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test/ring: remove excessive inlining
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[ upstream commit 981a025 ]

Forcing inlining in test_ring_enqueue and test_ring_dequeue can cause
the compiled code to grow extensively when compiled with no optimization
(-O0 or -Og). This is default in the meson's debug configuration. This
can collide with compiler bugs and cause issues during linking of unit
tests where the api_type or esize are non-const variables causing
inlining cascade. In perf tests this is not the case in perf-tests as
esize and api_type are const values.

One such case was discovered when porting DPDK to RISC-V. GCC 11.2 (and
no fix still in 12.1) is generating a short relative jump instruction
(J <offset>) for goto and for loops. When loop body grows extensively in
ring test, the target offset goes beyond supported offfset of +/- 1MB
from PC. This is an obvious bug in the GCC as RISC-V has a
two-instruction construct to jump to any absolute address (AUIPC+JALR).

However there is no reason to force inlining as the test code works
perfectly fine without it.

GCC has a bug report for a similar case (with conditionals):
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93062

Fixes: a9fe152 ("test/ring: add custom element size functional tests")

Signed-off-by: Stanislaw Kardach <kda@semihalf.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
Acked-by: Konstantin Ananyev <konstantin.v.ananyev@yandex.ru>
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semihalf-kardach-stanislaw authored and kevintraynor committed Jun 8, 2022
1 parent 8ce6cfe commit 3ec90e3
Showing 1 changed file with 3 additions and 3 deletions.
6 changes: 3 additions & 3 deletions app/test/test_ring.h
Expand Up @@ -97,7 +97,7 @@ test_ring_copy_from(struct rte_ring_zc_data *zcd, void *dst, int esize,
}
}

static __rte_always_inline unsigned int
static inline unsigned int
test_ring_enqueue(struct rte_ring *r, void **obj, int esize, unsigned int n,
unsigned int api_type)
{
Expand Down Expand Up @@ -158,7 +158,7 @@ test_ring_enqueue(struct rte_ring *r, void **obj, int esize, unsigned int n,
}
}

static __rte_always_inline unsigned int
static inline unsigned int
test_ring_dequeue(struct rte_ring *r, void **obj, int esize, unsigned int n,
unsigned int api_type)
{
Expand Down Expand Up @@ -222,7 +222,7 @@ test_ring_dequeue(struct rte_ring *r, void **obj, int esize, unsigned int n,
/* This function is placed here as it is required for both
* performance and functional tests.
*/
static __rte_always_inline void *
static inline void *
test_ring_calloc(unsigned int rsize, int esize)
{
unsigned int sz;
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