| Age | Commit message (Collapse) | Author |
|---|
|
Oops. Part of the hugetlb private reservation code was not fully
converted to use hstates.
When a huge page must be unmapped from VMAs due to a failed COW,
HPAGE_SIZE is used in the call to unmap_hugepage_range() regardless of
the page size being used. This works if the VMA is using the default
huge page size. Otherwise we might unmap too much, too little, or
trigger a BUG_ON. Rare but serious -- fix it.
Signed-off-by: Adam Litke <agl@us.ibm.com>
Cc: Jon Tollefson <kniht@linux.vnet.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
bnx2: fix poll_controller to pass proper structures and check all rx queues
niu: Fix readq implementation when architecture does not provide one.
hostap: pad the skb->cb usage in lieu of a proper fix
rtl8187 : support for Sitecom WL-168 0001 v4
mac80211: fix notify_mac function
rtl8187: Add Abocom USB ID
net: put_cmsg_compat + SO_TIMESTAMP[NS]: use same name for value as caller
tcp_htcp: last_cong bug fix
[netdrvr] smc911x: fix for driver resume (and compilation warning)
RDMA/cxgb3: deadlock in iw_cxgb3 can cause hang when configuring interface.
cxgb3 - Limit multiqueue setting to msi-x
cxgb3 - eeprom read fixes
myri10ge: fix stop/go ordering even more
|
|
Fix bnx2 so that netpoll works properly. Specifically:
1) Fix parameters to bnx2_interrupt to be a struct bnx2_napi rather than a
struct net_device
2) Fix poll_controller method to check every queue in the rx case so frames
aren't missed
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-2.6
|
|
This fixes a TX hang reported by Jesper Dangaard Brouer.
When an architecutre cannot provide a fully functional
64-bit atomic readq/writeq, the driver must implement
it's own. This is because only the driver can say whether
doing something like using two 32-bit reads to implement
the full 64-bit read will actually work properly.
In particular one of the issues is whether the top 32-bits
or the bottom 32-bits of the 64-bit register should be read
first. There could be side effects, and in fact that is
exactly the problem here.
The TX_CS register has counters in the upper 32-bits and
state bits in the lower 32-bits. A read clears the state
bits.
We would read the counter half before the state bit half.
That first read would clear the state bits, and then the
driver thinks that no interrupts are pending because the
interrupt indication state bits are seen clear every time.
Fix this by reading the bottom half before the upper half.
Tested-by: Jesper Dangaard Brouer <jdb@comx.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
My previous patch to make CONFIG_NUMA on x86_32 depend on BROKEN
turned out to be unnecessary, after all, since the source of the
hibernation vs CONFIG_NUMA problem turned out to be the fact that
we didn't take the NUMA KVA remapping into account in the
hibernation code.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
Impact: fix crash during hibernation on 32-bit NUMA
The NUMA code on x86_32 creates special memory mapping that allows
each node's pgdat to be located in this node's memory. For this
purpose it allocates a memory area at the end of each node's memory
and maps this area so that it is accessible with virtual addresses
belonging to low memory. As a result, if there is high memory,
these NUMA-allocated areas are physically located in high memory,
although they are mapped to low memory addresses.
Our hibernation code does not take that into account and for this
reason hibernation fails on all x86_32 systems with CONFIG_NUMA=y and
with high memory present. Fix this by adding a special mapping for
the NUMA-allocated memory areas to the temporary page tables created
during the last phase of resume.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
Impact: Optimize a bit the function return tracer
This patch changes the calling convention of prepare_ftrace_return to
pass its arguments by register. This will optimize it a bit and
prepare it to support dynamic tracing.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
Impact: remove spinlocks and irq disabling in function return tracer.
I've tried to figure out all of the race condition that could happen
when the tracer pushes or pops a return address trace to/from the
current thread_info.
Theory:
_ One thread can only execute on one cpu at a time. So this code
doesn't need to be SMP-safe. Just drop the spinlock.
