Steven Rostedt
a63ce5b306
tracing: Buffer the output of seq_file in case of filled buffer ...
If the seq_read fills the buffer it will call s_start again on the next
itertation with the same position. This causes a problem with the
function_graph tracer because it consumes the iteration in order to
determine leaf functions.
What happens is that the iterator stores the entry, and the function
graph plugin will look at the next entry. If that next entry is a return
of the same function and task, then the function is a leaf and the
function_graph plugin calls ring_buffer_read which moves the ring buffer
iterator forward (the trace iterator still points to the function start
entry).
The copying of the trace_seq to the seq_file buffer will fail if the
seq_file buffer is full. The seq_read will not show this entry.
The next read by userspace will cause seq_read to again call s_start
which will reuse the trace iterator entry (the function start entry).
But the function return entry was already consumed. The function graph
plugin will think that this entry is a nested function and not a leaf.
To solve this, the trace code now checks the return status of the
seq_printf (trace_print_seq). If the writing to the seq_file buffer
fails, we set a flag in the iterator (leftover) and we do not reset
the trace_seq buffer. On the next call to s_start, we check the leftover
flag, and if it is set, we just reuse the trace_seq buffer and do not
call into the plugin print functions.
Before this patch:
2) | fput() {
2) | __fput() {
2) 0.550 us | inotify_inode_queue_event();
2) | __fsnotify_parent() {
2) 0.540 us | inotify_dentry_parent_queue_event();
After the patch:
2) | fput() {
2) | __fput() {
2) 0.550 us | inotify_inode_queue_event();
2) 0.548 us | __fsnotify_parent();
2) 0.540 us | inotify_dentry_parent_queue_event();
[
Updated the patch to fix a missing return 0 from the trace_print_seq()
stub when CONFIG_TRACING is disabled.
Reported-by: Ingo Molnar <mingo@elte.hu>
]
Reported-by: Jiri Olsa <jolsa@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-12-09 13:55:26 -05:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
2009-10-09 13:32:24 -07:00
mfd: Correct WM831X_MAX_ISEL_VALUE
2009-12-01 11:24:19 +01:00
headers: remove sched.h from interrupt.h
2009-10-11 11:20:58 -07:00
Merge branch 'for-linus' of git://git.o-hand.com/linux-rpurdie-backlight
2009-09-26 10:49:42 -07:00
sunrpc: xdr_xcode_hyper helpers cannot presume 64-bit alignment
2009-09-23 14:36:38 -04:00
include/linux/unaligned/{l,b}e_byteshift.h: fix usage for compressed kernels
2009-09-24 07:21:05 -07:00
USB: serial: don't call release without attach
2009-10-09 13:52:05 -07:00
const: mark struct vm_struct_operations
2009-09-27 11:39:25 -07:00
libata: implement more acpi filtering options
2009-10-06 00:26:26 -04:00
net: Make setsockopt() optlen be unsigned.
2009-09-30 16:12:20 -07:00
writeback: pass in super_block to bdi_start_writeback()
2009-09-26 00:10:40 +02:00
exec: fix set_binfmt() vs sys_delete_module() race
2009-09-24 07:21:01 -07:00
block: get rid of kblock_schedule_delayed_work()
2009-10-05 11:03:58 +02:00
Add a tracepoint for block request remapping
2009-10-01 21:19:34 +02:00
bootmem: Add free_bootmem_late()
2009-11-10 12:31:43 +01:00
remove CONFIG_SECURITY_FILE_CAPABILITIES compile option
2009-11-24 15:06:47 +11:00
const: constify remaining file_operations
2009-10-01 16:11:11 -07:00
compiler: Introduce __always_unused
2009-11-02 15:47:54 +01:00
Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-12-05 15:32:03 -08:00
Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-12-05 15:32:03 -08:00
docs: fix various Documentation/ paths in header files
2009-09-24 07:20:57 -07:00
connector: Removed the destruct_data callback since it is always kfree_skb()
2009-10-02 10:54:05 -07:00
cpufreq: add cpufreq_get() stub for CONFIG_CPU_FREQ=n
2009-10-29 07:39:24 -07:00
cpumask: Move deprecated functions to end of header.
