As the comment explains, the if check ensures that the divisor oa_period is a u32. Explicitly cast oa_period to u32 to remove the following Coccinelle/coccicheck warning reported by do_div.cocci: WARNING: do_div() does a 64-by-32 division, please consider using div64_u64 instead Use the preferred div_u64() function instead of the do_div() macro and remove the now unnecessary local variable tmp. Inline the if/else and invert the conditional expression. Reviewed-by: Jonathan Cavitt <jonathan.cavitt@xxxxxxxxx> Signed-off-by: Thorsten Blum <thorsten.blum@xxxxxxxxxx> --- Changes in v2: - Use div_u64() instead of do_div() after feedback from Ville Syrjälä - Link to v1: https://lore.kernel.org/linux-kernel/20240710074650.419902-2-thorsten.blum@xxxxxxxxxx/ Changes in v3: - Inline if/else as suggested by Jonathan Cavitt and Andi Shyti - Link to v2: https://lore.kernel.org/linux-kernel/20240802160323.46518-2-thorsten.blum@xxxxxxxxxx/ --- drivers/gpu/drm/i915/i915_perf.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c index 025a79fe5920..6ff905d2b78f 100644 --- a/drivers/gpu/drm/i915/i915_perf.c +++ b/drivers/gpu/drm/i915/i915_perf.c @@ -4063,17 +4063,13 @@ static int read_properties_unlocked(struct i915_perf *perf, oa_period = oa_exponent_to_ns(perf, value); /* This check is primarily to ensure that oa_period <= - * UINT32_MAX (before passing to do_div which only + * UINT32_MAX (before passing it to div_u64 which only * accepts a u32 denominator), but we can also skip * checking anything < 1Hz which implicitly can't be * limited via an integer oa_max_sample_rate. */ - if (oa_period <= NSEC_PER_SEC) { - u64 tmp = NSEC_PER_SEC; - do_div(tmp, oa_period); - oa_freq_hz = tmp; - } else - oa_freq_hz = 0; + oa_freq_hz = oa_period > NSEC_PER_SEC ? 0 : + div_u64(NSEC_PER_SEC, (u32)oa_period); if (oa_freq_hz > i915_oa_max_sample_rate && !perfmon_capable()) { drm_dbg(&perf->i915->drm, -- 2.45.2
