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2011-10-10x86, nmi: Track NMI usage statsDon Zickus1-2/+18
Now that the NMI handler are broken into lists, increment the appropriate stats for each list. This allows us to see what is going on when they get printed out in the next patch. Signed-off-by: Don Zickus <dzickus@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1317409584-23662-6-git-send-email-dzickus@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-10x86, nmi: Add in logic to handle multiple events and unknown NMIsDon Zickus4-9/+93
Previous patches allow the NMI subsystem to process multipe NMI events in one NMI. As previously discussed this can cause issues when an event triggered another NMI but is processed in the current NMI. This causes the next NMI to go unprocessed and become an 'unknown' NMI. To handle this, we first have to flag whether or not the NMI handler handled more than one event or not. If it did, then there exists a chance that the next NMI might be already processed. Once the NMI is flagged as a candidate to be swallowed, we next look for a back-to-back NMI condition. This is determined by looking at the %rip from pt_regs. If it is the same as the previous NMI, it is assumed the cpu did not have a chance to jump back into a non-NMI context and execute code and instead handled another NMI. If both of those conditions are true then we will swallow any unknown NMI. There still exists a chance that we accidentally swallow a real unknown NMI, but for now things seem better. An optimization has also been added to the nmi notifier rountine. Because x86 can latch up to one NMI while currently processing an NMI, we don't have to worry about executing _all_ the handlers in a standalone NMI. The idea is if multiple NMIs come in, the second NMI will represent them. For those back-to-back NMI cases, we have the potentail to drop NMIs. Therefore only execute all the handlers in the second half of a detected back-to-back NMI. Signed-off-by: Don Zickus <dzickus@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1317409584-23662-5-git-send-email-dzickus@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-10x86, nmi: Wire up NMI handlers to new routinesDon Zickus16-281/+124
Just convert all the files that have an nmi handler to the new routines. Most of it is straight forward conversion. A couple of places needed some tweaking like kgdb which separates the debug notifier from the nmi handler and mce removes a call to notify_die. [Thanks to Ying for finding out the history behind that mce call https://lkml.org/lkml/2010/5/27/114 And Boris responding that he would like to remove that call because of it https://lkml.org/lkml/2011/9/21/163] The things that get converted are the registeration/unregistration routines and the nmi handler itself has its args changed along with code removal to check which list it is on (most are on one NMI list except for kgdb which has both an NMI routine and an NMI Unknown routine). Signed-off-by: Don Zickus <dzickus@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Corey Minyard <minyard@acm.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Robert Richter <robert.richter@amd.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Corey Minyard <minyard@acm.org> Cc: Jack Steiner <steiner@sgi.com> Link: http://lkml.kernel.org/r/1317409584-23662-4-git-send-email-dzickus@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-10x86, nmi: Create new NMI handler routinesDon Zickus2-0/+171
The NMI handlers used to rely on the notifier infrastructure. This worked great until we wanted to support handling multiple events better. One of the key ideas to the nmi handling is to process _all_ the handlers for each NMI. The reason behind this switch is because NMIs are edge triggered. If enough NMIs are triggered, then they could be lost because the cpu can only latch at most one NMI (besides the one currently being processed). In order to deal with this we have decided to process all the NMI handlers for each NMI. This allows the handlers to determine if they recieved an event or not (the ones that can not determine this will be left to fend for themselves on the unknown NMI list). As a result of this change it is now possible to have an extra NMI that was destined to be received for an already processed event. Because the event was processed in the previous NMI, this NMI gets dropped and becomes