2009-09-24 09:34:53 +09:30
include/linux/cred.h: fix build
2009-09-23 11:01:25 -07:00
docs: fix various Documentation/ paths in header files
2009-09-24 07:20:57 -07:00
Driver core: allow certain drivers prohibit bind/unbind via sysfs
2009-10-30 14:59:51 -07:00
x86: intel-iommu: Convert detect_intel_iommu to use iommu_init hook
2009-11-10 12:31:36 +01:00
[S390] 64-bit register support for 31-bit processes
2009-10-06 10:35:10 +02:00
ext3: Wait for proper transaction commit on fsync
2009-11-11 15:22:49 +01:00
fb: remove fb_save_state() and fb_restore_state operations
2009-11-12 07:25:56 -08:00
Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
2009-10-04 12:39:14 -07:00
CacheFiles: Catch an overly long wait for an old active object
2009-11-19 18:12:05 +00:00
FS-Cache: Handle pages pending storage that get evicted under OOM conditions
2009-11-19 18:11:35 +00:00
tracing: correct module boundaries for ftrace_release
2009-10-07 15:52:09 -04:00
tracing: Buffer the output of seq_file in case of filled buffer
2009-12-09 13:55:26 -05:00
Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-10-08 12:16:35 -07:00
block: Seperate read and write statistics of in_flight requests v2
2009-10-06 20:16:55 +02:00
GFS2: Tag all metadata with jid
2009-12-03 11:58:47 +00:00
rcu: "Tiny RCU", The Bloatwatch Edition
2009-10-26 09:40:29 +01:00
const: mark struct vm_struct_operations
2009-09-27 11:39:25 -07:00
hw-breakpoints: Use struct perf_event_attr to define kernel breakpoints
2009-11-27 06:22:59 +01:00
i2c: i2c-pnx: Made buf type unsigned to prevent sign extension
2009-11-20 00:25:42 +00:00
i2c: Add an interface to lock/unlock an I2C bus segment
2009-11-07 13:10:46 +01:00
Revert "sit: stateless autoconf for isatap"
2009-09-26 20:28:07 -07:00
initcalls: Add early_initcall() for modules
2009-10-02 15:42:19 +02:00
remove CONFIG_SECURITY_FILE_CAPABILITIES compile option
2009-11-24 15:06:47 +11:00
Input: fix locking in memoryless force-feedback devices
2009-11-10 21:13:32 -08:00
irq: Remove unused debug_poll_all_shared_irqs()
2009-11-04 14:22:21 +01:00
headers: kref.h redux
2009-09-26 10:17:19 -07:00
irq: trivial: Fix typo in comment for #endif
2009-10-23 08:28:10 +02:00
Revert "isdn: isdn_ppp: Use SKB list facilities instead of home-grown implementation."
2009-11-15 22:23:47 -08:00
jbd2: Use tracepoints for history file
2009-09-30 00:32:06 -04:00
sched, time: Define nsecs_to_jiffies()
2009-11-26 12:59:20 +01:00
Merge branch 'master' into next
2009-12-03 12:03:40 +05:30
Merge branch 'core-printk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-12-05 09:50:22 -08:00
sched, cpuacct: Fix niced guest time accounting
2009-10-25 17:31:30 +01:00
Merge commit 'linus/master' into tracing/kprobes
2009-09-23 23:08:43 +02:00
headers: kref.h redux
2009-09-26 10:17:19 -07:00
libata: make gtf_filter per-dev
2009-10-06 00:26:27 -04:00
security: report the module name to security_module_request
2009-11-10 09:33:46 +11:00
memory controller: soft limit reclaim on contention
2009-09-24 07:20:59 -07:00
NOMMU: Fallback for is_vmalloc_or_module_addr() should be inline
2009-09-24 17:20:20 -07:00
const: mark struct vm_struct_operations
2009-09-27 11:39:25 -07:00
sysctl: remove "struct file *" argument of ->proc_handler
2009-09-24 07:21:04 -07:00
module: preferred way to use MODULE_AUTHOR
2009-09-25 00:32:58 +09:30
param: fix lots of bugs with writing charp params from sysfs, by leaking mem.
2009-10-29 08:56:17 +10:30
net: Make setsockopt() optlen be unsigned.
2009-09-30 16:12:20 -07:00
net: Make setsockopt() optlen be unsigned.
2009-09-30 16:12:20 -07:00
Merge branch 'core-printk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-12-05 09:50:22 -08:00
include/linux/netdevice.h: fix nanodoc mismatch
2009-10-07 13:53:11 -07:00
net: Make setsockopt() optlen be unsigned.
