�����JFIF��XX����������    $.' ",#(7),01444'9=82<.342  2!!22222222222222222222222222222222222222222222222222�����"����4���������������������������� ���������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������,�PG"Z_�4�˷����kjز�Z�,F+��_z�,�© �����zh6�٨�ic�fu������������������������������������#ډb���_�N��?�����������wQ���5-�~�I���8���������������������������������TK<5o�Iv-������������������k�_U_������������������������������~b�M��d��������Ӝ�U�Hh��?]��E�w��Q���k�{��_}qFW7HTՑ��Y��F�����?_�'ϔ��_�Ջt������������������������=||I �����6�έ"�����D���/[�k�9����Y�8������ds|\���Ҿp6�Ҵ���]��.����6���z<�v��@]�i%������������������������$j��~����g��J>��no����pM[me�i$[�����������s�o�ᘨ�˸ nɜG-�ĨU�ycP���3.DB�li�;���������������������hj���x����7Z^�N�h��������N3u{�:j�����x�힞��#M��&��jL P@��_���� P�������������������&��o8��������9������@Sz���6�t7#O�ߋ �����s}Yf�T������lmr����Z)'N��k�۞p�����w\�T���������������ȯ?�8`���O��i{wﭹW�[�r�� ��Q4F�׊������3m&L�=��h3�������z~��#����\�l :�F,j@�� ʱ�wQT����8�"kJO����6�֚l������������������}����R�>ډK���]��y����&����p�}b������;N�1�m�r$����|��7�>e�@���B�TM*-i�H��g�D�)� E�m�|�ؘbҗ�a���Ҿ����������������t4�����o���G��*oCN�rP���Q��@z,|?W[0���������:�n,j���WiE��W������$~/�hp\��?��{(�0���+�Y8rΟ�+����>S-S���������������VN;���}�s?.����� w��9��˟<���Mq4�Wv'������{)0�1mB����V����W[��������8�/<� �%���wT^�5���b��)iM� p�g�N�&ݝ������������VO~��q���u���9��� ����!��J27�����$����O-���! �:���%H��� ـ�������y�ΠM=t{!S�� �oK8�������t<����è��������:a��������[������ա�H���~��w��Qz`�p����o�^ ������Q��n����� �,uu�C��$ ^���,�������8�#��:�6��e�|~�����������!�3��3.�\0�����q��o�4`.|� ����y�Q�`~;�d�ׯ,��O�Zw�������`73�v�܋�<�����Ȏ�� ـ4k��5�K�a�u�=9Yd��$>x�A�&�� j0� ���vF��� Y���|�y��� ~�6�@c��1vOp��������Ig�����4��l�OD�����L����� R���c���j�_�uX�6��3?nk��Wy�f;^*B� ��@���~a�`��Eu�������+�����6�L��.ü>��}y���}_�O�6�͐�:�Yr���G�X��kG������l^w����������~㒶sy���Iu�!���� W ��X��N�7BV��O��!X�2����wvG�R�f�T#�����t�/?���%8�^�W�aT����G�cL�M���I��(J����1~�8�?aT ���]����AS�E��(��*E}� 2������#I/�׍qz��^t�̔���������b�Yz4x����t�){ OH�����+(E��A&�N�������XT��o��"�XC����'���)}�J�z�p� ����~5�}�^����+�6����w��c��Q�|�Lp�d�H��}�(�.|����k��c4^�����"�����Z?ȕ ��a<�������L�!0�39C� �Eu�����C�F�Ew�ç ;�n?�*o���B�8�bʝ���'#Rqf����M}7����]�������s2tcS{�\icTx;�\��7K���P������ʇ Z O-��~�������c>"��?��������P�����E��O�8��@�8��G��Q�g�a�Վ���󁶠��䧘��_%#r�>�����1�z�a���eb��qcP��ѵ��n���#L��� =��׀t� L�7�`�����V����A{�C:�g���e@�����w1 Xp�3�c3�ġ�������p��M"'-�@n4���fG���B3�DJ�8[Jo�ߐ���gK)ƛ��$���� �������8�3�����+���� �����6�ʻ���� ���S�kI�*KZlT _`�������?��K�����QK�d���������B`�s}�>���`������*�>��,*@J�d�oF*�����弝��O}�k��s��]��y�ߘ�������c1G�V���<=�7��7����6��q�PT��tXԀ�!9*4�4Tހ���3XΛex�46�������Y��D ����� ����BdemDa����\�_l,����G�/���֌7���Y�](�xTt^%�GE�����4�}bT����ڹ�����;��Y)���B�Q��u��>J/J ���⮶.�XԄ��j�ݳ������+E��d ���r�5�_D�����1 ���o�� �B�x�΢�#����<��W�����8���R6�@���g�M�.��� dr�D��>(otU��@�x=��~v���2� ӣ�d�oBd�����3�eO�6�㣷����������ݜ�6��6Y��Qz`����S��{���\P��~z m5{J/L��1������<�e�ͅPu���b�]�ϔ��������'�������f�b� Zpw��c`"��i���BD@:)ִ�:�]��h���v�E��w���T�l�������P����"Ju�}��وV ��J��G6��. J/�Qgl߭�e�����@�z�Zev2u����)]կ���������7x�������s�M�-<ɯ�c��r��v�����@��$�ޮ}lk���a����'����>x��O\�Z������Fu>������ck#��&:��`�$��ai�>2Δ����l���oF[h�������lE�ܺ�Π���k:)���`������� $[6�����9�����kOw�\|�����8}������ބ:��񶐕��������I�A1/���=�2[�,�!��.}gN#�u����b���� ~���������݊��}34q�����d�E��L��������c��$���"�[q�U�硬g^��%B ��z���r�p�������J�ru%v\h�����1Y�ne`������ǥ:g����pQM~�^��Xi� ��`S�:V2������9.�P���V������?B�k�� ��������AEvw%�_�9C�Q����wKekP�ؠ�\������;Io d�{ ߞo�c1eP�����\� `����E=���@K<�Y��������eڼ�J����w����{av�F�'�M�@��������������/J��+9p����|]���������Iw &`���8���&�M�hg���[�{�������Xj���%��Ӓ�������������������$��(�����ʹN�������<>�I���RY�����K2�NPlL�ɀ�)��&e��������B+ь����(������������������� � �JTx����_?EZ� }@���� 6�U���뙢ط�z��dWI��n` D����噥�[��uV��"�G&�����Ú����2�g�}&m���������������������?ċ���"����Om#�������������������������� ��{���������������������ON��"S�X���Ne��ysQ���@�������������Fn��Vg�����dX�~nj����������������������]J�<�K]:����FW���b�������62����������=��5f����JKw����bf�X������������������������55��~J �%^�������:�-�QIE��P��v�nZum� z � ~ə ���� ���ة����;�f��\v�������g�8�1��f2�������������������������4;�V���ǔ�)�������������������9���1\������������������������������c��v�/'Ƞ�w������������������$�4�R-��t����������������������������������� e�6�/�ġ �̕Ecy�J���u�B���<�W�ַ~�w[B1L۲�-JS΂�{���΃�������������������������������������������A��20�c#���������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������@���� 0!1@AP"#2Q`$3V�%45a6�FRUq����� ������^7ׅ,$n��������+��F�`��2X'��0vM��p�L=�������5��8������u�p~���.�`r�����\����O��,ư�0oS ��_�M�����l���4�kv\JSd���x���SW�<��Ae�IX����������$I���w�:S���y���›R��9�Q[���,�5�;�@]�%���u�@ *ro�lbI �� ��+���%m:�͇ZV�����u�̉����θau<�fc�.����{�4Ա� �Q����*�Sm��8\ujqs]{kN���)qO�y�_*dJ�b�7���yQqI&9�ԌK!�M}�R�;�������S�T���1���i[U�ɵz�]��U)V�S6���3$K{��ߊ<�(� E]Զ[ǼENg�����'�\?#)Dkf��J���o��v���'�%ƞ�&K�u��!��b�35LX�Ϸ��63$K�a�;�9>,R��W��3�3� d�JeTYE.Mϧ��-�o�j3+y��y^�c�������VO�9NV\nd�1 ��!͕_)a�v;����թ�M�lWR1��)El��P;��yوÏ�u 3�k�5Pr6<�⒲l�!˞*��u־�n�!�l:����UNW ��%��Chx8vL'��X�@��*��)���̮��ˍ��� ����D-M�+J�U�kvK����+�x8��cY������?�Ԡ��~3mo��|�u@[XeY�C�\Kp�x8�oC�C�&����N�~3-H���� ��MX�s�u<`���~"WL��$8ξ��3���a�)|:@�m�\���^�`�@ҷ)�5p+��6���p�%i)P M���ngc�����#0Aruz���RL+xSS?���ʮ}()#�t��mˇ!