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path: root/drivers/scsi/megaraid
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2008-06-20megaraid: BKL pushdownArnd Bergmann
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2008-06-20Add a bunch of cycle_kernel_lock() callsJonathan Corbet
All of the open() functions which don't need the BKL on their face may still depend on its acquisition to serialize opens against driver initialization. So make those functions acquire then release the BKL to be on the safe side. Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-06-20Add "no BKL needed" comments to several driversJonathan Corbet
This documents the fact that somebody looked at the relevant open() functions and concluded that, due to their trivial nature, no locking was needed. Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-05-02[SCSI] megaraid_sas: fix suspend/resume sectionsJiri Slaby
megaraid_sas suspend and resume are inappropriatelly placed in __devinit section. Remove those placements and make the stuff dependent on CONFIG_PM. While at it, mark remove function as __devexit. Signed-off-by: Jiri Slaby <jirislaby@gmail.com> Acked-by: "Yang, Bo" <Bo.Yang@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-29[SCSI] megaraid_sas; Update the Version and Changelogbo yang
Update the Version and Changelog for megaraid_sas Driver Signed-off-by: Bo Yang<bo.yang@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-29[SCSI] megaraid_mbox: fix Dell CERC firmware problemHannes Reinecke
Newer Dell CERC firmware (>= 6.62) implement a random deletion handling compatible with the legacy megaraid driver. The legacy handling shifted the target ID by 0x80 only for I/O commands (READ/WRITE/etc), whereas megaraid_mbox shifts the target ID always if random deletion is supported. The resulted in megaraid_mbox sending an INQUIRY to the wrong channel, and not finding any devices, obviously. So we disable the random deletion support if the offending firmware is found. Addresses http://bugzilla.kernel.org/show_bug.cgi?id=6695 Signed-off-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: "Yang, Bo" <Bo.Yang@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-21Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-2.6: (36 commits) SCSI: convert struct class_device to struct device DRM: remove unused dev_class IB: rename "dev" to "srp_dev" in srp_host structure IB: convert struct class_device to struct device memstick: convert struct class_device to struct device driver core: replace remaining __FUNCTION__ occurrences sysfs: refill attribute buffer when reading from offset 0 PM: Remove destroy_suspended_device() Firmware: add iSCSI iBFT Support PM: Remove legacy PM (fix) Kobject: Replace list_for_each() with list_for_each_entry(). SYSFS: Explicitly include required header file slab.h. Driver core: make device_is_registered() work for class devices PM: Convert wakeup flag accessors to inline functions PM: Make wakeup flags available whenever CONFIG_PM is set PM: Fix misuse of wakeup flag accessors in serial core Driver core: Call device_pm_add() after bus_add_device() in device_add() PM: Handle device registrations during suspend/resume block: send disk "change" event for rescan_partitions() sysdev: detect multiple driver registrations ... Fixed trivial conflict in include/linux/memory.h due to semaphore header file change (made irrelevant by the change to mutex).
2008-04-19SCSI: convert struct class_device to struct deviceTony Jones
It's big, but there doesn't seem to be a way to split it up smaller... Signed-off-by: Tony Jones <tonyj@suse.de> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Cc: Roland Dreier <rolandd@cisco.com> Cc: Sean Hefty <sean.hefty@intel.com> Cc: Hal Rosenstock <hal.rosenstock@gmail.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-18Convert asm/semaphore.h users to linux/semaphore.hMatthew Wilcox
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2008-04-18drivers: Remove unnecessary inclusions of asm/semaphore.hMatthew Wilcox
None of these files use any of the functionality promised by asm/semaphore.h. It's possible that they rely on it dragging in some unrelated header file, but I can't build all these files, so we'll have fix any build failures as they come up. Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2008-04-07[SCSI] megaraid_sas: Add the new controller(1078DE) support to the driverbo yang
Add the new Controller (ID: 007C) support to driver. Signed-off-by Bo Yang<bo.yang@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-07[SCSI] megaraid_sas: Fix the frame count calculationbo yang
When Driver sent wrong frame count to firmware. As this particular command is sent to drive, FW is seeing continuous chip resets and so the command will timeout. Signed-off-by Bo Yang<bo.yang@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-07[SCSI] megaraid_sas: rollback the sense info implementationbo yang
Sense buffer ptr data type in the ioctl path is reverted back to u32 * as in previous versions of driver. Signed-off-by Bo Yang<bo.yang@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-02-11[SCSI] MegaRAID driver management char device moved to miscThomas Horsten
