summaryrefslogtreecommitdiff
AgeCommit message (Collapse)Author
2012-01-13module_param: make bool parameters really bool (arch)Rusty Russell
module_param(bool) used to counter-intuitively take an int. In fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy trick. It's time to remove the int/unsigned int option. For this version it'll simply give a warning, but it'll break next kernel version. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13module_param: make bool parameters really bool (core code)Rusty Russell
module_param(bool) used to counter-intuitively take an int. In fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy trick. It's time to remove the int/unsigned int option. For this version it'll simply give a warning, but it'll break next kernel version. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13kernel/async: remove redundant declaration.Rusty Russell
It's in linux/init.h, and I'm about to change it to a bool. Cc: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13printk: fix unnecessary module_param_name.Rusty Russell
You don't need module_param_name if the name is the same! Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13lirc_parallel: fix module parameter description.Rusty Russell
Cut and paste bug. Cc: Mauro Carvalho Chehab <mchehab@redhat.com> Cc: devel@driverdev.osuosl.org Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13module_param: avoid bool abuse, add bint for special cases.Rusty Russell
For historical reasons, we allow module_param(bool) to take an int (or an unsigned int). That's going away. A few drivers really want an int: they set it to -1 and a parameter will set it to 0 or 1. This sucks: reading them from sysfs will give 'Y' for both -1 and 1, but if we change it to an int, then the users might be broken (if they did "param" instead of "param=1"). Use a new 'bint' parser for them. (ntfs has a different problem: it needs an int for debug_msgs because it's also exposed via sysctl.) Cc: Steve Glendinning <steve.glendinning@smsc.com> Cc: Jean Delvare <khali@linux-fr.org> Cc: Guenter Roeck <guenter.roeck@ericsson.com> Cc: Hoang-Nam Nguyen <hnguyen@de.ibm.com> Cc: Christoph Raisch <raisch@de.ibm.com> Cc: Roland Dreier <roland@kernel.org> Cc: Sean Hefty <sean.hefty@intel.com> Cc: Hal Rosenstock <hal.rosenstock@gmail.com> Cc: linux390@de.ibm.com Cc: Anton Altaparmakov <anton@tuxera.com> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Takashi Iwai <tiwai@suse.de> Cc: lm-sensors@lm-sensors.org Cc: linux-rdma@vger.kernel.org Cc: linux-s390@vger.kernel.org Cc: linux-ntfs-dev@lists.sourceforge.net Cc: alsa-devel@alsa-project.org Acked-by: Takashi Iwai <tiwai@suse.de> (For the sound part) Acked-by: Guenter Roeck <guenter.roeck@ericsson.com> (For the hwmon driver) Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13module_param: check type correctness for module_param_arrayRusty Russell
module_param_array(), unlike its non-array cousins, didn't check the type of the variable. Fixing this found two bugs. Cc: Luca Risolia <luca.risolia@studio.unibo.it> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Eric Piel <eric.piel@tremplin-utc.net> Cc: linux-media@vger.kernel.org Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13modpost: use linker section to generate table.Rusty Russell
This means (most) future busses need only have one hunk in their patch. Also took the opportunity to check that function matches the type. Again, inspired by Alessandro's patch series. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Alessandro Rubini <rubini@gnudd.com>
2012-01-13modpost: use a table rather than a giant if/else statement.Rusty Russell
We look for symbols of form __mod_<busname>_device_table, and for all but three cases we use a standard interation function (do_table) to walk over the contents and dump out the aliases. Alessandro Rubini did this first, I just repainted the bikeshed a bit. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Alessandro Rubini <rubini@gnudd.com>
2012-01-13modules: sysfs - export: taint, coresize, initsizeKay Sievers