��0}}y����<�e� �-ή�Ԩ��X������ MF���ԙ~l L.3���}�V뽺�v������멬��Nl�)�2����^�Iq��a��M��qG��T�����c3#������3U�Ǎ���}��לS�|qa��ڃ�+���-��2�f����/��bz��ڐ�� �ݼ[2�ç����k�X�2�* �Z�d���J�G����M*9W���s{��w���T��x��y,�in�O�v��]���n����P�$��JB@=4�OTI�n��e�22a\����q�d���%�$��(���:���: /*�K[PR�fr\nڙdN���F�n�$�4��[�� U�zƶ����� �mʋ���,�ao�u 3�z� �x��Kn����\[��VFmbE;�_U��&V�Gg�]L�۪&#n%�$ɯ��dG���D�TI=�%+AB�Ru#��b4�1�»x�cs�YzڙJG��f��Il���d�eF'T� iA��T���uC�$����Y��H?����[!G`}���ͪ� �纤Hv\������j�Ex�K���!���OiƸ�Yj�+u-<���'q����uN�*�r\��+�]���<�wOZ.fp�ێ��,-*)V?j-kÊ#�`�r��dV����(�ݽBk�����G�ƛk�QmUڗe��Z���f}|����8�8��a���i��3'J�����~G_�^���d�8w������ R�`(�~�.��u���l�s+g�bv���W���lGc}��u���afE~1�Ue������Z�0�8�=e�� f@/�jqEKQQ�J���oN��J���W5~M>$6�Lt�;$ʳ{���^��6�{����v6���ķܰg�V�cnn �~z�x�«�,2�u�?cE+Ș�H؎�%�Za�)���X>uW�Tz�Nyo����s���FQƤ��$��*�&�LLXL)�1�" L��eO��ɟ�9=���:t��Z���c��Ž���Y?�ӭV�wv�~,Y��r�ۗ�|�y��GaF�����C�����.�+� ���v1���fήJ�����]�S��T��B��n5sW}y�$��~z�'�c ��8 ��� ,! �p��VN�S��N�N�q��y8z˱�A��4��*��'������2n<�s���^ǧ˭P�Jޮɏ�U�G�L�J�*#��<�V��t7�8����TĜ>��i}K%,���)[��z�21z ?�N�i�n1?T�I�R#��m-�����������������1����lA�`��fT5+��ܐ�c�q՝��ʐ��,���3�f2U�եmab��#ŠdQ�y>\��)�SLY����w#��.���ʑ�f��� ,"+�w�~�N�'�c�O�3F�������N<���)j��&��,-� �љ���֊�_�zS���TǦ����w�>��?�������n��U仆�V���e�����0���$�C�d���rP �m�׈e�Xm�Vu� �L��.�bֹ��� �[Դaզ���*��\y�8�Է:�Ez\�0�Kq�C b��̘��cө���Q��=0Y��s�N��S.����3.���O�o:���#���v7�[#߫ ��5�܎�L���Er4���9n��COWlG�^��0k�%<���ZB���aB_���������'=��{i�v�l�$�uC���mƎҝ{�c㱼�y]���W�i ��ߧc��m�H� m�"�"�����;Y�ߝ�Z�Ǔ�����:S#��|}�y�,/k�Ld� TA�(�AI$+I3��;Y*���Z��}|��ӧO��d�v��..#:n��f>�>���ȶI�TX��� 8��y����"d�R�|�)0���=���n4��6ⲑ�+��r<�O�܂~zh�z����7ܓ�HH�Ga롏���nCo�>������a ���~]���R���̲c?�6(�q�;5%� |�uj�~z8R�=X��I�V=�|{v�Gj\gc��q����z�؋%M�ߍ����1y��#��@f^���^�>N������#x#۹��6�Y~�?�dfPO��{��P�4��V��u1E1J �*|���%����JN��`eWu�zk M6���q t[�� ��g�G���v��WIG��u_ft����5�j�"�Y�:T��ɐ���*�;� e5���4����q$C��2d�}���� _S�L#m�Yp��O�.�C�;��c����Hi#֩%+) �Ӎ��ƲV���SYź��g |���tj��3�8���r|���V��1#;.SQ�A[���S������#���`n�+���$��$�I �P\[�@�s��(�ED�z���P��])8�G#��0B��[ى��X�II�q<��9�~[Z멜�Z�⊔IWU&A>�P~�#��dp<�?����7���c��'~���5 ��+$���lx@�M�dm��n<=e�dyX��?{�|Aef ,|n3�<~z�ƃ�uۧ�����P��Y,�ӥQ�*g�#먙R�\���;T��i,��[9Qi歉����c>]9�� ��"�c��P�� �Md?٥��If�ت�u��k��/����F��9�c*9��Ǎ:�ØF���z�n*�@|I�ށ9����N3{'��[�'ͬ�Ҳ4��#}��!�V� Fu��,�,mTIk���v C�7v���B�6k�T9��1�*l� '~��ƞF��lU��'�M ����][ΩũJ_�{�i�I�n��$����L�� j��O�dx�����kza۪��#�E��Cl����x˘�o�����V���ɞ�ljr��)�/,�߬h�L��#��^��L�ф�,íMƁe�̩�NB�L�����iL����q�}��(��q��6IçJ$�W�E$��:������=#����(�K�B����zђ <��K(�N�۫K�w��^O{!����)��H���>x�������lx�?>Պ�+�>�W���,Ly!_�D���Ō�l���Q�!�[ �S����J��1��Ɛ�Y}��b,+�Lo�x�ɓ)����=�y�oh�@�꥟/��I��ѭ=��P�y9��� �ۍYӘ�e+�p�Jnϱ?V\SO%�(�t� ���=?MR�[Ș�����d�/ ��n�l��B�7j� ��!�;ӥ�/�[-���A�>��dN�sLj ��,ɪv��=1c�.SQ�O3�U���ƀ�ܽ�E����������̻��9G�ϷD�7(�}��Ävӌ\��y�_0[w ���<΍>����a_��[0+�L��F.�޺��f�>oN�T����q;���y\��bՃ��y�jH�<|q-eɏ�_?_9+P���Hp$�����[ux�K w�Mw��N�ی'$Y2�=��q���KB��P��~�������Yul:�[<����F1�2�O���5=d����]Y�sw:���Ϯ���E��j,_Q��X��z`H1,#II ��d�wr��P˂@�ZJV����y$�\y�{}��^~���[:N����ߌ�U�������O��d�����ؾe��${p>G��3c���Ė�lʌ�� ת��[��`ϱ�-W����dg�I��ig2��� ��}s ��ؤ(%#sS@���~���3�X�nRG�~\jc3�v��ӍL��M[JB�T��s3}��j�Nʖ��W����;7���ç?=X�F=-�=����q�ߚ���#���='�c��7���ڑW�I(O+=:uxq�������������e2�zi+�kuG�R��������0�&e�n���iT^J����~\jy���p'dtG��s����O��3����9* �b#Ɋ�� p������[Bws�T�>d4�ۧs���nv�n���U���_�~,�v����ƜJ1��s�� �QIz���)�(lv8M���U=�;����56��G���s#�K���MP�=��LvyGd��}�VwWBF�'�à �?MH�U�g2�� ����!�p�7Q��j��ڴ����=��j�u��� Jn�A s���uM������e��Ɔ�Ҕ�!)�'��8Ϣ�ٔ���ޝ(��Vp���צ֖d=�IC�J�Ǡ{q������kԭ�߸���i��@K����u�|�p=..�*+����x�����z[Aqġ#s2a�Ɗ���RR�)*HRsi�~�a &f��M��P����-K�L@��Z��Xy�'x�{}��Zm+���:�)�) IJ�-i�u���� ���ܒH��'��L(7�y�GӜq���� j��� 6ߌg1�g�o���,kر���tY�?W,���p���e���f�OQS��!K�۟cҒA�|ս�j�>��=⬒��˧L[�� �߿2JaB~R��u�:��Q�] �0H~���]�7��Ƽ�I���(�}��cq '�ήET���q�?f�ab���ӥvr� �)o��-Q��_'����ᴎo��K������;��V���o��%���~OK ����*��b�f:���-ťIR��`B�5!RB@���ï�� �u �̯e\�_U�_������� g�ES��3��������QT��a�����x����U<~�c?�*�#]�MW,[8O�a�x��]�1bC|踤�P��lw5V%�)�{t�<��d��5���0i�XSU��m:��Z�┵�i�"��1�^B�-��P�hJ��&)O��*�D��c�W��vM��)����}���P��ܗ-q����\mmζZ-l@�}��a��E�6��F�@��&Sg@���ݚ�M����� ȹ 4����#p�\H����dYDo�H���"��\��..R�B�H�z_�/5˘����6��KhJR��P�mƶi�m���3��,#c�co��q�a)*P�t����R�m�k�7x�D�E�\Y�閣_X�<���~�)���c[[�BP����6�Yq���S��0����%_����;��Àv�~�| VS؇ ��'O0��F0��\���U�-�d@�����7�SJ*z��3n��y��P����O����������m�~�P�3|Y��ʉr#�C�<�G~�.,! ���bqx���h~0=��!ǫ�jy����l��O,�[B��~��|9��ٱ����Xly�#�i�B��g%�S��������tˋ���e���ې��\[d�t)��.+u�|1 ������#�~Oj����hS�%��i.�~X���I�H�m��0n���c�1uE�q��cF�RF�o���7� �O�ꮧ� ���ۛ{��ʛi5�rw?׌#Qn�TW��~?y$��m\�\o����%W� ?=>S�N@�� �Ʈ���R����N�)�r"C�:��:����� �����#��qb��Y�. �6[��2K����2u�Ǧ�HYR��Q�MV��� �G�$��Q+.>�����nNH��q�^��� ����q��mM��V��D�+�-�#*�U�̒ ���p욳��u:�������IB���m����PV@O���r[b= �� ��1U�E��_Nm�yKbN�O���U�}�the�`�|6֮P>�\2�P�V���I�D�i�P�O;�9�r�mAHG�W�S]��J*�_�G��+kP�2����Ka�Z���H�'K�x�W�MZ%�O�YD�Rc+o��?�q��Ghm��d�S�oh�\�D�|:W������UA�Qc yT�q��������~^�H��/��#p�CZ���T�I�1�ӏT����4��"�ČZ�����}��`w�#�*,ʹ�� ��0�i��課�Om�*�da��^gJ݅{���l�e9uF#T�ֲ��̲�ٞC"�q���ߍ ոޑ�o#�XZTp����@ o�8��(jd��xw�]�,f���`~��|,s��^����f�1���t��|��m�򸄭/ctr��5s��7�9Q�4�H1꠲BB@�l9@���C�����+�wp�xu�£Yc�9��?`@#�o�mH�s2��)�=��2�.�l����jg�9$�Y�S�%*L������R�Y������7Z���,*=�䷘$�������arm�o�ϰ���UW.|�r�uf����IGw�t����Zwo��~5 ��YյhO+=8fF�)�W�7�L9lM�̘·Y���֘YLf�큹�pRF���99.A �"wz��=E\Z���'a� 2��Ǚ�#;�'}�G���*��l��^"q��+2FQ� hj��kŦ��${���ޮ-�T�٭cf�|�3#~�RJ����t��$b�(R��(����r���dx� >U b�&9,>���%E\� Ά�e�$��'�q't��*�א���ެ�b��-|d���SB�O�O��$�R+�H�)�܎�K��1m`;�J�2�Y~9��O�g8=vqD`K[�F)k�[���1m޼c��n���]s�k�z$@��)!I �x՝"v��9=�ZA=`Ɠi �:�E��)`�7��vI��}d�YI�_ �o�:ob���o ���3Q��&D&�2=�� �Ά��;>�h����y.