kernel.git/arch/sh/kernel/cpu/sh4/fpu.c, branch master

signal: Remove task parameter from force_sig

2019-05-27T14:36:28Z

All of the remaining callers pass current into force_sig so remove the task parameter to make this obvious and to make misuse more difficult in the future. This also makes it clear force_sig passes current into force_sig_info. Signed-off-by: "Eric W. Biederman"

sh: sh4: convert to SPDX identifiers

2018-12-28T20:11:45Z

Update license to use SPDX-License-Identifier instead of verbose license text, excepting ${LINUX}/arch/sh/kernel/cpu/sh4/softfloat.c which is not GPL license Link: http://lkml.kernel.org/r/87a7lkcsya.wl-kuninori.morimoto.gx@renesas.com Signed-off-by: Kuninori Morimoto Reviewed-by: Simon Horman Cc: Rich Felker Cc: Yoshinori Sato Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

sched/headers: Move task_struct::signal and task_struct::sighand types and accessors into

2017-03-03T00:43:37Z

task_struct::signal and task_struct::sighand are pointers, which would normally make it straightforward to not define those types in sched.h. That is not so, because the types are accompanied by a myriad of APIs (macros and inline functions) that dereference them. Split the types and the APIs out of sched.h and move them into a new header, . With this change sched.h does not know about 'struct signal' and 'struct sighand' anymore, trying to put accessors into sched.h as a test fails the following way: ./include/linux/sched.h: In function ‘test_signal_types’: ./include/linux/sched.h:2461:18: error: dereferencing pointer to incomplete type ‘struct signal_struct’ ^ This reduces the size and complexity of sched.h significantly. Update all headers and .c code that relied on getting the signal handling functionality from to include . The list of affected files in the preparatory patch was partly generated by grepping for the APIs, and partly by doing coverage build testing, both all[yes|mod|def|no]config builds on 64-bit and 32-bit x86, and an array of cross-architecture builds. Nevertheless some (trivial) build breakage is still expected related to rare Kconfig combinations and in-flight patches to various kernel code, but most of it should be handled by this patch. Acked-by: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

sh: fix up fallout from system.h disintegration.

2012-03-30T10:29:57Z

Quite a bit of fallout all over the place, nothing terribly exciting. Signed-off-by: Paul Mundt

Disintegrate asm/system.h for SH

2012-03-28T17:30:03Z

Disintegrate asm/system.h for SH. Signed-off-by: David Howells cc: linux-sh@vger.kernel.org

sh: Move over to dynamically allocated FPU context.

2010-01-13T03:51:40Z

This follows the x86 xstate changes and implements a task_xstate slab cache that is dynamically sized to match one of hard FP/soft FP/FPU-less. This also tidies up and consolidates some of the SH-2A/SH-4 FPU fragmentation. Now fpu state restorers are commonly defined, with the init_fpu()/fpu_init() mess reworked to follow the x86 convention. The fpu_init() register initialization has been replaced by xstate setup followed by writing out to hardware via the standard restore path. As init_fpu() now performs a slab allocation a secondary lighterweight restorer is also introduced for the context switch. In the future the DSP state will be rolled in here, too. More work remains for math emulation and the SH-5 FPU, which presently uses its own special (UP-only) interfaces. Signed-off-by: Paul Mundt

sh: Minor optimisations to FPU handling

2009-11-24T08:45:38Z

A number of small optimisations to FPU handling, in particular: - move the task USEDFPU flag from the thread_info flags field (which is accessed asynchronously to the thread) to a new status field, which is only accessed by the thread itself. This allows locking to be removed in most cases, or can be reduced to a preempt_lock(). This mimics the i386 behaviour. - move the modification of regs->sr and thread_info->status flags out of save_fpu() to __unlazy_fpu(). This gives the compiler a better chance to optimise things, as well as making save_fpu() symmetrical with restore_fpu() and init_fpu(). - implement prepare_to_copy(), so that when creating a thread, we can unlazy the FPU prior to copying the thread data structures. Also make sure that the FPU is disabled while in the kernel, in particular while booting, and for newly created kernel threads, In a very artificial benchmark, the execution time for 2500000 context switches was reduced from 50 to 45 seconds. Signed-off-by: Stuart Menefy Signed-off-by: Paul Mundt

sh: add sleazy FPU optimization

2009-11-24T07:23:38Z

sh port of the sLeAZY-fpu feature currently implemented for some architectures such us i386. Right now the SH kernel has a 100% lazy fpu behaviour. This is of course great for applications that have very sporadic or no FPU use. However for very frequent FPU users... you take an extra trap every context switch. The patch below adds a simple heuristic to this code: after 5 consecutive context switches of FPU use, the lazy behavior is disabled and the context gets restored every context switch. After 256 switches, this is reset and the 100% lazy behavior is returned. Tests with LMbench showed no regression. I saw a little improvement due to the prefetching (~2%). The tests below also show that, with this sLeazy patch, indeed, the number of FPU exceptions is reduced. To test this. I hacked the lat_ctx LMBench to use the FPU a little more. sLeasy implementation =========================================== switch_to calls | 79326 sleasy calls | 42577 do_fpu_state_restore calls| 59232 restore_fpu calls | 59032 Exceptions: 0x800 (FPU disabled ): 16604 100% Leazy (default implementation) =========================================== switch_to calls | 79690 do_fpu_state_restore calls | 53299 restore_fpu calls | 53101 Exceptions: 0x800 (FPU disabled ): 53273 Signed-off-by: Giuseppe Cavallaro Signed-off-by: Stuart Menefy Signed-off-by: Paul Mundt

sh: fcnvds fix with denormalized numbers on SH-4 FPU.

2009-01-29T02:56:02Z

This fixes a bug in the FPU exception handler for the FCNVDS instruction. To get the register number the instruction is shifted right by 9, though it should be shifted right by 8. More information at ST Linux bugzilla: https://bugzilla.stlinux.com/show_bug.cgi?id=4892 Signed-off-by: Giuseppe Di Giore Signed-off-by: Carmelo Amoroso Signed-off-by: Stuart Menefy Signed-off-by: Paul Mundt

sh: Subnormal double to float conversion

2008-09-08T01:35:05Z

This patch adds support for the SH4 to convert a subnormal double into a float by catching the FPE and implementing the FCNVDS instruction in software. Signed-off-by: Carl Shaw Signed-off-by: Paul Mundt