The MegaRAID driver's common management module (megaraid_mm.c) creates a char device used by the management tool "megarc" from LSI Logic (and possibly other management tools). In 2.6 with udev, this device doesn't get created because it is not registered in sysfs. I first fixed this by registering a class "megaraid_mm", but realized that this should probably be moved to misc devices, instead of taking up a char major. This is because only 1 device is used, even if there are multiple adapters - the minor is never used (the adapter info is in the ioctl block sent to the driver, not detected based on the minor number as one might think). So it is a complete waste to have an entire major taken by this. So it now uses a misc device which I named "megadev0" (the name that megarc expects), and has a dynamic minor (previoulsy a dynamic major was used). I have tested this on my own system with the megarc tool, and it works just as fine as before (only now the device gets created correctly by udev). Acked-by: "Patro, Sumant" <Sumant.Patro@lsi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-02-06scsi: megaraid: trivial drop duplicate mutex.h includeDaniel Walker
Signed-off-by: Daniel Walker <dwalker@mvista.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-03drivers/scsi/: Spelling fixesJoe Perches
Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Andrew Vasquez <andrew.vasquez@qlogic.com> Acked-by: James Smart <james.smart@emulex.com> Acked-by: Darrick J. Wong <djwong@us.ibm.com> Acked-by: David Somayajulu <david.somayajulu@qlogic.com> Acked-by: Mark Salyzyn <mark_salyzyn@adaptec.com> Signed-off-by: Adrian Bunk <bunk@kernel.org>
2008-01-30[SCSI] remove use_sg_chainingJames Bottomley
With the sg table code, every SCSI driver is now either chain capable or broken (or has sg_tablesize set so chaining is never activated), so there's no need to have a check in the host template. Also tidy up the code by moving the scatterlist size defines into the SCSI includes and permit the last entry of the scatterlist pools not to be a power of two. Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-23[SCSI] megaraid: fix section mismatchRandy Dunlap
Change megaraid_pci_driver_g variable name so that it matches the modpost whitelist that allows pointers to init text/data. WARNING: vmlinux.o(.data+0x1a8e30): Section mismatch: reference to .init.text:megaraid_probe_one (between 'megaraid_pci_driver_g' and 'class_device_attr_megaraid_mbox_app_hndl') Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11[SCSI] megaraid_sas: Update version and changelogbo yang
Update version and changelog Signed-off-by: Bo Yang <bo.yang@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11[SCSI] megaraid_sas: support for poll_mode_io (reduced interrupt)bo yang
Added module parameter "poll_mode_io" to support for "polling" (reduced interrupt operation). In this mode, IO completion interrupts are delayed. At the end of initiating IOs, the driver schedules for cmd completion if there are pending cmds. A timer-based interrupt has also been added to prevent IO completion from being delayed indefinitely in the case that no new IOs are initiated. Some formatting issues in resume, suspend comment block also corrected Signed-off-by: Bo Yang <bo.yang@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11[SCSI] megaraid_sas: call cmd completion from resetbo yang
Driver will call cmd completion routine from Reset path without waiting for cmd completion from isr context. Signed-off-by: Bo Yang <bo.yang@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11[SCSI] megaraid_sas: use unsigned long for sense_buff ptrbo yang
MegaRAID utilities expect sense_buff to be of type unsigned long. Signed-off-by: Bo Yang <bo.yang@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11[SCSI] megaraid_sas: check max_sgl reported by FW for setting ↵bo yang
max_sectors_per_req 1. Setting the max_sectors_per_req based on max SGL supported by the FW. Prior versions calculated this value from controller info's max_sectors_1, max_sectors_2. For certain controllers/FW, this was resulting in a value greater than max SGL supported by the FW. Now we take the min of max sgl from FW and max_sectors calculation. 2. Increased MFI_POLL_TIMEOUT_SECS to 60 seconds from 10. FW may take a max of 60 seconds to respond to the INIT cmd. Signed-off-by: Bo Yang <bo.yang@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11[SCSI] megaraid_sas: add hibernation supportbo yang
Adding hibernation support. suspend, resume routine implemented. Signed-off-by: Bo Yang <bo.yang@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11[SCSI] megaraid_sas: Convert aen_mutex to the mutex APIMatthias Kaehlcke
Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com> Acked-by: Bo Yang <Bo.Yang@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2007-10-22[SG] Update drivers to use sg helpersJens Axboe
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-19Fix misspellings of "system", "controller", "interrupt" and "necessary".Robert P. J. Day
Fix the various misspellings of "system", controller", "interrupt" and "[un]necessary". Signed-off-by: Robert P. J. Day <rpjday@mindspring.com> Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-16[SCSI] add use_sg_chaining option to scsi_host_templateFUJITA Tomonori