an 'unknown' NMI. This of course will cause printks that scare people. However, we prefer to have extra NMIs as opposed to losing NMIs and as such are have developed a basic mechanism to catch most of them. That will be a later patch. To accomplish this idea, I unhooked the nmi handlers from the notifier routines and created a new mechanism loosely based on doIRQ. The reason for this is the notifier routines have a couple of shortcomings. One we could't guarantee all future NMI handlers used NOTIFY_OK instead of NOTIFY_STOP. Second, we couldn't keep track of the number of events being handled in each routine (most only handle one, perf can handle more than one). Third, I wanted to eventually display which nmi handlers are registered in the system in /proc/interrupts to help see who is generating NMIs. The patch below just implements the new infrastructure but doesn't wire it up yet (that is the next patch). Its design is based on doIRQ structs and the atomic notifier routines. So the rcu stuff in the patch isn't entirely untested (as the notifier routines have soaked it) but it should be double checked in case I copied the code wrong. Signed-off-by: Don Zickus <dzickus@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1317409584-23662-3-git-send-email-dzickus@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-10x86, nmi: Split out nmi from traps.cDon Zickus3-156/+179
The nmi stuff is changing a lot and adding more functionality. Split it out from the traps.c file so it doesn't continue to pollute that file. This makes it easier to find and expand all the future nmi related work. No real functional changes here. Signed-off-by: Don Zickus <dzickus@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1317409584-23662-2-git-send-email-dzickus@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-10perf, intel: Use GO/HO bits in perf-ctrGleb Natapov3-3/+112
Intel does not have guest/host-only bit in perf counters like AMD does. To support GO/HO bits KVM needs to switch EVENTSELn values (or PERF_GLOBAL_CTRL if available) at a guest entry. If a counter is configured to count only in a guest mode it stays disabled in a host, but VMX is configured to switch it to enabled value during guest entry. This patch adds GO/HO tracking to Intel perf code and provides interface for KVM to get a list of MSRs that need to be switched on a guest entry. Only cpus with architectural PMU (v1 or later) are supported with this patch. To my knowledge there is not p6 models with VMX but without architectural PMU and p4 with VMX are rare and the interface is general enough to support them if need arise. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1317816084-18026-7-git-send-email-gleb@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-06perf, amd: Use GO/HO bits in perf-ctrJoerg Roedel2-0/+16
The AMD perf-counters support counting in guest or host-mode only. Make use of that feature when user-space specified guest/host-mode only counting. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1317816084-18026-3-git-send-email-gleb@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-06perf, core: Introduce attrs to count in either host or guest modeJoerg Roedel1-1/+4
The two new attributes exclude_guest and exclude_host can bes used by user-space to tell the kernel to setup performance counter to either only count while the CPU is in guest or in host mode. An additional check is also introduced to make sure user-space does not try to exclude guest and host mode from counting. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1317816084-18026-2-git-send-email-gleb@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-05Linux 3.1-rc9v3.1-rc9Linus Torvalds1-1/+1
2011-10-04PCI: Disable MPS configuration by defaultJon Mason3-3/+20
Add the ability to disable PCI-E MPS turning and using the BIOS configured MPS defaults. Due to the number of issues recently discovered on some x86 chipsets, make this the default behavior. Also, add the option for peer to peer DMA MPS configuration. Peer to peer DMA is outside the scope of this patch, but MPS configuration could prevent it from working by having the MPS on one root port different than the MPS on another. To work around this, simply make the system wide MPS the smallest possible value (128B). Signed-off-by: Jon Mason <mason@myri.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-04drm/radeon/kms: fix channel_remap setup (v2)Alex Deucher3-127/+0
