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| author | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2016-08-19 14:19:30 +0200 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2016-08-24 21:04:48 +0800 |
| commit | 39457acda9139bb078d1b8f974651a194a397060 (patch) | |
| tree | 0cca90b5a8f3a511d3edbc01f691ff5a168e3571 /crypto/xor.c | |
| parent | ed0bd721c9322e8e6ee953884706080d40106a6e (diff) | |
| download | linux-39457acda9139bb078d1b8f974651a194a397060.tar.gz linux-39457acda9139bb078d1b8f974651a194a397060.tar.bz2 linux-39457acda9139bb078d1b8f974651a194a397060.zip | |
crypto: xor - skip speed test if the xor function is selected automatically
If the architecture selected the xor function with XOR_SELECT_TEMPLATE
the speed result of the do_xor_speed benchmark is of limited value.
The speed measurement increases the bootup time a little, which can
makes a difference for kernels used in container like virtual machines.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'crypto/xor.c')
| -rw-r--r-- | crypto/xor.c | 40 |
1 files changed, 19 insertions, 21 deletions
diff --git a/crypto/xor.c b/crypto/xor.c index 35d6b3adf230..b8975d92cd94 100644 --- a/crypto/xor.c +++ b/crypto/xor.c @@ -109,6 +109,18 @@ calibrate_xor_blocks(void) void *b1, *b2; struct xor_block_template *f, *fastest; + fastest = NULL; + +#ifdef XOR_SELECT_TEMPLATE + fastest = XOR_SELECT_TEMPLATE(fastest); + if (fastest) { + printk(KERN_INFO "xor: automatically using best " + "checksumming function %-10s\n", + fastest->name); + goto out; + } +#endif + /* * Note: Since the memory is not actually used for _anything_ but to * test the XOR speed, we don't really want kmemcheck to warn about @@ -126,36 +138,22 @@ calibrate_xor_blocks(void) * all the possible functions, just test the best one */ - fastest = NULL; - -#ifdef XOR_SELECT_TEMPLATE - fastest = XOR_SELECT_TEMPLATE(fastest); -#endif - #define xor_speed(templ) do_xor_speed((templ), b1, b2) - if (fastest) { - printk(KERN_INFO "xor: automatically using best " - "checksumming function:\n"); - xor_speed(fastest); - goto out; - } else { - printk(KERN_INFO "xor: measuring software checksum speed\n"); - XOR_TRY_TEMPLATES; - fastest = template_list; - for (f = fastest; f; f = f->next) - if (f->speed > fastest->speed) - fastest = f; - } + printk(KERN_INFO "xor: measuring software checksum speed\n"); + XOR_TRY_TEMPLATES; + fastest = template_list; + for (f = fastest; f; f = f->next) + if (f->speed > fastest->speed) + fastest = f; printk(KERN_INFO "xor: using function: %s (%d.%03d MB/sec)\n", fastest->name, fastest->speed / 1000, fastest->speed % 1000); #undef xor_speed - out: free_pages((unsigned long)b1, 2); - +out: active_template = fastest; return 0; } |