*ⅥS������Ӭ�+q&����j|UƧ�����}���J0��WW< ۋS�)jQR�j���Ư��rN)�Gű�4Ѷ(�S)Ǣ�8��i��W52���No˓� ۍ%�5brOn�L�;�n��\G����=�^U�dI���8$�&���h��'���+�(������cȁ߫k�l��S^���cƗjԌE�ꭔ��gF���Ȓ��@���}O���*;e�v�WV���YJ\�]X'5��ղ�k�F��b 6R�o՜m��i N�i�����>J����?��lPm�U��}>_Z&�KK��q�r��I�D�Չ~�q�3fL�:S�e>���E���-G���{L�6p�e,8��������QI��h��a�Xa��U�A'���ʂ���s�+טIjP�-��y�8ۈZ?J$��W�P� ��R�s�]��|�l(�ԓ��sƊi��o(��S0���Y� 8�T97.�����WiL��c�~�dxc�E|�2!�X�K�Ƙਫ਼�$((�6�~|d9u+�qd�^3�89��Y�6L�.I�����?���iI�q���9�)O/뚅����O���X��X�V��ZF[�یgQ�L��K1���RҖr@v�#��X�l��F���Нy�S�8�7�kF!A��sM���^rkp�jP�DyS$N���q���nxҍ!U�f�!eh�i�2�m����`�Y�I�9r�6� �TF���C}/�y�^���Η���5d�'��9A-��J��>{�_l+�`��A���[�'��յ�ϛ#w:݅�%��X�}�&�PSt�Q�"�-��\縵�/����$Ɨh�Xb�*�y��BS����;W�ջ_mc�����vt?2}1�;qS�d�d~u:2k5�2�R�~�z+|HE!)�Ǟl��7`��0�<�,�2*���Hl-��x�^����'_TV�gZA�'j� ^�2Ϊ��N7t�����?w�� �x1��f��Iz�C-Ȗ��K�^q�;���-W�DvT�7��8�Z�������� hK�(P:��Q- �8�n�Z���܃e貾�<�1�YT<�,�����"�6{�/ �?�͟��|1�:�#g��W�>$����d��J��d�B���=��jf[��%rE^��il:��B���x���Sּ�1հ��,�=��*�7 fcG��#q� �eh?��2�7�����,�!7x��6�n�LC�4x��},Geǝ�tC.��vS �F�43��zz\��;QYC,6����~;RYS/6���|2���5���v��T��i����������mlv��������&� �nRh^ejR�LG�f���? �ۉҬܦƩ��|��Ȱ����>3����!v��i�ʯ�>�v��オ�X3e���_1z�Kȗ\<������!�8���V��]��?b�k41�Re��T�q��mz��TiOʦ�Z��Xq���L������q"+���2ۨ��8}�&N7XU7Ap�d�X��~�׿��&4e�o�F��� �H�����O���č�c�� 懴�6���͉��+)��v;j��ݷ�� �UV�� i��� j���Y9GdÒJ1��詞�����V?h��l�����l�cGs�ځ�������y�Ac������\V3�? �� ܙg�>qH�S,�E�W�[�㺨�uch�⍸�O�}���a��>�q�6�n6�����N6�q��������N� ���! 1AQaq�0@����"2BRb�#Pr���3C`��Scst���$4D���%Td���� ?�����N����a��3��m���C���w��������xA�m�q�m����m������$����4n淿t'��C"w��zU=D�\R+w�p+Y�T�&�պ@��ƃ��3ޯ?�Aﶂ��aŘ���@-�����Q�=���9D��ռ�ѻ@��M�V��P��܅�G5�f�Y<�u=,EC)�<�Fy'�"�&�չ�X~f��l�KԆV��?�� �W�N����=(� �;���{�r����ٌ�Y���h{�١������jW����P���Tc�����X�K�r��}���w�R��%��?���E��m�� �Y�q|����\lEE4����r���}�lsI�Y������f�$�=�d�yO����p�����yBj8jU�o�/�S��?�U��*������ˍ�0�������u�q�m [�?f����a�� )Q�>����6#������� ?����0UQ����,IX���(6ڵ[�DI�MNލ�c&���υ�j\��X�R|,4��� j������T�hA�e��^���d���b<����n�� �즇�=!���3�^�`j�h�ȓr��jẕ�c�,ٞX����-����a�ﶔ���#�$��]w�O��Ӫ�1y%��L�Y<�wg#�ǝ�̗`�x�xa�t�w��»1���o7o5��>�m뭛C���Uƃߜ}�C���y1Xνm�F8�jI���]����H���ۺиE@I�i;r�8ӭ�����V�F�Շ| ��&?�3|x�B�MuS�Ge�=Ӕ�#BE5G������Y!z��_e��q�р/W>|-�Ci߇�t�1ޯќd�R3�u��g�=0 5��[?�#͏��q�cf���H��{ ?u�=?�?ǯ���}Z��z���hmΔ�BFTW�����<�q��(v� ��!��z���iW]*�J�V�z��gX֧A�q�&��/w���u�gYӘa���; �i=����g:��?2�dž6�ى�k�4�>�Pxs����}������G�9���3 ���)gG�R<>r h�$��'nc�h�P��Bj��J�ҧH� -��N1���N��?��~��}-q!=��_2hc�M��l�vY%UE�@|�v����M2�.Y[|y�"Eï��K�ZF,�ɯ?,q�?v�M 80jx�"�;�9vk�����+ ֧�� �ȺU��?�%�vcV��mA�6��Qg^M�����A}�3�nl� QRN�l8�kkn�'�����(��M�7m9و�q���%ޟ���*h$Zk"��$�9��: �?U8�Sl��,,|ɒ��xH(ѷ����Gn�/Q�4�P��G�%��Ա8�N��!� �&�7�;���eKM7�4��9R/%����l�c>�x;������>��C�:�����t��h?aKX�bhe�ᜋ^�$�Iհ �hr7%F$�E��Fd���t��5���+�(M6�t����Ü�UU|zW�=a�Ts�Tg������dqP�Q����b'�m���1{|Y����X�N��b �P~��F^F:����k6�"�j!�� �I�r�`��1&�-$�Bevk:y���#y�w��I0��x��=D�4��tU���P�ZH��ڠ底taP��6����b>�xa�����Q�#� WeF��ŮNj�p�J* mQ�N�����*I�-*�ȩ�F�g�3 �5��V�ʊ�ɮ�a��5F���O@{���NX��?����H�]3��1�Ri_u��������ѕ�� ����0��� F��~��:60�p�͈�S��qX#a�5>���`�o&+�<2�D����: �������ڝ�$�nP���*)�N�|y�Ej�F�5ټ�e���ihy�Z �>���k�bH�a�v��h�-#���!�Po=@k̆IEN��@��}Ll?j�O������߭�ʞ���Q|A07x���wt!xf���I2?Z��<ץ�T���cU�j��]���陎Ltl �}5�ϓ��$�,��O�mˊ�;�@O��jE��j(�ا,��LX���LO���Ц�90�O �.����a��nA���7������j4 ��W��_ٓ���zW�jcB������y՗+EM�)d���N�g6�y1_x��p�$Lv�:��9�"z��p���ʙ$��^��JԼ*�ϭ����o���=x�Lj�6�J��u82�A�H�3$�ٕ@�=Vv�]�'�qEz�;I˼��)��=��ɯ���x �/�W(V���p�����$ �m�������u�����񶤑Oqˎ�T����r��㠚x�sr�GC��byp�G��1ߠ�w e�8�$⿄����/�M{*}��W�]˷.�CK\�ުx���/$�WP�w���r� |i���&�}�{�X� �>��$-��l���?-z���g����lΆ���(F���h�vS*���b���߲ڡn,|)mrH[���a�3�ר�[1��3o_�U�3�TC�$��(�=�)0�kgP���� ��u�^=��4 �WYCҸ:��vQ�ר�X�à��tk�m,�t*��^�,�}D*�� �"(�I��9R����>`�`��[~Q]�#af��i6l��8���6�:,s�s�N6�j"�A4���IuQ��6E,�GnH��zS�HO�uk�5$�I�4��ؤ�Q9�@��C����wp��BGv[]�u�Ov����0I4���\��y�����Q�Ѹ��~>Z��8�T��a��q�ޣ;z��a���/��S��I:�ܫ_�|������>=Z����8:�S��U�I�J��"IY���8%b8���H��:�QO�6�;7�I�S��J��ҌAά3��>c���E+&jf$eC+�z�;��V����� �r���ʺ������my�e���aQ�f&��6�ND���.:��NT�vm�<- u���ǝ\MvZY�N�NT��-A�>jr!S��n�O 1�3�Ns�%�3D@���`������ܟ 1�^c<���� �a�ɽ�̲�Xë#�w�|y�cW�=�9I*H8�p�^(4���՗�k��arOcW�tO�\�ƍR��8����'�K���I�Q�����?5�>[�}��yU�ײ -h��=��% q�ThG�2�)���"ו3]�!kB��*p�FDl�A���,�eEi�H�f�Ps�����5�H:�Փ~�H�0Dت�D�I����h�F3�������c��2���E��9�H��5�zԑ�ʚ�i�X�=:m�xg�hd(�v����׊�9iS��O��d@0ڽ���:�p�5�h-��t�&���X�q�ӕ,��ie�|���7A�2���O%P��E��htj��Y1��w�Ѓ!����  ���� ࢽ��My�7�\�a�@�ţ�J ��4�Ȼ�F�@o�̒?4�wx��)��]�P��~�����u�����5�����7X ��9��^ܩ�U;Iꭆ 5 �������eK2�7(�{|��Y׎ �V��\"���Z�1� Z�����}��(�Ǝ"�1S���_�vE30>���p;� ΝD��%x�W�?W?v����o�^V�i�d��r[��/&>�~`�9Wh��y�;���R���� ;;ɮT��?����r$�g1�K����A��C��c��K��l:�'��3 c�ﳯ*"t8�~l��)���m��+U,z��`(��>yJ�?����h>��]��v��ЍG*�{`��;y]��I�T� ;c��NU�fo¾h���/$���|NS���1�S�"�H��V���T���4��uhǜ�]�v;���5�͠x��'C\�SBpl���h}�N����� A�Bx���%��ޭ�l��/����T��w�ʽ]D�=����K���ž�r㻠l4�S�O?=�k �M:� ��c�C�a�#ha���)�ѐxc�s���gP�iG���{+���x���Q���I= �� z��ԫ+ �8"�k�ñ�j=|����c ��y��CF��/���*9ж�h{ �?4�o� ��k�m�Q�N�x��;�Y��4膚�a�w?�6�>�e]�����Q�r�:����g�,i"�����ԩA��*M�<�G��b�if��l^M��5�� �Ҩ�{����6J��ZJ�����P�*�����Y���ݛu�_4�9�I8�7���������,^ToR���m4�H��?�N�S�ѕw��/S��甍�@�9H�S�T��t�ƻ���ʒU��*{Xs�@����f������֒Li�K{H�w^���������Ϥm�tq���s� ���ք��f:��o~s��g�r��ט� �S�ѱC�e]�x���a��) ���(b-$(�j>�7q�B?ӕ�F��hV25r[7 Y� }L�R��}����*sg+��x�r�2�U=�*'WS��ZDW]�WǞ�<��叓���{�$�9Ou4��y�90-�1�'*D`�c�^o?(�9��u���ݐ��'PI&� f�Jݮ�������:wS����jfP1F:X �H�9dԯ����˝[�_54 �}*;@�ܨ�� ð�yn�T���?�ןd�#���4rG�ͨ��H�1�|-#���Mr�S3��G�3�����)�.