lkml.org 
[lkml]   [2022]   [Jun]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 4.14 191/237] random: avoid checking crng_ready() twice in random_init()
    Date
    From: "Jason A. Donenfeld" <Jason@zx2c4.com>

    commit 9b29b6b20376ab64e1b043df6301d8a92378e631 upstream.

    The current flow expands to:

    if (crng_ready())
    ...
    else if (...)
    if (!crng_ready())
    ...

    The second crng_ready() call is redundant, but can't so easily be
    optimized out by the compiler.

    This commit simplifies that to:

    if (crng_ready()
    ...
    else if (...)
    ...

    Fixes: 560181c27b58 ("random: move initialization functions out of hot pages")
    Cc: stable@vger.kernel.org
    Cc: Dominik Brodowski <linux@dominikbrodowski.net>
    Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    ---
    drivers/char/random.c | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    --- a/drivers/char/random.c
    +++ b/drivers/char/random.c
    @@ -834,7 +834,7 @@ int __init random_init(const char *comma
    if (crng_ready())
    crng_reseed();
    else if (trust_cpu)
    - credit_init_bits(arch_bytes * 8);
    + _credit_init_bits(arch_bytes * 8);

    return 0;
    }

    \
     
     \ /
      Last update: 2022-06-23 19:43    [W:2.746 / U:0.044 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site