_ The only race could happen between the current thread and an
interrupt. If an interrupt is raised, it will increase the index of
the return stack storage and then execute until the end of the
tracing to finally free the index it used. We don't need to disable
irqs.
This is theorical. In practice, I've tested it with a two-core SMP and
had no problem at all. Perhaps -tip testing could confirm it.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
Like mac80211 did, this driver makes 'clever' use of skb->cb to pass
information along with an skb as it is requeued from the virtual device
to the physical wireless device. Unfortunately, that trick no longer
works...
Unlike mac80211, code complexity and driver apathy makes this hack
the best option we have in the short run. Hopefully someone will
eventually be motivated to code a proper fix before all the effected
hardware dies.
(Above text by me. Johannes officially disavows all knowledge of this
hack. -- JWL)
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>
|
|
the Sitecom 0001 v4 with product id 0x0df6:0028, uses Realtek's
RTL8187B and work fine with new 2.6.27 driver.
Signed-off-by: John W. Linville <linville@tuxdriver.com>
|
|
The ieee80211_notify_mac() function uses ieee80211_sta_req_auth() which
in turn calls ieee80211_set_disassoc() which calls a few functions that
need to be able to sleep, so ieee80211_notify_mac() cannot use RCU
locking for the interface list and must use rtnl locking instead.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
|
|
Signed-off-by: Ivan Kuten <ivan.kuten@promwad.com>
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
|
|
Impact: File name change of trace_unlikely.c
The "unlikely" name for the tracer is quite ugly. We renamed all the
parts of it to "branch" and now it is time to rename the file too.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
Impact: added new branch tracer
Currently the tracing of branch profiling (unlikelys and likelys hit)
is only activated by the iter_ctrl. This patch adds a tracer called
"branch" that will just trace the branch profiling. The advantage
of adding this tracer is that it can be added to the ftrace selftests
on startup.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
Impact: rename of iter_ctrl unlikely to branch
The unlikely name is ugly. This patch converts the iter_ctrl command
"unlikely" and "nounlikely" to "branch" and "nobranch" respectively.
It also renames a lot of internal functions to use "branch" instead
of "unlikely".
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
Impact: name change of unlikely tracer and profiler
Ingo Molnar suggested changing the config from UNLIKELY_PROFILE
to BRANCH_PROFILING. I never did like the "unlikely" name so I
went one step farther, and renamed all the unlikely configurations
to a "BRANCH" variant.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
hrtimer: clean up unused callback modes
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx:
dmaengine: struct device - replace bus_id with dev_name(), dev_set_name()
iop-adma: use iop_paranoia() for debug BUG_ONs
iop-adma: add a dummy read to flush next descriptor update
|
|
Maciej Rutecki reported:
> I have this bug during suspend to disk:
>
> [ 188.592151] Enabling non-boot CPUs ...
> [ 188.592151] SMP alternatives: switching to SMP code
> [ 188.666058] BUG: using smp_processor_id() in preemptible
> [00000000]
> code: suspend_to_disk/2934
> [ 188.666064] caller is native_sched_clock+0x2b/0x80
Which, as noted by Linus, was caused by me, via:
7cbaef9c "sched: optimize sched_clock() a bit"
Move the rq locking a bit earlier in the initialization sequence,
that will make the sched_clock() call in init_idle() non-preemptible.
