From: "Jason A. Donenfeld" Jason@zx2c4.com
commit 7b87324112df2e1f9b395217361626362dcfb9fb upstream.
Rather than an awkward combination of ifdefs and __maybe_unused, we can ensure more source gets parsed, regardless of the configuration, by using IS_ENABLED for the CONFIG_NUMA conditional code. This makes things cleaner and easier to follow.
I've confirmed that on !CONFIG_NUMA, we don't wind up with excess code by accident; the generated object file is the same.
Reviewed-by: 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 | 32 ++++++++++++-------------------- 1 file changed, 12 insertions(+), 20 deletions(-)
--- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -760,7 +760,6 @@ static int credit_entropy_bits_safe(stru
static DECLARE_WAIT_QUEUE_HEAD(crng_init_wait);
-#ifdef CONFIG_NUMA /* * Hack to deal with crazy userspace progams when they are all trying * to access /dev/urandom in parallel. The programs are almost @@ -768,7 +767,6 @@ static DECLARE_WAIT_QUEUE_HEAD(crng_init * their brain damage. */ static struct crng_state **crng_node_pool __read_mostly; -#endif
static void invalidate_batched_entropy(void); static void numa_crng_init(void); @@ -816,7 +814,7 @@ static bool __init crng_init_try_arch_ea return arch_init; }
-static void __maybe_unused crng_initialize_secondary(struct crng_state *crng) +static void crng_initialize_secondary(struct crng_state *crng) { memcpy(&crng->state[0], "expand 32-byte k", 16); _get_random_bytes(&crng->state[4], sizeof(__u32) * 12); @@ -867,7 +865,6 @@ static void crng_finalize_init(struct cr } }
-#ifdef CONFIG_NUMA static void do_numa_crng_init(struct work_struct *work) { int i; @@ -894,29 +891,24 @@ static DECLARE_WORK(numa_crng_init_work,
static void numa_crng_init(void) { - schedule_work(&numa_crng_init_work); + if (IS_ENABLED(CONFIG_NUMA)) + schedule_work(&numa_crng_init_work); }
static struct crng_state *select_crng(void) { - struct crng_state **pool; - int nid = numa_node_id(); - - /* pairs with cmpxchg_release() in do_numa_crng_init() */ - pool = READ_ONCE(crng_node_pool); - if (pool && pool[nid]) - return pool[nid]; - - return &primary_crng; -} -#else -static void numa_crng_init(void) {} + if (IS_ENABLED(CONFIG_NUMA)) { + struct crng_state **pool; + int nid = numa_node_id(); + + /* pairs with cmpxchg_release() in do_numa_crng_init() */ + pool = READ_ONCE(crng_node_pool); + if (pool && pool[nid]) + return pool[nid]; + }
-static struct crng_state *select_crng(void) -{ return &primary_crng; } -#endif
/* * crng_fast_load() can be called by code in the interrupt service