\[ \boxed { {\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}y \left ( x \right ) =-{\frac {x\sin \left ( x \right ) {\frac {\rm d}{{\rm d}x}}y \left ( x \right ) }{\cos \left ( x \right ) x-\sin \left ( x \right ) }}+{\frac {y \left ( x \right ) \sin \left ( x \right ) }{\cos \left ( x \right ) x-\sin \left ( x \right ) }}=0} \]
Mathematica: cpu = 1.249159 (sec), leaf count = 46 \[ \text {DSolve}\left [y''(x)=\frac {y(x) \sin (x)}{x \cos (x)-\sin (x)}-\frac {x \sin (x) y'(x)}{x \cos (x)-\sin (x)},y(x),x\right ] \]
Maple: cpu = 13.588 (sec), leaf count = 60 \[ \left \{ y \left ( x \right ) ={\it \_C1}\,\sin \left ( x \right ) +{\it \_C2}\,\sin \left ( x \right ) \int \!{{\rm e}^{\int \!{\frac {-2\, \left ( \cos \left ( x \right ) \right ) ^{3}x+3\,\sin \left ( x \right ) \left ( \cos \left ( x \right ) \right ) ^{2}-\sin \left ( x \right ) }{ \left ( \sin \left ( x \right ) \cos \left ( x \right ) x+ \left ( \cos \left ( x \right ) \right ) ^{2}-1 \right ) \cos \left ( x \right ) }} \,{\rm d}x}}\cos \left ( x \right ) \,{\rm d}x \right \} \]