Reported-by: Maciej Rutecki <maciej.rutecki@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
IPoIB: Fix crash in path_rec_completion()
IPoIB: Fix hang in ipoib_flush_paths()
IPoIB: Don't enable NAPI when it's already enabled
RDMA/cxgb3: Fix deadlock in iw_cxgb3 (hang when configuring interface)
IB/ehca: Remove reference to special QP in case of port activation failure
IB/mlx4: Set umem field to NULL in mlx4_ib_alloc_fast_reg_mr()
mlx4_core: Fix unused variable warning
RDMA/nes: Mitigate compatibility issue regarding PCIe write credits
RDMA/nes: Fix CQ allocation scheme for multicast receive queue apps
RDMA/nes: Correct handling of PBL resources
RDMA/nes: Reindent mis-indented spinlocks
RDMA/cxgb3: Fix too-big reserved field zeroing in iwch_post_zb_read()
IB/ipath: Fix RDMA write with immediate copy of last packet
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
ALSA: hda - Fix IDT/STAC multiple HP detection
ALSA: hda - Fix input pin initialization for STAC/IDT codecs
ALSA: hda - Add missing analog-mux mixer creation for STAC9200
|
|
Don't do misalignment handling for userspace misalignment faults: just
generate an appropriate SIGBUS instead.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Don't handle the misaligned loading and storing of the SP register as in C code
that's most certainly a compiler bug.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Support misalignment handling for instructions that have kernel SP-based
address operands, including fixing those that include IMM8 or IMM16
displacements.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Fix misalignment handling for an address calculated from the sum of two
registers.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Correctly handle misalignment in MOV instructions with postinc-with-immediate
addressing mode operands. In these, the immediate value is the increment to
be applied the address register, not the displacement to the address.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Perform misalignment fixups of the MOV_Lcc instructions (move postinc memory
to register and conditionally loop).
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Allow misalignment fixup in interrupt handling in the MN10300 arch.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Fix misalignment handling of operands with register postincrement addressing.
The flag to indicate that postincrement is required should not be interpreted
as an specification of a value to be added to the address.
Also add BUGs to catch unimplemented parameter markings in the opcodes table.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Extract the displacement from an MN10300 instruction correctly in the
misalignment fixup handler.
The code should extract the displacement in LSB order, not MSB order.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Add further misalignment fixup support to the MN10300 arch, notably for ABS32
and SP+disp addressing.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Add configurable built-in testing for the MN10300 misalignment handler.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Clean up the MN10300 misalignment handler a little by:
(1) Use ilog2() rather than doing implementing log2() locally.
(2) Make format_tbl[] const and static.
(3) Making the debugging prints more consistent.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm
* 'kvm-updates/2.6.28' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm:
KVM: Fix pit memory leak if unable to allocate irq source id
KVM: ia64: fix vmm_spin_{un}lock for !CONFIG_SMP
KVM: VMX: Set IGMT bit in EPT entry
KVM: Require the PCI subsystem
x86: KVM guest: fix section mismatch warning in kvmclock.c
KVM: ia64: Use guest signal mask when blocking
KVM: MMU: increase per-vcpu rmap cache alloc size
|
|
The STACK_GROWSUP case of stack expansion was missing a test for 'prev',
which got removed by commit cb8f488c33539f096580e202f5438a809195008f
("mmap.c: deinline a few functions") by mistake.
I found my original email in "sent" folder. The patch in that mail
does NOT remove !prev. That change had beed added by someone else.
Ok, I think we are not much interested in who did it, let's
fix it for good.
[ "It looks like this was caused by me fixing rejects. That was the
fancy include-lots-of-context-so-it-wont-apply patch." - akpm ]
Reported-and-bisected-by: Helge Deller <deller@gmx.de>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (47 commits)
ACPI: pci_link: remove acpi_irq_balance_set() interface
fujitsu-laptop: Add DMI callback for Lifebook S6420
ACPI: EC: Don't do transaction from GPE handler in poll mode.