Most asics just use the hw default value which requires no explicit programming. For those that need a different value, the vbios will program it properly. As such, there's no need to program these registers explicitly in the driver. Changing MC_SHARED_CHREMAP requires a reload of all data in vram otherwise its contents will be scambled. Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=40103 v2: drop now unused channel_remap functions. Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: Michel Dänzer <michel.daenzer@amd.com> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-10-04spi-topcliff-pch: Fix overrun issueTomoya MORINAGA1-5/+23
We found that adding load, Rx data sometimes drops.(with DMA transfer mode) The cause is that before starting Rx-DMA processing, Tx-DMA processing starts. This causes FIFO overrun occurs. This patch fixes the issue by modifying FIFO tx-threshold and DMA descriptor size like below. Current this patch Rx-descriptor 4Byte+12Byte*341 --> 12Byte*340-4Byte-12Byte Rx-threshold (Not modified) Tx-descriptor 4Byte+12Byte*341 --> 16Byte-12Byte*340 Rx-threshold 12Byte --> 2Byte Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-10-04spi-topcliff-pch: Add recovery processing in case FIFO overrun error occursTomoya MORINAGA1-7/+24
Add recovery processing in case FIFO overrun error occurs with DMA transfer mode. Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-10-04spi-topcliff-pch: Fix CPU read complete condition issueTomoya MORINAGA1-8/+11
We found Rx data sometimes drops.(with non-DMA transfer mode) The cause is read complete condition is not true. This patch fixes the issue. Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-10-04spi-topcliff-pch: Fix SSN Control issueTomoya MORINAGA1-7/+3
During processing 1 command/data series, SSN should keep LOW. However, currently, SSN becomes HIGH. This patch fixes the issue. Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-10-04spi-topcliff-pch: add tx-memory clear after complete transmittingTomoya MORINAGA1-0/+5
Currently, in case of reading date from SPI flash, command is sent twice. The cause is that tx-memory clear processing is missing . This patch adds the tx-momory clear processing. Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-10-04perf: Fix counter of ftrace eventsAndrew Vagin1-0/+3
Each event adds some points to its counters. By default it adds 1, and a number of points may be transmited in event's parameters. E.g. sched:sched_stat_runtime adds how long process has been running. But this functionality was broken by v2.6.31-rc5-392-gf413cdb and now the event's parameters doesn't affect on a number of points. TP_perf_assign isn't defined, so __perf_count(c) isn't executed and __count is always equal to 1. Signed-off-by: Andrew Vagin <avagin@openvz.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1317052535-1765247-2-git-send-email-avagin@openvz.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04lis3: fix regression of HP DriveGuard with 8bit chipTakashi Iwai1-6/+8
Commit 2a7fade7e03 ("hwmon: lis3: Power on corrections") caused a regression on HP laptops with 8bit chip. Writing CTRL2_BOOT_8B bit seems clearing the BIOS setup, and no proper interrupt for DriveGuard will be triggered any more. Since the init code there is basically only for embedded devices, put a pdata check so that the problematic initialization will be skipped for hp_accel stuff. Signed-off-by: Takashi Iwai <tiwai@suse.de> Cc: Eric Piel <eric.piel@tremplin-utc.net> Cc: Samu Onkalo <samu.p.onkalo@nokia.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-03ide-disk: Fix request requeuingBorislav Petkov1-1/+6
Simon Kirby reported that on his RAID setup with idedisk underneath the box OOMs after a couple of days of runtime. Running with CONFIG_DEBUG_KMEMLEAK pointed to idedisk_prep_fn() which unconditionally allocates an ide_cmd struct. However, ide_requeue_and_plug() can be called more than once per request, either from the request issue or the IRQ handler path and do blk_peek_request() ends up in idedisk_prep_fn() repeatedly, allocating a struct ide_cmd everytime and "forgetting" the previous pointer. Make sure the code reuses the old allocated chunk. Reported-and-tested-by: Simon Kirby <sim@hostway.ca> Cc: <stable@kernel.org> [ 39.x, 3.0.x ] Link: http://marc.info/?l=linux-kernel&m=131667641517919 Link: http://lkml.kernel.org/r/20110922072643.GA27232@hostway.ca Signed-off-by: Borislav Petkov <bp@alien8.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-03pch_gbe: Fixed the issue on which a network freezesToshiharu Okada1-29/+27
