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charset="UTF-8" X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 442F8160012 X-Stat-Signature: 4p66szxe6ndeusq4kpjggt9w95c9jjcj X-HE-Tag: 1676294810-231859 X-HE-Meta: U2FsdGVkX1/GSKX4fd/QEeQJ61v9z6icY9G+sYYFFP4JjrFGxrY/6QCOQGuQ17lbmE17SCfdIOcF98IPg3NlHoUffvjU03zjuabzwu5NHFMRMeYdFbxYA9DDOQT++KWW9Qmy4nfnK86q9cF+ndrcJuiB19zZMCqnRuRAyXxwauWz12laTzELQPaiaaIetNI+bvN+GXSKfp5YdJH9yzzC0BOMHtz23FrU/rl8WzX1dZggG4663TdgNeDrdywnLGk5WCoGJCZYtLQ02t6z9SjDcdtvDcmh4T+IiFe+pH9mZzIj0qVsWD/FuI1HPbvjSfAL34X2YDpTdLvuMWsdj3jhq61L8d+JuMfYTYnjzJUidzXOyPb8KC14CuJw13Nniii4c1k4sFSxAAftO9EVOMXViqK+hCOPZh2xc7lHpP9sCtqoH7SIw7KY7I9QXPY8Wv6qfaoIZPQEGHAPsx43ogQeO7MRMOvr3MRtRSrssSYa8MMqPfwNy3oiZ5MViI+dfcXMOi03CrqT50NYU7AZuiRRxJIUj+vG/2zPAp6NaVJRXcnzzlpMToQvyOJJlgj8ZmuynovIiduZhNGFVe5UVgNRsi6lj/fBS8J49UM95kFy4g4E62ZtvNCRCyclSmzuhBFeAWskFfVTT4ZwxYts0FX3XY/2/wzPYCDV1JL7b3Tenxu7n3+0ad7og8znh+0LQfbZbKzO2crR8GoflCisuN5KdRu+yPHRTT1MTzBftASsvDewGSTlxOx5vsM2ZXgURKZgmi8NYU20sxy67JdHoBgGQPkiJTwqi1luNszT+TU3jz5byzixzRIgLxm+UrsdZV+Vs4LpD0LO0K32WTsoDydKFwr62qEg4uEMI45QnkKxRiMGN3WuUttEUl8s6ql96I1+hEY2ChCXuZw26tUTdgls/vCitjPVjIooLV48JtFVMdaPWzWxb+R+C0jIZwMR+JamhVvI18K52DR0eMST0AP 5hcpOj7Y VUegfSI05m5GNGQ/H7BCoaj+rZPdy/RjJHhxomU2dlUDeGhfKR6wQ3VBY/psHU6jbG594EI3uGS9I10GYeKO06aLoTYV8mrjJEmlw3xkR4Lbkp03isWxNIqq8ErzTJiUYHz6CBiRVXoQOIShupEsn6MkgPm1+In5xC9kb0k4I37hsGuTQ/CaTsprae93mnZtfZH4Q+blamN15C9W5OAVtoW0qjiJfo0rPmJDKhlLzHr5WqyEPvzBYOZEBipSQGBiyvUY+sX8oSAhFeNNu7/cDuFgRLbPzYGDBKax8UXV4eevOtW0= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000137, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Feb 10, 2023 at 10:18 PM wrote: > > From: Andrey Konovalov > > Clean up comments in include/linux/stackdepot.h and lib/stackdepot.c: > > 1. Rework the initialization comment in stackdepot.h. > 2. Rework the header comment in stackdepot.c. > 3. Various clean-ups for other comments. > > Also adjust whitespaces for find_stack and depot_alloc_stack call sites. > > No functional changes. > > Signed-off-by: Andrey Konovalov Reviewed-by: Alexander Potapenko > - * Instead, stack depot maintains a hashtable of unique stacktraces. Since alloc > - * and free stacks repeat a lot, we save about 100x space. > - * Stacks are never removed from depot, so we store them contiguously one after > - * another in a contiguous memory allocation. > + * For example, KASAN needs to save allocation and free stack traces for each s/free/deallocation, maybe? (Here and below) > + * object. Storing two stack traces per object requires a lot of memory (e.g. > + * SLUB_DEBUG needs 256 bytes per object for that). Since allocation and free > + * stack traces often repeat, using stack depot allows to save about 100x space.