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* IRQ: Maintain regs pointer globally rather than passing to IRQ handlersDavid Howells2006-10-051-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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)
* [PATCH] MBCS: Use SEEK_{SET, CUR, END} instead of hardcoded valuesJosef 'Jeff' Sipek2006-10-011-3/+4
| | | | | | | | MBCS: Use SEEK_{SET,CUR,END} instead of hardcoded values Signed-off-by: Josef 'Jeff' Sipek <jeffpc@josefsipek.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] irq-flags: drivers/char: Use the new IRQF_ constantsThomas Gleixner2006-07-021-3/+3
| | | | | | | | | Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "David S. Miller" <davem@davemloft.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Remove obsolete #include <linux/config.h>Jörn Engel2006-06-301-1/+0
| | | | | Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* [IA64] mbcs_init() should give up unless running on sn2Greg Edwards2005-10-041-0/+3
| | | | | | | | | | CONFIG_SGI_MBCS is enabled in generic kernels, but the driver may oops some other platforms. Check whether we are running on sn2 and bail out if we are not before doing anything dangerous. Acked-by: Bruce Losure <blosure@americas.sgi.com> Signed-off-by: Greg Edwards <edwardsg@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
* [PATCH] drivers: convert kcalloc to kzallocPekka Enberg2005-09-071-1/+1
| | | | | | | | This patch converts kcalloc(1, ...) calls to use the new kzalloc() function. Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Driver Core: drivers/base - drivers/i2c/chips/adm1026.c: update ↵Yani Ioannou2005-06-201-2/+2
| | | | | | | device attribute callbacks Signed-off-by: Yani Ioannou <yani.ioannou@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] mbcs trivial user annotationsAl Viro2005-05-041-2/+2
| | | | | Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [IA64-SGI] Bus driver for the CX port of SGI's TIO chip.Bruce Losure2005-04-251-0/+849
This patch is to provide CX port infrastructure for SGI TIO-based h/w. Also a 'core services' driver for SGI FPGA-based h/w. Signed-off-by: Bruce Losure <blosure@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>