This option is true if a low-level driver can support sg chaining. This will be removed eventually when all the drivers are converted to support sg chaining. q->max_phys_segments is set to SCSI_MAX_SG_SEGMENTS if false. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-19some kmalloc/memset ->kzalloc (tree wide)Yoann Padioleau
Transform some calls to kmalloc/memset to a single kzalloc (or kcalloc). Here is a short excerpt of the semantic patch performing this transformation: @@ type T2; expression x; identifier f,fld; expression E; expression E1,E2; expression e1,e2,e3,y; statement S; @@ x = - kmalloc + kzalloc (E1,E2) ... when != \(x->fld=E;\|y=f(...,x,...);\|f(...,x,...);\|x=E;\|while(...) S\|for(e1;e2;e3) S\) - memset((T2)x,0,E1); @@ expression E1,E2,E3; @@ - kzalloc(E1 * E2,E3) + kcalloc(E1,E2,E3) [akpm@linux-foundation.org: get kcalloc args the right way around] Signed-off-by: Yoann Padioleau <padator@wanadoo.fr> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Acked-by: Russell King <rmk@arm.linux.org.uk> Cc: Bryan Wu <bryan.wu@analog.com> Acked-by: Jiri Slaby <jirislaby@gmail.com> Cc: Dave Airlie <airlied@linux.ie> Acked-by: Roland Dreier <rolandd@cisco.com> Cc: Jiri Kosina <jkosina@suse.cz> Acked-by: Dmitry Torokhov <dtor@mail.ru> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org> Acked-by: Pierre Ossman <drzeus-list@drzeus.cx> Cc: Jeff Garzik <jeff@garzik.org> Cc: "David S. Miller" <davem@davemloft.net> Acked-by: Greg KH <greg@kroah.com> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: "Antonino A. Daplas" <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-14[SCSI] megaraid_mbox: use mutex instead of semaphoreMatthias Kaehlcke
The Megaraid Mailbox driver uses a semaphore as mutex. Use the mutex API instead of the (binary) semaphore. Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com> Acked-by: "Patro, Sumant" <Sumant.Patro@lsi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-05-31[SCSI] megaraid: convert to use the data buffer accessorsFUJITA Tomonori
- remove the unnecessary map_single path. - convert to use the new accessors for the sg lists and the parameters. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Acked-by: Sumant Patro <sumant.patro@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-05-31[SCSI] megaraid_sas: convert to use the data buffer accessorsFUJITA Tomonori
- remove the unnecessary map_single path. - convert to use the new accessors for the sg lists and the parameters. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Acked-by: Sumant Patro <sumant.patro@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-05-29Merge master.kernel.org:/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6Linus Torvalds
* master.kernel.org:/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6: [SCSI] megaraid_sas: intercept cmd timeout and throttle io [SCSI] fusion: Fix |/|| confusion [SCSI] aic94xx: asd_clear_nexus should fail if the cleared task does not complete [SCSI] aic7xxx: fix aicasm build failure with gcc-3.4.6 [SCSI] aacraid: apply commit config for reset_devices flag [SCSI] sd: fix refcounting regression in suspend/resume routines [SCSI] aacraid: fix panic on short Inquiry [SCSI] aacraid: Correct sa platform support. (Was: [Bug 8469] Bad EIP value on pentium3 SMP kernel-2.6.21.1) [SCSI] NCR53C9x: correct spelling mistake in deprecation notice [SCSI] tgt: fix a rdma indirect transfer error bug [SCSI] MegaRAID: Update MAINTAINERS email-id [SCSI] stex: minor cleanup and version update [SCSI] stex: fix reset recovery for console device [SCSI] stex: extend hard reset wait time [SCSI] stex: fix id mapping issue [SCSI] ipr: Proper return codes for eh_dev_reset for SATA devices [SCSI] zfcp: IO stall after deleting and path checker changes after reenabling zfcp devices [SCSI] zfcp: avoid clutter in erp_dbf
2007-05-24[SCSI] megaraid_sas: intercept cmd timeout and throttle ioSumant Patro
eh_timed_out call back (megasas_reset_timer) is used to throttle io to the adapter when it is called the first time for a scmd. The MEGASAS_FW_BUSY flag is set and can_queue reduced to 16. The can_queue is restored from completion routine in following two conditions : 5 seconds has elapsed and the # of outstanding cmds in FW is < 17. Signed-off-by: Sumant Patro <sumant.patro@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-05-21Detach sched.h from mm.hAlexey Dobriyan
First thing mm.h does is including sched.h solely for can_do_mlock() inline function which has "current" dereference inside. By dealing with can_do_mlock() mm.h can be detached from sched.h which is good. See below, why. This patch a) removes unconditional inclusion of sched.h from mm.h b) makes can_do_mlock() normal function in mm/mlock.c c) exports can_do_mlock() to not break compilation d) adds sched.h inclusions back to files that were getting it indirectly. e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were getting them indirectly Net result is: a) mm.h users would get less code to open, read, preprocess, parse, ... if they don't need sched.h b) sched.h stops being dependency for significant number of files: on x86_64 allmodconfig touching sched.h results in recompile of 4083 files, after patch it's only 3744 (-8.3%). Cross-compile tested on all arm defconfigs, all mips defconfigs, all powerpc defconfigs, alpha alpha-up arm i386 i386-up i386-defconfig i386-allnoconfig ia64 ia64-up m68k mips parisc parisc-up powerpc powerpc-up s390 s390-up sparc sparc-up sparc64 sparc64-up um-x86_64 x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig as well as my two usual configs. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-06[SCSI] megaraid: update version reported by MEGAIOC_QDRVRVERDavid Milburn
