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| author | Lorenzo Stoakes <lorenzo.stoakes@oracle.com> | 2024-09-11 18:51:11 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2024-09-11 11:07:47 -0700 |
| commit | 7c6a3a65ace70f12b27b1a27c9a69cb791dc6e91 (patch) | |
| tree | beea04da4d4a5672024b89537324908e26ff7094 /drivers/staging | |
| parent | 8d8d276ba2fb5f9ac4984f5c10ae60858090babc (diff) | |
| download | lwn-7c6a3a65ace70f12b27b1a27c9a69cb791dc6e91.tar.gz lwn-7c6a3a65ace70f12b27b1a27c9a69cb791dc6e91.zip | |
minmax: reduce min/max macro expansion in atomisp driver
Avoid unnecessary nested min()/max() which results in egregious macro
expansion.
Use clamp_t() as this introduces the least possible expansion, and turn
the {s,u}DIGIT_FITTING() macros into inline functions to avoid the
nested expansion.
This resolves an issue with slackware 15.0 32-bit compilation as
reported by Richard Narron.
Presumably the min/max fixups would be difficult to backport, this patch
should be easier and fix's Richard's problem in 5.15.
Reported-by: Richard Narron <richard@aaazen.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Closes: https://lore.kernel.org/all/4a5321bd-b1f-1832-f0c-cea8694dc5aa@aaazen.com/
Fixes: 867046cc7027 ("minmax: relax check to allow comparison between unsigned arguments and signed constants")
Cc: stable@vger.kernel.org
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/staging')
| -rw-r--r-- | drivers/staging/media/atomisp/pci/sh_css_frac.h | 26 |
1 files changed, 19 insertions, 7 deletions
diff --git a/drivers/staging/media/atomisp/pci/sh_css_frac.h b/drivers/staging/media/atomisp/pci/sh_css_frac.h index b90b5b330dfa..8ba65161f7a9 100644 --- a/drivers/staging/media/atomisp/pci/sh_css_frac.h +++ b/drivers/staging/media/atomisp/pci/sh_css_frac.h @@ -32,12 +32,24 @@ #define uISP_VAL_MAX ((unsigned int)((1 << uISP_REG_BIT) - 1)) /* a:fraction bits for 16bit precision, b:fraction bits for ISP precision */ -#define sDIGIT_FITTING(v, a, b) \ - min_t(int, max_t(int, (((v) >> sSHIFT) >> max(sFRACTION_BITS_FITTING(a) - (b), 0)), \ - sISP_VAL_MIN), sISP_VAL_MAX) -#define uDIGIT_FITTING(v, a, b) \ - min((unsigned int)max((unsigned)(((v) >> uSHIFT) \ - >> max((int)(uFRACTION_BITS_FITTING(a) - (b)), 0)), \ - uISP_VAL_MIN), uISP_VAL_MAX) +static inline int sDIGIT_FITTING(int v, int a, int b) +{ + int fit_shift = sFRACTION_BITS_FITTING(a) - b; + + v >>= sSHIFT; + v >>= fit_shift > 0 ? fit_shift : 0; + + return clamp_t(int, v, sISP_VAL_MIN, sISP_VAL_MAX); +} + +static inline unsigned int uDIGIT_FITTING(unsigned int v, int a, int b) +{ + int fit_shift = uFRACTION_BITS_FITTING(a) - b; + + v >>= uSHIFT; + v >>= fit_shift > 0 ? fit_shift : 0; + + return clamp_t(unsigned int, v, uISP_VAL_MIN, uISP_VAL_MAX); +} #endif /* __SH_CSS_FRAC_H */ |