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| author | Huacai Chen <chenhc@lemote.com> | 2014-08-11 17:10:38 +0800 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2014-08-19 18:04:24 +0200 |
| commit | bfcdf1306361951b104c6858d07f6778b53e4368 (patch) | |
| tree | 9752e9f37fe001dd624b082a651e8a0bf0c2e25d | |
| parent | bbbf6d8768f5cac3523c408917083a111b1f3ffe (diff) | |
| download | linux-bfcdf1306361951b104c6858d07f6778b53e4368.tar.gz linux-bfcdf1306361951b104c6858d07f6778b53e4368.tar.bz2 linux-bfcdf1306361951b104c6858d07f6778b53e4368.zip | |
MIPS: Loongson: Fix COP2 usage for preemptible kernel
In preemptible kernel, only TIF_USEDFPU flag is reliable to distinguish
whether _init_fpu()/_restore_fp() is needed. Because the value of the
CP0_Status.CU1 isn't changed during preemption.
V2: Fix coding style.
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/7515/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| -rw-r--r-- | arch/mips/loongson/loongson-3/cop2-ex.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/arch/mips/loongson/loongson-3/cop2-ex.c b/arch/mips/loongson/loongson-3/cop2-ex.c index 9182e8d2967c..b03e37d2071a 100644 --- a/arch/mips/loongson/loongson-3/cop2-ex.c +++ b/arch/mips/loongson/loongson-3/cop2-ex.c @@ -22,13 +22,13 @@ static int loongson_cu2_call(struct notifier_block *nfb, unsigned long action, void *data) { - int fpu_enabled; + int fpu_owned; int fr = !test_thread_flag(TIF_32BIT_FPREGS); switch (action) { case CU2_EXCEPTION: preempt_disable(); - fpu_enabled = read_c0_status() & ST0_CU1; + fpu_owned = __is_fpu_owner(); if (!fr) set_c0_status(ST0_CU1 | ST0_CU2); else @@ -39,8 +39,8 @@ static int loongson_cu2_call(struct notifier_block *nfb, unsigned long action, KSTK_STATUS(current) |= ST0_FR; else KSTK_STATUS(current) &= ~ST0_FR; - /* If FPU is enabled, we needn't init or restore fp */ - if(!fpu_enabled) { + /* If FPU is owned, we needn't init or restore fp */ + if (!fpu_owned) { set_thread_flag(TIF_USEDFPU); if (!used_math()) { _init_fpu(); |