The pch_gbe driver has an issue which a network stops, when receiving traffic is high. In the case, The link down and up are necessary to return a network. This patch fixed this issue. Signed-off-by: Toshiharu Okada <toshiharu-linux@dsn.okisemi.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-03pch_gbe: Fixed the issue on which PC was frozen when link was downed.Toshiharu Okada1-1/+1
When a link was downed during network use, there is an issue on which PC freezes. This patch fixed this issue. Signed-off-by: Toshiharu Okada <toshiharu-linux@dsn.okisemi.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-03make PACKET_STATISTICS getsockopt report consistently between ring and non-ringWillem de Bruijn1-1/+4
This is a minor change. Up until kernel 2.6.32, getsockopt(fd, SOL_PACKET, PACKET_STATISTICS, ...) would return total and dropped packets since its last invocation. The introduction of socket queue overflow reporting [1] changed drop rate calculation in the normal packet socket path, but not when using a packet ring. As a result, the getsockopt now returns different statistics depending on the reception method used. With a ring, it still returns the count since the last call, as counts are incremented in tpacket_rcv and reset in getsockopt. Without a ring, it returns 0 if no drops occurred since the last getsockopt and the total drops over the lifespan of the socket otherwise. The culprit is this line in packet_rcv, executed on a drop: drop_n_acct: po->stats.tp_drops = atomic_inc_return(&sk->sk_drops); As it shows, the new drop number it taken from the socket drop counter, which is not reset at getsockopt. I put together a small example that demonstrates the issue [2]. It runs for 10 seconds and overflows the queue/ring on every odd second. The reported drop rates are: ring: 16, 0, 16, 0, 16, ... non-ring: 0, 15, 0, 30, 0, 46, 0, 60, 0 , 74. Note how the even ring counts monotonically increase. Because the getsockopt adds tp_drops to tp_packets, total counts are similarly reported cumulatively. Long story short, reinstating the original code, as the below patch does, fixes the issue at the cost of additional per-packet cycles. Another solution that does not introduce per-packet overhead is be to keep the current data path, record the value of sk_drops at getsockopt() at call N in a new field in struct packetsock and subtract that when reporting at call N+1. I'll be happy to code that, instead, it's just more messy. [1] http://patchwork.ozlabs.org/patch/35665/ [2] http://kernel.googlecode.com/files/test-packetsock-getstatistics.c Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-03net: xen-netback: correctly restart Tx after a VM restore/migrateDavid Vrabel1-2/+2
If a VM is saved and restored (or migrated) the netback driver will no longer process any Tx packets from the frontend. xenvif_up() does not schedule the processing of any pending Tx requests from the front end because the carrier is off. Without this initial kick the frontend just adds Tx requests to the ring without raising an event (until the ring is full). This was caused by 47103041e91794acdbc6165da0ae288d844c820b (net: xen-netback: convert to hw_features) which reordered the calls to xenvif_up() and netif_carrier_on() in xenvif_connect(). Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-03bonding: properly stop queuing work when requestedAndy Gospodarek3-7/+12
During a test where a pair of bonding interfaces using ARP monitoring were both brought up and torn down (with an rmmod) repeatedly, a panic in the timer code was noticed. I tracked this down and determined that any of the bonding functions that ran as workqueue handlers and requeued more work might not properly exit when the module was removed. There was a flag protected by the bond lock called kill_timers that is set when the interface goes down or the module is removed, but many of the functions that monitor link status now unlock the bond lock to take rtnl first. There is a chance that another CPU running the rmmod could get the lock and set kill_timers after the first check has passed. This patch does not allow any function to queue work that will make itself run unless kill_timers is not set. I also noticed while doing this work that bond_resend_igmp_join_requests did not have a check for kill_timers, so I added the needed call there as well. Signed-off-by: Andy Gospodarek <andy@greyhouse.net> Reported-by: Liang Zheng <lzheng@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-03drm/radeon: Set cursor x/y to 0 when x/yorigin > 0.Michel Dänzer1-10/+10