Recent tools do not want to use /proc to retrieve module information. A few values are currently missing from sysfs to replace the information available in /proc/modules. This adds /sys/module/*/{coresize,initsize,taint} attributes. TAINT_PROPRIETARY_MODULE (P) and TAINT_OOT_MODULE (O) flags are both always shown now, and do no longer exclude each other, also in /proc/modules. Replace the open-coded sysfs attribute initializers with the __ATTR() macro. Add the new attributes to Documentation/ABI. Cc: Lucas De Marchi <lucas.demarchi@profusion.mobi> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13kernel/params: replace DEBUGP with pr_debugJim Cromie
Use more flexible pr_debug. This allows: echo "module params +p" > /dbg/dynamic_debug/control to turn on debug messages when needed. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13module: replace DEBUGP with pr_debugJim Cromie
Use more flexible pr_debug. This allows: echo "module module +p" > /dbg/dynamic_debug/control to turn on debug messages when needed. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13module: struct module_ref should contains long fieldsEric Dumazet
module_ref contains two "unsigned int" fields. Thats now too small, since some machines can open more than 2^32 files. Check commit 518de9b39e8 (fs: allow for more than 2^31 files) for reference. We can add an aligned(2 * sizeof(unsigned long)) attribute to force alloc_percpu() allocating module_ref areas in single cache lines. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Rusty Russell <rusty@rustcorp.com.au> CC: Tejun Heo <tj@kernel.org> CC: Robin Holt <holt@sgi.com> CC: David Miller <davem@davemloft.net> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13module: Fix performance regression on modules with large symbol tablesKevin Cernekee
Looking at /proc/kallsyms, one starts to ponder whether all of the extra strtab-related complexity in module.c is worth the memory savings. Instead of making the add_kallsyms() loop even more complex, I tried the other route of deleting the strmap logic and naively copying each string into core_strtab with no consideration for consolidating duplicates. Performance on an "already exists" insmod of nvidia.ko (runs add_kallsyms() but does not actually initialize the module): Original scheme: 1.230s With naive copying: 0.058s Extra space used: 35k (of a 408k module). Signed-off-by: Kevin Cernekee <cernekee@gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> LKML-Reference: <73defb5e4bca04a6431392cc341112b1@localhost>
2012-01-13module: Add comments describing how the "strmap" logic worksKevin Cernekee
Signed-off-by: Kevin Cernekee <cernekee@gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: bcm5974 - set BUTTONPAD property Input: serio_raw - return proper result when serio_raw_write fails Input: serio_raw - really signal HUP upon disconnect Input: serio_raw - remove stray semicolon Input: revert some over-zealous conversions to module_platform_driver()
2012-01-12Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: FUSE: Notifying the kernel of deletion. fuse: support ioctl on directories fuse: Use kcalloc instead of kzalloc to allocate array fuse: llseek optimize SEEK_CUR and SEEK_SET
2012-01-12Merge tag 'to-linus' of git://github.com/rustyrussell/linuxLinus Torvalds
* tag 'to-linus' of git://github.com/rustyrussell/linux: (24 commits) lguest: Make sure interrupt is allocated ok by lguest_setup_irq lguest: move the lguest tool to the tools directory lguest: switch segment-voodoo-numbers to readable symbols virtio: balloon: Add freeze, restore handlers to support S4 virtio: balloon: Move vq initialization into separate function virtio: net: Add freeze, restore handlers to support S4 virtio: net: Move vq and vq buf removal into separate function virtio: net: Move vq initialization into separate function virtio: blk: Add freeze, restore handlers to support S4 virtio: blk: Move vq initialization to separate function virtio: console: Disable callbacks for virtqueues at start of S4 freeze virtio: console: Add freeze and restore handlers to support S4 virtio: console: Move vq and vq buf removal into separate functions virtio: pci: add PM notification handlers for restore, freeze, thaw, poweroff virtio: pci: switch to new PM API virtio_blk: fix config handler race virtio: add debugging if driver doesn't kick. virtio: expose added descriptors immediately. virtio: avoid modulus operation. virtio: support unlocked queue kick ...