᧏3v�z֑��r����$G"�`j �1t��x0<Ɔ�Wh6�y�6��,œ�Ga��gA����y��b��)���h�D��ß�_�m��ü �gG;��e�v��ݝ�nQ� ��C����-�*��o���y�a��M��I�>�<���]obD��"�:���G�A��-\%LT�8���c�)��+y76���o�Q�#*{�(F�⽕�y����=���rW�\p���۩�c���A���^e6��K������ʐ�cVf5$�'->���ՉN"���F�"�UQ@�f��Gb~��#�&�M=��8�ט�JNu9��D��[̤�s�o�~������� G��9T�tW^g5y$b��Y'��س�Ǵ�=��U-2 #�MC�t(�i� �lj�@Q 5�̣i�*�O����s�x�K�f��}\��M{E�V�{�υ��Ƈ�����);�H����I��fe�Lȣr�2��>��W��I�Ȃ6������i��k�� �5�YOxȺ����>��Y�f5'��|��H+��98pj�n�.O�y�������jY��~��i�w'������l�;�s�2��Y��:'lg�ꥴ)o#'Sa�a�K��Z� �m��}�`169�n���"���x��I ��*+� }F<��cГ���F�P�������ֹ*�PqX�x۩��,� ��N�� �4<-����%����:��7����W���u�`����� $�?�I��&����o��o��`v�>��P��"��l���4��5'�Z�gE���8���?��[�X�7(��.Q�-��*���ތL@̲����v��.5���[��=�t\+�CNܛ��,g�SQnH����}*F�G16���&:�t��4ُ"A��̣��$�b �|����#rs��a�����T�� ]�<�j��B�S�('$�ɻ� �wP;�/�n��?�ݜ��x�F��yUn�~mL*-�������Xf�wd^�a�}��f�,=t�׵i�.2/wpN�Ep8�OР���•��R�FJ� 55TZ��T �ɭ�<��]��/�0�r�@�f��V��V����Nz�G��^���7hZi����k��3�,kN�e|�vg�1{9]_i��X5y7� 8e]�U����'�-2,���e"����]ot�I��Y_��n�(JҼ��1�O ]bXc���Nu�No��pS���Q_���_�?i�~�x h5d'�(qw52] ��'ޤ�q��o1�R!���`ywy�A4u���h<קy���\[~�4�\ X�Wt/� 6�����n�F�a8��f���z �3$�t(���q��q�x��^�XWeN'p<-v�!�{�(>ӽDP7��ո0�y)�e$ٕv�Ih'Q�EA�m*�H��RI��=:��� ���4牢) �%_iN�ݧ�l]� �Nt���G��H�L��� ɱ�g<���1V�,�J~�ٹ�"K��Q�� 9�HS�9�?@��k����r�;we݁�]I�!{ �@�G�[�"��`���J:�n]�{�cA�E����V��ʆ���#��U9�6����j�#Y�m\��q�e4h�B�7��C�������d<�?J����1g:ٳ���=Y���D�p�ц� ׈ǔ��1�]26؜oS�'��9�V�FVu�P�h�9�xc�oq�X��p�o�5��Ա5$�9W�V(�[Ak�aY錎qf;�'�[�|���b�6�Ck��)��#a#a˙��8���=äh�4��2��C��4tm^ �n'c����]GQ$[Wҿ��i���vN�{Fu ��1�gx��1┷���N�m��{j-,��x�� Ūm�ЧS�[�s���Gna���䑴�� x�p 8<������97�Q���ϴ�v�aϚG��Rt�Һ׈�f^\r��WH�JU�7Z���y)�vg=����n��4�_)y��D'y�6�]�c�5̪��\� �PF�k����&�c;��cq�$~T�7j ���nç]�<�g ":�to�t}�159�<�/�8������m�b�K#g'I'.W������6��I/��>v��\�MN��g���m�A�yQL�4u�Lj�j9��#44�t��l^�}L����n��R��!��t��±]��r��h6ٍ>�yҏ�N��fU�� ���� Fm@�8}�/u��jb9������he:A�y�ծw��GpΧh�5����l}�3p468��)U��d��c����;Us/�֔�YX�1�O2��uq�s��`hwg�r~�{ R��mhN��؎*q 42�*th��>�#���E����#��Hv�O����q�}������6�e��\�,Wk�#���X��b>��p}�դ��3���T5��†��6��[��@��P�y*n��|'f�֧>�lư΂�̺����SU�'*�q�p�_S�����M�� '��c�6������m�� ySʨ;M��r���Ƌ�m�Kxo,���Gm�P��A�G�:��i��w�9�}M(�^�V��$ǒ�ѽ�9���|���� �a����J�SQ�a���r�B;����}���ٻ֢�2�%U���c�#�g���N�a�ݕ�'�v�[�OY'��3L�3�;,p�]@�S��{ls��X�'���c�jw��k'a�.��}�}&�� �dP�*�bK=ɍ!����;3n�gΊU�ߴmt�'*{,=SzfD� A��ko~�G�aoq�_mi}#�m�������P�Xhύ�����mxǍ�΂���巿zf��Q���c���|kc�����?���W��Y�$���_Lv����l߶��c���`?����l�j�ݲˏ!V��6����U�Ђ(A���4y)H���p�Z_�x��>���e���R��$�/�`^'3qˏ�-&Q�=?��CFVR �D�fV�9��{�8g�������n�h�(P"��6�[�D���< E�����~0<@�`�G�6����Hг�cc�� �c�K.5��D��d�B���`?�XQ��2��ٿyqo&+�1^� DW�0�ꊩ���G�#��Q�nL3��c���������/��x ��1�1�[y�x�პCW��C�c�UĨ80�m�e�4.{�m��u���I=��f�����0QRls9���f���������9���~f�����Ǩ��a�"@�8���ȁ�Q����#c�ic������G��$���G���r/$W�(��W���V�"��m�7�[m�A�m����bo��D� j����۳� l���^�k�h׽����� ��#� iXn�v��eT�k�a�^Y�4�BN���ĕ���0������� !01@Q"2AaPq3BR�������?�����@4�Q�����T3,���㺠�W�[=JK�Ϟ���2�r^7��vc�:�9 �E�ߴ�w�S#d���Ix��u��:��Hp��9E!�� V 2;73|F��9Y���*ʬ�F��D����u&���y؟��^EA��A��(ɩ���^��GV:ݜDy�`��Jr29ܾ�㝉��[���E;Fzx��YG��U�e�Y�C���� ����v-tx����I�sם�Ę�q��Eb�+P\ :>�i�C'�;�����k|z�رn�y]�#ǿb��Q��������w�����(�r|ӹs��[�D��2v-%��@;�8<a���[\o[ϧw��I!��*0�krs)�[�J9^��ʜ��p1)� "��/_>��o��<1����A�E�y^�C��`�x1'ܣn�p��s`l���fQ��):�l����b>�Me�jH^?�kl3(�z:���1ŠK&?Q�~�{�ٺ�h�y���/�[��V�|6��}�KbX����mn[-��7�5q�94�������dm���c^���h� X��5��<�eޘ>G���-�}�دB�ޟ� ��|�rt�M��V+�]�c?�-#ڛ��^ǂ}���Lkr���O��u�>�-D�ry� D?:ޞ�U��ǜ�7�V��?瓮�"�#���r��չģVR;�n���/_� ؉v�ݶe5d�b9��/O��009�G���5n�W����JpA�*�r9�>�1��.[t���s�F���nQ� V 77R�]�ɫ8����_0<՜�IF�u(v��4��F�k�3��E)��N:��yڮe��P�`�1}�$WS��J�SQ�N�j��ٺ��޵�#l���ј(�5=��5�lǏmoW�v-�1����v,W�mn��߀$x�<����v�j(����c]��@#��1������Ǔ���o'��u+����;G�#�޸��v-lη��/(`i⣍Pm^����ԯ̾9Z��F��������n��1��� ��]�[��)�'�������:�֪�W��FC����� �B9،!?���]��V��A�Վ�M��b�w��G F>_DȬ0¤�#�QR�[V��kz���m�w�"��9ZG�7'[��=�Q����j8R?�zf�\a�=��O�U����*oB�A�|G���2�54 �p��.w7� �� ���&������ξxGHp� B%��$g�����t�Џ򤵍z���HN�u�Я�-�'4��0���;_���3������� !01"@AQa2Pq#3BR�������?����ʩca��en��^��8���<�u#��m*08r��y�N"�<�Ѳ0��@\�p��� �����Kv�D��J8�Fҽ� �f�Y��-m�ybX�NP����}�!*8t(�OqѢ��Q�wW�K��ZD��Δ^e��!� ��B�K��p~�����e*l}z#9ң�k���q#�Ft�o��S�R����-�w�!�S���Ӥß|M�l޶V��!eˈ�8Y���c�ЮM2��tk���� ������J�fS����Ö*i/2�����n]�k�\���|4yX�8��U�P.���Ы[���l��@"�t�<������5�lF���vU�����W��W��;�b�cД^6[#7@vU�xgZv��F�6��Q,K�v��� �+Ъ��n��Ǣ��Ft���8��0��c�@�!�Zq s�v�t�;#](B��-�nῃ~���3g������5�J�%���O������n�kB�ĺ�.r��+���#�N$?�q�/�s�6��p��a����a��J/��M�8��6�ܰ"�*������ɗud"\w���aT(����[��F��U՛����RT�b���n�*��6���O��SJ�.�ij<�v�MT��R\c��5l�sZB>F��<7�;EA��{��E���Ö��1U/�#��d1�a�n.1ě����0�ʾR�h��|�R��Ao�3�m3 ��%�� ���28Q�� ��y��φ���H�To�7�lW>����#i`�q���c����a��� �m,B�-j����݋�'mR1Ήt�>��V��p���s�0IbI�C.���1R�ea�����]H�6�����������4B>��o��](��$B���m�����a�!=���?�B� K�Ǿ+�Ծ"�n���K��*��+��[T#�{�E�J�S����Q�����s�5�:�U�\wĐ�f�3����܆&�)�����I���Ԇw��E T�lrTf6Q|R�h:��[K�� �z��c֧�G�C��%\��_�a��84��HcO�bi��ؖV��7H �)*ģK~Xhչ0��4?�0��� �E<���}3���#���u�?�� ��|g�S�6ꊤ�|�I#Hڛ� �ա��w�X��9��7���Ŀ%�SL��y6č��|�F�a 8���b���$�sק�h���b9RAu7�˨p�Č�_\*w��묦��F ����4D~�f����|(�"m���NK��i�S�>�$d7SlA��/�²����SL��|6N�}���S�˯���g��]6��; �#�.��<���q'Q�1|KQ$�����񛩶"�$r�b:���N8�w@��8$�� �AjfG|~�9F ���Y��ʺ��Bwؒ������M:I岎�G��`s�YV5����6��A �b:�W���G�q%l�����F��H���7�������Fsv7���k�� 403WebShell
403Webshell
Server IP : 92.112.183.103  /  Your IP : 216.73.216.167
Web Server : LiteSpeed
System : Linux lt-bnk-web922.main-hosting.eu 4.18.0-553.70.1.lve.el8.x86_64 #1 SMP Wed Aug 20 14:42:18 UTC 2025 x86_64
User : u970350538 ( 970350538)
PHP Version : 7.4.33
Disable Function : NONE
MySQL : OFF  |  cURL : ON  |  WGET : ON  |  Perl : OFF  |  Python : ON  |  Sudo : OFF  |  Pkexec : OFF
Directory :  /opt/golang/1.22.0/src/runtime/

