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Groups > linux.kernel > #1547778
| From | Stephan Müller <smueller@chronox.de> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | [PATCH 4/8] random: remove unused branch in hot code path |
| Date | 2016-12-27 23:50 +0100 |
| Message-ID | <sT8Jb-86X-5@gated-at.bofh.it> (permalink) |
| References | <sT8Jb-86X-3@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
The variable ip is defined to be a __u64 which is always 8 bytes on any architecture. Thus, the check for sizeof(ip) > 4 will always be true. As the check happens in a hot code path, remove the branch. Signed-off-by: Stephan Mueller <smueller@chronox.de> --- drivers/char/random.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/char/random.c b/drivers/char/random.c index 5c26b1c..8d4d720 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -1136,8 +1136,7 @@ void add_interrupt_randomness(int irq, int irq_flags) fast_pool->pool[1] ^= now ^ c_high; ip = regs ? instruction_pointer(regs) : _RET_IP_; fast_pool->pool[2] ^= ip; - fast_pool->pool[3] ^= (sizeof(ip) > 4) ? ip >> 32 : - get_reg(fast_pool, regs); + fast_pool->pool[3] ^= ip >> 32; fast_mix(fast_pool); add_interrupt_bench(cycles); -- 2.9.3
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[PATCH 4/8] random: remove unused branch in hot code path Stephan Müller <smueller@chronox.de> - 2016-12-27 23:50 +0100
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