Apart from the obvious cleanup, this should make the line cursor_end = x - xorigin + w; correct now. Signed-off-by: Michel Dänzer <michel.daenzer@amd.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-10-03drm/radeon: Update AVIVO cursor coordinate origin before x/yorigin calculation.Michel Dänzer1-5/+7
Fixes cursor disappearing prematurely when moving off a top/left edge which is not located at the desktop top/left edge. Signed-off-by: Michel Dänzer <michel.daenzer@amd.com> Cc: stable@kernel.org Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-10-03drm/radeon: Simplify cursor x/yorigin calculation.Michel Dänzer1-6/+2
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-10-03drm/radeon/kms: fix cursor image off-by-one errorNicholas Miell1-2/+2
The mouse cursor hotspot calculation when the cursor is partially off the top or left side of the screen was off by one. Fixes https://bugs.freedesktop.org/show_bug.cgi?id=41158 Signed-off-by: Nicholas Miell <nmiell@gmail.com> Reviewed-by: Michel Dänzer <michel@daenzer.net> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-10-03drm/radeon/kms: Fix logic error in DP HPD handlerAlex Deucher1-4/+4
Only disable the pipe if the monitor is physically disconnected. The previous logic also disabled the pipe if the link was trained. Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=41248 Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-10-03drm/radeon/kms: add retry limits for native DP aux deferAlex Deucher1-4/+8
The previous code could potentially loop forever. Limit the number of DP aux defer retries to 4 for native aux transactions, same as i2c over aux transactions. Noticed by: Brad Campbell <lists2009@fnarfbargle.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Cc: Brad Campbell <lists2009@fnarfbargle.com> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-10-03drm/radeon/kms: fix regression in DP aux defer handlingAlex Deucher1-2/+2
An incorrect ordering in the error checking code lead to DP aux defer being skipped in the aux native write path. Move the bytes transferred check (ret == 0) below the defer check. Tracked down by: Brad Campbell <brad@fnarfbargle.com> Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=41121 Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Cc: Brad Campbell <brad@fnarfbargle.com> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-10-02ASoC: omap_mcpdm_remove cannot be __devexitArnd Bergmann2-2/+2
omap_mcpdm_remove is used from asoc_mcpdm_probe, which is an initcall, and must not be discarded when HOTPLUG is disabled. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-10-02ASoC: Fix setting update bits for WM8753_LADC and WM8753_RADCAxel Lin1-2/+2
Current code set update bits for WM8753_LDAC and WM8753_RDAC twice, but missed setting update bits for WM8753_LADC and WM8753_RADC. I think it is a copy-paste bug in commit 776065 "ASoC: codecs: wm8753: Fix register cache incoherency". Signed-off-by: Axel Lin <axel.lin@gmail.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: stable@kernel.org
2011-10-02ASoC: use a valid device for dev_err() in ZyloniteArnd Bergmann1-4/+4
A recent conversion has introduced references to &pdev->dev, which does not actually exist in all the contexts it's used in. Replace this with card->dev where necessary, in order to let the driver build again. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: stable@kernel.org
2011-09-30Btrfs: force a page fault if we have a shorty copy on a page boundaryJosef Bacik1-8/+16
A user reported a problem where ceph was getting into 100% cpu usage while doing some writing. It turns out it's because we were doing a short write on a not uptodate page, which means we'd fall back at one page at a time and fault the page in. The problem is our position is on the page boundary, so our fault in logic wasn't actually reading the page, so we'd just spin forever or until the page got read in by somebody else. This will force a readpage if we end up doing a short copy. Alexandre could reproduce this easily with ceph and reports it fixes his problem. I also wrote a reproducer that no longer hangs my box with this patch. Thanks, Reported-and-tested-by: Alexandre Oliva <aoliva@redhat.com> Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-09-30posix-cpu-timers: Cure SMP wobblesPeter Zijlstra3-27/+3