Upload File :
current_dir [ Writeable ] document_root [ Writeable ]

 

Command :


[ Back ]     

Current File : /opt/golang/1.22.0/src/runtime//trace2.go
// Copyright 2023 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

//go:build goexperiment.exectracer2

// Go execution tracer.
// The tracer captures a wide range of execution events like goroutine
// creation/blocking/unblocking, syscall enter/exit/block, GC-related events,
// changes of heap size, processor start/stop, etc and writes them to a buffer
// in a compact form. A precise nanosecond-precision timestamp and a stack
// trace is captured for most events.
//
// Tracer invariants (to keep the synchronization making sense):
// - An m that has a trace buffer must be on either the allm or sched.freem lists.
// - Any trace buffer mutation must either be happening in traceAdvance or between
//   a traceAcquire and a subsequent traceRelease.
// - traceAdvance cannot return until the previous generation's buffers are all flushed.
//
// See https://go.dev/issue/60773 for a link to the full design.

package runtime

import (
	"runtime/internal/atomic"
	"unsafe"
)

// Trace state.

// trace is global tracing context.
var trace struct {
	// trace.lock must only be acquired on the system stack where
	// stack splits cannot happen while it is held.
	lock mutex

	// Trace buffer management.
	//
	// First we check the empty list for any free buffers. If not, buffers
	// are allocated directly from the OS. Once they're filled up and/or
	// flushed, they end up on the full queue for trace.gen%2.
	//
	// The trace reader takes buffers off the full list one-by-one and
	// places them into reading until they're finished being read from.
	// Then they're placed onto the empty list.
	//
	// Protected by trace.lock.
	reading       *traceBuf // buffer currently handed off to user
	empty         *traceBuf // stack of empty buffers
	full          [2]traceBufQueue
	workAvailable atomic.Bool

	// State for the trace reader goroutine.
	//
	// Protected by trace.lock.
	readerGen     atomic.Uintptr // the generation the reader is currently reading for
	flushedGen    atomic.Uintptr // the last completed generation
	headerWritten bool           // whether ReadTrace has emitted trace header

	// doneSema is used to synchronize the reader and traceAdvance. Specifically,
	// it notifies traceAdvance that the reader is done with a generation.
	// Both semaphores are 0 by default (so, acquires block). traceAdvance
	// attempts to acquire for gen%2 after flushing the last buffers for gen.
	// Meanwhile the reader releases the sema for gen%2 when it has finished
	// processing gen.
	doneSema [2]uint32

	// Trace data tables for deduplicating data going into the trace.
	// There are 2 of each: one for gen%2, one for 1-gen%2.
	stackTab  [2]traceStackTable  // maps stack traces to unique ids
	stringTab [2]traceStringTable // maps strings to unique ids

	// cpuLogRead accepts CPU profile samples from the signal handler where
	// they're generated. There are two profBufs here: one for gen%2, one for
	// 1-gen%2. These profBufs use a three-word header to hold the IDs of the P, G,
	// and M (respectively) that were active at the time of the sample. Because
	// profBuf uses a record with all zeros in its header to indicate overflow,
	// we make sure to make the P field always non-zero: The ID of a real P will
	// start at bit 1, and bit 0 will be set. Samples that arrive while no P is
	// running (such as near syscalls) will set the first header field to 0b10.
	// This careful handling of the first header field allows us to store ID of
	// the active G directly in the second field, even though that will be 0
	// when sampling g0.
	//
	// Initialization and teardown of these fields is protected by traceAdvanceSema.
	cpuLogRead  [2]*profBuf
	signalLock  atomic.Uint32              // protects use of the following member, only usable in signal handlers
	cpuLogWrite [2]atomic.Pointer[profBuf] // copy of cpuLogRead for use in signal handlers, set without signalLock
	cpuSleep    *wakeableSleep
	cpuLogDone  <-chan struct{}
	cpuBuf      [2]*traceBuf

	reader atomic.Pointer[g] // goroutine that called ReadTrace, or nil

	// Fast mappings from enumerations to string IDs that are prepopulated
	// in the trace.
	markWorkerLabels [2][len(gcMarkWorkerModeStrings)]traceArg
	goStopReasons    [2][len(traceGoStopReasonStrings)]traceArg
	goBlockReasons   [2][len(traceBlockReasonStrings)]traceArg

	// Trace generation counter.
	gen            atomic.Uintptr
	lastNonZeroGen uintptr // last non-zero value of gen

	// shutdown is set when we are waiting for trace reader to finish after setting gen to 0
	//
	// Writes protected by trace.lock.
	shutdown atomic.Bool

	// Number of goroutines in syscall exiting slow path.
	exitingSyscall atomic.Int32

	// seqGC is the sequence counter for GC begin/end.
	//
	// Mutated only during stop-the-world.
	seqGC uint64
}

// Trace public API.

var (
	traceAdvanceSema  uint32 = 1
	traceShutdownSema uint32 = 1
)

// StartTrace enables tracing for the current process.
// While tracing, the data will be buffered and available via [ReadTrace].
// StartTrace returns an error if tracing is already enabled.
// Most clients should use the [runtime/trace] package or the [testing] package's
// -test.trace flag instead of calling StartTrace directly.
func StartTrace() error {
	if traceEnabled() || traceShuttingDown() {
		return errorString("tracing is already enabled")
	}
	// Block until cleanup of the last trace is done.
	semacquire(&traceShutdownSema)
	semrelease(&traceShutdownSema)