ACPI: EC: lower interrupt storm treshold
ACPICA: Use spinlock for acpi_{en|dis}able_gpe
ACPI: EC: restart failed command
ACPI: EC: wait for last write gpe
ACPI: EC: make kernel messages more useful when GPE storm is detected
ACPI: EC: revert msleep patch
thinkpad_acpi: fingers off backlight if video.ko is serving this functionality
sony-laptop: fingers off backlight if video.ko is serving this functionality
msi-laptop: fingers off backlight if video.ko is serving this functionality
fujitsu-laptop: fingers off backlight if video.ko is serving this functionality
eeepc-laptop: fingers off backlight if video.ko is serving this functionality
compal: fingers off backlight if video.ko is serving this functionality
asus-acpi: fingers off backlight if video.ko is serving this functionality
Acer-WMI: fingers off backlight if video.ko is serving this functionality
ACPI video: if no ACPI backlight support, use vendor drivers
ACPI: video: Ignore devices that aren't present in hardware
Delete an unwanted return statement at evgpe.c
...
|
|
|
|
Fix a crash in path_rec_completion() during an SM up/down loop. If
more than one path record request is issued, the first completion
releases path->done, allowing ipoib_flush_paths() to free the path,
and thus corrupting it for the second completion.
Commit ee1e2c82 ("IPoIB: Refresh paths instead of flushing them on SM
change events") added the field path->valid and changed the test "if
(!path)" to "if (!path || !path->valid)". This change made it
possible for a path with an outstanding query to pass the test and
issue another query on the same path. Having two queries on the same
path leads to a crash.
This fixes <https://bugs.openfabrics.org/show_bug.cgi?id=1325>.
Signed-off-by: Yossi Etigin <yosefe@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
|
|
ipoib_flush_paths() can hang during an SM up/down loop: if
path_rec_start() fails (for instance, because there is no sm_ah), the
path is still added to the path list by neigh_add_path(). Then,
ipoib_flush_paths() will wait for path->done, but it will never
complete because the request was not issued at all. Fix this by
completing path->done if issuing the query fails.
This fixes <https://bugs.openfabrics.org/show_bug.cgi?id=1329>.
Signed-off-by: Yossi Etigin <yosefe@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
|
|
If a P_Key is not present when an interface is created, ipoib_open()
will return after doing napi_enable(). ipoib_open() will be called
again from ipoib_pkey_poll() when the P_Key appears, after NAPI has
already been enabled, and try to enable it again. This triggers a
BUG_ON() in napi_enable().
Fix this by moving the call to napi_enable() to after the test for
P_Key presence.
Signed-off-by: Yossi Etigin <yosefe@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
|
|
Impact: cleanup
Fix the following warning from the perl syntax checking tool perlcritic.
This tool is a lint like tool that checks for perl best practices.
Loop iterator is not lexical at line 113, column 1.
See page 108 of PBP. (Severity: 5)
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
When the iw_cxgb3 module's cxgb3_client "add" func gets called by the
cxgb3 module, the iwarp driver ends up calling the ethtool ops
get_drvinfo function in cxgb3 to get the fw version and other info.
Currently the iwarp driver grabs the rtnl lock around this down call
to serialize. As of 2.6.27 or so, things changed such that the rtnl
lock is held around the call to the netdev driver open function. Also
the cxgb3_client "add" function doesn't get called if the device is
down.
So, if you load cxgb3, then load iw_cxgb3, then ifconfig up the
device, the iw_cxgb3 add func gets called with the rtnl_lock held. If
you load cxgb3, ifconfig up the device, then load iw_cxgb3, the add
func gets called without the rtnl_lock held. The former causes the
deadlock, the latter does not.
In addition, there are iw_cxgb3 sysfs handlers that also can call down
into cxgb3 to gather the fw and hw versions. These can be called
concurrently on different processors and at any time. Thus we need to
push this serialization down in the cxgb3 driver get_drvinfo func.
The fix is to remove rtnl lock usage, and use a per-device lock in cxgb3.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Acked-by: Divy Le Ray <divy@chelsio.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
|
|
Steve suggested the to change the output from this:
> bash-3471 [003] 357.014755: [ MISS ] sched_info_dequeued:sched_stats.h:177
> bash-3471 [003] 357.014756: [ .... ] update_curr:sched_fair.c:489
> bash-3471 [003] 357.014758: [ .... ] calc_delta_fair:sched_fair.c:411
to this:
> bash-3471 [003] 357.014755: [ MISS ] sched_info_dequeued:sched_stats.h:177
> bash-3471 [003] 357.014756: [ ok ] update_curr:sched_fair.c:489
> bash-3471 [003] 357.014758: [ ok ] calc_delta_fair:sched_fair.c:411
as it makes it clearer to the user what it means exactly.