2009-09-30 16:12:20 -07:00
genetlink: fix netns vs. netlink table locking (2)
2009-09-24 15:44:05 -07:00
headers: kref.h redux
2009-09-26 10:17:19 -07:00
nilfs2: deleted struct nilfs_dat_group_desc
2009-11-15 17:17:38 +09:00
Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6
2009-09-24 07:53:22 -07:00
memcg: remove the overhead associated with the root cgroup
2009-09-24 07:20:58 -07:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6
2009-12-05 09:42:59 -08:00
Merge branches 'perf/powerpc' and 'perf/bench' into perf/core
2009-11-15 09:51:24 +01:00
perf_events: Undo some recursion damage
2009-11-23 11:49:57 +01:00
Phonet: error on broadcast sending (unimplemented)
2009-09-24 15:38:57 -07:00
headers: remove sched.h from poll.h
2009-10-04 15:05:10 -07:00
VFS: Add forget_all_cached_acls()
2009-12-03 11:43:23 +00:00
HWPOISON: Clean up PR_MCE_KILL interface
2009-10-04 03:23:17 +02:00
sched: Revert 498657a478
2009-12-02 09:55:33 +01:00
VFS: Export dquot_send_warning
2009-12-03 11:53:02 +00:00
const: mark struct vm_struct_operations
2009-09-27 11:39:25 -07:00
ratelimit: Make suppressed output messages more useful
2009-10-23 17:26:37 +02:00
rcu: Re-arrange code to reduce #ifdef pain
2009-11-22 18:58:16 +01:00
rcu: Re-arrange code to reduce #ifdef pain
2009-11-22 18:58:16 +01:00
rcu: Re-arrange code to reduce #ifdef pain
2009-11-22 18:58:16 +01:00
docs: fix various Documentation/ paths in header files
2009-09-24 07:20:57 -07:00
memcg: some modification to softlimit under hierarchical memory reclaim.
2009-10-01 16:11:13 -07:00
Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6
2009-09-24 07:53:22 -07:00
Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
2009-12-05 15:30:49 -08:00
define convenient securebits masks for prctl users (v2)
2009-10-30 08:27:25 +11:00
security: report the module name to security_module_request
2009-11-10 09:33:46 +11:00
vfs: seq_file: add helpers for data filling
2009-09-24 07:47:35 -04:00
MIPS: BCM63xx: Add serial driver for bcm63xx integrated UART.
2009-09-30 21:46:59 +02:00
signals: introduce do_send_sig_info() helper
2009-09-24 07:21:01 -07:00
net: fix sk_forward_alloc corruption
2009-10-30 12:25:12 -07:00
SLOW_WORK: Move slow_work's proc file to debugfs
2009-12-01 08:20:31 -08:00
generic-ipi: Add smp_call_function_any()
2009-11-18 14:52:25 +01:00
tracing: Pushdown the bkl tracepoints calls
2009-09-28 18:00:48 +02:00
net: Support inclusion of <linux/socket.h> before <sys/socket.h>
2009-10-05 00:24:36 -07:00
locking: Use __[SPIN|RW]_LOCK_UNLOCKED in [spin|rw]_lock_init()
2009-11-24 14:41:13 +01:00
locking: Make inlining decision Kconfig based
2009-11-13 20:53:28 +01:00
rcu: Add synchronize_srcu_expedited()
2009-10-26 09:40:30 +01:00
strstrip(): mark as as must_check
2009-10-29 07:39:25 -07:00
mm: allow memory hotplug and hibernation in the same kernel
2009-11-17 17:40:33 -08:00
Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6
2009-09-24 07:53:22 -07:00
swiotlb: Remove duplicate swiotlb_force extern declarations
2009-11-15 09:03:10 +01:00
tracing/syscalls: Make syscall events print callbacks static
2009-12-02 09:59:02 +01:00
sysctl: remove "struct file *" argument of ->proc_handler
2009-09-24 07:21:04 -07:00
time: add function to convert between calendar time and broken-down time for universal use
2009-09-24 07:20:56 -07:00
sched: Disable SD_PREFER_LOCAL for MC/CPU domains
2009-10-14 15:02:34 +02:00
tpm: fix header for modular build
2009-10-29 11:17:40 +11:00
tracing: Buffer the output of seq_file in case of filled buffer
2009-12-09 13:55:26 -05:00
signals: tracehook_notify_jctl change
2009-09-24 07:21:00 -07:00
events: Rename TRACE_EVENT_TEMPLATE() to DECLARE_EVENT_CLASS()
2009-11-26 09:04:55 +01:00
tty: Fix regressions caused by commit b50989dc
2009-09-27 13:35:16 -07:00
headers: utsname.h redux
2009-09-23 18:13:10 -07:00
Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
2009-09-24 09:57:08 -07:00
virtio: let header files include virtio_ids.h
2009-10-22 16:39:28 +10:30
virtio: let header files include virtio_ids.h
2009-10-22 16:39:28 +10:30
virtio_blk: Revert serial number support
2009-10-22 16:39:30 +10:30
virtio: let header files include virtio_ids.h
2009-10-22 16:39:28 +10:30
virtio: let header files include virtio_ids.h
2009-10-22 16:39:28 +10:30
virtio: let header files include virtio_ids.h
2009-10-22 16:39:28 +10:30
vt: Fix use of "new" in a struct field
2009-11-19 13:43:06 -08:00
workqueue: add 'flush_delayed_work()' to run and wait for delayed work
2009-10-14 09:16:42 -07:00
sysctl: remove "struct file *" argument of ->proc_handler
2009-09-24 07:21:04 -07:00