	// Hold traceAdvanceSema across trace start, since we'll want it on
	// the other side of tracing being enabled globally.
	semacquire(&traceAdvanceSema)

	// Initialize CPU profile -> trace ingestion.
	traceInitReadCPU()

	// Compute the first generation for this StartTrace.
	//
	// Note: we start from the last non-zero generation rather than 1 so we
	// can avoid resetting all the arrays indexed by gen%2 or gen%3. There's
	// more than one of each per m, p, and goroutine.
	firstGen := traceNextGen(trace.lastNonZeroGen)

	// Reset GC sequencer.
	trace.seqGC = 1

	// Reset trace reader state.
	trace.headerWritten = false
	trace.readerGen.Store(firstGen)
	trace.flushedGen.Store(0)

	// Register some basic strings in the string tables.
	traceRegisterLabelsAndReasons(firstGen)

	// Stop the world.
	//
	// The purpose of stopping the world is to make sure that no goroutine is in a
	// context where it could emit an event by bringing all goroutines to a safe point
	// with no opportunity to transition.
	//
	// The exception to this rule are goroutines that are concurrently exiting a syscall.
	// Those will all be forced into the syscalling slow path, and we'll just make sure
	// that we don't observe any goroutines in that critical section before starting
	// the world again.
	//
	// A good follow-up question to this is why stopping the world is necessary at all
	// given that we have traceAcquire and traceRelease. Unfortunately, those only help
	// us when tracing is already active (for performance, so when tracing is off the
	// tracing seqlock is left untouched). The main issue here is subtle: we're going to
	// want to obtain a correct starting status for each goroutine, but there are windows
	// of time in which we could read and emit an incorrect status. Specifically:
	//
	//	trace := traceAcquire()
	//  // <----> problem window
	//	casgstatus(gp, _Gwaiting, _Grunnable)
	//	if trace.ok() {
	//		trace.GoUnpark(gp, 2)
	//		traceRelease(trace)
	//	}
	//
	// More precisely, if we readgstatus for a gp while another goroutine is in the problem
	// window and that goroutine didn't observe that tracing had begun, then we might write
	// a GoStatus(GoWaiting) event for that goroutine, but it won't trace an event marking
	// the transition from GoWaiting to GoRunnable. The trace will then be broken, because
	// future events will be emitted assuming the tracer sees GoRunnable.
	//
	// In short, what we really need here is to make sure that the next time *any goroutine*
	// hits a traceAcquire, it sees that the trace is enabled.
	//
	// Note also that stopping the world is necessary to make sure sweep-related events are
	// coherent. Since the world is stopped and sweeps are non-preemptible, we can never start
	// the world and see an unpaired sweep 'end' event. Other parts of the tracer rely on this.
	stw := stopTheWorld(stwStartTrace)

	// Prevent sysmon from running any code that could generate events.
	lock(&sched.sysmonlock)

	// Reset mSyscallID on all Ps while we have them stationary and the trace is disabled.
	for _, pp := range allp {
		pp.trace.mSyscallID = -1
	}

	// Start tracing.
	//
	// After this executes, other Ms may start creating trace buffers and emitting
	// data into them.
	trace.gen.Store(firstGen)

	// Wait for exitingSyscall to drain.
	//
	// It may not monotonically decrease to zero, but in the limit it will always become
	// zero because the world is stopped and there are no available Ps for syscall-exited
	// goroutines to run on.
	//
	// Because we set gen before checking this, and because exitingSyscall is always incremented
	// *after* traceAcquire (which checks gen), we can be certain that when exitingSyscall is zero
	// that any goroutine that goes to exit a syscall from then on *must* observe the new gen.
	//
	// The critical section on each goroutine here is going to be quite short, so the likelihood
	// that we observe a zero value is high.
	for trace.exitingSyscall.Load() != 0 {
		osyield()
	}

	// Record some initial pieces of information.
	//
	// N.B. This will also emit a status event for this goroutine.
	tl := traceAcquire()
	tl.Gomaxprocs(gomaxprocs)  // Get this as early in the trace as possible. See comment in traceAdvance.
	tl.STWStart(stwStartTrace) // We didn't trace this above, so trace it now.

	// Record the fact that a GC is active, if applicable.
	if gcphase == _GCmark || gcphase == _GCmarktermination {
		tl.GCActive()
	}

	// Record the heap goal so we have it at the very beginning of the trace.
	tl.HeapGoal()

	// Make sure a ProcStatus is emitted for every P, while we're here.
	for _, pp := range allp {
		tl.writer().writeProcStatusForP(pp, pp == tl.mp.p.ptr()).end()
	}
	traceRelease(tl)

	unlock(&sched.sysmonlock)
	startTheWorld(stw)

	traceStartReadCPU()
	traceAdvancer.start()

	semrelease(&traceAdvanceSema)
	return nil
}

// StopTrace stops tracing, if it was previously enabled.
// StopTrace only returns after all the reads for the trace have completed.
func StopTrace() {
	traceAdvance(true)
}

// traceAdvance moves tracing to the next generation, and cleans up the current generation,
// ensuring that it's flushed out before returning. If stopTrace is true, it disables tracing
// altogether instead of advancing to the next generation.
//
// traceAdvanceSema must not be held.
func traceAdvance(stopTrace bool) {
	semacquire(&traceAdvanceSema)

	// Get the gen that we're advancing from. In this function we don't really care much
	// about the generation we're advancing _into_ since we'll do all the cleanup in this
	// generation for the next advancement.
	gen := trace.gen.Load()
	if gen == 0 {
		// We may end up here traceAdvance is called concurrently with StopTrace.
		semrelease(&traceAdvanceSema)
		return
	}

	// Write an EvFrequency event for this generation.
	//
	// N.B. This may block for quite a while to get a good frequency estimate, so make sure we do
	// this here and not e.g. on the trace reader.
	traceFrequency(gen)

	// Collect all the untraced Gs.
	type untracedG struct {
		gp           *g
		goid         uint64
		mid          int64
		status       uint32
		waitreason   waitReason
		inMarkAssist bool
	}
	var untracedGs []untracedG
	forEachGRace(func(gp *g) {
		// Make absolutely sure all Gs are ready for the next
		// generation. We need to do this even for dead Gs because
		// they may come alive with a new identity, and its status
		// traced bookkeeping might end up being stale.
		// We may miss totally new goroutines, but they'll always
		// have clean bookkeeping.
		gp.trace.readyNextGen(gen)
		// If the status was traced, nothing else to do.
		if gp.trace.statusWasTraced(gen) {
			return
		}
		// Scribble down information about this goroutine.
		ug := untracedG{gp: gp, mid: -1}
		systemstack(func() {
			me := getg().m.curg
			// We don't have to handle this G status transition because we
			// already eliminated ourselves from consideration above.
			casGToWaiting(me, _Grunning, waitReasonTraceGoroutineStatus)
			// We need to suspend and take ownership of the G to safely read its
			// goid. Note that we can't actually emit the event at this point
			// because we might stop the G in a window where it's unsafe to write
			// events based on the G's status. We need the global trace buffer flush
			// coming up to make sure we're not racing with the G.
			//
			// It should be very unlikely that we try to preempt a running G here.
			// The only situation that we might is that we're racing with a G
			// that's running for the first time in this generation. Therefore,
			// this should be relatively fast.
			s := suspendG(gp)
			if !s.dead {
				ug.goid = s.g.goid
				if s.g.m != nil {
					ug.mid = int64(s.g.m.procid)
				}
				ug.status = readgstatus(s.g) &^ _Gscan
				ug.waitreason = s.g.waitreason
				ug.inMarkAssist = s.g.inMarkAssist
			}
			resumeG(s)
			casgstatus(me, _Gwaiting, _Grunning)
		})
		if ug.goid != 0 {
			untracedGs = append(untracedGs, ug)
		}
	})

	if !stopTrace {
		// Re-register runtime goroutine labels and stop/block reasons.
		traceRegisterLabelsAndReasons(traceNextGen(gen))
	}

	// Now that we've done some of the heavy stuff, prevent the world from stopping.
	// This is necessary to ensure the consistency of the STW events. If we're feeling
	// adventurous we could lift this restriction and add a STWActive event, but the
	// cost of maintaining this consistency is low. We're not going to hold this semaphore
	// for very long and most STW periods are very short.
	// Once we hold worldsema, prevent preemption as well so we're not interrupted partway
	// through this. We want to get this done as soon as possible.
	semacquire(&worldsema)
	mp := acquirem()

	// Advance the generation or stop the trace.
	trace.lastNonZeroGen = gen
	if stopTrace {
		systemstack(func() {
			// Ordering is important here. Set shutdown first, then disable tracing,
			// so that conditions like (traceEnabled() || traceShuttingDown()) have
			// no opportunity to be false. Hold the trace lock so this update appears
			// atomic to the trace reader.
			lock(&trace.lock)
			trace.shutdown.Store(true)
			trace.gen.Store(0)
			unlock(&trace.lock)
		})
	} else {
		trace.gen.Store(traceNextGen(gen))
	}

	// Emit a ProcsChange event so we have one on record for each generation.
	// Let's emit it as soon as possible so that downstream tools can rely on the value
	// being there fairly soon in a generation.
	//
	// It's important that we do this before allowing stop-the-worlds again,
	// because the procs count could change.
	if !stopTrace {
		tl := traceAcquire()
		tl.Gomaxprocs(gomaxprocs)
		traceRelease(tl)
	}

	// Emit a GCActive event in the new generation if necessary.
	//
	// It's important that we do this before allowing stop-the-worlds again,
	// because that could emit global GC-related events.
	if !stopTrace && (gcphase == _GCmark || gcphase == _GCmarktermination) {
		tl := traceAcquire()
		tl.GCActive()
		traceRelease(tl)
	}