2012-01-12brcmsmac: fix reading of PCI sprom contentsLinus Torvalds
It appears that you can only read the sprom contents with aligned 16-bit reads: anything else causes at least some versions of the broadcom chipset to abort the PCI transaction, returning 0xff. This apparently doesn't trigger very often, because most setups don't use an external srom chip, and the OTP sprom loading doesn't have this issue. But at least the current 11" Macbook Air does trigger it, and wireless communications were broken as a result. Acked-by: Arend van Spriel <arend@broadcom.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-12x86: Get rid of 'dubious one-bit signed bitfield' sprase warningAnton Vorontsov
This very noisy sparse warning appears on almost every file in the kernel: CHECK init/main.c arch/x86/include/asm/thread_info.h:43:55: error: dubious one-bit signed bitfield arch/x86/include/asm/thread_info.h:44:46: error: dubious one-bit signed bitfield This patch changes sig_on_uaccess_error and uaccess_err flags to unsigned type and thus fixes the warning. Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com> Acked-by: Andy Lutomirski <luto@mit.edu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-12Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (526 commits) ASoC: twl6040 - Add method to query optimum PDM_DL1 gain ALSA: hda - Fix the lost power-setup of seconary pins after PM resume ALSA: usb-audio: add Yamaha MOX6/MOX8 support ALSA: virtuoso: add S/PDIF input support for all Xonars ALSA: ice1724 - Support for ooAoo SQ210a ALSA: ice1724 - Allow card info based on model only ALSA: ice1724 - Create capture pcm only for ADC-enabled configurations ALSA: hdspm - Provide unique driver id based on card serial ASoC: Dynamically allocate the rtd device for a non-empty release() ASoC: Fix recursive dependency due to select ATMEL_SSC in SND_ATMEL_SOC_SSC ALSA: hda - Fix the detection of "Loopback Mixing" control for VIA codecs ALSA: hda - Return the error from get_wcaps_type() for invalid NIDs ALSA: hda - Use auto-parser for HP laptops with cx20459 codec ALSA: asihpi - Fix potential Oops in snd_asihpi_cmode_info() ALSA: hdsp - Fix potential Oops in snd_hdsp_info_pref_sync_ref() ALSA: hda/cirrus - support for iMac12,2 model ASoC: cx20442: add bias control over a platform provided regulator ALSA: usb-audio - Avoid flood of frame-active debug messages ALSA: snd-usb-us122l: Delete calls to preempt_disable mfd: Put WM8994 into cache only mode when suspending ... Fix up trivial conflicts in: - arch/arm/mach-s3c64xx/mach-crag6410.c: renamed speyside_wm8962 to tobermory, added littlemill right next to it - drivers/base/regmap/{regcache.c,regmap.c}: duplicate diff that had already come in with other changes in the regmap tree
2012-01-12x86/PCI: build amd_bus.o only when CONFIG_AMD_NB=yBjorn Helgaas
We only need amd_bus.o for AMD systems with PCI. arch/x86/pci/Makefile already depends on CONFIG_PCI=y, so this patch just adds the dependency on CONFIG_AMD_NB. Cc: Yinghai Lu <yinghai@kernel.org> Cc: stable@kernel.org # 2.6.34+ (needs adjustment for k8 -> amd rename) Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-12Merge branch 'topic/hda' into for-linusTakashi Iwai
2012-01-12Merge branch 'topic/misc' into for-linusTakashi Iwai
2012-01-12Merge branch 'for-3.3' of ↵Takashi Iwai
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into topic/asoc
2012-01-11Merge tag 'rmobile-for-linus' of git://github.com/pmundt/linux-shLinus Torvalds
SH/R-Mobile updates for 3.3 merge window. * tag 'rmobile-for-linus' of git://github.com/pmundt/linux-sh: (32 commits) arm: mach-shmobile: add a resource name for shdma ARM: mach-shmobile: r8a7779 SMP support V3 ARM: mach-shmobile: Add kota2 defconfig. ARM: mach-shmobile: Add marzen defconfig. ARM: mach-shmobile: r8a7779 power domain support V2 ARM: mach-shmobile: Fix up marzen build for recent GIC changes. ARM: mach-shmobile: r8a7779 PFC function support ARM: mach-shmobile: Flush caches in platform_cpu_die() ARM: mach-shmobile: Allow SoC specific CPU kill code ARM: mach-shmobile: Fix headsmp.S code to use CPUINIT ARM: mach-shmobile: clock-r8a7779: clkz/clkzs support ARM: mach-shmobile: clock-r8a7779: add DIV4 clock support ARM: mach-shmobile: Marzen LAN89218 support ARM: mach-shmobile: Marzen SCIF2/SCIF4 support ARM: mach-shmobile: r8a7779 PFC GPIO-only support V2 ARM: mach-shmobile: r8a7779 and Marzen base support V2 sh: pfc: Unlock register support sh: pfc: Variable bitfield width config register support sh: pfc: Add config_reg_helper() function sh: pfc: Convert index to field and value pair ...
