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path: root/drivers/char/ftape
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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)
2006-10-04Remove all inclusions of <linux/config.h>Dave Jones
kbuild explicitly includes this at build time. Signed-off-by: Dave Jones <davej@redhat.com>
2006-07-03[PATCH] make more file_operation structs staticArjan van de Ven
Mark the static struct file_operations in drivers/char as const. Making them const prevents accidental bugs, and moves them to the .rodata section so that they no longer do any false sharing; in addition with the proper debug option they are then protected against corruption.. [akpm@osdl.org: build fix] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-02[PATCH] irq-flags: drivers/char: Use the new IRQF_ constantsThomas Gleixner
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>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-26[PATCH] devfs: Remove the devfs_fs_kernel.h file from the treeGreg Kroah-Hartman
Also fixes up all files that #include it. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26[PATCH] devfs: Remove devfs_remove() function from the kernel treeGreg Kroah-Hartman
Removes the devfs_remove() function and all callers of it. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26[PATCH] devfs: Remove devfs_mk_cdev() function from the kernel treeGreg Kroah-Hartman
Removes the devfs_mk_cdev() function and all callers of it. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-26drivers/char/ftape/lowlevel/fdc-io.c: Correct a commentBastien Roucaries
This patch correct a comment about cli(). Signed-off-by: Bastien Roucaries <roucaries.bastien@gmail.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-01-15ftape: remove some outdated information from Kconfig filesAdrian Bunk
This patch removes some outdated information about the ftape driver like pointers to no longer existing webpages from Kconfig files. Signed-off-by: Adrian Bunk <bunk@stusta.de>
2005-11-08drivers/char/ftape/lowlevel/ftape-buffer.c should #include ↵Adrian Bunk
"../lowlevel/ftape-buffer.h" Every file should #include the headers containing the prototypes for it's global functions. Signed-off-by: Adrian Bunk <bunk@stusta.de>
2005-10-28[PATCH] Driver Core: fix up all callers of class_device_create()Greg Kroah-Hartman
The previous patch adding the ability to nest struct class_device changed the paramaters to the call class_device_create(). This patch fixes up all in-kernel users of the function. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-10[PATCH] drivers/char: fix-up schedule_timeout() usageNishanth Aravamudan
Use schedule_timeout_interruptible() instead of set_current_state()/schedule_timeout() to reduce kernel size. Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25[PATCH] printk: drivers/char/ftape/compressor/zftape-compress.cDomen Puncer
printk() calls should include appropriate KERN_* constant. Signed-off-by: Christophe Lucas <clucas@rotomalug.org> Signed-off-by: Domen Puncer <domen@coderock.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-20[PATCH] class: convert drivers/char/* to use the new class api instead of ↵gregkh@suse.de
class_simple Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!