	// Preemption is OK again after this. If the world stops or whatever it's fine.
	// We're just cleaning up the last generation after this point.
	//
	// We also don't care if the GC starts again after this for the same reasons.
	releasem(mp)
	semrelease(&worldsema)

	// Snapshot allm and freem.
	//
	// Snapshotting after the generation counter update is sufficient.
	// Because an m must be on either allm or sched.freem if it has an active trace
	// buffer, new threads added to allm after this point must necessarily observe
	// the new generation number (sched.lock acts as a barrier).
	//
	// Threads that exit before this point and are on neither list explicitly
	// flush their own buffers in traceThreadDestroy.
	//
	// Snapshotting freem is necessary because Ms can continue to emit events
	// while they're still on that list. Removal from sched.freem is serialized with
	// this snapshot, so either we'll capture an m on sched.freem and race with
	// the removal to flush its buffers (resolved by traceThreadDestroy acquiring
	// the thread's seqlock, which one of us must win, so at least its old gen buffer
	// will be flushed in time for the new generation) or it will have flushed its
	// buffers before we snapshotted it to begin with.
	lock(&sched.lock)
	mToFlush := allm
	for mp := mToFlush; mp != nil; mp = mp.alllink {
		mp.trace.link = mp.alllink
	}
	for mp := sched.freem; mp != nil; mp = mp.freelink {
		mp.trace.link = mToFlush
		mToFlush = mp
	}
	unlock(&sched.lock)

	// Iterate over our snapshot, flushing every buffer until we're done.
	//
	// Because trace writers read the generation while the seqlock is
	// held, we can be certain that when there are no writers there are
	// also no stale generation values left. Therefore, it's safe to flush
	// any buffers that remain in that generation's slot.
	const debugDeadlock = false
	systemstack(func() {
		// Track iterations for some rudimentary deadlock detection.
		i := 0
		detectedDeadlock := false

		for mToFlush != nil {
			prev := &mToFlush
			for mp := *prev; mp != nil; {
				if mp.trace.seqlock.Load()%2 != 0 {
					// The M is writing. Come back to it later.
					prev = &mp.trace.link
					mp = mp.trace.link
					continue
				}
				// Flush the trace buffer.
				//
				// trace.lock needed for traceBufFlush, but also to synchronize
				// with traceThreadDestroy, which flushes both buffers unconditionally.
				lock(&trace.lock)
				bufp := &mp.trace.buf[gen%2]
				if *bufp != nil {
					traceBufFlush(*bufp, gen)
					*bufp = nil
				}
				unlock(&trace.lock)

				// Remove the m from the flush list.
				*prev = mp.trace.link
				mp.trace.link = nil
				mp = *prev
			}
			// Yield only if we're going to be going around the loop again.
			if mToFlush != nil {
				osyield()
			}

			if debugDeadlock {
				// Try to detect a deadlock. We probably shouldn't loop here
				// this many times.
				if i > 100000 && !detectedDeadlock {
					detectedDeadlock = true
					println("runtime: failing to flush")
					for mp := mToFlush; mp != nil; mp = mp.trace.link {
						print("runtime: m=", mp.id, "\n")
					}
				}
				i++
			}
		}
	})

	// At this point, the old generation is fully flushed minus stack and string
	// tables, CPU samples, and goroutines that haven't run at all during the last
	// generation.

	// Check to see if any Gs still haven't had events written out for them.
	statusWriter := unsafeTraceWriter(gen, nil)
	for _, ug := range untracedGs {
		if ug.gp.trace.statusWasTraced(gen) {
			// It was traced, we don't need to do anything.
			continue
		}
		// It still wasn't traced. Because we ensured all Ms stopped writing trace
		// events to the last generation, that must mean the G never had its status
		// traced in gen between when we recorded it and now. If that's true, the goid
		// and status we recorded then is exactly what we want right now.
		status := goStatusToTraceGoStatus(ug.status, ug.waitreason)
		statusWriter = statusWriter.writeGoStatus(ug.goid, ug.mid, status, ug.inMarkAssist)
	}
	statusWriter.flush().end()

	systemstack(func() {
		// Flush CPU samples, stacks, and strings for the last generation. This is safe,
		// because we're now certain no M is writing to the last generation.
		//
		// Ordering is important here. traceCPUFlush may generate new stacks and dumping
		// stacks may generate new strings.
		traceCPUFlush(gen)
		trace.stackTab[gen%2].dump(gen)
		trace.stringTab[gen%2].reset(gen)

		// That's it. This generation is done producing buffers.
		lock(&trace.lock)
		trace.flushedGen.Store(gen)
		unlock(&trace.lock)
	})

	if stopTrace {
		semacquire(&traceShutdownSema)

		// Finish off CPU profile reading.
		traceStopReadCPU()
	} else {
		// Go over each P and emit a status event for it if necessary.
		//
		// We do this at the beginning of the new generation instead of the
		// end like we do for goroutines because forEachP doesn't give us a
		// hook to skip Ps that have already been traced. Since we have to
		// preempt all Ps anyway, might as well stay consistent with StartTrace
		// which does this during the STW.
		semacquire(&worldsema)
		forEachP(waitReasonTraceProcStatus, func(pp *p) {
			tl := traceAcquire()
			if !pp.trace.statusWasTraced(tl.gen) {
				tl.writer().writeProcStatusForP(pp, false).end()
			}
			traceRelease(tl)
		})
		// Perform status reset on dead Ps because they just appear as idle.
		//
		// Holding worldsema prevents allp from changing.
		//
		// TODO(mknyszek): Consider explicitly emitting ProcCreate and ProcDestroy
		// events to indicate whether a P exists, rather than just making its
		// existence implicit.
		for _, pp := range allp[len(allp):cap(allp)] {
			pp.trace.readyNextGen(traceNextGen(gen))
		}
		semrelease(&worldsema)
	}

	// Block until the trace reader has finished processing the last generation.
	semacquire(&trace.doneSema[gen%2])
	if raceenabled {
		raceacquire(unsafe.Pointer(&trace.doneSema[gen%2]))
	}

	// Double-check that things look as we expect after advancing and perform some
	// final cleanup if the trace has fully stopped.
	systemstack(func() {
		lock(&trace.lock)
		if !trace.full[gen%2].empty() {
			throw("trace: non-empty full trace buffer for done generation")
		}
		if stopTrace {
			if !trace.full[1-(gen%2)].empty() {
				throw("trace: non-empty full trace buffer for next generation")
			}
			if trace.reading != nil || trace.reader.Load() != nil {
				throw("trace: reading after shutdown")
			}
			// Free all the empty buffers.
			for trace.empty != nil {
				buf := trace.empty
				trace.empty = buf.link
				sysFree(unsafe.Pointer(buf), unsafe.Sizeof(*buf), &memstats.other_sys)
			}
			// Clear trace.shutdown and other flags.
			trace.headerWritten = false
			trace.shutdown.Store(false)
		}
		unlock(&trace.lock)
	})

	if stopTrace {
		// Clear the sweep state on every P for the next time tracing is enabled.
		//
		// It may be stale in the next trace because we may have ended tracing in
		// the middle of a sweep on a P.
		//
		// It's fine not to call forEachP here because tracing is disabled and we
		// know at this point that nothing is calling into the tracer, but we do
		// need to look at dead Ps too just because GOMAXPROCS could have been called
		// at any point since we stopped tracing, and we have to ensure there's no
		// bad state on dead Ps too. Prevent a STW and a concurrent GOMAXPROCS that
		// might mutate allp by making ourselves briefly non-preemptible.
		mp := acquirem()
		for _, pp := range allp[:cap(allp)] {
			pp.trace.inSweep = false
			pp.trace.maySweep = false
			pp.trace.swept = 0
			pp.trace.reclaimed = 0
		}
		releasem(mp)
	}

	// Release the advance semaphore. If stopTrace is true we're still holding onto
	// traceShutdownSema.
	//
	// Do a direct handoff. Don't let one caller of traceAdvance starve
	// other calls to traceAdvance.
	semrelease1(&traceAdvanceSema, true, 0)

	if stopTrace {
		// Stop the traceAdvancer. We can't be holding traceAdvanceSema here because
		// we'll deadlock (we're blocked on the advancer goroutine exiting, but it
		// may be currently trying to acquire traceAdvanceSema).
		traceAdvancer.stop()
		semrelease(&traceShutdownSema)
	}
}

func traceNextGen(gen uintptr) uintptr {
	if gen == ^uintptr(0) {
		// gen is used both %2 and %3 and we want both patterns to continue when we loop around.
		// ^uint32(0) and ^uint64(0) are both odd and multiples of 3. Therefore the next generation
		// we want is even and one more than a multiple of 3. The smallest such number is 4.
		return 4
	}
	return gen + 1
}

// traceRegisterLabelsAndReasons re-registers mark worker labels and
// goroutine stop/block reasons in the string table for the provided
// generation. Note: the provided generation must not have started yet.
func traceRegisterLabelsAndReasons(gen uintptr) {
	for i, label := range gcMarkWorkerModeStrings[:] {
		trace.markWorkerLabels[gen%2][i] = traceArg(trace.stringTab[gen%2].put(gen, label))
	}
	for i, str := range traceBlockReasonStrings[:] {
		trace.goBlockReasons[gen%2][i] = traceArg(trace.stringTab[gen%2].put(gen, str))
	}
	for i, str := range traceGoStopReasonStrings[:] {
		trace.goStopReasons[gen%2][i] = traceArg(trace.stringTab[gen%2].put(gen, str))
	}
}

