On 4/17/23 07:19, Peter Zijlstra wrote:
On Wed, Apr 12, 2023 at 03:59:05AM +0000, John Stultz wrote:
Apparently despite it being marked inline, the compiler
may not inline __down_read_common() which makes it difficult
to identify the cause of lock contention, as the blocked
function will always be listed as __down_read_common().
So this patch adds __always_inline annotation to the
function to force it to be inlines so the calling function
will be listed.
I'm a wee bit confused; what are you looking at? Wchan? What is stopping
the compiler from now handing you
__down_read{,_interruptible,_killable}() instead? Is that fine?
My theory is that the compiler may refuse to inline __down_read_common()
because it is called 3 times in order to reduce overall code size. The
other __down_read*() functions you listed are only called once.
My 2 cents.
Cheers,
Longman
