event is placed in the ordered samples queue it is only a reference to the event which is really sitting in the mmap buffer. Even though the event is queued for later processing the mmap tail pointer is updated which indicates to the kernel that the event has been processed. The race is flushing the event from the queue before it gets overwritten by some other event. For commands trying to process events live (versus just writing to a file) and processing a high rate of events this leads to parse failures and perf terminates. Examples hitting this problem are 'perf kvm stat live', especially with nested VMs which generate 100,000+ traces per second, and a command processing scheduling events with a high rate of context switching -- e.g., running 'perf bench sched pipe'. This patch offers live commands an option to copy the event when it is placed in the ordered samples queue. Based on a patch from David Ahern <dsahern@gmail.com> Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1412347212-28237-2-git-send-email-yarygin@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-10-03 21:40:11 +07:00
oe->cur_alloc_size -= event->header.size;
free(event);
}
}
static void free_dup_event(struct ordered_events *oe, union perf_event *event)
{
if (oe->copy_on_queue)
__free_dup_event(oe, event);
}
#define MAX_SAMPLE_BUFFER (64 * 1024 / sizeof(struct ordered_event))
perf session: Add option to copy events when queueing When processing events the session code has an ordered samples queue which is used to time-sort events coming in across multiple mmaps. At a later point in time samples on the queue are flushed up to some timestamp at which point the event is actually processed. When analyzing events live (ie., record/analysis path in the same command) there is a race that leads to corrupted events and parse errors which cause perf to terminate. The problem is that when the event is placed in the ordered samples queue it is only a reference to the event which is really sitting in the mmap buffer. Even though the event is queued for later processing the mmap tail pointer is updated which indicates to the kernel that the event has been processed. The race is flushing the event from the queue before it gets overwritten by some other event. For commands trying to process events live (versus just writing to a file) and processing a high rate of events this leads to parse failures and perf terminates. Examples hitting this problem are 'perf kvm stat live', especially with nested VMs which generate 100,000+ traces per second, and a command processing scheduling events with a high rate of context switching -- e.g., running 'perf bench sched pipe'. This patch offers live commands an option to copy the event when it is placed in the ordered samples queue. Based on a patch from David Ahern <dsahern@gmail.com> Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1412347212-28237-2-git-send-email-yarygin@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-10-03 21:40:11 +07:00
static struct ordered_event *alloc_event(struct ordered_events *oe,
union perf_event *event)
{
struct list_head *cache = &oe->cache;
struct ordered_event *new = NULL;
perf session: Add option to copy events when queueing When processing events the session code has an ordered samples queue which is used to time-sort events coming in across multiple mmaps. At a later point in time samples on the queue are flushed up to some timestamp at which point the event is actually processed. When analyzing events live (ie., record/analysis path in the same command) there is a race that leads to corrupted events and parse errors which cause perf to terminate. The problem is that when the event is placed in the ordered samples queue it is only a reference to the event which is really sitting in the mmap buffer. Even though the event is queued for later processing the mmap tail pointer is updated which indicates to the kernel that the event has been processed. The race is flushing the event from the queue before it gets overwritten by some other event. For commands trying to process events live (versus just writing to a file) and processing a high rate of events this leads to parse failures and perf terminates. Examples hitting this problem are 'perf kvm stat live', especially with nested VMs which generate 100,000+ traces per second, and a command processing scheduling events with a high rate of context switching -- e.g., running 'perf bench sched pipe'. This patch offers live commands an option to copy the event when it is placed in the ordered samples queue. Based on a patch from David Ahern <dsahern@gmail.com> Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1412347212-28237-2-git-send-email-yarygin@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-10-03 21:40:11 +07:00
union perf_event *new_event;
size_t size;
perf session: Add option to copy events when queueing When processing events the session code has an ordered samples queue which is used to time-sort events coming in across multiple mmaps. At a later point in time samples on the queue are flushed up to some timestamp at which point the event is actually processed. When analyzing events live (ie., record/analysis path in the same command) there is a race that leads to corrupted events and parse errors which cause perf to terminate. The problem is that when the event is placed in the ordered samples queue it is only a reference to the event which is really sitting in the mmap buffer. Even though the event is queued for later processing the mmap tail pointer is updated which indicates to the kernel that the event has been processed. The race is flushing the event from the queue before it gets overwritten by some other event. For commands trying to process events live (versus just writing to a file) and processing a high rate of events this leads to parse failures and perf terminates. Examples hitting this problem are 'perf kvm stat live', especially with nested VMs which generate 100,000+ traces per second, and a command processing scheduling events with a high rate of context switching -- e.g., running 'perf bench sched pipe'. This patch offers live commands an option to copy the event when it is placed in the ordered samples queue. Based on a patch from David Ahern <dsahern@gmail.com> Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1412347212-28237-2-git-send-email-yarygin@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-10-03 21:40:11 +07:00
new_event = dup_event(oe, event);
if (!new_event)
return NULL;
/*
* We maintain the following scheme of buffers for ordered
* event allocation:
*
* to_free list -> buffer1 (64K)
* buffer2 (64K)
* ...