David reported: Attached below is a watered-down version of rt/tst-cpuclock2.c from GLIBC. Just build it with "gcc -o test test.c -lpthread -lrt" or similar. Run it several times, and you will see cases where the main thread will measure a process clock difference before and after the nanosleep which is smaller than the cpu-burner thread's individual thread clock difference. This doesn't make any sense since the cpu-burner thread is part of the top-level process's thread group. I've reproduced this on both x86-64 and sparc64 (using both 32-bit and 64-bit binaries). For example: [davem@boricha build-x86_64-linux]$ ./test process: before(0.001221967) after(0.498624371) diff(497402404) thread: before(0.000081692) after(0.498316431) diff(498234739) self: before(0.001223521) after(0.001240219) diff(16698) [davem@boricha build-x86_64-linux]$ The diff of 'process' should always be >= the diff of 'thread'. I make sure to wrap the 'thread' clock measurements the most tightly around the nanosleep() call, and that the 'process' clock measurements are the outer-most ones. --- #include <unistd.h> #include <stdio.h> #include <stdlib.h> #include <time.h> #include <fcntl.h> #include <string.h> #include <errno.h> #include <pthread.h> static pthread_barrier_t barrier; static void *chew_cpu(void *arg) { pthread_barrier_wait(&barrier); while (1) __asm__ __volatile__("" : : : "memory"); return NULL; } int main(void) { clockid_t process_clock, my_thread_clock, th_clock; struct timespec process_before, process_after; struct timespec me_before, me_after; struct timespec th_before, th_after; struct timespec sleeptime; unsigned long diff; pthread_t th; int err; err = clock_getcpuclockid(0, &process_clock); if (err) return 1; err = pthread_getcpuclockid(pthread_self(), &my_thread_clock); if (err) return 1; pthread_barrier_init(&barrier, NULL, 2); err = pthread_create(&th, NULL, chew_cpu, NULL); if (err) return 1; err = pthread_getcpuclockid(th, &th_clock); if (err) return 1; pthread_barrier_wait(&barrier); err = clock_gettime(process_clock, &process_before); if (err) return 1; err = clock_gettime(my_thread_clock, &me_before); if (err) return 1; err = clock_gettime(th_clock, &th_before); if (err) return 1; sleeptime.tv_sec = 0; sleeptime.tv_nsec = 500000000; nanosleep(&sleeptime, NULL); err = clock_gettime(th_clock, &th_after); if (err) return 1; err = clock_gettime(my_thread_clock, &me_after); if (err) return 1; err = clock_gettime(process_clock, &process_after); if (err) return 1; diff = process_after.tv_nsec - process_before.tv_nsec; printf("process: before(%lu.%.9lu) after(%lu.%.9lu) diff(%lu)\n", process_before.tv_sec, process_before.tv_nsec, process_after.tv_sec, process_after.tv_nsec, diff); diff = th_after.tv_nsec - th_before.tv_nsec; printf("thread: before(%lu.%.9lu) after(%lu.%.9lu) diff(%lu)\n", th_before.tv_sec, th_before.tv_nsec, th_after.tv_sec, th_after.tv_nsec, diff); diff = me_after.tv_nsec - me_before.tv_nsec; printf("self: before(%lu.%.9lu) after(%lu.%.9lu) diff(%lu)\n", me_before.tv_sec, me_before.tv_nsec, me_after.tv_sec, me_after.tv_nsec, diff); return 0; } This is due to us using p->se.sum_exec_runtime in thread_group_cputime() where we iterate the thread group and sum all data. This does not take time since the last schedule operation (tick or otherwise) into account. We can cure this by using task_sched_runtime() at the cost of having to take locks. This also means we can (and must) do away with thread_group_sched_runtime() since the modified thread_group_cputime() is now more accurate and would deadlock when called from thread_group_sched_runtime(). Aside of that it makes the function safe on 32 bit systems. The old code added t->se.sum_exec_runtime unprotected. sum_exec_runtime is a 64bit value and could be changed on another cpu at the same time. Reported-by: David Miller <davem@davemloft.net> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: stable@kernel.org Link: http://lkml.kernel.org/r/1314874459.7945.22.camel@twins Tested-by: David Miller <davem@davemloft.net> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-09-30ALSA: hda - Fix a regression of the position-buffer checkTakashi Iwai1-4/+5