2012-01-11Merge tag 'sh-for-linus' of git://github.com/pmundt/linux-shLinus Torvalds
SuperH updates for 3.3 merge window. * tag 'sh-for-linus' of git://github.com/pmundt/linux-sh: (38 commits) sh: magicpanelr2: Update for parse_mtd_partitions() fallout. sh: mach-rsk: Update for parse_mtd_partitions() fallout. sh: sh2a: Improve cache flush/invalidate functions sh: also without PM_RUNTIME pm_runtime.o must be built sh: add a resource name for shdma sh: Remove redundant try_to_freeze() invocations. sh: Ensure IRQs are enabled across do_notify_resume(). sh: Fix up store queue code for subsys_interface changes. sh: clkfwk: sh_clk_init_parent() should be called after clk_register() sh: add platform_device for renesas_usbhs in board-sh7757lcr sh: modify clock-sh7757 for renesas_usbhs sh: pfc: ioremap() support sh: use ioread32/iowrite32 and mapped_reg for div6 sh: use ioread32/iowrite32 and mapped_reg for div4 sh: use ioread32/iowrite32 and mapped_reg for mstp32 sh: extend clock struct with mapped_reg member sh: clkfwk: clock-sh73a0: all div6_clks use SH_CLK_DIV6_EXT() sh: clkfwk: clock-sh7724: all div6_clks use SH_CLK_DIV6_EXT() sh: clock-sh7723: add CLKDEV_ICK_ID for cleanup serial: sh-sci: Handle GPIO function requests. ...
2012-01-11Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Fix lockup by limiting load-balance retries on lock-break sched: Fix CONFIG_CGROUP_SCHED dependency sched: Remove empty #ifdefs
2012-01-12lguest: Make sure interrupt is allocated ok by lguest_setup_irqStratos Psomadakis
Make sure the interrupt is allocated correctly by lguest_setup_irq (check the return value of irq_alloc_desc_at for -ENOMEM) Signed-off-by: Stratos Psomadakis <psomas@cslab.ece.ntua.gr> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (cleanups and commentry)
2012-01-12lguest: move the lguest tool to the tools directoryDavidlohr Bueso
This is a better location instead of having it in Documentation. Signed-off-by: Davidlohr Bueso <dave@gnu.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (fixed compile)
2012-01-12lguest: switch segment-voodoo-numbers to readable symbolsJacek Galowicz
When studying lguest's x86 segment descriptor code, it is not longer necessary to have the Intel x86 architecture manual open on the page with the segment descriptor illustration to understand the crazy numbers assigned to both descriptor structure halves a/b. Now the struct desc_struct's fields, like suggested by Glauber de Oliveira Costa in 2008, are used. Signed-off-by: Jacek Galowicz <jacek@galowicz.de> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio: balloon: Add freeze, restore handlers to support S4Amit Shah
Handling balloon hibernate / restore is tricky. If the balloon was inflated before going into the hibernation state, upon resume, the host will not have any memory of that. Any pages that were passed on to the host earlier would most likely be invalid, and the host will have to re-balloon to the previous value to get in the pre-hibernate state. So the only sane thing for the guest to do here is to discard all the pages that were put in the balloon. When to discard the pages is the next question. One solution is to deflate the balloon just before writing the image to the disk (in the freeze() PM callback). However, asking for pages from the host just to discard them immediately after seems wasteful of resources. Hence, it makes sense to do this by just fudging our counters soon after wakeup. This means we don't deflate the balloon before sleep, and also don't put unnecessary pressure on the host. This also helps in the thaw case: if the freeze fails for whatever reason, the balloon should continue to remain in the inflated state. This was tested by issuing 'swapoff -a' and trying to go into the S4 state. That fails, and the balloon stays inflated, as expected. Both the host and the guest are happy. Finally, in the restore() callback, we empty the list of pages that were previously given off to the host, add the appropriate number of pages to the totalram_pages counter, reset the num_pages counter to 0, and all is fine. As a last step, delete the vqs on the freeze callback to prepare for hibernation, and re-create them in the restore and thaw callbacks to resume normal operation. The kthread doesn't race with any operations here, since it's frozen before the freeze() call and is thawed after the thaw() and restore() callbacks, so we're safe with that. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio: balloon: Move vq initialization into separate functionAmit Shah
The probe and PM restore functions will share this code. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio: net: Add freeze, restore handlers to support S4Amit Shah
Remove all the vqs, disable napi and detach from the netdev on hibernation. Re-create vqs after restoring from a hibernated image, re-enable napi and re-attach the netdev. This keeps networking working across hibernation. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio: net: Move vq and vq buf removal into separate functionAmit Shah
The remove and PM freeze functions will share this code. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio: net: Move vq initialization into separate functionAmit Shah
The probe and PM restore functions will share this code. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio: blk: Add freeze, restore handlers to support S4Amit Shah