*
* Each buffer keeps an array of ordered events objects:
* buffer -> event[0]
* event[1]
* ...
*
* Each allocated ordered event is linked to one of
* following lists:
* - time ordered list 'events'
* - list of currently removed events 'cache'
*
* Allocation of the ordered event uses the following order
* to get the memory:
* - use recently removed object from 'cache' list
* - use available object in current allocation buffer
* - allocate new buffer if the current buffer is full
*
* Removal of ordered event object moves it from events to
* the cache list.
*/
size = sizeof(*oe->buffer) + MAX_SAMPLE_BUFFER * sizeof(*new);
if (!list_empty(cache)) {
new = list_entry(cache->next, struct ordered_event, list);
list_del(&new->list);
} else if (oe->buffer) {
new = &oe->buffer->event[oe->buffer_idx];
if (++oe->buffer_idx == MAX_SAMPLE_BUFFER)
oe->buffer = NULL;
} else if ((oe->cur_alloc_size + size) < oe->max_alloc_size) {
oe->buffer = malloc(size);
perf session: Add option to copy events when queueing When processing events the session code has an ordered samples queue which is used to time-sort events coming in across multiple mmaps. At a later point in time samples on the queue are flushed up to some timestamp at which point the event is actually processed. When analyzing events live (ie., record/analysis path in the same command) there is a race that leads to corrupted events and parse errors which cause perf to terminate. The problem is that when the event is placed in the ordered samples queue it is only a reference to the event which is really sitting in the mmap buffer. Even though the event is queued for later processing the mmap tail pointer is updated which indicates to the kernel that the event has been processed. The race is flushing the event from the queue before it gets overwritten by some other event. For commands trying to process events live (versus just writing to a file) and processing a high rate of events this leads to parse failures and perf terminates. Examples hitting this problem are 'perf kvm stat live', especially with nested VMs which generate 100,000+ traces per second, and a command processing scheduling events with a high rate of context switching -- e.g., running 'perf bench sched pipe'. This patch offers live commands an option to copy the event when it is placed in the ordered samples queue. Based on a patch from David Ahern <dsahern@gmail.com> Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1412347212-28237-2-git-send-email-yarygin@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-10-03 21:40:11 +07:00
if (!oe->buffer) {
free_dup_event(oe, new_event);
return NULL;
perf session: Add option to copy events when queueing When processing events the session code has an ordered samples queue which is used to time-sort events coming in across multiple mmaps. At a later point in time samples on the queue are flushed up to some timestamp at which point the event is actually processed. When analyzing events live (ie., record/analysis path in the same command) there is a race that leads to corrupted events and parse errors which cause perf to terminate. The problem is that when the event is placed in the ordered samples queue it is only a reference to the event which is really sitting in the mmap buffer. Even though the event is queued for later processing the mmap tail pointer is updated which indicates to the kernel that the event has been processed. The race is flushing the event from the queue before it gets overwritten by some other event. For commands trying to process events live (versus just writing to a file) and processing a high rate of events this leads to parse failures and perf terminates. Examples hitting this problem are 'perf kvm stat live', especially with nested VMs which generate 100,000+ traces per second, and a command processing scheduling events with a high rate of context switching -- e.g., running 'perf bench sched pipe'. This patch offers live commands an option to copy the event when it is placed in the ordered samples queue. Based on a patch from David Ahern <dsahern@gmail.com> Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1412347212-28237-2-git-send-email-yarygin@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-10-03 21:40:11 +07:00
}
pr("alloc size %" PRIu64 "B (+%zu), max %" PRIu64 "B\n",
oe->cur_alloc_size, size, oe->max_alloc_size);