Acked-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
Impact: fix bootup crash
the branch tracer missed arch/x86/vdso/vclock_gettime.c from
disabling tracing, which caused such bootup crashes:
[ 201.840097] init[1]: segfault at 7fffed3fe7c0 ip 00007fffed3fea2e sp 000077
also clean up the ugly ifdefs in arch/x86/kernel/vsyscall_64.c by
creating DISABLE_UNLIKELY_PROFILE facility for code to turn off
instrumentation on a per file basis.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
Impact: fix load balancer load average calculation accuracy
cpu_avg_load_per_task() returns a stale value when nr_running is 0.
It returns an older stale (caculated when nr_running was non zero) value.
This patch returns and sets rq->avg_load_per_task to zero when nr_running
is 0.
Compile and boot tested on a x86_64 box.
Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
Impact: modify the tracer output, to make it a bit easier to read
Change the output from:
> bash-3471 [003] 357.014755: [INCORRECT] sched_info_dequeued:sched_stats.h:177
> bash-3471 [003] 357.014756: [correct] update_curr:sched_fair.c:489
> bash-3471 [003] 357.014758: [correct] calc_delta_fair:sched_fair.c:411
to:
> bash-3471 [003] 357.014755: [ MISS ] sched_info_dequeued:sched_stats.h:177
> bash-3471 [003] 357.014756: [ .... ] update_curr:sched_fair.c:489
> bash-3471 [003] 357.014758: [ .... ] calc_delta_fair:sched_fair.c:411
it's good to have fields aligned vertically, and the only important
information is a prediction miss, so display only that information.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
Impact: new likely/unlikely branch tracer
This patch adds a way to record the instances of the likely() and unlikely()
branch condition annotations.
When "unlikely" is set in /debugfs/tracing/iter_ctrl the unlikely conditions
will be added to any of the ftrace tracers. The change takes effect when
a new tracer is passed into the current_tracer file.
For example:
bash-3471 [003] 357.014755: [INCORRECT] sched_info_dequeued:sched_stats.h:177
bash-3471 [003] 357.014756: [correct] update_curr:sched_fair.c:489
bash-3471 [003] 357.014758: [correct] calc_delta_fair:sched_fair.c:411
bash-3471 [003] 357.014759: [correct] account_group_exec_runtime:sched_stats.h:356
bash-3471 [003] 357.014761: [correct] update_curr:sched_fair.c:489
bash-3471 [003] 357.014763: [INCORRECT] calc_delta_fair:sched_fair.c:411
bash-3471 [003] 357.014765: [correct] calc_delta_mine:sched.c:1279
Which shows the normal tracer heading, as well as whether the condition was
correct "[correct]" or was mistaken "[INCORRECT]", followed by the function,
file name and line number.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
Impact: new unlikely/likely profiler
Andrew Morton recently suggested having an in-kernel way to profile
likely and unlikely macros. This patch achieves that goal.
When configured, every(*) likely and unlikely macro gets a counter attached
to it. When the condition is hit, the hit and misses of that condition
are recorded. These numbers can later be retrieved by:
/debugfs/tracing/profile_likely - All likely markers
/debugfs/tracing/profile_unlikely - All unlikely markers.