The commit a810364a0424c297242c6c66071a42f7675a5568 ALSA: hda - Handle -1 as invalid position, too caused a regression on some machines that require the position-buffer instead of LPIB, e.g. resulting in noises with mic recording with PulseAudio. This patch fixes the detection by delaying the test at the timing as same as 3.0, i.e. doing the position check only when requested in azx_position_ok(). Reported-and-tested-by: Rocko Requin <rockorequin@hotmail.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-09-30Resource: fix wrong resource window calculationRam Pai1-1/+6
__find_resource() incorrectly returns a resource window which overlaps an existing allocated window. This happens when the parent's resource-window spans 0x00000000 to 0xffffffff and is entirely allocated to all its children resource-windows. __find_resource() looks for gaps in resource allocation among the children resource windows. When it encounters the last child window it blindly tries the range next to one allocated to the last child. Since the last child's window ends at 0xffffffff the calculation overflows, leading the algorithm to believe that any window in the range 0x0000000 to 0xfffffff is available for allocation. This leads to a conflicting window allocation. Michal Ludvig reported this issue seen on his platform. The following patch fixes the problem and has been verified by Michal. I believe this bug has been there for ages. It got exposed by git commit 2bbc6942273b ("PCI : ability to relocate assigned pci-resources") Signed-off-by: Ram Pai <linuxram@us.ibm.com> Tested-by: Michal Ludvig <mludvig@logix.net.nz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-30powerpc: Fix device-tree matching for Apple U4 bridgeBenjamin Herrenschmidt1-0/+14
Apple Quad G5 has some oddity in it's device-tree which causes the new generic matching code to fail to relate nodes for PCI-E devices below U4 with their respective struct pci_dev. This breaks graphics on those machines among others. This fixes it using a quirk which copies the node pointer from the host bridge for the root complex, which makes the generic code work for the children afterward. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-30bootup: move 'usermodehelper_enable()' a little earlierwangyanqing1-1/+1
Commit d5767c53535a ("bootup: move 'usermodehelper_enable()' to the end of do_basic_setup()") moved 'usermodehelper_enable()' to end of do_basic_setup() to after the initcalls. But then I get failed to let uvesafb work on my computer, and lose the splash boot. So maybe we could start usermodehelper_enable a little early to make some task work that need eary init with the help of user mode. [ I would *really* prefer that initcalls not call into user space - even the real 'init' hasn't been execve'd yet, after all! But for uvesafb it really does look like we don't have much choice. I considered doing this when we mount the root filesystem, but depending on config options that is in multiple places. We could do the usermode helper enable as a rootfs_initcall().. So I'm just using wang yanqing's trivial patch. It's not wonderful, but it's simple and should work. We should revisit this some day, though. - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-29perf symbols: Treat all memory maps without dso file as loadedJiri Olsa1-6/+18
The stack/vdso/heap memory maps dont have any dso file. Setting the perf dso objects as 'loaded' for these maps, we avoid unnecessary warnings like: "Failed to open [stack], continuing without symbols" All map__find_* functions still return NULL when searching for symbols in these maps. Link: http://lkml.kernel.org/r/20110824131834.GA2007@jolsa.brq.redhat.com Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-09-29perf sched: Fix script command documentationJiri Olsa1-3/+3
Fixed leftover from trace -> script rename. Link: http://lkml.kernel.org/r/1317114995-4534-1-git-send-email-jolsa@redhat.com Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-09-29perf report: Fix stdio event name header printingArnaldo Carvalho de Melo1-4/+1
In the past we tried to avoid printing the name of the event when just one event was found in the perf.data file, after some refactorings it ended up not printing the event name if just one hist_entry was found in one of the events. Fix it by always printing the name of the event, even if just one is found. Reported-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-kikr0c7ou55bd9caok8569rf@git.kernel.org Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-09-29perf: Support setting the disassembler styleAndi Kleen6-1/+17
