diff options
| author | Samuel Holland <[email protected]> | 2025-02-20 10:42:28 -0800 |
|---|---|---|
| committer | Anup Patel <[email protected]> | 2025-03-24 17:56:05 +0530 |
| commit | 6b97950cf5d51afcfd8d059a0d8baa15601e55ab (patch) | |
| tree | 05c16a6d5bf7ea315775c830536639111b4868ed | |
| parent | ef4ed2dda76648171d551537443a16b5db712284 (diff) | |
lib: sbi_scratch: Optimize hartid and scratch lookup
The compiler generates much better code for sbi_hartindex_to_hartid()
and sbi_hartindex_to_scratch() when using a constant for the bounds
check. This works out nicely because the underlying arrays are already
a constant size, so the only change needed is to fill the remainder of
each array with the appropriate default/out-of-bounds value. The
ellipsis in the designated initializer is a GCC extension (also
supported by Clang), but avoids runtime initialization of the array.
Signed-off-by: Samuel Holland <[email protected]>
Reviewed-by: Anup Patel <[email protected]>
| -rw-r--r-- | include/sbi/sbi_scratch.h | 6 | ||||
| -rw-r--r-- | lib/sbi/sbi_scratch.c | 4 |
2 files changed, 5 insertions, 5 deletions
diff --git a/include/sbi/sbi_scratch.h b/include/sbi/sbi_scratch.h index 0d188d12..1ec1710e 100644 --- a/include/sbi/sbi_scratch.h +++ b/include/sbi/sbi_scratch.h @@ -226,7 +226,7 @@ extern u32 hartindex_to_hartid_table[]; /** Get sbi_scratch from HART index */ #define sbi_hartindex_to_hartid(__hartindex) \ ({ \ - ((__hartindex) <= sbi_scratch_last_hartindex()) ?\ + ((__hartindex) < SBI_HARTMASK_MAX_BITS) ? \ hartindex_to_hartid_table[__hartindex] : -1U; \ }) @@ -236,8 +236,8 @@ extern struct sbi_scratch *hartindex_to_scratch_table[]; /** Get sbi_scratch from HART index */ #define sbi_hartindex_to_scratch(__hartindex) \ ({ \ - ((__hartindex) <= sbi_scratch_last_hartindex()) ?\ - hartindex_to_scratch_table[__hartindex] : NULL;\ + ((__hartindex) < SBI_HARTMASK_MAX_BITS) ? \ + hartindex_to_scratch_table[__hartindex] : NULL; \ }) /** diff --git a/lib/sbi/sbi_scratch.c b/lib/sbi/sbi_scratch.c index 5a9e935b..e1cc5658 100644 --- a/lib/sbi/sbi_scratch.c +++ b/lib/sbi/sbi_scratch.c @@ -15,8 +15,8 @@ #include <sbi/sbi_string.h> u32 last_hartindex_having_scratch = 0; -u32 hartindex_to_hartid_table[SBI_HARTMASK_MAX_BITS] = { -1U }; -struct sbi_scratch *hartindex_to_scratch_table[SBI_HARTMASK_MAX_BITS] = { 0 }; +u32 hartindex_to_hartid_table[SBI_HARTMASK_MAX_BITS] = { [0 ... SBI_HARTMASK_MAX_BITS-1] = -1U }; +struct sbi_scratch *hartindex_to_scratch_table[SBI_HARTMASK_MAX_BITS]; static spinlock_t extra_lock = SPIN_LOCK_INITIALIZER; static unsigned long extra_offset = SBI_SCRATCH_EXTRA_SPACE_OFFSET; |