# cat /debug/tracing/profile_unlikely | head
correct incorrect % Function File Line
------- --------- - -------- ---- ----
2167 0 0 do_arch_prctl process_64.c 832
0 0 0 do_arch_prctl process_64.c 804
2670 0 0 IS_ERR err.h 34
71230 5693 7 __switch_to process_64.c 673
76919 0 0 __switch_to process_64.c 639
43184 33743 43 __switch_to process_64.c 624
12740 64181 83 __switch_to process_64.c 594
12740 64174 83 __switch_to process_64.c 590
# cat /debug/tracing/profile_unlikely | \
awk '{ if ($3 > 25) print $0; }' |head -20
44963 35259 43 __switch_to process_64.c 624
12762 67454 84 __switch_to process_64.c 594
12762 67447 84 __switch_to process_64.c 590
1478 595 28 syscall_get_error syscall.h 51
0 2821 100 syscall_trace_leave ptrace.c 1567
0 1 100 native_smp_prepare_cpus smpboot.c 1237
86338 265881 75 calc_delta_fair sched_fair.c 408
210410 108540 34 calc_delta_mine sched.c 1267
0 54550 100 sched_info_queued sched_stats.h 222
51899 66435 56 pick_next_task_fair sched_fair.c 1422
6 10 62 yield_task_fair sched_fair.c 982
7325 2692 26 rt_policy sched.c 144
0 1270 100 pre_schedule_rt sched_rt.c 1261
1268 48073 97 pick_next_task_rt sched_rt.c 884
0 45181 100 sched_info_dequeued sched_stats.h 177
0 15 100 sched_move_task sched.c 8700
0 15 100 sched_move_task sched.c 8690
53167 33217 38 schedule sched.c 4457
0 80208 100 sched_info_switch sched_stats.h 270
30585 49631 61 context_switch sched.c 2619
# cat /debug/tracing/profile_likely | awk '{ if ($3 > 25) print $0; }'
39900 36577 47 pick_next_task sched.c 4397
20824 15233 42 switch_mm mmu_context_64.h 18
0 7 100 __cancel_work_timer workqueue.c 560
617 66484 99 clocksource_adjust timekeeping.c 456
0 346340 100 audit_syscall_exit auditsc.c 1570
38 347350 99 audit_get_context auditsc.c 732
0 345244 100 audit_syscall_entry auditsc.c 1541
38 1017 96 audit_free auditsc.c 1446
0 1090 100 audit_alloc auditsc.c 862
2618 1090 29 audit_alloc auditsc.c 858
0 6 100 move_masked_irq migration.c 9
1 198 99 probe_sched_wakeup trace_sched_switch.c 58
2 2 50 probe_wakeup trace_sched_wakeup.c 227
0 2 100 probe_wakeup_sched_switch trace_sched_wakeup.c 144
4514 2090 31 __grab_cache_page filemap.c 2149
12882 228786 94 mapping_unevictable pagemap.h 50
4 11 73 __flush_cpu_slab slub.c 1466
627757 330451 34 slab_free slub.c 1731
2959 61245 95 dentry_lru_del_init dcache.c 153
946 1217 56 load_elf_binary binfmt_elf.c 904
102 82 44 disk_put_part genhd.h 206
1 1 50 dst_gc_task dst.c 82
0 19 100 tcp_mss_split_point tcp_output.c 1126
As you can see by the above, there's a bit of work to do in rethinking
the use of some unlikelys and likelys. Note: the unlikely case had 71 hits
that were more than 25%.
Note: After submitting my first version of this patch, Andrew Morton
showed me a version written by Daniel Walker, where I picked up
the following ideas from:
1) Using __builtin_constant_p to avoid profiling fixed values.
2) Using __FILE__ instead of instruction pointers.
3) Using the preprocessor to stop all profiling of likely
annotations from vsyscall_64.c.
Thanks to Andrew Morton, Arjan van de Ven, Theodore Tso and Ingo Molnar
for their feed back on this patch.
(*) Not ever unlikely is recorded, those that are used by vsyscalls
(a few of them) had to have profiling disabled.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Theodore Tso <tytso@mit.edu>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
'tracing/ring-buffer' into tracing/core
|