Delete the vq and flush any pending requests from the block queue on the freeze callback to prepare for hibernation. Re-create the vq in the restore callback to resume normal function. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio: blk: Move vq initialization to separate functionAmit Shah
The probe and PM restore functions will share this code. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio: console: Disable callbacks for virtqueues at start of S4 freezeAmit Shah
To ensure we don't receive any more interrupts from the host after we enter the freeze function, disable all vq interrupts. There wasn't any problem seen due to this in tests, but applying this patch makes the freeze case more robust. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio: console: Add freeze and restore handlers to support S4Amit Shah
Remove all vqs and associated buffers in the freeze callback which prepares us to go into hibernation state. On restore, re-create all the vqs and populate the input vqs with buffers to get to the pre-hibernate state. Note: Any outstanding unconsumed buffers are discarded; which means there's a possibility of data loss in case the host or the guest didn't consume any data already present in the vqs. This can be addressed in a later patch series, perhaps in virtio common code. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio: console: Move vq and vq buf removal into separate functionsAmit Shah
This common code will be shared with the PM freeze function. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio: pci: add PM notification handlers for restore, freeze, thaw, poweroffAmit Shah
Handle thaw, restore and freeze notifications from the PM core. Expose these to individual virtio drivers that can quiesce and resume vq operations. For drivers not implementing the thaw() method, use the restore method instead. These functions also save device-specific data so that the device can be put in pre-suspend state after resume, and disable and enable the PCI device in the freeze and resume functions, respectively. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio: pci: switch to new PM APIAmit Shah
The older PM API doesn't have a way to get notifications on hibernate events. Switch to the newer one that gives us those notifications. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio_blk: fix config handler raceMichael S. Tsirkin
Fix a theoretical race related to config work handler: a config interrupt might happen after we flush config work but before we reset the device. It will then cause the config work to run during or after reset. Two problems with this: - if this runs after device is gone we will get use after free - access of config while reset is in progress is racy (as layout is changing). As a solution 1. flush after reset when we know there will be no more interrupts 2. add a flag to disable config access before reset Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio: add debugging if driver doesn't kick.Rusty Russell
Under the existing #ifdef DEBUG, check that they don't have more than 1/10 of a second between an add_buf() and a virtqueue_notify()/virtqueue_kick_prepare() call. We could get false positives on a really busy system, but good for development. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio: expose added descriptors immediately.Rusty Russell
A virtio driver does virtqueue_add_buf() multiple times before finally calling virtqueue_kick(); previously we only exposed the added buffers in the virtqueue_kick() call. This means we don't need a memory barrier in virtqueue_add_buf(), but it reduces concurrency as the device (ie. host) can't see the buffers until the kick. In the unusual (but now possible) case where a driver does add_buf() and get_buf() without doing a kick, we do need to insert one before our counter wraps. Otherwise we could wrap num_added, and later on not realize that we have passed the marker where we should have kicked. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio: avoid modulus operation.Rusty Russell
Since we know vq->vring.num is a power of 2, modulus is lazy (it's asserted in vring_new_virtqueue()). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio: support unlocked queue kickRusty Russell
Based on patch by Christoph for virtio_blk speedup: Split virtqueue_kick to be able to do the actual notification outside the lock protecting the virtqueue. This patch was originally done by Stefan Hajnoczi, but I can't find the original one anymore and had to recreated it from memory. Pointers to the original or corrections for the commit message are welcome. Stefan's patch was here: https://github.com/stefanha/linux/commit/a6d06644e3a58e57a774e77d7dc34c4a5a2e7496 http://www.spinics.net/lists/linux-virtualization/msg14616.html Third time's the charm! Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12virtio: rename virtqueue_add_buf_gfp to virtqueue_add_bufRusty Russell
Remove wrapper functions. This makes the allocation type explicit in all callers; I used GPF_KERNEL where it seemed obvious, left it at GFP_ATOMIC otherwise. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Reviewed-by: Christoph Hellwig <hch@lst.de>
2012-01-12virtio: document functions better.Rusty Russell
The old documentation is left over from when we used a structure with strategy pointers. And move the documentation to the C file as per kernel practice. Though I disagree... Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Reviewed-by: Christoph Hellwig <hch@lst.de>