oe->cur_alloc_size += size;
list_add(&oe->buffer->list, &oe->to_free);
oe->buffer_idx = 1;
new = &oe->buffer->event[0];
} else {
pr("allocation limit reached %" PRIu64 "B\n", oe->max_alloc_size);
return NULL;
}
perf session: Add option to copy events when queueing When processing events the session code has an ordered samples queue which is used to time-sort events coming in across multiple mmaps. At a later point in time samples on the queue are flushed up to some timestamp at which point the event is actually processed. When analyzing events live (ie., record/analysis path in the same command) there is a race that leads to corrupted events and parse errors which cause perf to terminate. The problem is that when the event is placed in the ordered samples queue it is only a reference to the event which is really sitting in the mmap buffer. Even though the event is queued for later processing the mmap tail pointer is updated which indicates to the kernel that the event has been processed. The race is flushing the event from the queue before it gets overwritten by some other event. For commands trying to process events live (versus just writing to a file) and processing a high rate of events this leads to parse failures and perf terminates. Examples hitting this problem are 'perf kvm stat live', especially with nested VMs which generate 100,000+ traces per second, and a command processing scheduling events with a high rate of context switching -- e.g., running 'perf bench sched pipe'. This patch offers live commands an option to copy the event when it is placed in the ordered samples queue. Based on a patch from David Ahern <dsahern@gmail.com> Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1412347212-28237-2-git-send-email-yarygin@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-10-03 21:40:11 +07:00
new->event = new_event;
return new;
}
static struct ordered_event *
ordered_events__new_event(struct ordered_events *oe, u64 timestamp,
perf session: Add option to copy events when queueing When processing events the session code has an ordered samples queue which is used to time-sort events coming in across multiple mmaps. At a later point in time samples on the queue are flushed up to some timestamp at which point the event is actually processed. When analyzing events live (ie., record/analysis path in the same command) there is a race that leads to corrupted events and parse errors which cause perf to terminate. The problem is that when the event is placed in the ordered samples queue it is only a reference to the event which is really sitting in the mmap buffer. Even though the event is queued for later processing the mmap tail pointer is updated which indicates to the kernel that the event has been processed. The race is flushing the event from the queue before it gets overwritten by some other event. For commands trying to process events live (versus just writing to a file) and processing a high rate of events this leads to parse failures and perf terminates. Examples hitting this problem are 'perf kvm stat live', especially with nested VMs which generate 100,000+ traces per second, and a command processing scheduling events with a high rate of context switching -- e.g., running 'perf bench sched pipe'. This patch offers live commands an option to copy the event when it is placed in the ordered samples queue. Based on a patch from David Ahern <dsahern@gmail.com> Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1412347212-28237-2-git-send-email-yarygin@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-10-03 21:40:11 +07:00
union perf_event *event)
{
struct ordered_event *new;
perf session: Add option to copy events when queueing When processing events the session code has an ordered samples queue which is used to time-sort events coming in across multiple mmaps. At a later point in time samples on the queue are flushed up to some timestamp at which point the event is actually processed. When analyzing events live (ie., record/analysis path in the same command) there is a race that leads to corrupted events and parse errors which cause perf to terminate. The problem is that when the event is placed in the ordered samples queue it is only a reference to the event which is really sitting in the mmap buffer. Even though the event is queued for later