Add -M option to report/annotate to pass directly to objdump. This allows to use -M intel for intel style disassembler syntax, which is useful for people who are very used to the Intel syntax. Link: http://lkml.kernel.org/r/1316122302-24306-2-git-send-email-andi@firstfloor.org [committer note: Add missing Documentation bits, fixup conflicts with 3e6a2a7] Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Stephane Eranian <eranian@google.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-09-29perf tools: Make stat/record print fatal signals of the target programAndi Kleen2-2/+19
When a program crashes under perf there is no message about it, unlike when running it from bash. This can be confusing and lead to wrong actions during debugging. Print fatal signals in perf stat/record. Thanks to Furat Afram for finding the problem originally Link: http://lkml.kernel.org/r/1316122302-24306-1-git-send-email-andi@firstfloor.org Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Stephane Eranian <eranian@google.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-09-29perf stat: Fix spelling in commentJim Cromie1-1/+1
Link: http://lkml.kernel.org/r/1315437244-3788-6-git-send-email-jim.cromie@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-09-29perf stat: Allow tab as cvs delimiterJim Cromie1-2/+4
If option -x '\t' is given, convert '\t' to "\t". This makes cvs printing more flexible. Link: http://lkml.kernel.org/r/1315437244-3788-5-git-send-email-jim.cromie@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-09-29perf stat: Suppress printing std-dev when its 0Jim Cromie1-1/+1
For pretty output only (preserve column for cvs output), dont print std-deviation when its 0.00. Do this based upon value, instead of checking for --no-aggr, since the stats could conceivably be computed over the runs on each CPU, and theres no reason to preclude that. Link: http://lkml.kernel.org/r/1315437244-3788-4-git-send-email-jim.cromie@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-09-29perf stat: Fix +- nan% in --no-aggr runsJim Cromie1-2/+7
Without this patch, running: $ sudo ./perf stat -r20 --no-aggr -a perl -e '$i++ for 1..100000' I get computations like this: CPU0 12.488247 task-clock # 1.224 CPUs utilized ( +- -nan% ) CPU1 12.488909 task-clock # 1.225 CPUs utilized ( +- -nan% ) CPU2 12.500221 task-clock # 1.226 CPUs utilized ( +- -nan% ) CPU3 12.481713 task-clock # 1.224 CPUs utilized ( +- -nan% ) but with patch, I get: CPU0 8.233682 task-clock # 0.754 CPUs utilized ( +- 0.00% ) CPU1 8.226318 task-clock # 0.754 CPUs utilized ( +- 0.00% ) CPU2 8.210737 task-clock # 0.752 CPUs utilized ( +- 0.00% ) CPU3 8.201691 task-clock # 0.751 CPUs utilized ( +- 0.00% ) Note that without --no-aggr, I get non-0 statistics both before and after patch: 231.986022 task-clock # 4.030 CPUs utilized ( +- 0.97% ) 212 context-switches # 0.001 M/sec ( +- 12.07% ) 9 CPU-migrations # 0.000 M/sec ( +- 25.80% ) 466 page-faults # 0.002 M/sec ( +- 3.23% ) 174,318,593 cycles # 0.751 GHz ( +- 1.06% ) I couldnt see anything wrong in the caller, so fixed it in stddev_stats(). ISTM that 0.00 is better than nan, since perf stat was passed -A (--no-aggr) so no standard deviation should be expected, and nan is suggestive of a deeper error. When running with --no-aggr, perhaps we should suppress the statistics printing entirely, or do so when they are 0.00. Link: http://lkml.kernel.org/r/1315437244-3788-3-git-send-email-jim.cromie@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-09-29perf stat: Add --log-fd <N> option to redirect stderr elsewhereJim Cromie2-1/+24
This perf stat option emulates valgrind's --log-fd option, allowing the user to send perf results elsewhere, and leaving stderr for use by the program under test. This complements --output file option, and is mutually exclusive with it. 3>results perf stat --log-fd 3 -- $cmd 3>>results perf stat --log-fd 3 --append -- $cmd The perl distro's make test.valgrind target uses valgrind's --log-fd option, I've adapted it to invoke perf also, and tested this patch there. Link: http://lkml.kernel.org/r/1315437244-3788-2-git-send-email-jim.cromie@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>