Update the driver version reported by MEGAIOC_QDRVRVER to match LSI_COMMON_MOD_VERSION. Signed-off-by: David Milburn <dmilburn@redhat.com> Acked-by: "Patro, Sumant" <Sumant.Patro@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-02-16[SCSI] megaraid_sas: update version and author infoSumant Patro
Signed-off-by: Sumant Patro <sumant.patro@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-02-16[SCSI] megaraid_sas: return sync cache call with successSumant Patro
FW does not support SYNCHRONIZE_CACHE cmd. FW flush cache on its own. So, we just return success from the megasas_queue_command. Signed-off-by: Sumant Patro <sumant.patro@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-02-16[SCSI] megaraid_sas: replace pci_alloc_consitent with dma_alloc_coherent in ↵Sumant Patro
ioctl path Replaced pci_alloc_consistent with dma_alloc_coherent from the ioctl path. This is to avoid situations where ioctl fails for lack of memory (when system under heavy stress). Signed-off-by: Sumant Patro <sumant.patro@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-02-16[SCSI] megaraid_sas: add bios_param in scsi_host_templateSumant Patro
Signed-off-by: Sumant Patro <sumant.patro@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-02-16[SCSI] megaraid_sas: do not process cmds if hw_crit_error is setSumant Patro
Checks if hw_crit_error is set. If it is set, we donot process commands. Checks added in megasas_queue_command and command completion routines. Signed-off-by: Sumant Patro <sumant.patro@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-02-12[PATCH] mark struct file_operations const 6Arjan van de Ven
Many struct file_operations in the kernel can be "const". Marking them const moves these to the .rodata section, which avoids false sharing with potential dirty data. In addition it'll catch accidental writes at compile time to these shared resources. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-01-31Merge branch 'linus'James Bottomley
2007-01-13[SCSI] megaraid: more kernel-doc fixesRandy Dunlap
More megaraid kernel-doc fixes. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Acked-by: Sumant Patro <sumantp@lsil.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-01-13[SCSI] megaraid: fix kernel-docRandy Dunlap
kernel-doc modifications: - change "@param var" notation to @var; - change function/description separator from ':' to '-'; - change var/description separator from '-' to ':'; - fix a few doc. typos; - don't use kernel-doc /** lead-in when the doc. block is not kernel-doc; - use Linux common */ ending comment format instead of **/; - use correct function parameter names; - place function parameters immediately after the function short description; - place kernel-doc immediately before its function or macro; Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Acked-by: Sumant Patro <sumantp@lsil.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-01-13[SCSI] megaraid_{mm,mbox}: init fix for kdumpSumant Patro
1. Changes in Initialization to fix kdump failure. Send SYNC command on loading. This command clears the pending commands in the adapter and re-initialize its internal RAID structure. Without this change, megaraid driver either panics or fails to initialize the adapter during kdump's second kernel boot if there are pending commands or interrupts from other devices sharing the same IRQ. 2. Authors email-id domain name changed from lsil.com to lsi.com. Also modified the MODULE_AUTHOR to megaraidlinux@lsi.com Signed-off-by: Sumant Patro <sumant.patro@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-01-06[SCSI] megaraid_sas: Update module authorSumant Patro
Update domain name change from lsil.com to lsi.com. Change module author to megaraidlinux@lsi.com Signed-off-by: Sumant Patro <sumant.patro@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-11-22[SCSI] megaraid_sas: make 2 functions staticAdrian Bunk
This patch makes two needlessly global functions static. Signed-off-by: Adrian Bunk <bunk@stusta.de> Acked-by: "Patro, Sumant" <Sumant.Patro@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-10-16[PATCH] scsi: megaraid_{mm,mbox}: 64-bit DMA capability fixAndrey Mirkin
It is known that 2 LSI Logic MegaRAID SATA RAID Controllers (150-4 and 150-6) don't support 64-bit DMA. Unfortunately currently this check is wrong and driver sets 64-bit DMA mode for these devices. Signed-off-by: Andrey Mirkin <amirkin@sw.ru> Acked-by: Vasily Averin <vvs@sw.ru> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-05IRQ: Maintain regs pointer globally rather than passing to IRQ handlersDavid Howells
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)