processing the mmap tail pointer is updated which indicates to the kernel that the event has been processed. The race is flushing the event from the queue before it gets overwritten by some other event. For commands trying to process events live (versus just writing to a file) and processing a high rate of events this leads to parse failures and perf terminates. Examples hitting this problem are 'perf kvm stat live', especially with nested VMs which generate 100,000+ traces per second, and a command processing scheduling events with a high rate of context switching -- e.g., running 'perf bench sched pipe'. This patch offers live commands an option to copy the event when it is placed in the ordered samples queue. Based on a patch from David Ahern <dsahern@gmail.com> Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1412347212-28237-2-git-send-email-yarygin@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-10-03 21:40:11 +07:00
new = alloc_event(oe, event);
if (new) {
new->timestamp = timestamp;
queue_event(oe, new);
}
return new;
}
void ordered_events__delete(struct ordered_events *oe, struct ordered_event *event)
{
list_move(&event->list, &oe->cache);
oe->nr_events--;
perf session: Add option to copy events when queueing When processing events the session code has an ordered samples queue which is used to time-sort events coming in across multiple mmaps. At a later point in time samples on the queue are flushed up to some timestamp at which point the event is actually processed. When analyzing events live (ie., record/analysis path in the same command) there is a race that leads to corrupted events and parse errors which cause perf to terminate. The problem is that when the event is placed in the ordered samples queue it is only a reference to the event which is really sitting in the mmap buffer. Even though the event is queued for later processing the mmap tail pointer is updated which indicates to the kernel that the event has been processed. The race is flushing the event from the queue before it gets overwritten by some other event. For commands trying to process events live (versus just writing to a file) and processing a high rate of events this leads to parse failures and perf terminates. Examples hitting this problem are 'perf kvm stat live', especially with nested VMs which generate 100,000+ traces per second, and a command processing scheduling events with a high rate of context switching -- e.g., running 'perf bench sched pipe'. This patch offers live commands an option to copy the event when it is placed in the ordered samples queue. Based on a patch from David Ahern <dsahern@gmail.com> Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1412347212-28237-2-git-send-email-yarygin@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-10-03 21:40:11 +07:00
free_dup_event(oe, event->event);
perf inject: Copy events when reordering events in pipe mode __perf_session__process_pipe_events reuses the same memory buffer to process all events in the pipe. When reordering is needed (e.g. -b option), events are not immediately flushed, but kept around until reordering is possible, causing memory corruption. The problem is usually observed by a "Unknown sample error" output. It can easily be reproduced by: perf record -o - noploop | perf inject -b > output Committer testing: Before: $ perf record -o - stress -t 2 -c 2 | perf inject -b > /dev/null stress: info: [8297] dispatching hogs: 2 cpu, 0 io, 0 vm, 0 hdd stress: info: [8297] successful run completed in 2s [ perf record: Woken up 3 times to write data ] [ perf record: Captured and wrote 0.000 MB - ] Warning: Found 1 unknown events! Is this an older tool processing a perf.data file generated by a more recent tool? If that is not the case, consider reporting to linux-kernel@vger.kernel.org. $ After: $ perf record -o - stress -t 2 -c 2 | perf inject -b > /dev/null stress: info: [9027] dispatching hogs: 2 cpu, 0 io, 0 vm, 0 hdd stress: info: [9027] successful run completed in 2s [ perf record: Woken up 3 times to write data ] [ perf record: Captured and wrote 0.000 MB - ] no symbols found in /usr/bin/stress, maybe install a debug package? no symbols found in /usr/bin/stress, maybe install a debug package? $ Signed-off-by: David Carrillo-Cisneros <davidcc@google.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: He Kuang <hekuang@huawei.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Paul Turner <pjt@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Simon Que <sque@chromium.org> Cc: Stephane Eranian <eranian@google.com> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/20170410201432.24807-3-davidcc@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-11 03:14:27 +07:00