// ReadTrace returns the next chunk of binary tracing data, blocking until data
// is available. If tracing is turned off and all the data accumulated while it
// was on has been returned, ReadTrace returns nil. The caller must copy the
// returned data before calling ReadTrace again.
// ReadTrace must be called from one goroutine at a time.
func ReadTrace() []byte {
top:
	var buf []byte
	var park bool
	systemstack(func() {
		buf, park = readTrace0()
	})
	if park {
		gopark(func(gp *g, _ unsafe.Pointer) bool {
			if !trace.reader.CompareAndSwapNoWB(nil, gp) {
				// We're racing with another reader.
				// Wake up and handle this case.
				return false
			}

			if g2 := traceReader(); gp == g2 {
				// New data arrived between unlocking
				// and the CAS and we won the wake-up
				// race, so wake up directly.
				return false
			} else if g2 != nil {
				printlock()
				println("runtime: got trace reader", g2, g2.goid)
				throw("unexpected trace reader")
			}

			return true
		}, nil, waitReasonTraceReaderBlocked, traceBlockSystemGoroutine, 2)
		goto top
	}

	return buf
}

// readTrace0 is ReadTrace's continuation on g0. This must run on the
// system stack because it acquires trace.lock.
//
//go:systemstack
func readTrace0() (buf []byte, park bool) {
	if raceenabled {
		// g0 doesn't have a race context. Borrow the user G's.
		if getg().racectx != 0 {
			throw("expected racectx == 0")
		}
		getg().racectx = getg().m.curg.racectx
		// (This defer should get open-coded, which is safe on
		// the system stack.)
		defer func() { getg().racectx = 0 }()
	}

	// This function must not allocate while holding trace.lock:
	// allocation can call heap allocate, which will try to emit a trace
	// event while holding heap lock.
	lock(&trace.lock)

	if trace.reader.Load() != nil {
		// More than one goroutine reads trace. This is bad.
		// But we rather do not crash the program because of tracing,
		// because tracing can be enabled at runtime on prod servers.
		unlock(&trace.lock)
		println("runtime: ReadTrace called from multiple goroutines simultaneously")
		return nil, false
	}
	// Recycle the old buffer.
	if buf := trace.reading; buf != nil {
		buf.link = trace.empty
		trace.empty = buf
		trace.reading = nil
	}
	// Write trace header.
	if !trace.headerWritten {
		trace.headerWritten = true
		unlock(&trace.lock)
		return []byte("go 1.22 trace\x00\x00\x00"), false
	}

	// Read the next buffer.

	if trace.readerGen.Load() == 0 {
		trace.readerGen.Store(1)
	}
	var gen uintptr
	for {
		assertLockHeld(&trace.lock)
		gen = trace.readerGen.Load()

		// Check to see if we need to block for more data in this generation
		// or if we need to move our generation forward.
		if !trace.full[gen%2].empty() {
			break
		}
		// Most of the time readerGen is one generation ahead of flushedGen, as the
		// current generation is being read from. Then, once the last buffer is flushed
		// into readerGen, flushedGen will rise to meet it. At this point, the tracer
		// is waiting on the reader to finish flushing the last generation so that it
		// can continue to advance.
		if trace.flushedGen.Load() == gen {
			if trace.shutdown.Load() {
				unlock(&trace.lock)

				// Wake up anyone waiting for us to be done with this generation.
				//
				// Do this after reading trace.shutdown, because the thread we're
				// waking up is going to clear trace.shutdown.
				if raceenabled {
					// Model synchronization on trace.doneSema, which te race
					// detector does not see. This is required to avoid false
					// race reports on writer passed to trace.Start.
					racerelease(unsafe.Pointer(&trace.doneSema[gen%2]))
				}
				semrelease(&trace.doneSema[gen%2])

				// We're shutting down, and the last generation is fully
				// read. We're done.
				return nil, false
			}
			// The previous gen has had all of its buffers flushed, and
			// there's nothing else for us to read. Advance the generation
			// we're reading from and try again.
			trace.readerGen.Store(trace.gen.Load())
			unlock(&trace.lock)

			// Wake up anyone waiting for us to be done with this generation.
			//
			// Do this after reading gen to make sure we can't have the trace
			// advance until we've read it.
			if raceenabled {
				// See comment above in the shutdown case.
				racerelease(unsafe.Pointer(&trace.doneSema[gen%2]))
			}
			semrelease(&trace.doneSema[gen%2])

			// Reacquire the lock and go back to the top of the loop.
			lock(&trace.lock)
			continue
		}
		// Wait for new data.
		//
		// We don't simply use a note because the scheduler
		// executes this goroutine directly when it wakes up
		// (also a note would consume an M).
		//
		// Before we drop the lock, clear the workAvailable flag. Work can
		// only be queued with trace.lock held, so this is at least true until
		// we drop the lock.
		trace.workAvailable.Store(false)
		unlock(&trace.lock)
		return nil, true
	}
	// Pull a buffer.
	tbuf := trace.full[gen%2].pop()
	trace.reading = tbuf
	unlock(&trace.lock)
	return tbuf.arr[:tbuf.pos], false
}

// traceReader returns the trace reader that should be woken up, if any.
// Callers should first check (traceEnabled() || traceShuttingDown()).
//
// This must run on the system stack because it acquires trace.lock.
//
//go:systemstack
func traceReader() *g {
	gp := traceReaderAvailable()
	if gp == nil || !trace.reader.CompareAndSwapNoWB(gp, nil) {
		return nil
	}
	return gp
}

// traceReaderAvailable returns the trace reader if it is not currently
// scheduled and should be. Callers should first check that
// (traceEnabled() || traceShuttingDown()) is true.
func traceReaderAvailable() *g {
	// There are three conditions under which we definitely want to schedule
	// the reader:
	// - The reader is lagging behind in finishing off the last generation.
	//   In this case, trace buffers could even be empty, but the trace
	//   advancer will be waiting on the reader, so we have to make sure
	//   to schedule the reader ASAP.
	// - The reader has pending work to process for it's reader generation
	//   (assuming readerGen is not lagging behind). Note that we also want
	//   to be careful *not* to schedule the reader if there's no work to do.
	// - The trace is shutting down. The trace stopper blocks on the reader
	//   to finish, much like trace advancement.
	//
	// We also want to be careful not to schedule the reader if there's no
	// reason to.
	if trace.flushedGen.Load() == trace.readerGen.Load() || trace.workAvailable.Load() || trace.shutdown.Load() {
		return trace.reader.Load()
	}
	return nil
}

// Trace advancer goroutine.
var traceAdvancer traceAdvancerState

type traceAdvancerState struct {
	timer *wakeableSleep
	done  chan struct{}
}

// start starts a new traceAdvancer.
func (s *traceAdvancerState) start() {
	// Start a goroutine to periodically advance the trace generation.
	s.done = make(chan struct{})
	s.timer = newWakeableSleep()
	go func() {
		for traceEnabled() {
			// Set a timer to wake us up
			s.timer.sleep(int64(debug.traceadvanceperiod))

			// Try to advance the trace.
			traceAdvance(false)
		}
		s.done <- struct{}{}
	}()
}

// stop stops a traceAdvancer and blocks until it exits.
func (s *traceAdvancerState) stop() {
	s.timer.wake()
	<-s.done
	close(s.done)
	s.timer.close()
}

// traceAdvancePeriod is the approximate period between
// new generations.
const defaultTraceAdvancePeriod = 1e9 // 1 second.

// wakeableSleep manages a wakeable goroutine sleep.
//
// Users of this type must call init before first use and
// close to free up resources. Once close is called, init
// must be called before another use.
type wakeableSleep struct {
	timer *timer

	// lock protects access to wakeup, but not send/recv on it.
	lock   mutex
	wakeup chan struct{}
}

// newWakeableSleep initializes a new wakeableSleep and returns it.
func newWakeableSleep() *wakeableSleep {
	s := new(wakeableSleep)
	lockInit(&s.lock, lockRankWakeableSleep)
	s.wakeup = make(chan struct{}, 1)
	s.timer = new(timer)
	s.timer.arg = s
	s.timer.f = func(s any, _ uintptr) {
		s.(*wakeableSleep).wake()
	}
	return s
}

// sleep sleeps for the provided duration in nanoseconds or until
// another goroutine calls wake.
//
// Must not be called by more than one goroutine at a time and
// must not be called concurrently with close.
func (s *wakeableSleep) sleep(ns int64) {
	resetTimer(s.timer, nanotime()+ns)
	lock(&s.lock)
	if raceenabled {
		raceacquire(unsafe.Pointer(&s.lock))
	}
	wakeup := s.wakeup
	if raceenabled {
		racerelease(unsafe.Pointer(&s.lock))
	}
	unlock(&s.lock)
	<-wakeup
	stopTimer(s.timer)
}

// wake awakens any goroutine sleeping on the timer.
//
// Safe for concurrent use with all other methods.
func (s *wakeableSleep) wake() {
	// Grab the wakeup channel, which may be nil if we're
	// racing with close.
	lock(&s.lock)
	if raceenabled {
		raceacquire(unsafe.Pointer(&s.lock))
	}
	if s.wakeup != nil {
		// Non-blocking send.
		//
		// Others may also write to this channel and we don't
		// want to block on the receiver waking up. This also
		// effectively batches together wakeup notifications.
		select {
		case s.wakeup <- struct{}{}:
		default:
		}
	}
	if raceenabled {
		racerelease(unsafe.Pointer(&s.lock))
	}
	unlock(&s.lock)
}

// close wakes any goroutine sleeping on the timer and prevents
// further sleeping on it.
//
// Once close is called, the wakeableSleep must no longer be used.
//
// It must only be called once no goroutine is sleeping on the
// timer *and* nothing else will call wake concurrently.
func (s *wakeableSleep) close() {
	// Set wakeup to nil so that a late timer ends up being a no-op.
	lock(&s.lock)
	if raceenabled {
		raceacquire(unsafe.Pointer(&s.lock))
	}
	wakeup := s.wakeup
	s.wakeup = nil

	// Close the channel.
	close(wakeup)

	if raceenabled {
		racerelease(unsafe.Pointer(&s.lock))
	}
	unlock(&s.lock)
	return
}

Youez - 2016 - github.com/yon3zu
LinuXploit