event->event = NULL;
}
int ordered_events__queue(struct ordered_events *oe, union perf_event *event,
u64 timestamp, u64 file_offset)
{
struct ordered_event *oevent;
if (!timestamp || timestamp == ~0ULL)
return -ETIME;
if (timestamp < oe->last_flush) {
pr_oe_time(timestamp, "out of order event\n");
pr_oe_time(oe->last_flush, "last flush, last_flush_type %d\n",
oe->last_flush_type);
oe->nr_unordered_events++;
}
oevent = ordered_events__new_event(oe, timestamp, event);
if (!oevent) {
ordered_events__flush(oe, OE_FLUSH__HALF);
oevent = ordered_events__new_event(oe, timestamp, event);
}
if (!oevent)
return -ENOMEM;
oevent->file_offset = file_offset;
return 0;
}
static int __ordered_events__flush(struct ordered_events *oe)
{
struct list_head *head = &oe->events;
struct ordered_event *tmp, *iter;
u64 limit = oe->next_flush;
u64 last_ts = oe->last ? oe->last->timestamp : 0ULL;
bool show_progress = limit == ULLONG_MAX;
struct ui_progress prog;
int ret;
if (!limit)
return 0;
if (show_progress)
ui_progress__init(&prog, oe->nr_events, "Processing time ordered events...");
list_for_each_entry_safe(iter, tmp, head, list) {
if (session_done())
return 0;
if (iter->timestamp > limit)
break;
ret = oe->deliver(oe, iter);
if (ret)
return ret;
ordered_events__delete(oe, iter);
oe->last_flush = iter->timestamp;
if (show_progress)
ui_progress__update(&prog, 1);
}
if (list_empty(head))
oe->last = NULL;
else if (last_ts <= limit)
oe->last = list_entry(head->prev, struct ordered_event, list);
if (show_progress)
ui_progress__finish();
return 0;
}
int ordered_events__flush(struct ordered_events *oe, enum oe_flush how)
{
static const char * const str[] = {
"NONE",
"FINAL",
"ROUND",
"HALF ",
};
int err;
if (oe->nr_events == 0)
return 0;
switch (how) {
case OE_FLUSH__FINAL:
oe->next_flush = ULLONG_MAX;
break;
case OE_FLUSH__HALF:
{
struct ordered_event *first, *last;
struct list_head *head = &oe->events;
first = list_entry(head->next, struct ordered_event, list);
last = oe->last;
/* Warn if we are called before any event got allocated. */
if (WARN_ONCE(!last || list_empty(head), "empty queue"))
return 0;
oe->next_flush = first->timestamp;
oe->next_flush += (last->timestamp - first->timestamp) / 2;
break;
}
case OE_FLUSH__ROUND:
case OE_FLUSH__NONE:
default:
break;
};
pr_oe_time(oe->next_flush, "next_flush - ordered_events__flush PRE %s, nr_events %u\n",
str[how], oe->nr_events);
pr_oe_time(oe->max_timestamp, "max_timestamp\n");
err = __ordered_events__flush(oe);
if (!err) {
if (how == OE_FLUSH__ROUND)
oe->next_flush = oe->max_timestamp;
oe->last_flush_type = how;
}
pr_oe_time(oe->next_flush, "next_flush - ordered_events__flush POST %s, nr_events %u\n",
str[how], oe->nr_events);
pr_oe_time(oe->last_flush, "last_flush\n");
return err;
}
void ordered_events__init(struct ordered_events *oe, ordered_events__deliver_t deliver)
{
INIT_LIST_HEAD(&oe->events);
INIT_LIST_HEAD(&oe->cache);
INIT_LIST_HEAD(&oe->to_free);
oe->max_alloc_size = (u64) -1;
oe->cur_alloc_size = 0;
oe->deliver = deliver;
}
static void
ordered_events_buffer__free(struct ordered_events_buffer *buffer,
unsigned int max, struct ordered_events *oe)
{
if (oe->copy_on_queue) {
unsigned int i;
for (i = 0; i < max; i++)
__free_dup_event(oe, buffer->event[i].event);
}
free(buffer);
}
void ordered_events__free(struct ordered_events *oe)
{
struct ordered_events_buffer *buffer, *tmp;
if (list_empty(&oe->to_free))
return;
/*
* Current buffer might not have all the events allocated
* yet, we need to free only allocated ones ...
*/
list_del(&oe->buffer->list);
ordered_events_buffer__free(oe->buffer, oe->buffer_idx, oe);
/* ... and continue with the rest */
list_for_each_entry_safe(buffer, tmp, &oe->to_free, list) {
list_del(&buffer->list);
ordered_events_buffer__free(buffer, MAX_SAMPLE_BUFFER, oe);
}
}
void ordered_events__reinit(struct ordered_events *oe)
{
ordered_events__deliver_t old_deliver = oe->deliver;
ordered_events__free(oe);
memset(oe, '\0', sizeof(*oe));
ordered_events__init(oe, old_deliver);
}